A few minutes ago AeroPod launched for purchase on Kickstarter, though, the company is hardly new to the aero field. In fact, one could argue that nobody as has much experience (manufacturing or practical) with aerodynamic sensors in the industry than Velocomp. After all, they’ve been making aerodynamic driven cycling products for a decade, most recently with their PowerPod.
The $299 Kickstarter priced AeroPod is essentially stepping up the PowerPod both from a hardware and software standpoint to offer real-time aerodynamic information to a rider so that they can adjust their position (or gear) to improve their CdA values, which in turn either makes you more efficient or faster depending on how you use the data.
Now, I want to caution that this post primarily uses/shows a prototype based on their existing PowerPod hardware, it is NOT what the Kickstarter project is. Rather, it’s just that – a functional prototype. I’ll detail the differences later, as some of them are actually quite significant. But until I have one of those units in the future, this will at least illustrate what they’re doing. Note that this PowerPod looking device has both special hardware inside of it, as well as special software. So it’s not your run of the mill PowerPod unit, despite looking like it externally.
Now – there will be a small pile of folks that prefer direct force power meters over the PowerPod implementation. And that’s cool. Because the primary goal of the AeroPod is actually to be used with a direct force power meter. And that’s something that even Velocomp’s past detractors have agreed with the company on: If you can combine their captured aero data with a standalone direct force power meter, you can do some really fascinating things.
But, we’re getting ahead of ourselves. Let’s dive into the details first.
The Hardware:
What you see above with the coin next to it is the final hardware version, that I should be able to touch in the next 48 hours at Sea Otter. It’s not what I tested however.
As noted above, that hardware prototype isn’t ready yet. So instead I used a hardware and software modified PowerPod. That pod lacks some of the items of the final pod, specifically (according to Velocomp), here are the differences between the modified prototype I have and the final production unit coming:
1) AeroPod uses a pitot tube design which, which in their testing provides better wind measurement
2) AeroPod firmware has more optimizations remaining
3) Connect IQ app is isn’t final (including logging of CdA data to the .FIT file)
4) Smartphone app for setup is not finished
5) TT mount is not finished
6) Plastics tooling is not finished
While that may seem like a big list, most would agree that #3-6 are pretty minimal. #1 and #2 are more open-ended into what rat-holes one can go down, but only time will tell there. Certainly most players in the market have been spending considerable time with #1/#2, but at the same time they also lack a decade of producing in-market cycling aero products. So it’s hard to say either way.
So what does the final pod have in it? Well, I could re-write what they’ve written in different language, but in this case I’m just going to show you a snippet of the specs of the unit.
Some of this is fairly straightforward, like the ANT+/BLE pieces, that’s all expected. And the high definition power measure they already do on PowerPod today. Much of the first portion is just componentry specs. It’s hard for me to know whether or not that’s meaningful in the aero realm today, since most companies aren’t publishing such specs out there. However, I’d note that things like the “30% faster microprocessor”, is somewhat of a ‘neither here nor there’ thing. As a user, I shouldn’t care about how fast a processor is, as long as it’s invisible to me in terms of product functionality. At this point, everything in my testing seems reactive enough – so that’s fine.
Now, what is implied above that’s worthwhile pointing out is that you’re still getting a PowerPod power meter (non-direct force) with the product. Said differently, this is like PowerPod++. You get all the power meter broadcasting of the existing PowerPod product, plus all the new aero-specific elements focused on pairing with a direct force power meter.
The unit is planned to have a final weight of 40g, and will continue to use the GoPro style mount. It will also come with a standard mount seen here:
Though you can purchase a specific Garmin combo mount, like the one I tried below. Though it should work well with most other metal mounts (less so plastic mounts due to flex). There’s plenty of options on the market today.
The unit requires a direct force power meter for CdA measurement/reporting. It MUST have this. Any direct force power meter works. Which more or less means any power meter out there except PowerPod itself. So PowerTap, Stages, Power2Max, Garmin, SRM, Verve, Pioneer, ROTOR, Shimano, Favero, etc… Pick almost anything here.
Though, they caution against using single-leg varieties of power meters, as I would, since you’re going to see more variance there which would impact accuracy of CdA measurements. Given in aero testing you’re looking for gains in the 1-2% range, trying to deal with pedal balance issues in the 1-8% would likely significantly impact things. It may be something I’ll talk about down the road in my in-depth review.
Further, you will need a speed sensor, which is not included. Most folks have ANT+ speed sensors, so that’s not a huge deal per se. This is the same as the original PowerPod.
Finally, on compatibility, it’ll transmit in real-time to three platforms:
A) Garmin Connect IQ compatible devices (which is pretty much anything, even the new lower-priced Edge 130)
B) Their mobile app via Bluetooth Smart
C) Everysight Raptor glasses
For the purpose of this test I only tried the Connect IQ data field.
Test Riding:
Now I’ve only had the device since last Friday, so my time with it is limited to an initial calibration/configuration test ride, followed by a normal ride where I had segments that I was focused on capturing some aero data. Please be aware I did this as part of a larger ride. Said differently, I didn’t spend that entire ride focused on aero stuff, as a lot of the ride was focused on getting photos/videos/etc for various products this week. Speaking of that video content – here’s an entire run-through of not just the AeroPod, but also some more general thoughts on aero testing and the value/place for it.
Next, note they didn’t quite have a triathlon/TT bike mount ready last week, so we went with a road bike. Obviously, a large target audience here is triathletes, and that’s what I’ll test with down the road.
In any event, in order to get things calibrated, there were a pile of steps involved, mostly because it’s still beta and I had to use desktop software for it all. If I look at all of the aero systems I’ve beta tested to date, all of them have involved a fairly high level of setup complexity, and usually a fair bit of hand-holding by the company responsible. Not because that’s the end-state product, but just because that’s the point where the beta product sits. The AeroPod is no different here.
The main portion, however, that’s not going to change is the actual calibration ride. This simply involves doing an out and back course, approximately 2 minutes in each direction along the same route. This is identical to what Velocomp would do with their advanced calibration on the PowerPod units previously.
In my case, I selected a nearby bike path that was perfectly straight along a rowing basin (seen at left). This isn’t necessary at all, but it just happened to be convenient.
Once I was doing do a quick out and back, I did another two minutes of normal riding. At this point I’d start to get CdA and wind speed values. Ideally, you’d ride for another 10-15 minutes to let things stabilize before calling your calibration ride done. At which point you’d head back to the computer and connect to the app to set ‘default’ CdA values. These default values are essentially used as a baseline to compare against. This is ultimately what allows the app to give you a time benefit value, it is the value over this default baseline. My ‘default’ CdA was pretty darn high, partially cause I was having some beta issues getting the data to show fully on my Garmin during my test (that was later resolved). So don’t fuss about that too much.
With the default re-sent to the AeroPod (or, PowerPod prototype as it may be), I headed back out for another ride. This next ride was out in the middle of nowhere, largely on country roads. But before I did that I installed their beta Connect IQ data field. This data field allows me to view CdA information as well as wind speed and time benefit savings. Like most Connect IQ data fields, it only takes a second to install.
With that all set it was off I went riding along. Once out on clear road, I started experimenting with different positions, initially at about .38-.40.
At the risk of sounding obvious, as I went into less frontal positions (such as getting down into the drops on my bike), the CdA value reduced, down to below .300. This makes sense and is fairly logical. I’ll caution it was a bit tricky to take these photos at the same time as getting measurements since I’m actually holding an entire gimbal setup for the video portion. Thus, again, don’t entirely overthink the values in the photos.
When you’re doing this though, Velocomp is like many other companies in that they recommend you hold positions for at least a minute or two (ideally 2-3) so you an let things stabilize. This is virtually identical to what every other company I’ve tested aero devices with has said as well. Most of this is accomplished via smoothing the data.
As part of those numbers, it’s tracking the wind speed, which it knows because it’s paired to a speed sensor on the bike, thus knowing your actual ground speed. The CdA data is derived by knowing your power output from pairing it with your power output. Thus it’s able to use those two values and figure out when you’re putting out more power because you’re pedaling harder, versus the wind driving that equation.
In addition to the CdA value, the app also gives you the wind speed (which is helpful more as a sanity check), as well as the 40K TT time savings of the position over the baseline. As you modify your ‘final’ position you should update the baseline CdA values so that the time savings occurs. Of course, you can simply mentally know as well what your current position CdA value is and figure out whether it’s faster or not.
Note that at present if you’re below 15MPH the unit will not display a new CdA value, instead, it’ll show the ‘default’ value noted earlier.
Because I wasn’t able to test it on my triathlon bike it wasn’t quite an ideal platform for doing better aero tests. The road bike is fine, but it’s more difficult to get the various finite position adjustments that you’d see on a triathlon bike once settled down into aero position. Further, since I only had basically one usable day to do testing, and about 8,238 other things to do that day on the bike, I couldn’t devote an entire ride to just aero testing, which is ideally what you’d want to do so that you could better analyze it. As such, once I get back to Amsterdam next week after Sea Otter I’ll do some of that on a predictable route, so those that want to throw the data into various analytic suites can do so. Still, for the fun of it, here’s that full ride’s worth of crazy data.
There were areas that I was focused more on position and such, and the data looks much cleaner. And you can see at the end of the highlighted blue section when I sat up that everything all spiked as expected.
Note that this data will also show up/be saved in the .FIT file via your Garmin device, though the CIQ app that I was testing didn’t have that enabled yet – so I can’t show you that portion.
Also, the prototype unit I tested doesn’t quite get as high of resolution of data as their incoming hardware. So once I’ve got a chance to test that, I’ll have a better feel for the overall system. In many ways though, that’s pretty much the norm for all of these aero systems I’ve tested – it’s usually a cobbled-together Frankenstein type setup. Not in a bad way, just in a normal prototype way – that’s how product engineering works.
Going Forward:
As I’ve said on my other aero pieces, one of the challenges I have with the aero portion is that at this stage it’s pretty hard to refute or confirm any aero claim I see. There’s a lot of math one can do to get close, but that doesn’t really take into account the actual nuances of the day out on the road. Things like road conditions, random chunks of cobblestones I crossed, and so-on. Ideally, I’ll be able to find a neat clean repeatable short looped route nearby me to do tests with (where braking doesn’t often occur). It shouldn’t be hard, since there’s endless miles of beautiful country roads.
Until then, this is really just a preview of what they’re doing. Like others that I’ve written about – I’m not at this point passing judgment on accuracy claims or the like. And I’d caution that there are really only a handful of people out there in the cycling (aero) industry who I’d trust to make those claims. Still, I’d like to see all manufacturers – including Velocomp – find ways to backup their claims via 3rd party validation. Be it in a wind tunnel or some other platform that can really support any marketing claims they make. That can also to some degree be through comprehensive white paper like what we saw AeroLab do as well. More data is always better.
Finally, as for the project itself, they’re on Kickstarter from now for the next 29 days. The Kickstarter variants start at $299 (though down the road retail will be $499). They’re currently planning on delivering this July. I suspect that’s an achievable date, but as always, it’s Kickstarter. And it shouldn’t be forgotten they’ve been the *only* Kickstarter sports tech project that came close to hitting their previous dates, missing it by only about 3-5 days if I remember correctly. It also helps that manufacturing, supply, and the whole aero puzzle isn’t really new to them. I think their single biggest risk is simply re-engineering their app side to not be cumbersome. It needs to be super clean, super easy to use, and totally driven by a mobile phone. That’s the baseline for success in 2018 with a cycling device.
With that – thanks for reading!
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Second post in two days where I’ve seen someone suggest a manufacturer should give them a new version of a product. Would you expect Ford to buy you a new car when a new model comes out because you bought one of the old ones?
In the past Velocomp has been very good at offering upgrades to previous owners of their products. They would usually have a trade in program of sorts.
This is NOT true that the old hardware cannot measure realtime CDA. This was offered as an upgrade with Newton cycling computers (powerpod’s older brother w/ display and same basic hardware) and has been for years:
I have no doubt that this new product is more optimized for the job, but it doesn’t mean the old hardware cannot do it. It would certainly be reasonable to release the software as an upgrade (for a price) to existing users (with the caveat that the data may be x% more error-prone).
I think it would be more accurate to say the Velocomp claimed the Newton and Powerpod could be used with a DFPM to measure CdA. When I paired my Newton with a DFPM I did generate numbers that were probably somewhat related to CdA but the results were so unreliable as to be almost useless.
Now they are saying, in effect, that this time they really can measure CdA.
I’d love to see data to support the claims before I drink the Kool Aid aggain.
We did our original CdA work in 2008, with a product called the “iAero”. Its ideas were sound but there were problems with its implementation (mostly sensor quality), that eventually caused us to discontinue the product a year later.
We did leave the 2008 CdA feature in place in firmware, but we did not promote it, and we did zero work to update it.
