| Joseph Hebert 03/10/12 18:46 Read: 208 times Okemah, Ok United States |
#186572 - Point made Responding to: Per Westermark's previous message |
You made your point in the first paragraph. Torque ∙ rpm (in Hz) = N∙m/s = kg∙m/s^2 ∙ m/s = W. The point to remember is that it's the rpm of the pedal that must be measured, rendering the gear ratios irrelevant. This also renders losses to drag, and changes in potential energy, irrelevant. Going uphill you produce more watts, downhill less. Ride in a headwind, more wattage; tailwind or drafting less. It's a direct measure of the watts the rider is generating. Excellent point! This is an elegant solution.
Joe |
| Topic | Author | Date |
| bikey design challenge | Jez Smith | 03/09/12 12:14 |
| Only 400W? | Per Westermark | 03/09/12 12:23 |
| Its a bit different on the road | Jez Smith | 03/09/12 12:34 |
| Brilliant idea in the bath | Jez Smith | 03/09/12 13:35 |
| Might work | Per Westermark | 03/09/12 13:51 |
| well... | Jez Smith | 03/09/12 14:33 |
| So you are yourself saying 400W is a bit low max scale | Per Westermark | 03/09/12 14:43 |
| O.K then 500 watts | Jez Smith | 03/10/12 00:56 |
| Battery | Per Westermark | 03/10/12 05:11 |
| Fun with strain gauges | Oliver Sedlacek | 03/12/12 05:57 |
| You sure? | Per Westermark | 03/09/12 13:48 |
| nice ride | Andy Peters | 03/09/12 14:31 |
| fanks | Jez Smith | 03/10/12 00:54 |
| Sigma Rox 9.1... | Kai Klaas | 03/10/12 09:59 |
| Sigma fake | Per Westermark | 03/10/12 11:07 |
| What do you expect for that price? | Kai Klaas | 03/10/12 12:09 |
| Head or tail wind? Or riding in a group or alone? | Per Westermark | 03/10/12 12:38 |
| Way overcomplicating this | Joseph Hebert | 03/10/12 14:02 |
| Sensors | Steve M. Taylor | 03/10/12 14:22 |
| how indeed | Andy Peters | 03/11/12 12:37 |
| Wrong - you are totally missing the drag factor | Per Westermark | 03/10/12 14:22 |
| Not at all. | Joseph Hebert | 03/10/12 16:03 |
| Real manufacturers haven't found your idea simple... | Per Westermark | 03/10/12 17:09 |
| Point made | Joseph Hebert | 03/10/12 18:46 |
| Some of your points are just wrong | Justin Fontes | 03/10/12 19:04 |
| Sounds like you expect an infinite acceleration | Per Westermark | 03/11/12 06:49 |
| Repeat post Ignore | Justin Fontes | 03/11/12 11:39 |
| I try for a constant power | Justin Fontes | 03/11/12 11:52 |
| Crank rpm - not back wheel rpm | Per Westermark | 03/12/12 00:31 |
| I got the two confused | Justin Fontes | 03/12/12 10:37 |
| Bandwidth + return channel | Per Westermark | 03/12/12 12:07 |
| Oh dear, so many variable constants | Oliver Sedlacek | 03/12/12 06:48 |
| rocket science | Maarten Brock | 03/11/12 03:58 |
| So don't ignore them | Joseph Hebert | 03/11/12 07:39 |
| Of course, it is... | Kai Klaas | 03/11/12 08:18 |
| wireless | Joseph Hebert | 03/11/12 08:36 |
| Costs... | Kai Klaas | 03/11/12 12:59 |
| cost | Joseph Hebert | 03/11/12 13:39 |
| Another problem | Joseph Hebert | 03/12/12 21:14 |
| This was addressed earlier | Justin Fontes | 03/12/12 22:02 |
| Multiple strain gauges | Per Westermark | 03/13/12 00:53 |
| Competitive bicycling | Justin Fontes | 03/13/12 10:24 |
| Pulse | Per Westermark | 03/13/12 10:55 |
| If I had the power meter | Justin Fontes | 03/13/12 11:14 |
| Normalizing with heart beats cancels some errors | Per Westermark | 03/13/12 12:39 |
| Just to get some data to look at | Jez Smith | 03/15/12 03:37 |
| Jez ? | Steve M. Taylor | 04/14/12 04:35 |
| Oh Noes!!!!!! | Jez Smith | 04/14/12 10:58 |
| The plan is | Jez Smith | 04/15/12 01:55 |
| Brum doesn't HAVE mountains | Steve M. Taylor | 04/15/12 14:51 |
| Ah yes but no but | Jez Smith | 04/15/12 23:23 |
| Actualy... | Jez Smith | 04/15/12 23:35 |
| If I had a power meter... | Oliver Sedlacek | 04/16/12 04:20 |
| Ive been testing things | Jez Smith | 04/16/12 04:41 |
| Well, no | Steve M. Taylor | 04/16/12 07:41 |
| all very well thank you Steve | Jez Smith | 04/16/12 08:45 |
| Getting nasty | Steve M. Taylor | 04/17/12 10:54 |
nasty ? | Jez Smith | 04/20/12 12:09 |
| More time than money if access to machinery | Per Westermark | 03/12/12 00:57 |
| Strain gauge elastic fixtures | Oliver Sedlacek | 03/12/12 06:55 |
| Sure | Per Westermark | 03/11/12 09:42 |