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 Robotics / RCX / 1303
  Maximum sample rate (turn rate) for rotation sensor
 
Does anyone know the correct maximum sampling rate for the Lego rotation sensor? This morning I noticed that Dave Baum gives a value of 1250 RPM in his "Definitive Guide" (page 29), but looking at (URL) see a value of 500 RPM. Which is correct? (...) (23 years ago, 20-Jul-01, to lugnet.robotics.rcx)
 
  Re: Maximum sample rate (turn rate) for rotation sensor
 
The hardware can actually do (in my testing) up to ~3000 rpm with good accuracy. The problem is with the standard software, which cannot do more than some low number (which may or may not be 500, I don't recall) because of how it samples the HW. (...) (23 years ago, 20-Jul-01, to lugnet.robotics.rcx)
 
  Re: Maximum sample rate (turn rate) for rotation sensor
 
When using the standard firmware, sensors are sampled every 3 ms. The rotation sensor uses a quadrature encoder with a 1:4 gearing between the axle and the encoder, so there are 16 "ticks" per revolution of the axle. The decoding routine in the (...) (23 years ago, 21-Jul-01, to lugnet.robotics.rcx)
 
  Re: Maximum sample rate (turn rate) for rotation sensor
 
Dave and Luis, Thank you both for the information. I'm big admirer of the work you've done for the RCX community. (...) I see. (60/0.003)/16 = 1250 And if you were worried about the Sampling Theorem you would divide that in half just to be sure.. (...) (23 years ago, 21-Jul-01, to lugnet.robotics.rcx)

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