Last year we began active work on updating our CdA measurement hardware and firmware, and much has changed. If you’d like to see some data, here is a link to some on-the-road measurements performed by one of our beta testers:
I know. I didn’t mean to imply that a false claim was made. My chronologically out of order comment (sorry) was in response to an April 19 post by Adam: “Not to mention that it’s completely technologically unfeasible to do what the AeroPod does with the PowerPod hardware, e.g. measuring wind yaw angle”.
I was trying to point out that the AeroPod does not measure (or claim to measure) wind yaw angle.
Am I correct to assume that these hardware/firmware changes, which improved the CdA accuracy, resulted from improving the underlying wind speed and power accuracy?
Ray, do you have any *opinion* about how this compares to what other companies have announced? From a hardware standpoint I guess if the windspeed sensor is good, the rest is software, right?
I’ve had the idea of using a wind speed meter together with a power meter years ago, although I found out pretty quickly that available smartphone wind sensors for drones/sailing aren’t good enough. The price seems reasonable and I might just finally get that toy :-)
As someone who does computational modeling for a living, I find this very cool. You have to compensate for the 1-2% error from the typical power meters. Your comments about smoothing suggest they are using averaging to help compensate, but presumably the power meter data error has some systematic component (or at least effectively systematic over the relevant time intervals of approximately real-time data) so that simple time averaging won’t just wash the errors out. Throw in some noise on the aerodynamic measurements on top of the power uncertainties, and it must be very challenging to pull a meaningful signal out. I’d love to know how they actually do it, but that’s probably proprietary.
You’ve frequently talked about how you thought companies like Velocomp should do this type of device, but I was always skeptical that it was feasible given the scale of the uncertainties on the inputs and the relatively small range of variations due to aerodynamics for small changes in rider position. If they have accomplished it, I’m impressed! As you say, I would love to see the validation data against some known data like a wind tunnel.
I’m going for it. I had the original powerpod but have since upgraded to some p1s. However, I’m planning on a new bike soon so my current bike will be used for commuting. The plan is to use the new pod to get a super accurate cdA which i’ll use in the old pod on the old bike so I can keep track of how my commutes might affect my training.
Plus also use the new pod to get the cdA data on the new (more aero) bike obviously.
I saw the pre-launch kickstarter page last week (via JH@powerpod) and have to say I thought ‘this is it’. It looks like very many boxes have been ticked.
Ray, what are your thoughts on the levels of pricing that the CONSUMER market will bear?
It’s a difficult question as the consumer market is somewhat in its infancy for this type of product/solution.
FWIW I thought the Kickstarter price was spot on to attract lots of takers. I wasn’t so sure in the medium term if $499 would attract too many sales once the initial bump of sales is satisfied.
I think the $299 pricing is very much in line with expectations.
I think the $499-$800 pricing numerous companies have talked about entering at is tricky. At that price point you definitely lower your volume significantly, since it becomes more of a front of the pack tool than a mid to front of the pack triathlete tool*. Also, when you get into the $499-$800 range, you’ve increased the requirement to support accuracy claims. Said differently, consumers expect more of you. Which doesn’t meant at $299 you can deliver crap, but…consumers are willing to put up with more if they save half.
A lot of companies will be watching this carefully. Aeropod has the slight challenge of history and critics that like to see it knocked down (for whatever long ago reasons). So they’re less likely to get some of the cycling media ‘lift’ that other unknown startup entrants might get. It’s somewhat ironic, because even talking to a few aero folks last night at the CIQ event, they’d admit that nobody has better experience in this field [outdoor aero devices] than Velocomp. So we’ll see.
*One could also say a coaching tool used across multiple clients, but I actually don’t think that harnesses the real power of real-time CdA. The point is to be able to use it on race day, not just a few training sessions.
It’s a shame that others have got the headlines, John really knows his onions and on a bumpy English backroad I’ve had repeatable, accurate, verifiable measurements (known baseline).
This will be a great evolution, I note that Aerolab and co are looking at North of $1000. this is proven tech and expertise which has been refined, not a new stab in the dark.
The other day, I wanted to see if a hand position adjustment had changed my helmet choice.
Loaded up, 6 mins (plus 3 for cal) later had my answer.
The power value displayed on your Garmin, is this provided by your DFPM or the AeroPod? I like the idea of knowing wind speed and CdA but would prefer to have the power values from my DFPM displayed and recorded.
Dave is correct. The estimated left/right part is no biggie since it’s not leveraged here. The total power portion is, which the C1 captures without issue (as does the Power2Max/Quarq/etc options).
If a Garmin could record two power streams, could Velocomp write an IQ app to do the deconvolution from PowerPod and DFPM in the head unit? (I own two PowerPods and a DFPM). Their Newton also provided real time CDA using the same model.
EDIT: will the new Isaac software shown mitigate the cost of the CdA add-on cost needed for us PowerPod users currently? That would help a little towards the cost.
For me the biggest problem with the PowerPod was the reliability of the hardware. I had to change 2 units before I finally lost patience and decided to go for a PowerTap hub (which I like a lot). It was a pain sending it to the US and then waiting for the replacement to reach my part of Europe.
So I hope that Velocomp stepped their game up in the hardware department for the new model.
I’m sorry you had problems. We’ve definitely learned some things that will improve reliability of AeroPod, and we’ve already implemented those improvements in current production of PowerPod.
Good to hear that you are improving the reliability.
While I didn’t like the logistics of the replacements I must say that you were always cooperative and answered my inquiries fast. So, thank you for that.
Does Wahoo have any functionality to support 3rd party data fields or add data fields as they go along? That’s one thing I really didn’t think about when I bought my Bolt and would prohibit my from getting a device like this.
They can (and do). I don’t know of the Velocomp folks have approached them. But as an example, the Quarq TyreWiz product also announced today will work with the Wahoo units for recording/showing data from the tire pressure sensor.
We reached out to Wahoo. They informed us that there is an ANT working group for developing CdA standards, and that they would implement the working group standard.
We have no clue when that standard will be finished, so in the mean time we have already developed our own CdA implementation, which will be supported in Garmin Connect IQ, Everysight Raptor, Lezyne bike computers, and PowerHouse app for iOS/Android.
If the CIQ app could access altitude/grade from the Garmin head unit with enough precision, would this also show me mechanical resistance that could then further be broken down into rolling and other resistances using cadence, gear etc? Could be memory lapse but I though some of the other ones promised rolling resistance as well … do those have some sensors etc that this one does not?
Understand that aero is where the big gains are and don’t know whether the other resistances are below or above noise and power meter accuracy level, but would be nice if one could optimize not “just” position but also tire air pressure etc…
It would be better of CIQ app could access altitude/grade from the Aeropod itself (as it’s much more precise than Garmin sensor), or even better – take the rolling resistance parameter from Aeropod directly (it calculates power so it has to estimate rolling resistance anyway).
I’m sure this market area will open up in the next few years – but having something on the market now, however flawed, is better than the promise of something better at a mystery point in the future.
re: the Garmin-Alphamantis, remember how long it took vector to come to market after garmin acquired them and look how long it too to become a mature product you might want to buy.
what I’m saying is that $299 seems like a reasonable gamble to me :)
Very excited about this! Currently testing several of the various options out there (3D scans, real world testing (data only), wind tunnel, velodrome, etc). The interest and effort going into aero testing is a great step forward for those of us doing performance modeling and trying to nail down that last piece of high variability data. Getting into the right ballpark (even just two decimals) will do wonders for real world modeling, goal setting, and race planning. This 299 (to 350) price point seems like a really sweet spot so it will be interesting to see how the data compares to options above and to real world modeling.
Thanks for posting this Ray, I just got 349$ option all others were gone, I’m a sucker for new toys, and your video made decision easy, I can see it does work, wondering about 0.000 accuracy but hey looks good, and I’m not waiting for garmin/alphamentis stuff for god knows how long.
Question: is Isaac software included with this hardware? Will Garmin record CDA data to fit file as additional data field and I will need to run some kind of app?
Cheers
Battery will last for about 25 hours of ride file recording, assuming you start from a full charge. The battery is rechargeable but is not user replaceable.
Since AeroPod’s Connect IQ app writes CdA data into the .fit file, I assume that it also writes wind speed data. Is my assumption correct?
If so, might Strava (for example) be interested in allowing cyclists to share their headwind, just as they do elevation gain?
Why would there be any connection between writing CdA and writing wind speed? The relative wind speed is included in the ibr data files that Newton and presumably Powerpod record so Isaac could use that data for post-ride analysis but if the CdA calculations are done on the Aeropod the Connect IQ app would not need Wind Speed data.
The prototype Connect IQ app (the version reviewed by Ray) displays CdA and wind speed, but doesn’t record them. When John Hamann commented that an upcoming version of the app “will record CdA data into the .fit file” I wanted a confirmation that it will record wind speed, too.
Frankly, I am more excited about wind speed than CdA. For every cyclist with the slightest interest in measuring real time CdA, there are probably at least 100 cyclists who already have a keen interest in measuring (and uploading and sharing) the wind conditions they experience during their bike rides. Most bike rides are neither races nor training sessions, and wind speed (and yaw) are more significant factors affecting bike rides (including races and training sessions), than CdA. They also change much more often and in a wider range.
But in any case, I want to measure wind speed and CdA both; and when I do that with PowerPod I am more content with the accuracy of the wind speed than that of the CdA. Hardware and software improvements from PowerPod to AeroPod may indeed be significant, but wind speed will always be more accurate than CdA. This actuality is dictated by the physics of the situation.
Hi John – how does the aeropod record data to .fit files? I’ve done few rides and while I see the data on the screen and can load them into the Isaac software – I can’t see anything in the .fit file. WKO4 doesn’t show extra data, neither does garmin connect.
Are we still in the testing phase? The CDA ConnectIQ field is not available through the ConnectIQ store and had to be installed manually on the device.
The Aeropod does not record FIT file data. It broadcasts data to the Connect IQ app using Ant+ but that app does not (yet?) record data to a FIT file either.
The Aeropod does store data that can be analysed in Isaac but the current version of Isaac does not export to FIT files either.
With the current firmware if you pair a heartrate monitor with the Aeropod the heartrate channel should be just that.
If you do NOT pair a heartrate monitor with Aeropod then the Aeropod’s heartrate channel in Isaac will contain the CdA data recorded by Aeropod. Each “heartrate” value will be equal to the value CdA*250 IIRC. There’s a more detailed explanation at the Velocomp forum.
I’m not certain but I don’t think the Aeropod puts any data into the head unit’s heartrate channel.
Pawel Chalacis: In Isaac / Edit Profiles / Wireless IDs, the number in the data field for HR ID should belong to your heart rate sensor, and the “enabled” light button should be selected. I don’t have experience with AeroPod, but that is how PowerPod records my HR data. It doesn’t record anyone else’s heart rate. When I don’t wear my HRM, Isaac shows no heart rate and the HR column in the csv file has no data in it.
A paid for upgrade is more inline with what I was thinking in my post above.
If I’ve understood what Ray tested correctly, it was updated firmware on an existing Powerpod.
I’d happily pay for that, and it could be similaf to an existing paid for software upgrade that Velocomp offer for powerstroke analysis and after the ride CdA analysis.
So if the existing powerpod device is açcurate enough to capture CdA data, I’d imagine there is a large existing user base who would pay a couple of hundred dollars for a software upgrade.
And by the way I’ve also backed the Kickstarter campaign. I’m massively excited by this whole new area of realtime CdA measurement, and can’t wait to start testing it out.
How cool would it be to be able to have an alert on my head unit when my CdA exceeds a certain threshold during a race? To remind me to get back into proper aero position as I fatigue towards the end the bike leg. It’s the future….
The unit I tested was a modified (harware and software) PowerPod they sent over.
My understanding is there is/was concerns with the existing PowerPod hardware in terms of providing a stable real-time CdA value. Versus data that’s processed afterwards in Issac.
I was an early PowerPod backer, and am happy to be ‘Backer No. 13’ of the AeroPod. I’m impressed with Velocomp (John’s) technical understanding and achievements.
I’m not as worried as some about absolute accuracy – my rear hub DF power meter can be as much as 7% different to a pedal power meter, and it would still be perfectly acceptable.
I do ultra-endurance bikepacking races. After ‘time in the saddle’, aerodynamics is the most important factor. I know that one feedbag has a minor aero effect, and it feels that two feedbags has a more-than-double effect. I want to test this, comparatively. Is a small hydration / food pack on my back going to slow me down more than a larger seat pack?
I’m really looking forward to a successful product launch!
Notio Konnect & Garmin Alphamantis, so sorry but i’m tired to wait how you jokes to the people, promisses and promisses and pure smoke with a high prices, sorry my stupids first brands, i’m a Hammerhead Karoo user and now supporting this device!
