Thread: Manual Velocity PID, anyone successful?
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Unread 18-01-2006, 22:30
KenWittlief KenWittlief is offline
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Re: Manual Velocity PID, anyone successful?
as an engineer I have to say, a closed loop feedback control system is way more accurate and precise than any human on joystick could ever be.

Humans have eye to hand coordination at best around 1/10th of a second (100mS). The loop in the RC runs about ten times faster than that.

If a PID control robot drives worse than open loop, then something is not right with the control system: slop/backlash in the drive train, faulty sensors, PID gains not set for optimum response.

seriously, try to out calculate your calculator.

The one version of PID control I have seen used very successfully is a solid state yaw rate sensor (gyro chip) used to sense robot turn rate, and using a one joystick control setup. Then its very easy to use the turn rate from the gyro chip to close the loop on steering. This is exceptional when going up ramps and stuff, if your bot trys to turn sideways on the way up, and your driver is pushing the joystick straight, the PID loop will keep it going straight no matter what!