To LUGNET HomepageTo LUGNET News HomepageTo LUGNET Guide Homepage
 Help on Searching
 
Post new message to lugnet.robotics.rcxOpen lugnet.robotics.rcx in your NNTP NewsreaderTo LUGNET News Traffic PageSign In (Members)
 Robotics / RCX / 1303
    Maximum sample rate (turn rate) for rotation sensor —Gary Lucas
    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 —Luis Villa
     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 —Dave Baum
   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 —Gary Lucas
   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)
 

©2005 LUGNET. All rights reserved. - hosted by steinbruch.info GbR