I’m not convinced this product will be useful or actually do what it claims to do. Having used the Newton with a DPFM, I occasionally got some insight into my CdA, but more often than not, it was just a random number generator. I put a lot of time into my testing and tried to be rigorous in my approach, but ultimately, the technology failed. The Newton really doesn’t live up to the the claim of measuring CdA, at least in my experience — at best, it estimated. I don’t regret my purchase of the Newton (and supplied software) because it’s built on a sound understanding of the physics; using the Newton afforded me a unique learning activity but I don’t think you can get qualifiedly good data from a single air-port or piton—it’s just not representative of the bigger picture. The Aeropod may be an improvement, but I’m not convinced: I’ll stick with using the Virtual Elevation (“Chunging it”) module in GoldenCheetah or the regression method. The cost is nil, and the data derived is real and actionable.
We have done a lot of work to get from Newton performance to AeroPod–new sensors, new algorithms, new wind port. We are using elite time trialists for testing, who have been wind tunnel measured, to perform comparisons. Their AeroPod data is great.
Going even further back in history iBike Aero also was capable to display your current CdA. Unfortunately I dont remember whether all the three generations of iBikes had an Aero versions or just Gen III, but what I experienced is that both Aero and Newton+ had been said (marketed) to be able to display an accurate CdA.
Good luck for the third hardware with the same feature.
For me there has been one useful measure of pretty accuracy, which is slope. Velocomp is the best of calculating the instantaneous slope. But wind and Cda data are much more just a nice try than a real feature.
I am also a long time user of iBike Newton and PowerPod. These are much more than power meters. I use PowerTap pedals as an accessory to my PowerPod (to determine my CdA using Isaac), not the other way around. AeroPod will allow me to do this in real time like Newton, but with a Garmin head unit.
Anyone who finds iBike’s CdA estimate inaccurate, keep in mind that the estimate depends on the *difference* between the DFPM and OFPM power readings. It is measuring a small difference between two large numbers. So, even if the AeroPod and PowerTap sensors are not good enough to resolve CdA, they are still good enough for wind speed and power, and also for hill slope as you noted.
You’re correct that AeroPod CdA measurements are based on differences between DFPM and AeroPod readings.
And it’s also true that we introduced our first CdA product 10 years ago. A lot has changed since then.
AeroPod includes a completely new generation of sensors, and also a complete overhaul of signal processing algorithms. Neither of these changes are included in our PowerPod models.
While we have been completely upfront about the science and technology of how we measure CdA, we find it interesting that no other competitor has disclosed their technology or methods. Perhaps that is because they may be infringing on our patents…(for the record, Notio is not infringing…they are a licensee).
Yes, the small hole on the front is what measures wind-speed. With the pitot tube design they get more accurate wind speed (that’s the straw-looking portion of the final design).
thanks Ray,
but even with the wind speed I guess they produce this cDA number with a calculation with wind speed vs distance vs power, right?
I’m just trying to understand how different this cda number is going to be, against the cda number of a wind tunnel.
What are you thoughts on that?
In theory, assuming a straight wind – it should be identical to that of a wind tunnel. Where things can get more complex is cross-wind scenarios.
Remember that ground speed is measured via speed sensor, and then they use wind speed with direct force power meter (not the PowerPod power meter) and your weight to calculate CdA.
At a high level, it’s not super complex. But at a more detailed level getting real-time CdA is not easy, a core reason why some major companies that are in the space have continued to delay it. Part of that challenge is the hardware, and part of it is the software. Velocomp is in a relatively good spot on both just due to being in this space for a decade. Remember, even Notio was/is planning on licensing the Velocomp hardware for their lower end offering (I don’t know if that’s still the plan, but it was as of last fall).
For those of us who have the original PowerPod, will I be able to use the CIQ app? I’ve honestly really struggled to make my PP work with both of my bikes but John and team have been pretty responsive overall and while it’s been frustrating I have to say that when it works, it really is great and the value prop for this thing is pretty awesome.
We have not quite yet figured out how to deal with PowerPod.
We have made a TON of advancements in AeroPod and some of them are, in fact, backwards compatible with PowerPod. That said, we don’t want PowerPod users to have unrealistic expectations. It’s kind of like asking the original iPhone to work as well as today’s iPhone X!
John Hamann wrote: “We have not quite yet figured out how to deal with PowerPod. We have made a TON of advancements in AeroPod and some of them are, in fact, backwards compatible with PowerPod. That said, we don’t want PowerPod users to have unrealistic expectations”.
Advancements are always welcome. But the original PowerPod measures wind speed and hill slope (alas, not as accurately as the AeroPod will). And now that there is a CIQ app that enables a Garmin device to display these data and record them in a .FIT file, couldn’t there be a firmware update to let PowerPod include them in its ANT+ output? I am not asking for an upgrade to increase accuracy or to add new capabilities such as real-time CdA; I am merely asking for it to send its existing output to a head unit that it was originally designed for.
I’m not entirely clear how AeroPod and PowerPod work. I guess they can measure wind speed, acceleration and variation in elevation and they can estimate air density from pressure (and temperature?) data, and ground speed from coupled speed sensor. At this point the PowerPod is still missing Cd*A and coefficient of rolling resistance for proper estimation of resisting power. Where does it get those numbers?
Similarly, I suppose the AirPod needs coupling with a direct force power meter to know an accurate measurement of resisting power. Then, it takes out of that power due to accelerations and elevation gains thanks to its own sensors and finally, having measured air speed, it can calculate Cd*A. Even in this case, I’m not sure how the AirPod is measuring/estimating rolling resistance.
I think that once you provide tyre type and don’t let its pressure go down too much the errors in estimation of rolling resistance are negligible. I still think there might be mistakes due to different road surfaces, especially if going off road.
Following the Kickstarter launch of Powerpod Velocomp then rapidly announced at least one feature which you needed to pay extra for – any ideas if any functionality is going to be hidden behind a paywall this time?
This always seemed a logical thing. The weakness of the powerpod in my mind was that it was essentially making assumptions about aerodynamic resistance. By using a direct force power meter, the calc can work out the assumptions.
A friend for a power pod recently and sent it back within a week. The issue was physical… The air inlet got fouled by the leavings of cows, sheep & farmers on Lake District roads ? and it spent the first 8 minutes of every ride recalibrating. The pitot tube should be less prone to this. I’m willing to be a Guinea pig ?
Backed. One further question for John, who has always provided great customer relations and feedback.
Will the software and broadcasting on the Aeropod allow for Powerpod like usage? So, once the model is dialed in, calibrated by DFPM, and my CdA assessed, could I remove the DFPM and use it as per a PP for general use?
I think this functionality is available in ISAAC at the moment and I’ve used a PP on my time trial bike to very good effect, and also road bikes. I now have a DFPM that I swap regularly. But if calibrated properly, preferably by the phone app, I’d be happy to rely on the numbers from the Aeropod, once position and kit is dialed in – is it ever? ;-)
I find it remarkable that someone finally announced a half wise reasonable price point for 6 dollars of electronics and a 20 dollar differential pressure sensor in a plastic housing. Don’t get me wrong, I’m not arguing with the price point. It’ll likely see a lot of competitors and I’d project competitors < 100 in about 2 years because pitot tubes aren't hard, and proving out an algo's quality over someone elses is going to be pretty much impossible. I did the price analysis and a partial design to see… ya predicting $100 in under 2 years.
Interestingly enough, in cycling community this seems to be undertaking almost equal with space mission and back with so much scientific BS and marketing pathos that is almost funny. In Drone community people create air speed devices with pressure sensors every night in their basements, they have no clue anyone would pay for this more than 100$. Another big community is simple HVAC guys they use those home made devices to check air flow i air ducts. Out of all areas only cycling has amazing premium for it. This will not be 100$ same as we still do not have power meters for 100$. Everyone wants to be insta millionaire…
I suspect Keith knows better than any commentator here that the realities of making a basement project don’t translate to a commercial project.
Commercial projects with sustainable business models require so many more things than a few bits of raw parts stashed together. It also gets into things like support, durability, etc… Not to mention the entire point of a business is to make money.
Drones and cycling are no different. Sure, there’s plenty of people in both sports doing basement things, but ultimately if you want a legit product you spend more. For some applications, basement things are just fine.
It’s actually kinda funny being here at Sea Otter, which is heavily off-road cycling focused: Everyone gets it, because the tolerances, especially for things like fat bikes are so much more important.
Even talking with Jim (of Quarq above) about pricing today, he noted that part of the challenge is figuring out if there’s enough demand. Like any company, if you have low demand, your price goes up. High demand, they can lower prices.
I’d also like to add a major barrier to commercial viability and success… intellectual property. Without doing any digging I would assume velocomp has patented much of the technology that goes into the product (particularly in the application as a cycling tool). There is a reason why some products don’t have competitors (at least for 20 years post patent priority date). Look at the success of powertap’s hub power meter… With such a wildly successful and versatile product, why is it the only dfpm not located in the crank area? Because anyone else who would want to make such a product would have to licence the idea of a hub based pm from saris, thus making it impossible to market at a reasonable price. Sorry to say, but I don’t see any diy’ers able to make a competing product (that uses the same/similar tech) and selling for $100.
Very true -demand is the key. But as with all new things that are ahead of the curve, demand must be cultivated.
One of the problems is that PowerPod is marketed as a cheap power meter. In that light it is arguably not cheap enough. But a data-logging digital inclinometer that connects to your head unit and a network of wireless sensors, and allows you to put your wind speed on Google Earth for $300, is more bang for the buck than a dumb DFPM that is essentially a rotating torque wrench for $800.
“How much would a smartphone cost if the addressable market was the size of the market for a CdA device”?
Yes, but the addressable market includes everybody who would benefit from quantifying (and uploading and sharing) the headwinds they experience and accumulate during bike rides, just as they do now with hill slope and elevation gain. That market is much bigger than the market for a CdA device.
You must hang with a different sort of cyclist than I do. I don’t know anybody who would pay more than a token amount to get wind speed data but I know people who would love to work on their aero-ness.
As others have pointed out getting an accurate CdA is hard.
Maybe Velocomp got it right this time. I hope so. Despite the protestations to the contrary on this thread they misrepresented the capabilities of the Newton in that regard.
1. Design the hardware
2. Co-ordinate with manufacturers on building the hardware
3. QA the manufactured hardware
4. Iterate over 2 and 3 until all the manufacturing snags are worked out
5. Design, write and debug the software for the device
6. Iterate over steps 1 to 5 until you’ve got something that actually works.
7. Design the plastics, the boxes and other manufacturing tooling, as well as end-user software.
8. Iterate over steps 1 through 7 until you have a product you can actually sell to people.
9. Employ people to handle customer logistics and support and train them up
10. Iterate over steps 1 to 9, to build a business that is sustainable and actually generates a return for those who funded all this work.
You’re looking at (easily) five, if not ten, of person-years of skilled work there. How much do you think the living costs (and payroll taxes, etc.) are for that? Now, divide those costs over relatively small production runs (particularly in the earlier stages).
Design and engineering time is not free.
I own a PowerPod and it’s a pretty smart little thing. I used it as a OFPM and it actually produced very close numbers to a DFPM. Very excited to see the CdA aspect of it being developed further – when those metrics are standardised for ANT+ and BLE and widely supported this will be a really *really* useful feature.
Using a dfpm and backing out CdA (btw that’s drag coeffecient times frontal area, not just drag coeffecient) makes some sense but is still difficult. As you saw changing your position drastically changes your CdA and shows how futile it is to try and use a fixed CdA value and airspeed to give a power reading. It will also depend on the clothes you are wearing and things like zipper position on a jacket or jersey. In either case you also need gradient and rolling resistance values to get good results, which makes for a lot of measurement uncertainties that will add up. The faster you ride the better the measurements of CdA will be due to aero drag dominating at high speeds, which is why below 15 mph they don’t try to measure it. For the same reason into the wind must be better than with it. I would expect power from airspeed to be the reverse as the aero part will be much more uncertain than work climbing a gradient — chugging up a steep hill almost all your power is going into climbing, and just the gradient and your speed is needed for the calculation of the major portion of the power.
Your comments are basically spot on. Where we might differ is in how to define what is “drastic”.
Changing ride position drastically has a major effect on CdA. But the key word is drastically; when I go from hoods to TT position, my CdA drops by about .08–enough to cause a significant, 30W difference. But when I go from hoods to drops, my CdA drops by only about .003; difficult to measure, and insignificant with respect to watts. In fact, in my case I learned that the discomfort I experience when in riding in the drops position is not enough to justify my minor improvement in CdA.
Clothing, too, can have a measurable effect on CdA. A TT skin suit drops CdA by about 0.02–an important gain for time trialists.
And yes, on hills, CdA changes have a relatively minor impact on overall watts.
Adding it all up, the simplifying assumption of our prior products that the “default” CdA for your “normal” ride position is constant, is reasonable.
But for those who want to quantify the aero impact of their gear, clothing, and ride position, in the real world, we think AeroPod will be very helpful.
I would like to ask again the question I asked earlier: how do you account for rolling resistance (other than providing a tyre tipe to the software)?
It looks to me that on the tarmac at slow speed (<15 km/h) rolling resistance can be as important as air resistance (and actually higher than aerodynamic resistance for v<10 km/h), but even at high speed on flat terrain rolling resistance can be 10%-15% of the total. Off road and/or with big tyres things are even worse of course.
