To LUGNET HomepageTo LUGNET News HomepageTo LUGNET Guide Homepage
 Help on Searching
 
Post new message to lugnet.robotics.rcx.legosOpen lugnet.robotics.rcx.legos in your NNTP NewsreaderTo LUGNET News Traffic PageSign In (Members)
 Robotics / RCX / legOS / 3298
    Varying the output voltage? —Aaron Goodman
   I was wondering if it was possible to control the speed/torque of the motor by varying the output voltage in brickOS. It seems that the speed parameter on the motors only changes the rate at which they pulse on and off. I am looking for something (...) (21 years ago, 14-Jun-03, to lugnet.robotics.rcx.legos)
   
        Re: Varying the output voltage? —Timothy Schroeder
   (...) The eight different power level pulsing is called "PWM", translation=Pulse width modulation. PWM is the way a digital chip cheats/mimics true analog without a D/A convertor. Since the only output of a digital chip is on or off, there is no (...) (21 years ago, 14-Jun-03, to lugnet.robotics.rcx.legos)
   
        Re: Varying the output voltage? —Juergen Stuber
   (...) Actually there are four, sort of, as for 0 there are float (contacts separated, infinite resistance) and brake (contacts shorted, zero resistance). The standard firmware switches rapidly between on and float (each cycle takes 8ms), which (...) (21 years ago, 14-Jun-03, to lugnet.robotics.rcx.legos)
   
        Re: Varying the output voltage? —Aaron Goodman
      This is what I noticed, comparing the two systems with BrickOS One thing that I noticed was at the lower voltages the needle on my multimeter wavered around a little and it tended to steady at the higher power levels All of the readings were taken (...) (21 years ago, 14-Jun-03, to lugnet.robotics.rcx.legos)
   
        Re: Varying the output voltage? —Timothy Schroeder
   (...) you're right, I forgot float. Thanks for clearing the rest up for me :-) Doesn't the motor itself have a "load" when it works with no actual load? "which reduces power but not speed" Timothy (21 years ago, 15-Jun-03, to lugnet.robotics.rcx.legos)
   
        Re: Varying the output voltage? —Juergen Stuber
   (...) The power motors that come with the RIS are very efficient, so the load is very light and speed changes very little. Then of course it depend on your robot, if you use caterpillar tracks you will generally have more load than with wheels. An (...) (21 years ago, 15-Jun-03, to lugnet.robotics.rcx.legos)
 

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