Alternative to PID speed control

[mommazzboy]

Originally Posted by Ether

Make sure you scale the feedforward appropriately and then clamp the result after you add it to the PID output.

Can you expand on this some? We're setting the motor outputs in PWM, so the input to the VI needs to be between -1 and 1 inclusive, so we should make sure that the sum of the feedforward and the output of the PID never goes out of that range. Is that what you mean by "scale the feedforward appropriately"? If not, what do you mean? And what do you mean by "clamp the result"?