How does the AeroPod takes these things into account? Are there any limitations in its use (i.e. only tarmac, only road bike etc).
Aerodynamic forces vary as the square of the wind speed, so aerodynamic POWER (power = force x speed) varies as the CUBE of bike speed (assuming ground wind speed is around zero).
Suppose you’re riding at 30 km/h on the flats, in a calm wind, and that your “aero” watts are 180W. If you drop your speed to 15 km/h, your aero watts are ⅛ that amount, only 23W!
Furthermore, in the example above, if riding at 15 km/h, a 20% change in CdA (which would be like going from a hoods to TT position) would produce only a 5W change in aero watts.
This is a long way to explain that, at low bike speeds, sleek aerodynamics are much less important.
Irrespective of bike speed, AeroPod does assume that rolling resistance is constant. So, when conducting CdA tests we recommend that the cyclist pick a road where road surface is the same, and that the cyclist use the same stretch of road when comparing gear/ride position, so that results will be consistent.
Also, if you want to compare CdA results from ride to ride, it’s important that tire pressure is the same.
I have tried a front mount before, but I haven’t found any that is completely straight, so the computer is not centered but moved to the side. It would be feasible if such mount existed…
I don’t mean to press but… At $299 I would have bought it. At $349 I would jump in as well, but at a higher price point the geek in me won’t be as powerful. To be honest I know it won’t be a dramatic change in my trainings or racing as I’m in the mid-front pack and some savings will not give me any more positions.
What I mean is, the price goes up, but I still need to cover this one important fact in order to decide.
Would a long stem mount (long enough to save the bottle, and hard enough so it doesn’t move or vibrate to much) work, or as I’m guessing the data will not be correct as the air can come not clean because the hydration systems could make some turbulence?
Could you make the new combined mount sit lower between the extensions (as per the K-Edge TT). The current one sits up quite high, and for a narrow position, my 810 can run on my wrists! Otherwise, there is still room to mount the PP on the base bar, which is probably where the aeropod will go.
I think I’ve got this correct, but just to make sure – can the AeroPod be used without a head unit?
Context – I’d like to use the AeroPod for aero testing to fine tune my TT position and I’m not as interested in the live data display on a head unit. What I’m hoping to be able to do is ride at the nearby outdoor velodrome for a few minutes in the position I want to test, then download the data to a laptop or phone app to see the CdA results, then make a tweak to equipment or position and ride again for a few minutes before then downloading data and comparing. Will I be able to do this with the AeroPod?
I’m a semi-satisfied user of a Newton with a DFPM and I’d like to believe the claim that this is a new and improved approach to CdA estimates but since similar claims were made for the Newton I’m skeptical right now. I’d need to see solid data validating the device’s performance. With my Newton and DFPM I can tell that there is a difference between the CdA values on my road bike and my TT bike … but that’s not saying much. The CdA data are too noisy to be useful. Also, though my fluid mechanics classes were a long time ago, wouldn’t the device have to measure wind speed as a vector to get accurate results? See for example link to europub.co.uk in which the author claims he improved the Newton’s accuracy during post-exercise processing by considering either measured or imputed wind speed.
In AeroPod we have changed every important element used for CdA measurement: wind sensor, wind port design, signal processing, and calculation algorithms. In our testing, the improvement in CdA stability and resolution is material.
We haven’t tried CdA measurement in strong crosswinds (for example, the 21 km/h cross wind used in the referenced article) and at this time we do not recommend serious CdA testing in those kinds of conditions.
For using the new aeropod an user on the bike Need an Ant+-Speed sensor. The powertap-hubs have built in Speed sensors within their hub. Does anyone know if this kind of a Speed sensor is sufficient for use with aeropod or does it need an additional Ant+-Speed sensor?
It’s a bit hard to tell how the TT mount attaches. Does it come with a clamp for the base bar or does it attach using the bolts that secure the extensions? If the latter there will be compatibility issues that depend on the brand/model of the base bar. Do you have any information about that?
The mount attaches using the bolts that secure the extensions. Our mount has slots, to accommodate different spacings of spacer bolts, and also neoprene washers, to fill any gap caused by non-flat aero bars.
will the aeropod take the cadence data from the powermeter (quarq in my case) to do the pedal stroke analysis in the isaac software or do you need a separate ant cadence sensor?
Hey Folks – quick update: If you missed out on the Kickstarter, you can now also pre-order the unit from Clever Training. Delivery is still slated for July as of this time. Of course, it’s far more expensive than was during the Kickstarter, but that’s the nature of Kickstarter. You can use the DCR coupon code DCR10BTF to save 10% though, and it also gets your free US shipping ($29 internationally). All of which helps support the site here.
Oh, and if you happen to see this message before May 23rd, 2018 at 11:59PM US EST, you can technically save 20% via the CT DCR VIP sale. Details on that here: link to dcrainmaker.com
I’ve noticed they now are saying it’s compatible with Lezyne GPS, is that true? Coming out in a firmware update? I haven’t heard any mention of it from Lezyne
Any update on whether the folks at Wahoo are planning on adding a CdA data field to their units?
I have backed the project and ordered a unit but my only bike computer is an Elemnt Bolt at the moment. Don’t’ really want to have to fork out for a new head unit in addition to the cost of the Aeropod. I’m hoping I can still use the Aerpod for aero testing purposes without a compatible head unit.
I’m curious if the Isaac PC/Mac software or the Powerhouse App have any sort of DRM/user account features that would lock one person to an Aeropod. This seems like a great device for bike shops to purchase a few of and rent them out for people to do A/B equipment and fit testing.
The GoPro compatible mounting interface is versatile enough, but are there plans for a quick-release version (similar to Garmin or Wahoo Elemnt), or an adapter so that a Garmin/GoPro Combo mount is clamped to the handlebar and PowerPod or AeroPod is attached to the underside of it with a 1/4-turn twist? This would make it even more convenient to remove the device for data transfer and battery charging, or to swap bikes.
We require a very solid connection between the sensor and the bike. In our experience the Garmin/Wahoo quick release designs aren’t good enough. GoPro is ubiquitous, and it meets our solid-connection needs.
My Newton is sensitive to minor changes in tilt. The old Newton mounts addressed that by using a custom mount that is quite stable/secure. In my experience GoPro attachments permit some rotation in the mount. Doesn’t that create problems when transferring the AeroPod between bikes? How does the user get the AeroPod in exactly the right position when re-attaching it to a bike?
Thanks. So if the PowerPod mounts should work and if my extensions attach to the base bar with just 1 bolt making them incompatible with the new TT mount is there any down side to using the PowerPod TT mount instead? Or will a location on the extensions mess with the algorithms?
If I understand it correctly, the prototype version of the Connect IQ app displays wind speed, CdA and DFPM power. Will the production version have an optional setting for displaying OFPM power instead?
When the bicycle’s wheel stops rotating, the iBike Newton power meter stops displaying hill slope and wind speed. Does the AeroPod Garmin Connect IQ app also suffer from this limitation?
Correction to my previous comment: When the bicycle’s wheel stops rotating, the Newton power meter continues to display hill slope but stops displaying wind speed. Does the AeroPod Garmin Connect IQ app display hill slope and wind speed when the wheel is not rotating?
When a DFPM is not present, will the AeroPod still operate as a data logger and as a power /slope/ wind indicator without a real time CdA feature?
And when cadence is zero, will it compute and display snapshot CdA, like the the Newton does?
I am curious why AeroPod needs a DFPM to compute CdA when coasting. I would have thought that this would be the condition where the rider-applied power (0 watts) is known with the greatest accuracy.
Interested. Obviously agree about accuracy of power. How do accuracy of instant rolling and mechanical resistance calculations change depending on situation and is there a difference to that depending on whether or not one is coasting?
Yes. But Isaac software includes special tools that allows one to tweak mechanical and rolling resistance and other coefficients to get better correlation with the DFPM data for a whole ride or selection.
In the current version of the real-time CdA estimates for the Newton device and the Isaac software it is unclear how the software models mechanical resistance. The analysis seems to focus on aerodynamic drag (used to calculate CdA) and rolling resistance. Isaac offers to estimate Rolling Resistance based on tire type, road surface and tire pressure. The user can tweak those settings but I do not recall anything to suggest that the software can estimate Crr based on the ride data.
From what I was reading and getting overal feel. Aeropod is not there to test outside for super precise absolute CdA determination, that is something hard to do outside no matter what device tou will use. Instead it is to be use to quickly check changes in CdA on the same road surface. But it can give close enough CdA for average athelete.
In release 1.0 of AeroPod we do not measure Crr. We estimate Crr based on tire type, tire pressure and road surface. Crr is held constant during CdA calculations.
In that case, getting back to Osman’s question, why “2) No”?
On the other hand, this made me wonder why there is no CdA comparison tool that simply uses speed dropoff rate? Too large a change in grade or wind even over a short duration? Or not enough digits in speed measurement?
William wrote: “it is unclear how the software models mechanical resistance”.
Gennaro added: “In my opinion there is no way to get meaningful estimates of rolling resistance from available data”.
John replied: “…we do not measure Crr. We estimate Crr based on tire type, tire pressure and road surface. Crr is held constant during CdA calculations.”
Most likely I am imagining hidden messages in the choice of words, but the distinction between resistance (a force) and Crr (a coefficient) may be deliberate here.
According to that interpretation, “during CdA calculations, rolling resistance is computed from Crr (which is held constant) and an undisclosed number of variables”.
If that were the case, those variables might include, among other things, the roughness of the road surface estimated from the amplitude of the ripples in accelerometer signals.
I don’t think I would read too much into the distinction between resisting forces (eg: rolling resistance) and Crr. The program has to calculate the rolling resistance based on Crr, mass, et cetera. It estimates the value of Crr to use for the calculation.
I’ve always thought it curious that the program apparently has a parameter for mechanical resistance (presumably drivetrain friction) but does not offer any suggestions re: how to guesstimate the value.
I do disagree with the statement that there is no way to get meaningful estimates from available data. I do agree that there is no EASY way to get meaningful/accurate estimates of Crr from cycling data but that is not the same thing.
William wrote: “In the current version of the real-time CdA estimates for the Newton device and the Isaac software it is unclear how the software models mechanical resistance”.
I agree that it is unclear. And it may be deliberately so, but kudos to Velocomp for disclosing as much of their technology as they do. This transparency is way above-and-beyond what is expected or common practice, and it is extremely useful.
In Isaac /Edit Profiles /Advanced, there is a data field Cm that defaults to 1.020. I believe this means that mechanical losses are 2% of the total power (1020 watts into the pedals sends 1000 watts to the road).
Under the “Aero Calcs” heading, there are 3 data fields: Aero, Wind_Scaling and CdA.
Under the “Fric Calcs” heading, there are 4 data fields: Fric, Riding_Tilt, Crr and Cal_Weight. All of these values can be manually tweaked under constraints due to dependencies.
I believe this means that air drag is computed from CdA and at least two other parameters, and rolling resistance is computed from Crr and at least 3 other parameters. I think I understand wind_scaling and riding_tilt, but not Aero and Fric.
The above interpretations are pure speculation on my part, but they are based on the following evidence: when I calculate power from ride data imported from Isaac-generated .csv files, I get power estimates that are close (but not identical) to Isaac’s estimates. My equations are based on the classic model (rolling_resistance = Crr * weight; air_drag = CdA * dynamic_pressure). In other words, my model doesn’t have the extra terms Aero and Fric, so I have some feel for how significant those are. On the other hand, my model has wind yaw. In my opinion, for the purpose of accurately estimating CdA, wind yaw is as critical (if not more) than Aero and Fric. This is also speculation, but the inclusion of wind yaw in the model that has Aero and Fric would likely result in more accurate CdA estimates.
We try to be transparent about the basics of our technology, and we appreciate the fact that Osman has noted that.
Transparency is important because there are a lot of variables that go into CdA measurement, and users who take the time to learn something about them will ultimately get the best accuracy and consistency of results.
There are other companies “out there” who are making noises about CdA measurement. What they have in common is that they say nothing about how they do it. Could that be because doing so would reveal they are infringing on our patents? (For the record, Notio has licensed our patents).
To bad you decided to change some switch last minute and delay shipping by 2 months, I was so happy I will get it in Aug just in time for my TT provincials. Shortly this tool will be useless for this season. October is really last month of riding in Canada, at list on TT bike.
I see from the Velocomp website that the ship date is now listed as September.
This is starting to remind me of the saga with the Brim Brothers and the speedplay-based DFPM.
Brim Brothers missed their promised ship date by years and ultimately never shipped a single power meter. We have shipped tens of thousands of power meters, and I expect AeroPod actual ship date to be missed by less than 30 days.
We have a huge backlog; if you order AeroPod now from our website, it will be September.
We have posted on our Facebook page, on our Kickstarter site, and on our blog the reason for the delay. We’re glad to post it here, too:
“At Eurobike we had lots of people touch and play with our pre-production AeroPods.
