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Unread 16-02-2009, 03:47
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Re: 2809 - Traction Control Demo

My team's traction control design works in 2 ways:

We have 4 encoders total, 2 on free-rolling wheels and the other 2 on drive.
The (open-loop) system for "slip prevention" maximizes the wheel torque (motor power) based on the robot's actual velocity (from free wheels) according to an equation that we found empirically. This ensures our applied power will never slip no matter that external forces hit us (and extreme joystick inputs applied).

Our 2nd (closed-loop) system for "slip recovery" detects slip (that is, rotation rates of powered wheels vs free wheels) and proportionally steps down the power accordingly until the slip is gone.

End result? Today at our scrimmage we never slipped with traction control.....but we were pretty slow and underpowered. Any quicker and we start to slip. For better or for worse I suppose.