How hard would it be to add an anemometer to a cycling computer?
05-05-14, 01:45 PM
#26
Senior Member
Join Date: Jul 2013
Location: Missouri
Posts: 2,690
Bikes: Giant Propel, Cannondale SuperX, Univega Alpina Ultima
Mentioned: 5 Post(s)
Tagged: 0 Thread(s)
Quoted: 672 Post(s)
Liked 417 Times
in
249 Posts
That's a wind gauge. 
I'm thinking you could have sensors on all four corners of the computer and an algorithm that applied the actual bike speed and determined the actual direction and strength of the wind as well as the effective direction and strength in combination with the motion of the bike.
I'm thinking you could have sensors on all four corners of the computer and an algorithm that applied the actual bike speed and determined the actual direction and strength of the wind as well as the effective direction and strength in combination with the motion of the bike.
__________________
Formerly fastest rider in the grupetto, currently slowest guy in the peloton
Formerly fastest rider in the grupetto, currently slowest guy in the peloton
05-05-14, 01:58 PM
#27
Senior Member
Thread Starter
Join Date: Dec 2009
Location: Houston, TX
Posts: 28,682
Bikes: 1990 Romic Reynolds 531 custom build, Merlin Works CR Ti custom build, super light Workswell 066 custom build
Mentioned: 109 Post(s)
Tagged: 1 Thread(s)
Quoted: 6556 Post(s)
Likes: 0
Liked 58 Times
in
36 Posts
Would you really need more than one front facing sensor? If the computer knows ground speed it should be able to use a simple algorithm to calculate wind speed. Direction would be harder but a 30mph measured wind speed and 20mph bike speed would mean an effective 10mph headwind which might be all that really matters. Of course, maybe an ANT+ helmet mounted sensor would provide more info. Seems it would need to be out of the way of your body though for any accurate recording.
05-05-14, 02:03 PM
#28
Senior Member
Join Date: Apr 2007
Location: Tulsa OK
Posts: 2,076
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 63 Post(s)
Likes: 0
Liked 0 Times
in
0 Posts
How do I lie about the headwind if I have data proving that it was 10mph instead of the 20+mph I told everyone.
05-05-14, 02:31 PM
#29
Uber Goober
Maybe somebody's got it worked out, but I'm not aware of any way to calculate drag or power for a quartering wind.
__________________
"be careful this rando stuff is addictive and dan's the 'pusher'."
"be careful this rando stuff is addictive and dan's the 'pusher'."
05-05-14, 02:40 PM
#30
pan y agua
Join Date: Aug 2005
Location: Jacksonville
Posts: 31,304
Bikes: Willier Zero 7; Merlin Extralight; Calfee Dragonfly tandem, Calfee Adventure tandem; Cervelo P2; Motebecane Ti Fly 29er; Motebecanne Phantom Cross; Schwinn Paramount Track bike
Mentioned: 17 Post(s)
Tagged: 0 Thread(s)
Quoted: 1447 Post(s)
Liked 727 Times
in
372 Posts
The Ibike people apparently do. There are a number of limitations to the Ibike, but if you get it calibrated correctly, it apparently is fairly accurate, which it couldn't be unless it could figure that out.
__________________
You could fall off a cliff and die.
You could get lost and die.
You could hit a tree and die.
OR YOU COULD STAY HOME AND FALL OFF THE COUCH AND DIE.
You could fall off a cliff and die.
You could get lost and die.
You could hit a tree and die.
OR YOU COULD STAY HOME AND FALL OFF THE COUCH AND DIE.
05-05-14, 05:46 PM
#34
Senior Member
Join Date: Nov 2013
Location: KS
Posts: 90
Bikes: Specialized Allez
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 3 Post(s)
Likes: 0
Liked 0 Times
in
0 Posts
1. Buy a shirt that says Anemometer, make one if none available.
2. Put shirt on.
3. If you don't know what to do next, return to step one.
2. Put shirt on.
3. If you don't know what to do next, return to step one.
05-05-14, 06:33 PM
#35
Uber Goober
I'm not so sure about that. If you look at the comparison charts on the Ibike website, you'll see stretches where there are significant differences, other places where it's right on. What is different where the curves don't match? Maybe the rider is drafting, maybe the rider is in the drops, or maybe that's where crosswinds were throwing the results off. I'm also assuming that those graphs are the best that it can do, not average results, and not the worst results they ever got.