One of the very unexpected things we watched people do is attempt to pry off a tab on the side of the unit. Except…it isn’t a removable tab, it is the switch button!
Prying off the button isn’t easy, but it isn’t impossible. And if the button is pried-off it will break the device. We realized that this could turn into a major issue, so in the past few weeks we redesigned the button.
Unfortunately, this design change has delayed our tooling by about a month. So, we now expect to receive parts near the end of August. Hopefully we will begin shipping in late August, but the bulk of orders won’t be delivered until early to mid September.
We know this later than we planned, but we hope you understand why we decided to make this important improvement.”
I’m sure I read somewhere that you were having more success with garmin speed sensors compared to wahoo ? did I imagine this and if not do you have “recommended” sensors and power meters ?
We see “noise” in Wahoo ANT+ speed data that we don’t see in Garmin speed data. We don’t think the Wahoo noise is unacceptable, though we do prefer the Garmin sensor.
The only recommendation we have for power meters is that they measure both legs (as does AeroPod). One-leg power meters have the ability to achieve consistent CdA results with AeroPod, but we aren’t sure they will be good enough for accurate CdA measurement.
I finally got round to mounting my Aeropod on my bike. When I tried to download my Garmin Connect IQ from the forum site my Mac asked what software was required to unzip. I manually selected Winzip Mac but got the message “The document “AeroPod_ConnectIQ_CdA.prg” could not be opened. WinZip Mac cannot open files of this type.”
I’m not sure what to do now. When will the App be available from the Apple Store, as I am familiar with downloading Apps this way to my Mac or iPhone?
You download the ConnectIQ app from the Garmin site: link to apps.garmin.com
The Velocomp forum has instructions for loading onto your bike computer.
I don’t think that non-Garmin head units are supported but I’m not sure.
For Ray, I am very interested in the Aeropod specifically for the real-time CdA analysis. Since your pre-release review, there has been very little recent discussion even on this thread. I was wondering if there is any plan to do a full review of the released Aeropod?
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Garmin-Alphamantis where are you?
I am assuming that this could still be used as a basic powerpod if you don’t have a DFPM?
You don’t have to assume it, it’s been clearly stated that you can ;)
I was an owner of the old Velocomp’s Newton. Was my first “power meter” and serves as an excellent teacher.
By the way, at “has both special hardware inside of it, as well as special hardware” (3rd paragraph) I think it should be hardware/software.
So what about us existing PowerPod owners?
Would love to get beta software upgrade for my powerpod and install the CdA app
But I guess that isn’t really in Velocomp’s interest to sell me the new device?
Second post in two days where I’ve seen someone suggest a manufacturer should give them a new version of a product. Would you expect Ford to buy you a new car when a new model comes out because you bought one of the old ones?
Not to mention that it’s completely technologically unfeasible to do what the AeroPod does with the PowerPod hardware, e.g. measuring wind yaw angle.
To carry on the car analogy, it’s like buying a Tesla and complaining that you can’t fly to Mars in it because SpaceX makes rockets now…
In the past Velocomp has been very good at offering upgrades to previous owners of their products. They would usually have a trade in program of sorts.
This is NOT true that the old hardware cannot measure realtime CDA. This was offered as an upgrade with Newton cycling computers (powerpod’s older brother w/ display and same basic hardware) and has been for years:
link to velocomp-llc.myshopify.com
I have no doubt that this new product is more optimized for the job, but it doesn’t mean the old hardware cannot do it. It would certainly be reasonable to release the software as an upgrade (for a price) to existing users (with the caveat that the data may be x% more error-prone).
They did send a Tesla Roadster towards Mars though…
I think it would be more accurate to say the Velocomp claimed the Newton and Powerpod could be used with a DFPM to measure CdA. When I paired my Newton with a DFPM I did generate numbers that were probably somewhat related to CdA but the results were so unreliable as to be almost useless.
Now they are saying, in effect, that this time they really can measure CdA.
I’d love to see data to support the claims before I drink the Kool Aid aggain.
We did our original CdA work in 2008, with a product called the “iAero”. Its ideas were sound but there were problems with its implementation (mostly sensor quality), that eventually caused us to discontinue the product a year later.
We did leave the 2008 CdA feature in place in firmware, but we did not promote it, and we did zero work to update it.
Last year we began active work on updating our CdA measurement hardware and firmware, and much has changed. If you’d like to see some data, here is a link to some on-the-road measurements performed by one of our beta testers:
link to velocompforum.com
But measuring wind yaw angle is NOT something that the AeroPod does, either.
We have never claimed that AeroPod measures wind yaw angle.
I know. I didn’t mean to imply that a false claim was made. My chronologically out of order comment (sorry) was in response to an April 19 post by Adam: “Not to mention that it’s completely technologically unfeasible to do what the AeroPod does with the PowerPod hardware, e.g. measuring wind yaw angle”.
I was trying to point out that the AeroPod does not measure (or claim to measure) wind yaw angle.
Am I correct to assume that these hardware/firmware changes, which improved the CdA accuracy, resulted from improving the underlying wind speed and power accuracy?
Everything has been improved. That is all we plan to say about the changes.
LOL! Can’t believe the nay-sayers who can’t dream about the possibilities…
Ray, do you have any *opinion* about how this compares to what other companies have announced? From a hardware standpoint I guess if the windspeed sensor is good, the rest is software, right?
I’ve had the idea of using a wind speed meter together with a power meter years ago, although I found out pretty quickly that available smartphone wind sensors for drones/sailing aren’t good enough. The price seems reasonable and I might just finally get that toy :-)
As someone who does computational modeling for a living, I find this very cool. You have to compensate for the 1-2% error from the typical power meters. Your comments about smoothing suggest they are using averaging to help compensate, but presumably the power meter data error has some systematic component (or at least effectively systematic over the relevant time intervals of approximately real-time data) so that simple time averaging won’t just wash the errors out. Throw in some noise on the aerodynamic measurements on top of the power uncertainties, and it must be very challenging to pull a meaningful signal out. I’d love to know how they actually do it, but that’s probably proprietary.
You’ve frequently talked about how you thought companies like Velocomp should do this type of device, but I was always skeptical that it was feasible given the scale of the uncertainties on the inputs and the relatively small range of variations due to aerodynamics for small changes in rider position. If they have accomplished it, I’m impressed! As you say, I would love to see the validation data against some known data like a wind tunnel.
“Note that this PowerPod looking device has both special hardware inside of it, as well as special hardware.”
I think you meant to say has both special hardware inside of it, as well as special software.
I’ve been a beta tester of this. It works, and I’ve got CdA figures from other sources to validate my readings. Incredible value.
I’m going for it. I had the original powerpod but have since upgraded to some p1s. However, I’m planning on a new bike soon so my current bike will be used for commuting. The plan is to use the new pod to get a super accurate cdA which i’ll use in the old pod on the old bike so I can keep track of how my commutes might affect my training.
Plus also use the new pod to get the cdA data on the new (more aero) bike obviously.
I saw the pre-launch kickstarter page last week (via JH@powerpod) and have to say I thought ‘this is it’. It looks like very many boxes have been ticked.
Ray, what are your thoughts on the levels of pricing that the CONSUMER market will bear?
It’s a difficult question as the consumer market is somewhat in its infancy for this type of product/solution.
FWIW I thought the Kickstarter price was spot on to attract lots of takers. I wasn’t so sure in the medium term if $499 would attract too many sales once the initial bump of sales is satisfied.
I think the $299 pricing is very much in line with expectations.
I think the $499-$800 pricing numerous companies have talked about entering at is tricky. At that price point you definitely lower your volume significantly, since it becomes more of a front of the pack tool than a mid to front of the pack triathlete tool*. Also, when you get into the $499-$800 range, you’ve increased the requirement to support accuracy claims. Said differently, consumers expect more of you. Which doesn’t meant at $299 you can deliver crap, but…consumers are willing to put up with more if they save half.
A lot of companies will be watching this carefully. Aeropod has the slight challenge of history and critics that like to see it knocked down (for whatever long ago reasons). So they’re less likely to get some of the cycling media ‘lift’ that other unknown startup entrants might get. It’s somewhat ironic, because even talking to a few aero folks last night at the CIQ event, they’d admit that nobody has better experience in this field [outdoor aero devices] than Velocomp. So we’ll see.
*One could also say a coaching tool used across multiple clients, but I actually don’t think that harnesses the real power of real-time CdA. The point is to be able to use it on race day, not just a few training sessions.
It’s a shame that others have got the headlines, John really knows his onions and on a bumpy English backroad I’ve had repeatable, accurate, verifiable measurements (known baseline).
This will be a great evolution, I note that Aerolab and co are looking at North of $1000. this is proven tech and expertise which has been refined, not a new stab in the dark.
The other day, I wanted to see if a hand position adjustment had changed my helmet choice.
Loaded up, 6 mins (plus 3 for cal) later had my answer.
AeroLab says that they’ll be “well under $1,000” according to the DCR post for the consumer unit, and that still stands.
The power value displayed on your Garmin, is this provided by your DFPM or the AeroPod? I like the idea of knowing wind speed and CdA but would prefer to have the power values from my DFPM displayed and recorded.
Its from your DFPM
Ray, how about estimated left/right power meters, like the PowerTap C1? Would you advise against using those with this?
No need for dual sided, just preferably not single arm (Quarq e.g works fine)
Dave is correct. The estimated left/right part is no biggie since it’s not leveraged here. The total power portion is, which the C1 captures without issue (as does the Power2Max/Quarq/etc options).
A nice development, But…
If a Garmin could record two power streams, could Velocomp write an IQ app to do the deconvolution from PowerPod and DFPM in the head unit? (I own two PowerPods and a DFPM). Their Newton also provided real time CDA using the same model.
EDIT: will the new Isaac software shown mitigate the cost of the CdA add-on cost needed for us PowerPod users currently? That would help a little towards the cost.
For me the biggest problem with the PowerPod was the reliability of the hardware. I had to change 2 units before I finally lost patience and decided to go for a PowerTap hub (which I like a lot). It was a pain sending it to the US and then waiting for the replacement to reach my part of Europe.
So I hope that Velocomp stepped their game up in the hardware department for the new model.
I’m sorry you had problems. We’ve definitely learned some things that will improve reliability of AeroPod, and we’ve already implemented those improvements in current production of PowerPod.
Good to hear that you are improving the reliability.
While I didn’t like the logistics of the replacements I must say that you were always cooperative and answered my inquiries fast. So, thank you for that.
Does Wahoo have any functionality to support 3rd party data fields or add data fields as they go along? That’s one thing I really didn’t think about when I bought my Bolt and would prohibit my from getting a device like this.
They can (and do). I don’t know of the Velocomp folks have approached them. But as an example, the Quarq TyreWiz product also announced today will work with the Wahoo units for recording/showing data from the tire pressure sensor.
We reached out to Wahoo. They informed us that there is an ANT working group for developing CdA standards, and that they would implement the working group standard.
We have no clue when that standard will be finished, so in the mean time we have already developed our own CdA implementation, which will be supported in Garmin Connect IQ, Everysight Raptor, Lezyne bike computers, and PowerHouse app for iOS/Android.
Is the ANT working group, which is developing CdA standards, working on wind speed and wind yaw as well?
They would seem to be reasonable items to have on a spec.
If the CIQ app could access altitude/grade from the Garmin head unit with enough precision, would this also show me mechanical resistance that could then further be broken down into rolling and other resistances using cadence, gear etc? Could be memory lapse but I though some of the other ones promised rolling resistance as well … do those have some sensors etc that this one does not?
Understand that aero is where the big gains are and don’t know whether the other resistances are below or above noise and power meter accuracy level, but would be nice if one could optimize not “just” position but also tire air pressure etc…
It would be better of CIQ app could access altitude/grade from the Aeropod itself (as it’s much more precise than Garmin sensor), or even better – take the rolling resistance parameter from Aeropod directly (it calculates power so it has to estimate rolling resistance anyway).
The grade data showed above is from the AeroPod, not the Edge unit.
backed :)
I’m sure this market area will open up in the next few years – but having something on the market now, however flawed, is better than the promise of something better at a mystery point in the future.
re: the Garmin-Alphamantis, remember how long it took vector to come to market after garmin acquired them and look how long it too to become a mature product you might want to buy.
what I’m saying is that $299 seems like a reasonable gamble to me :)
Going fast. The $299 level is gone. The $349 level is next up.
I didn’t get there quick enough. I could have done the $299 without consulting the wife, but $300 is my “I really got to think about this point”.
At this point I really only pull my son around in a trailer, but I thought it would be cool to see power.
Very excited about this! Currently testing several of the various options out there (3D scans, real world testing (data only), wind tunnel, velodrome, etc). The interest and effort going into aero testing is a great step forward for those of us doing performance modeling and trying to nail down that last piece of high variability data. Getting into the right ballpark (even just two decimals) will do wonders for real world modeling, goal setting, and race planning. This 299 (to 350) price point seems like a really sweet spot so it will be interesting to see how the data compares to options above and to real world modeling.
