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Unread 11-02-2016, 15:47
Knufire Knufire is offline
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Re: CIM Motor Reversing

Quote:
Originally Posted by parbas View Post
We're having an issue with a CIM motor operating in reverse. In our code, we have a CIM motor set to go forward for half a second and then in reverse for half a second (both at full speed) at the press of a button. The issue is that the motor does not go back to it's starting position like we thought it would. It goes further back than it was when it started, which is causing an arm to move further and further back with each button press.

Any ideas?

Thanks!
There are many variables you are not controlling. Things like battery voltage, arm. angle (the load on the motor required to move the arm when it is horizontal is much more than when the arm is vertical), the motor may be biased in one direction, etc. Simply applying a percentage of battery voltage for a specified amount of time isn't going to let you preciely control the position of the arm.

You will need to put a sensor on the arm joint to measure the angle of the arm, and use that measured angle in code with a control loop to control the position of the arm.
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