encoder motor control

[pauldemonkey]

We are trying to use the encoders provided in the kit to stop our kicker so it will stay within the bumper perimeter. We have the basic encoder example, we are just unsure how to stop the motor so the kicker is in regulation.

[Doc Wu]

Originally Posted by pauldemonkey

We are trying to use the encoders provided in the kit to stop our kicker so it will stay within the bumper perimeter. We have the basic encoder example, we are just unsure how to stop the motor so the kicker is in regulation.

It helps first, to know the limitations of the devices you are using.

An encoder, or for that matter, a limit switch, does not stop a motor. It tells the controller what it knows about the position of your kicker, but stopping it, especially when moving rapidly, is a mechanical issue.

Motors and moving mechanics tend to keep moving, even when told to stop, because of inertia.

To stop your motor in such a situation, you'd have to start stopping it well in advance to account for that overshoot. Even countering the motion by commanding it to reverse would take time. By the time you got that to work, there'd be no energy left to transfer to the ball.

What you need is a hard stop, a mechanical item, that limits the travel of your kicker. Then an encoder or switch can be used to tell the controller that it has reached the stop.