Thanks for posting this Ray, I just got 349$ option all others were gone, I’m a sucker for new toys, and your video made decision easy, I can see it does work, wondering about 0.000 accuracy but hey looks good, and I’m not waiting for garmin/alphamentis stuff for god knows how long.
Question: is Isaac software included with this hardware? Will Garmin record CDA data to fit file as additional data field and I will need to run some kind of app?
Cheers
Yes, Isaac software is included and yes, our Connect IQ app will record CdA data into the .fit file.
Thanks for answering John!
Last question: how long the battery will last for, and is it rechargeable or replacable?
Keep up the great work!
S.
Battery will last for about 25 hours of ride file recording, assuming you start from a full charge. The battery is rechargeable but is not user replaceable.
Since AeroPod’s Connect IQ app writes CdA data into the .fit file, I assume that it also writes wind speed data. Is my assumption correct?
If so, might Strava (for example) be interested in allowing cyclists to share their headwind, just as they do elevation gain?
Why would there be any connection between writing CdA and writing wind speed? The relative wind speed is included in the ibr data files that Newton and presumably Powerpod record so Isaac could use that data for post-ride analysis but if the CdA calculations are done on the Aeropod the Connect IQ app would not need Wind Speed data.
For years we have written wind speed into our .ibr files, and Isaac allows export into Strava. Don’t know what Strava’s plans are.
You’re correct that the CdA calculation is much more complicated than simply knowing wind speed.
The prototype Connect IQ app (the version reviewed by Ray) displays CdA and wind speed, but doesn’t record them. When John Hamann commented that an upcoming version of the app “will record CdA data into the .fit file” I wanted a confirmation that it will record wind speed, too.
Frankly, I am more excited about wind speed than CdA. For every cyclist with the slightest interest in measuring real time CdA, there are probably at least 100 cyclists who already have a keen interest in measuring (and uploading and sharing) the wind conditions they experience during their bike rides. Most bike rides are neither races nor training sessions, and wind speed (and yaw) are more significant factors affecting bike rides (including races and training sessions), than CdA. They also change much more often and in a wider range.
But in any case, I want to measure wind speed and CdA both; and when I do that with PowerPod I am more content with the accuracy of the wind speed than that of the CdA. Hardware and software improvements from PowerPod to AeroPod may indeed be significant, but wind speed will always be more accurate than CdA. This actuality is dictated by the physics of the situation.
Hi John – how does the aeropod record data to .fit files? I’ve done few rides and while I see the data on the screen and can load them into the Isaac software – I can’t see anything in the .fit file. WKO4 doesn’t show extra data, neither does garmin connect.
Are we still in the testing phase? The CDA ConnectIQ field is not available through the ConnectIQ store and had to be installed manually on the device.
Cheers!
One more question – where does the unit take the HR data from? I see Isaac showing some random HR data, definitely not mine.
The Aeropod does not record FIT file data. It broadcasts data to the Connect IQ app using Ant+ but that app does not (yet?) record data to a FIT file either.
The Aeropod does store data that can be analysed in Isaac but the current version of Isaac does not export to FIT files either.
With the current firmware if you pair a heartrate monitor with the Aeropod the heartrate channel should be just that.
If you do NOT pair a heartrate monitor with Aeropod then the Aeropod’s heartrate channel in Isaac will contain the CdA data recorded by Aeropod. Each “heartrate” value will be equal to the value CdA*250 IIRC. There’s a more detailed explanation at the Velocomp forum.
I’m not certain but I don’t think the Aeropod puts any data into the head unit’s heartrate channel.
Pawel Chalacis: In Isaac / Edit Profiles / Wireless IDs, the number in the data field for HR ID should belong to your heart rate sensor, and the “enabled” light button should be selected. I don’t have experience with AeroPod, but that is how PowerPod records my HR data. It doesn’t record anyone else’s heart rate. When I don’t wear my HRM, Isaac shows no heart rate and the HR column in the csv file has no data in it.
A paid for upgrade is more inline with what I was thinking in my post above.
If I’ve understood what Ray tested correctly, it was updated firmware on an existing Powerpod.
I’d happily pay for that, and it could be similaf to an existing paid for software upgrade that Velocomp offer for powerstroke analysis and after the ride CdA analysis.
So if the existing powerpod device is açcurate enough to capture CdA data, I’d imagine there is a large existing user base who would pay a couple of hundred dollars for a software upgrade.
And by the way I’ve also backed the Kickstarter campaign. I’m massively excited by this whole new area of realtime CdA measurement, and can’t wait to start testing it out.
How cool would it be to be able to have an alert on my head unit when my CdA exceeds a certain threshold during a race? To remind me to get back into proper aero position as I fatigue towards the end the bike leg. It’s the future….
The unit I tested was a modified (harware and software) PowerPod they sent over.
My understanding is there is/was concerns with the existing PowerPod hardware in terms of providing a stable real-time CdA value. Versus data that’s processed afterwards in Issac.
That would be nice, I wonder how far counts as well under?
I was an early PowerPod backer, and am happy to be ‘Backer No. 13’ of the AeroPod. I’m impressed with Velocomp (John’s) technical understanding and achievements.
I’m not as worried as some about absolute accuracy – my rear hub DF power meter can be as much as 7% different to a pedal power meter, and it would still be perfectly acceptable.
I do ultra-endurance bikepacking races. After ‘time in the saddle’, aerodynamics is the most important factor. I know that one feedbag has a minor aero effect, and it feels that two feedbags has a more-than-double effect. I want to test this, comparatively. Is a small hydration / food pack on my back going to slow me down more than a larger seat pack?
I’m really looking forward to a successful product launch!
PS. Thanks Ray, for the positive and confirmatory review!
Notio Konnect & Garmin Alphamantis, so sorry but i’m tired to wait how you jokes to the people, promisses and promisses and pure smoke with a high prices, sorry my stupids first brands, i’m a Hammerhead Karoo user and now supporting this device!
Just backed – first at the $1200 level. Had two buddies that immediately said “I’m in!” and have no doubt I’ll have a fourth soon enough.
Yup, took only a few minutes for another friend to grab the 4th slot. We’re all set and ready to start AeroPodding!
Woohoo! Thank you for your support!
I’m not convinced this product will be useful or actually do what it claims to do. Having used the Newton with a DPFM, I occasionally got some insight into my CdA, but more often than not, it was just a random number generator. I put a lot of time into my testing and tried to be rigorous in my approach, but ultimately, the technology failed. The Newton really doesn’t live up to the the claim of measuring CdA, at least in my experience — at best, it estimated. I don’t regret my purchase of the Newton (and supplied software) because it’s built on a sound understanding of the physics; using the Newton afforded me a unique learning activity but I don’t think you can get qualifiedly good data from a single air-port or piton—it’s just not representative of the bigger picture. The Aeropod may be an improvement, but I’m not convinced: I’ll stick with using the Virtual Elevation (“Chunging it”) module in GoldenCheetah or the regression method. The cost is nil, and the data derived is real and actionable.
That’s the core reason why there’s new hardware for the Aeropod, to get better accuracy.
We have done a lot of work to get from Newton performance to AeroPod–new sensors, new algorithms, new wind port. We are using elite time trialists for testing, who have been wind tunnel measured, to perform comparisons. Their AeroPod data is great.
Going even further back in history iBike Aero also was capable to display your current CdA. Unfortunately I dont remember whether all the three generations of iBikes had an Aero versions or just Gen III, but what I experienced is that both Aero and Newton+ had been said (marketed) to be able to display an accurate CdA.
Good luck for the third hardware with the same feature.
For me there has been one useful measure of pretty accuracy, which is slope. Velocomp is the best of calculating the instantaneous slope. But wind and Cda data are much more just a nice try than a real feature.
I am also a long time user of iBike Newton and PowerPod. These are much more than power meters. I use PowerTap pedals as an accessory to my PowerPod (to determine my CdA using Isaac), not the other way around. AeroPod will allow me to do this in real time like Newton, but with a Garmin head unit.
Anyone who finds iBike’s CdA estimate inaccurate, keep in mind that the estimate depends on the *difference* between the DFPM and OFPM power readings. It is measuring a small difference between two large numbers. So, even if the AeroPod and PowerTap sensors are not good enough to resolve CdA, they are still good enough for wind speed and power, and also for hill slope as you noted.
You’re correct that AeroPod CdA measurements are based on differences between DFPM and AeroPod readings.
And it’s also true that we introduced our first CdA product 10 years ago. A lot has changed since then.
AeroPod includes a completely new generation of sensors, and also a complete overhaul of signal processing algorithms. Neither of these changes are included in our PowerPod models.
While we have been completely upfront about the science and technology of how we measure CdA, we find it interesting that no other competitor has disclosed their technology or methods. Perhaps that is because they may be infringing on our patents…(for the record, Notio is not infringing…they are a licensee).
Hey Ray,
Thanks a lot for this new review.
Is the power pod actually reading wind speed or it’s just an algorithm to get the cda factor from distance/speed vs power?
Guillermo
Yes, the small hole on the front is what measures wind-speed. With the pitot tube design they get more accurate wind speed (that’s the straw-looking portion of the final design).
thanks Ray,
but even with the wind speed I guess they produce this cDA number with a calculation with wind speed vs distance vs power, right?
I’m just trying to understand how different this cda number is going to be, against the cda number of a wind tunnel.
What are you thoughts on that?
In theory, assuming a straight wind – it should be identical to that of a wind tunnel. Where things can get more complex is cross-wind scenarios.
Remember that ground speed is measured via speed sensor, and then they use wind speed with direct force power meter (not the PowerPod power meter) and your weight to calculate CdA.
At a high level, it’s not super complex. But at a more detailed level getting real-time CdA is not easy, a core reason why some major companies that are in the space have continued to delay it. Part of that challenge is the hardware, and part of it is the software. Velocomp is in a relatively good spot on both just due to being in this space for a decade. Remember, even Notio was/is planning on licensing the Velocomp hardware for their lower end offering (I don’t know if that’s still the plan, but it was as of last fall).
For those of us who have the original PowerPod, will I be able to use the CIQ app? I’ve honestly really struggled to make my PP work with both of my bikes but John and team have been pretty responsive overall and while it’s been frustrating I have to say that when it works, it really is great and the value prop for this thing is pretty awesome.
We have not quite yet figured out how to deal with PowerPod.
We have made a TON of advancements in AeroPod and some of them are, in fact, backwards compatible with PowerPod. That said, we don’t want PowerPod users to have unrealistic expectations. It’s kind of like asking the original iPhone to work as well as today’s iPhone X!
I actually really appreciate the forthcoming there.
John Hamann wrote: “We have not quite yet figured out how to deal with PowerPod. We have made a TON of advancements in AeroPod and some of them are, in fact, backwards compatible with PowerPod. That said, we don’t want PowerPod users to have unrealistic expectations”.
Advancements are always welcome. But the original PowerPod measures wind speed and hill slope (alas, not as accurately as the AeroPod will). And now that there is a CIQ app that enables a Garmin device to display these data and record them in a .FIT file, couldn’t there be a firmware update to let PowerPod include them in its ANT+ output? I am not asking for an upgrade to increase accuracy or to add new capabilities such as real-time CdA; I am merely asking for it to send its existing output to a head unit that it was originally designed for.
PowerPod does exactly what is intended to do: send power readings to an ANT+ bike computer.
We might add things to PowerPod at some point in the future, but for now we are going to concentrate on AeroPod.
I’m not entirely clear how AeroPod and PowerPod work. I guess they can measure wind speed, acceleration and variation in elevation and they can estimate air density from pressure (and temperature?) data, and ground speed from coupled speed sensor. At this point the PowerPod is still missing Cd*A and coefficient of rolling resistance for proper estimation of resisting power. Where does it get those numbers?
Similarly, I suppose the AirPod needs coupling with a direct force power meter to know an accurate measurement of resisting power. Then, it takes out of that power due to accelerations and elevation gains thanks to its own sensors and finally, having measured air speed, it can calculate Cd*A. Even in this case, I’m not sure how the AirPod is measuring/estimating rolling resistance.
Am I missing something?
Thanks!
Gennaro
Estimated from your tyre type in Isaac, can be user configured.
Thank you Dave!
I think that once you provide tyre type and don’t let its pressure go down too much the errors in estimation of rolling resistance are negligible. I still think there might be mistakes due to different road surfaces, especially if going off road.
Following the Kickstarter launch of Powerpod Velocomp then rapidly announced at least one feature which you needed to pay extra for – any ideas if any functionality is going to be hidden behind a paywall this time?
AeroPod will have all current, extra firmware features pre-installed. It will be the fullest-featured power meter we have ever made.
Which feature is this ?
AeroPod will include, as standard features, CdA, PowerStroke, and GPS upgrades, all of which are optional on prior products.
This always seemed a logical thing. The weakness of the powerpod in my mind was that it was essentially making assumptions about aerodynamic resistance. By using a direct force power meter, the calc can work out the assumptions.