__________________
"be careful this rando stuff is addictive and dan's the 'pusher'."
"be careful this rando stuff is addictive and dan's the 'pusher'."
05-05-14, 07:11 PM
#36
Senior Member
Join Date: Oct 2013
Location: Oahu, HI
Posts: 1,396
Bikes: 89 Paramount OS 84 Fuji Touring Series III New! 2013 Focus Izalco Ergoride
Mentioned: 2 Post(s)
Tagged: 0 Thread(s)
Quoted: 285 Post(s)
Likes: 0
Liked 74 Times
in
54 Posts
I can see if the relative wind is say +/- 45 degrees of front, you could get an OK estimate and compute true wind, but if the relative wind is outside of that I think it would be hard without additional sensors, and then you have the problem of the local airstream distorting. As far as using reported weather, local topography makes that of limited value I would think.
scott s.
.
scott s.
.
05-06-14, 08:15 AM
#38
pan y agua
Join Date: Aug 2005
Location: Jacksonville
Posts: 31,304
Bikes: Willier Zero 7; Merlin Extralight; Calfee Dragonfly tandem, Calfee Adventure tandem; Cervelo P2; Motebecane Ti Fly 29er; Motebecanne Phantom Cross; Schwinn Paramount Track bike
Mentioned: 17 Post(s)
Tagged: 0 Thread(s)
Quoted: 1447 Post(s)
Liked 727 Times
in
372 Posts
Wouldn't that be a huge hole in the Ibike? I got the impression that Ibike did reasonably ok for extended efforts, as long as it was calibrated correctly.
If it can't deal with the effect of a crosswind, doesn't that make it pretty much worthless?
If it can't deal with the effect of a crosswind, doesn't that make it pretty much worthless?
__________________
You could fall off a cliff and die.
You could get lost and die.
You could hit a tree and die.
OR YOU COULD STAY HOME AND FALL OFF THE COUCH AND DIE.
You could fall off a cliff and die.
You could get lost and die.
You could hit a tree and die.
OR YOU COULD STAY HOME AND FALL OFF THE COUCH AND DIE.
05-06-14, 09:37 AM
#39
Perceptual Dullard
Join Date: Sep 2009
Posts: 2,421
Mentioned: 36 Post(s)
Tagged: 0 Thread(s)
Quoted: 919 Post(s)
Liked 1,156 Times
in
494 Posts
I think the real competition for something like the iBike isn't the SRM but rather a Garmin head unit and Strava, and Strava is winning.
05-06-14, 09:39 AM
#40
pan y agua
Join Date: Aug 2005
Location: Jacksonville
Posts: 31,304
Bikes: Willier Zero 7; Merlin Extralight; Calfee Dragonfly tandem, Calfee Adventure tandem; Cervelo P2; Motebecane Ti Fly 29er; Motebecanne Phantom Cross; Schwinn Paramount Track bike
Mentioned: 17 Post(s)
Tagged: 0 Thread(s)
Quoted: 1447 Post(s)
Liked 727 Times
in
372 Posts
True. But something as simple as pacing intervals, or pacing a TT, would seem to be a problem.
__________________
You could fall off a cliff and die.
You could get lost and die.
You could hit a tree and die.
OR YOU COULD STAY HOME AND FALL OFF THE COUCH AND DIE.
You could fall off a cliff and die.
You could get lost and die.
You could hit a tree and die.
OR YOU COULD STAY HOME AND FALL OFF THE COUCH AND DIE.
05-06-14, 10:09 AM
#41
Perceptual Dullard
Join Date: Sep 2009
Posts: 2,421
Mentioned: 36 Post(s)
Tagged: 0 Thread(s)
Quoted: 919 Post(s)
Liked 1,156 Times
in
494 Posts
[Edit:] That said, it's hard to beat the dollar value of a used PowerTap. A friend recently bought a used (wired) PT for $275. I helped him do a static torque check so we know it's not only consistent but also accurate.
Last edited by RChung; 05-06-14 at 10:23 AM.
