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Unread 25-02-2009, 12:11
Ian Curtis Ian Curtis is offline
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Re: Implementing Traction Control for an advantage in the 2009 game

Quote:
Originally Posted by FRC4ME View Post
I'm wondering why everyone seems to be focused on measuring current. As far as I know, the equation we need (which calculates the amount of torque you are applying to the wheel, which cannot exceed the force of friction pushing back or you will slip) involves only voltage and angular velocity, not current.

http://www.gizmology.net/motors.htm

Could someone who is using current sensing in their traction control clue me in on how you are doing that?
Current is a function of wheel velocity. When the wheel begins to slip, the motor will spin faster and draw less current. As long the as change in current draw was sharp enough, I'd imagine it could potentially be simpler than measuring your velocity relative to the floor.
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