A friend for a power pod recently and sent it back within a week. The issue was physical… The air inlet got fouled by the leavings of cows, sheep & farmers on Lake District roads ? and it spent the first 8 minutes of every ride recalibrating. The pitot tube should be less prone to this. I’m willing to be a Guinea pig ?
Backed. One further question for John, who has always provided great customer relations and feedback.
Will the software and broadcasting on the Aeropod allow for Powerpod like usage? So, once the model is dialed in, calibrated by DFPM, and my CdA assessed, could I remove the DFPM and use it as per a PP for general use?
I think this functionality is available in ISAAC at the moment and I’ve used a PP on my time trial bike to very good effect, and also road bikes. I now have a DFPM that I swap regularly. But if calibrated properly, preferably by the phone app, I’d be happy to rely on the numbers from the Aeropod, once position and kit is dialed in – is it ever? ;-)
Yes, if you dial in your AeroPod, it will function very well as a stand-alone power meter.
I find it remarkable that someone finally announced a half wise reasonable price point for 6 dollars of electronics and a 20 dollar differential pressure sensor in a plastic housing. Don’t get me wrong, I’m not arguing with the price point. It’ll likely see a lot of competitors and I’d project competitors < 100 in about 2 years because pitot tubes aren't hard, and proving out an algo's quality over someone elses is going to be pretty much impossible. I did the price analysis and a partial design to see… ya predicting $100 in under 2 years.
Interestingly enough, in cycling community this seems to be undertaking almost equal with space mission and back with so much scientific BS and marketing pathos that is almost funny. In Drone community people create air speed devices with pressure sensors every night in their basements, they have no clue anyone would pay for this more than 100$. Another big community is simple HVAC guys they use those home made devices to check air flow i air ducts. Out of all areas only cycling has amazing premium for it. This will not be 100$ same as we still do not have power meters for 100$. Everyone wants to be insta millionaire…
I suspect Keith knows better than any commentator here that the realities of making a basement project don’t translate to a commercial project.
Commercial projects with sustainable business models require so many more things than a few bits of raw parts stashed together. It also gets into things like support, durability, etc… Not to mention the entire point of a business is to make money.
Drones and cycling are no different. Sure, there’s plenty of people in both sports doing basement things, but ultimately if you want a legit product you spend more. For some applications, basement things are just fine.
It’s actually kinda funny being here at Sea Otter, which is heavily off-road cycling focused: Everyone gets it, because the tolerances, especially for things like fat bikes are so much more important.
Even talking with Jim (of Quarq above) about pricing today, he noted that part of the challenge is figuring out if there’s enough demand. Like any company, if you have low demand, your price goes up. High demand, they can lower prices.
I’d also like to add a major barrier to commercial viability and success… intellectual property. Without doing any digging I would assume velocomp has patented much of the technology that goes into the product (particularly in the application as a cycling tool). There is a reason why some products don’t have competitors (at least for 20 years post patent priority date). Look at the success of powertap’s hub power meter… With such a wildly successful and versatile product, why is it the only dfpm not located in the crank area? Because anyone else who would want to make such a product would have to licence the idea of a hub based pm from saris, thus making it impossible to market at a reasonable price. Sorry to say, but I don’t see any diy’ers able to make a competing product (that uses the same/similar tech) and selling for $100.
Ahh…if only your hardware costs were accurate! Would have long ago introduced a $100 power meter.
And remember, it’s not just about hardware costs; the firmware, software, and algorithms are expensive to develop and support.
Finally, volumes are important too. How much would a smartphone cost if the addressable market was the size of the market for a CdA device?
Correct. In fact, we have very fundamental patents in opposing force measurement.
Very true -demand is the key. But as with all new things that are ahead of the curve, demand must be cultivated.
One of the problems is that PowerPod is marketed as a cheap power meter. In that light it is arguably not cheap enough. But a data-logging digital inclinometer that connects to your head unit and a network of wireless sensors, and allows you to put your wind speed on Google Earth for $300, is more bang for the buck than a dumb DFPM that is essentially a rotating torque wrench for $800.
“…a dumb DFPM that is essentially a rotating torque wrench for $800″…wow, just remember, folks, he said it, not us!!! :-)
“How much would a smartphone cost if the addressable market was the size of the market for a CdA device”?
Yes, but the addressable market includes everybody who would benefit from quantifying (and uploading and sharing) the headwinds they experience and accumulate during bike rides, just as they do now with hill slope and elevation gain. That market is much bigger than the market for a CdA device.
You must hang with a different sort of cyclist than I do. I don’t know anybody who would pay more than a token amount to get wind speed data but I know people who would love to work on their aero-ness.
As others have pointed out getting an accurate CdA is hard.
Maybe Velocomp got it right this time. I hope so. Despite the protestations to the contrary on this thread they misrepresented the capabilities of the Newton in that regard.
Maybe you are right. There was a time when nobody would pay more than a token to get elevation data. They would laugh at me if I suggested it.
Have you added in the cost of human time to:
1. Design the hardware
2. Co-ordinate with manufacturers on building the hardware
3. QA the manufactured hardware
4. Iterate over 2 and 3 until all the manufacturing snags are worked out
5. Design, write and debug the software for the device
6. Iterate over steps 1 to 5 until you’ve got something that actually works.
7. Design the plastics, the boxes and other manufacturing tooling, as well as end-user software.
8. Iterate over steps 1 through 7 until you have a product you can actually sell to people.
9. Employ people to handle customer logistics and support and train them up
10. Iterate over steps 1 to 9, to build a business that is sustainable and actually generates a return for those who funded all this work.
You’re looking at (easily) five, if not ten, of person-years of skilled work there. How much do you think the living costs (and payroll taxes, etc.) are for that? Now, divide those costs over relatively small production runs (particularly in the earlier stages).
Design and engineering time is not free.
I own a PowerPod and it’s a pretty smart little thing. I used it as a OFPM and it actually produced very close numbers to a DFPM. Very excited to see the CdA aspect of it being developed further – when those metrics are standardised for ANT+ and BLE and widely supported this will be a really *really* useful feature.
Congrats Velocomp.
Using a dfpm and backing out CdA (btw that’s drag coeffecient times frontal area, not just drag coeffecient) makes some sense but is still difficult. As you saw changing your position drastically changes your CdA and shows how futile it is to try and use a fixed CdA value and airspeed to give a power reading. It will also depend on the clothes you are wearing and things like zipper position on a jacket or jersey. In either case you also need gradient and rolling resistance values to get good results, which makes for a lot of measurement uncertainties that will add up. The faster you ride the better the measurements of CdA will be due to aero drag dominating at high speeds, which is why below 15 mph they don’t try to measure it. For the same reason into the wind must be better than with it. I would expect power from airspeed to be the reverse as the aero part will be much more uncertain than work climbing a gradient — chugging up a steep hill almost all your power is going into climbing, and just the gradient and your speed is needed for the calculation of the major portion of the power.
Your comments are basically spot on. Where we might differ is in how to define what is “drastic”.
Changing ride position drastically has a major effect on CdA. But the key word is drastically; when I go from hoods to TT position, my CdA drops by about .08–enough to cause a significant, 30W difference. But when I go from hoods to drops, my CdA drops by only about .003; difficult to measure, and insignificant with respect to watts. In fact, in my case I learned that the discomfort I experience when in riding in the drops position is not enough to justify my minor improvement in CdA.
Clothing, too, can have a measurable effect on CdA. A TT skin suit drops CdA by about 0.02–an important gain for time trialists.
And yes, on hills, CdA changes have a relatively minor impact on overall watts.
Adding it all up, the simplifying assumption of our prior products that the “default” CdA for your “normal” ride position is constant, is reasonable.
But for those who want to quantify the aero impact of their gear, clothing, and ride position, in the real world, we think AeroPod will be very helpful.
I would like to ask again the question I asked earlier: how do you account for rolling resistance (other than providing a tyre tipe to the software)?
It looks to me that on the tarmac at slow speed (<15 km/h) rolling resistance can be as important as air resistance (and actually higher than aerodynamic resistance for v<10 km/h), but even at high speed on flat terrain rolling resistance can be 10%-15% of the total. Off road and/or with big tyres things are even worse of course.
How does the AeroPod takes these things into account? Are there any limitations in its use (i.e. only tarmac, only road bike etc).
Thanks!
Gennaro
Sorry, I missed your question when it was posted.
Aerodynamic forces vary as the square of the wind speed, so aerodynamic POWER (power = force x speed) varies as the CUBE of bike speed (assuming ground wind speed is around zero).
Suppose you’re riding at 30 km/h on the flats, in a calm wind, and that your “aero” watts are 180W. If you drop your speed to 15 km/h, your aero watts are ⅛ that amount, only 23W!
Furthermore, in the example above, if riding at 15 km/h, a 20% change in CdA (which would be like going from a hoods to TT position) would produce only a 5W change in aero watts.
This is a long way to explain that, at low bike speeds, sleek aerodynamics are much less important.
Irrespective of bike speed, AeroPod does assume that rolling resistance is constant. So, when conducting CdA tests we recommend that the cyclist pick a road where road surface is the same, and that the cyclist use the same stretch of road when comparing gear/ride position, so that results will be consistent.
Also, if you want to compare CdA results from ride to ride, it’s important that tire pressure is the same.
What worries me is TT mounts, specially taking about front mount hydration systems.
For example I use the profile design fc35 (link to i.ytimg.com). And I don’t really find any way to install Aeropod with it.
John, I would love to read your thoughts about this
Another image
link to bikeboard.at
I have tried a front mount before, but I haven’t found any that is completely straight, so the computer is not centered but moved to the side. It would be feasible if such mount existed…
We’re working on some new TT mount systems. Details to follow soon…
Thanks John.
I don’t mean to press but… At $299 I would have bought it. At $349 I would jump in as well, but at a higher price point the geek in me won’t be as powerful. To be honest I know it won’t be a dramatic change in my trainings or racing as I’m in the mid-front pack and some savings will not give me any more positions.
What I mean is, the price goes up, but I still need to cover this one important fact in order to decide.
Would a long stem mount (long enough to save the bottle, and hard enough so it doesn’t move or vibrate to much) work, or as I’m guessing the data will not be correct as the air can come not clean because the hydration systems could make some turbulence?
Could you make the new combined mount sit lower between the extensions (as per the K-Edge TT). The current one sits up quite high, and for a narrow position, my 810 can run on my wrists! Otherwise, there is still room to mount the PP on the base bar, which is probably where the aeropod will go.
We are working on a completely new mount system for TT bikes. Stay tuned!
I think I’ve got this correct, but just to make sure – can the AeroPod be used without a head unit?
Context – I’d like to use the AeroPod for aero testing to fine tune my TT position and I’m not as interested in the live data display on a head unit. What I’m hoping to be able to do is ride at the nearby outdoor velodrome for a few minutes in the position I want to test, then download the data to a laptop or phone app to see the CdA results, then make a tweak to equipment or position and ride again for a few minutes before then downloading data and comparing. Will I be able to do this with the AeroPod?
Isaac software includes an “Analyze CdA…” function that will allow you to do just what you want.
I’m a semi-satisfied user of a Newton with a DFPM and I’d like to believe the claim that this is a new and improved approach to CdA estimates but since similar claims were made for the Newton I’m skeptical right now. I’d need to see solid data validating the device’s performance. With my Newton and DFPM I can tell that there is a difference between the CdA values on my road bike and my TT bike … but that’s not saying much. The CdA data are too noisy to be useful. Also, though my fluid mechanics classes were a long time ago, wouldn’t the device have to measure wind speed as a vector to get accurate results? See for example link to europub.co.uk in which the author claims he improved the Newton’s accuracy during post-exercise processing by considering either measured or imputed wind speed.
The CdA stuff used in Newton was created in 2008.
In AeroPod we have changed every important element used for CdA measurement: wind sensor, wind port design, signal processing, and calculation algorithms. In our testing, the improvement in CdA stability and resolution is material.
We haven’t tried CdA measurement in strong crosswinds (for example, the 21 km/h cross wind used in the referenced article) and at this time we do not recommend serious CdA testing in those kinds of conditions.
For using the new aeropod an user on the bike Need an Ant+-Speed sensor. The powertap-hubs have built in Speed sensors within their hub. Does anyone know if this kind of a Speed sensor is sufficient for use with aeropod or does it need an additional Ant+-Speed sensor?
We will check this and report back.
Do you have checked it in the meantime?
May i use the aeropod with the speed sensor of the powertap hub?
We are adding PT hub speed sensor to AeroPod capabilities.
On our Kickstarter campaign we just posted an update, showing a new TT under-the-aero-bars mount that we will be shipping with AeroPod.
link to kickstarter.com
It’s a bit hard to tell how the TT mount attaches. Does it come with a clamp for the base bar or does it attach using the bolts that secure the extensions? If the latter there will be compatibility issues that depend on the brand/model of the base bar. Do you have any information about that?
