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Unread 01-25-2009, 09:57 PM
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Re: PID traction Control

Quote:
Originally Posted by dpeterson3 View Post
One of our mentors mentioned doing PID loops for traction control. I read the theory behind it, and understand most of it. I am just not sure where to get SetPoint values and where to take sensor readings, especially considering they say you should programatically get the set point value. I want to code in C++ (eveyone else wants to use LabView), so I need a little help with this. Do I use an accelerometer or encoders, or both and How do I get my setpoint ?
You will need to be able to read both the wheel speed and the actual speed of the robot.

I would do this by putting an encoder on the wheel (to tell wheel speed) and a follower wheel with encoder (Watch to make sure it does not provide too much traction).

From there you can find the delta speed (differental between the 2 speeds ... usually called error) and then adjust the power to the motors until both are spinning at the same rate (or whithin x%)
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