On 04/03/10 10:20, James Morris wrote: > On Thu, March 4, 2010 09:48, Jonathan Gazeley wrote: > > >> 1. A sensor that can measure my cadence. A simple magnet switch that >> triggers once a revolution won't be enough to measure the cadence with >> sufficient resolution, since my cadence is usually between 50 and 80 >> rpm. I would probably need to mount multiple magnets spaced equally >> around the chainwheel and have a single sensor on the frame. Then I have >> to get it to supply this information to my control program. >> > Cycle computers which measure cadence work with a single magnet on the > crank and can measure cadence in that range and above. I think the fastest > RPM I ever got was (only a vague memory) around 120 (maybe?) when I was > being silly trying to see how fast I could pedal. > Yes - I have a cycle computer that can measure cadence. However, I typically pedal between 60 and 90 rpm which means my reading would only be available for sampling every 0.7 - 1.0s. It would work, but in the space of one second my cadence can vary a lot if I'm accelerating so the sound of the rising revs would be jumpy. Also, if I suddenly stopped pedalling, it might take up to a second for the sampler to register and kill the engine noise. I don't think it would be a very satisfactory experience, which is why I was thinking of mounting 10 or so magnets around the chainwheel, to be able to sample the cadence every 0.1s. _______________________________________________ Linux-audio-user mailing list Linux-audio-user@xxxxxxxxxxxxxxxxxxxx http://lists.linuxaudio.org/listinfo/linux-audio-user