The mount attaches using the bolts that secure the extensions. Our mount has slots, to accommodate different spacings of spacer bolts, and also neoprene washers, to fill any gap caused by non-flat aero bars.
what about TT bikes that have integrated water bottles in front? Is it a problem if the sensor is very close to something else?
One of the things we’ve been asked about is validation.
We have produced a brief presentation regarding results from one of our beta testers, available here:
link to velocompforum.com
will the aeropod take the cadence data from the powermeter (quarq in my case) to do the pedal stroke analysis in the isaac software or do you need a separate ant cadence sensor?
Yes, AeroPod “reads” cadence signals from your DFPM.
We made a short video showing how Raptor glasses display AeroPod CdA data.
Check it out!
link to youtu.be
Hey Folks – quick update: If you missed out on the Kickstarter, you can now also pre-order the unit from Clever Training. Delivery is still slated for July as of this time. Of course, it’s far more expensive than was during the Kickstarter, but that’s the nature of Kickstarter. You can use the DCR coupon code DCR10BTF to save 10% though, and it also gets your free US shipping ($29 internationally). All of which helps support the site here.
Product pre-order page: link to clevertraining.com
Oh, and if you happen to see this message before May 23rd, 2018 at 11:59PM US EST, you can technically save 20% via the CT DCR VIP sale. Details on that here: link to dcrainmaker.com
I’ve noticed they now are saying it’s compatible with Lezyne GPS, is that true? Coming out in a firmware update? I haven’t heard any mention of it from Lezyne
We have spoken to the folks at Lezyne and they are promising a firmware update that will add AeroPod CdA display to their GPS bike computers.
Any update on whether the folks at Wahoo are planning on adding a CdA data field to their units?
I have backed the project and ordered a unit but my only bike computer is an Elemnt Bolt at the moment. Don’t’ really want to have to fork out for a new head unit in addition to the cost of the Aeropod. I’m hoping I can still use the Aerpod for aero testing purposes without a compatible head unit.
At this point it’s up to them.
I think a “write-in” campaign from backers might encourage Wahoo to move ahead!
I’m on it!
Do you have a contact email for them other than the online form?
Thanks
It looks like there may be some trademark issues. I don’t know who was first to start using the name:
link to bikerumor.com
I’m curious if the Isaac PC/Mac software or the Powerhouse App have any sort of DRM/user account features that would lock one person to an Aeropod. This seems like a great device for bike shops to purchase a few of and rent them out for people to do A/B equipment and fit testing.
You can name ride files in Isaac, customizing them to the name of the person.
The GoPro compatible mounting interface is versatile enough, but are there plans for a quick-release version (similar to Garmin or Wahoo Elemnt), or an adapter so that a Garmin/GoPro Combo mount is clamped to the handlebar and PowerPod or AeroPod is attached to the underside of it with a 1/4-turn twist? This would make it even more convenient to remove the device for data transfer and battery charging, or to swap bikes.
We require a very solid connection between the sensor and the bike. In our experience the Garmin/Wahoo quick release designs aren’t good enough. GoPro is ubiquitous, and it meets our solid-connection needs.
Thank you, John. This makes sense.
My Newton is sensitive to minor changes in tilt. The old Newton mounts addressed that by using a custom mount that is quite stable/secure. In my experience GoPro attachments permit some rotation in the mount. Doesn’t that create problems when transferring the AeroPod between bikes? How does the user get the AeroPod in exactly the right position when re-attaching it to a bike?
All Velocomp devices are sensitive to changes in tilt–that is one way we measure power on hills!
We have stops on the AeroPod that position its angle properly on its mount; if you then tighten AeroPod to the mount it won’t rotate.
Also, we’ve implemented an improvement in AeroPod that corrects tilt variations in 90 seconds–not the 8 minutes required by Newton.
That sounds like the same system as the PowerPod. Does that mean the PowerPod mounts will work with AeroPod?
Yes
Thanks. So if the PowerPod mounts should work and if my extensions attach to the base bar with just 1 bolt making them incompatible with the new TT mount is there any down side to using the PowerPod TT mount instead? Or will a location on the extensions mess with the algorithms?
Sorry, but I do not understand your question. Please email me at jhamann@velocomp.com
If I understand it correctly, the prototype version of the Connect IQ app displays wind speed, CdA and DFPM power. Will the production version have an optional setting for displaying OFPM power instead?
No.
When will the Connect IQ app be available to download?
The app is available now. You can find it, linked, in item 3), here:
link to velocompforum.com
Got it, thx. I was looking in the Garmin Connect IQ Store and couldn’t find it there.
When the bicycle’s wheel stops rotating, the iBike Newton power meter stops displaying hill slope and wind speed. Does the AeroPod Garmin Connect IQ app also suffer from this limitation?
Correction to my previous comment: When the bicycle’s wheel stops rotating, the Newton power meter continues to display hill slope but stops displaying wind speed. Does the AeroPod Garmin Connect IQ app display hill slope and wind speed when the wheel is not rotating?
The Connect IQ app displays hill slope when the bike as at rest. A wind speed number shown but it has no meaning.
When a DFPM is not present, will the AeroPod still operate as a data logger and as a power /slope/ wind indicator without a real time CdA feature?
And when cadence is zero, will it compute and display snapshot CdA, like the the Newton does?
1) Yes
2) No
I am curious why AeroPod needs a DFPM to compute CdA when coasting. I would have thought that this would be the condition where the rider-applied power (0 watts) is known with the greatest accuracy.
Interested. Obviously agree about accuracy of power. How do accuracy of instant rolling and mechanical resistance calculations change depending on situation and is there a difference to that depending on whether or not one is coasting?
I think you need to enter rolling resistance manually, it is value set in software, not something aeropod will be able to calculate.
Yes. But Isaac software includes special tools that allows one to tweak mechanical and rolling resistance and other coefficients to get better correlation with the DFPM data for a whole ride or selection.
In the current version of the real-time CdA estimates for the Newton device and the Isaac software it is unclear how the software models mechanical resistance. The analysis seems to focus on aerodynamic drag (used to calculate CdA) and rolling resistance. Isaac offers to estimate Rolling Resistance based on tire type, road surface and tire pressure. The user can tweak those settings but I do not recall anything to suggest that the software can estimate Crr based on the ride data.
From what I was reading and getting overal feel. Aeropod is not there to test outside for super precise absolute CdA determination, that is something hard to do outside no matter what device tou will use. Instead it is to be use to quickly check changes in CdA on the same road surface. But it can give close enough CdA for average athelete.
In my opinion there is no way to get meaningful estimates of rolling resistance from available data.
In release 1.0 of AeroPod we do not measure Crr. We estimate Crr based on tire type, tire pressure and road surface. Crr is held constant during CdA calculations.
Thanks, good to learn.
In that case, getting back to Osman’s question, why “2) No”?
On the other hand, this made me wonder why there is no CdA comparison tool that simply uses speed dropoff rate? Too large a change in grade or wind even over a short duration? Or not enough digits in speed measurement?
William wrote: “it is unclear how the software models mechanical resistance”.
Gennaro added: “In my opinion there is no way to get meaningful estimates of rolling resistance from available data”.
John replied: “…we do not measure Crr. We estimate Crr based on tire type, tire pressure and road surface. Crr is held constant during CdA calculations.”
Most likely I am imagining hidden messages in the choice of words, but the distinction between resistance (a force) and Crr (a coefficient) may be deliberate here.
According to that interpretation, “during CdA calculations, rolling resistance is computed from Crr (which is held constant) and an undisclosed number of variables”.
If that were the case, those variables might include, among other things, the roughness of the road surface estimated from the amplitude of the ripples in accelerometer signals.
I don’t think I would read too much into the distinction between resisting forces (eg: rolling resistance) and Crr. The program has to calculate the rolling resistance based on Crr, mass, et cetera. It estimates the value of Crr to use for the calculation.
I’ve always thought it curious that the program apparently has a parameter for mechanical resistance (presumably drivetrain friction) but does not offer any suggestions re: how to guesstimate the value.
I do disagree with the statement that there is no way to get meaningful estimates from available data. I do agree that there is no EASY way to get meaningful/accurate estimates of Crr from cycling data but that is not the same thing.
William wrote: “In the current version of the real-time CdA estimates for the Newton device and the Isaac software it is unclear how the software models mechanical resistance”.
I agree that it is unclear. And it may be deliberately so, but kudos to Velocomp for disclosing as much of their technology as they do. This transparency is way above-and-beyond what is expected or common practice, and it is extremely useful.
In Isaac /Edit Profiles /Advanced, there is a data field Cm that defaults to 1.020. I believe this means that mechanical losses are 2% of the total power (1020 watts into the pedals sends 1000 watts to the road).
Under the “Aero Calcs” heading, there are 3 data fields: Aero, Wind_Scaling and CdA.
Under the “Fric Calcs” heading, there are 4 data fields: Fric, Riding_Tilt, Crr and Cal_Weight. All of these values can be manually tweaked under constraints due to dependencies.
I believe this means that air drag is computed from CdA and at least two other parameters, and rolling resistance is computed from Crr and at least 3 other parameters. I think I understand wind_scaling and riding_tilt, but not Aero and Fric.
The above interpretations are pure speculation on my part, but they are based on the following evidence: when I calculate power from ride data imported from Isaac-generated .csv files, I get power estimates that are close (but not identical) to Isaac’s estimates. My equations are based on the classic model (rolling_resistance = Crr * weight; air_drag = CdA * dynamic_pressure). In other words, my model doesn’t have the extra terms Aero and Fric, so I have some feel for how significant those are. On the other hand, my model has wind yaw. In my opinion, for the purpose of accurately estimating CdA, wind yaw is as critical (if not more) than Aero and Fric. This is also speculation, but the inclusion of wind yaw in the model that has Aero and Fric would likely result in more accurate CdA estimates.
We try to be transparent about the basics of our technology, and we appreciate the fact that Osman has noted that.
Transparency is important because there are a lot of variables that go into CdA measurement, and users who take the time to learn something about them will ultimately get the best accuracy and consistency of results.
There are other companies “out there” who are making noises about CdA measurement. What they have in common is that they say nothing about how they do it. Could that be because doing so would reveal they are infringing on our patents? (For the record, Notio has licensed our patents).
To bad you decided to change some switch last minute and delay shipping by 2 months, I was so happy I will get it in Aug just in time for my TT provincials. Shortly this tool will be useless for this season. October is really last month of riding in Canada, at list on TT bike.
Please email me at jhamann@velocomp.com
I see from the Velocomp website that the ship date is now listed as September.
This is starting to remind me of the saga with the Brim Brothers and the speedplay-based DFPM.
Brim Brothers missed their promised ship date by years and ultimately never shipped a single power meter. We have shipped tens of thousands of power meters, and I expect AeroPod actual ship date to be missed by less than 30 days.
We have a huge backlog; if you order AeroPod now from our website, it will be September.
We have posted on our Facebook page, on our Kickstarter site, and on our blog the reason for the delay. We’re glad to post it here, too:
“At Eurobike we had lots of people touch and play with our pre-production AeroPods.
One of the very unexpected things we watched people do is attempt to pry off a tab on the side of the unit. Except…it isn’t a removable tab, it is the switch button!
Prying off the button isn’t easy, but it isn’t impossible. And if the button is pried-off it will break the device. We realized that this could turn into a major issue, so in the past few weeks we redesigned the button.
Unfortunately, this design change has delayed our tooling by about a month. So, we now expect to receive parts near the end of August. Hopefully we will begin shipping in late August, but the bulk of orders won’t be delivered until early to mid September.
We know this later than we planned, but we hope you understand why we decided to make this important improvement.”
I’m sure I read somewhere that you were having more success with garmin speed sensors compared to wahoo ? did I imagine this and if not do you have “recommended” sensors and power meters ?
We see “noise” in Wahoo ANT+ speed data that we don’t see in Garmin speed data. We don’t think the Wahoo noise is unacceptable, though we do prefer the Garmin sensor.
The only recommendation we have for power meters is that they measure both legs (as does AeroPod). One-leg power meters have the ability to achieve consistent CdA results with AeroPod, but we aren’t sure they will be good enough for accurate CdA measurement.
:)
I finally got round to mounting my Aeropod on my bike. When I tried to download my Garmin Connect IQ from the forum site my Mac asked what software was required to unzip. I manually selected Winzip Mac but got the message “The document “AeroPod_ConnectIQ_CdA.prg” could not be opened. WinZip Mac cannot open files of this type.”
I’m not sure what to do now. When will the App be available from the Apple Store, as I am familiar with downloading Apps this way to my Mac or iPhone?
You download the ConnectIQ app from the Garmin site:
link to apps.garmin.com
The Velocomp forum has instructions for loading onto your bike computer.
I don’t think that non-Garmin head units are supported but I’m not sure.
For Ray, I am very interested in the Aeropod specifically for the real-time CdA analysis. Since your pre-release review, there has been very little recent discussion even on this thread. I was wondering if there is any plan to do a full review of the released Aeropod?
Carl
+1
Interested also in seeing if other computers other than Garmin would be supported