Using ACOPOSmicro stepper module 80SD100XD.C033-01 with two stepper motor 80MPF5.500D113-01.
The following issue can be observed when:
1. The ‘Position andCurrent Controller’ is used.
2. Position feedback is taken from the encoder.
When executing motion commands such as ‘MoveVelocity’, ‘MoveAbsolute’, or ‘Jog Positive/Negative’, the axis produce a high jerk at the start of motion and then stops at a fixed position with generating noise and vibration.
When position command is given, it is also that it moves with high speed automatically when the command is completed!
When tested with only Current Controller, above commands was working ok.
The same behaviour can also be verified in mapp Cockpit.
Could you please suggest something to rectify this issue.
What you are observing is an instable Position Loop due to high Proportional Gain.
A Gain of 20 is rated as high in context of this long cycletime of the Loop.
If you start moving the Controller reacts very strong and this results in a oszilation of the velocity. With higher Velocity your motor cant follow the Steps and goes into Stall. Due to your out of Range Position error limit of 1000 Messurement Units you do not get a LagError from the Position Loop. But your Set Value goes to the end of the movement, reducing the Velocity. I assume that then the Motor starts to follow the Velocity again and reduces the LagError until he reaches the Endpoint.
Validate the Prediction and Total delay time in consideration of the Fieldbus Timings and Arrangement. See information in my Guide or in AS-Help.
For this Step it is usefull to set Proportional Gain to 0.
Set the Proportional Gain to a Value of ~1 and start optimising Loop Control from there
Reduce the Position Error to a usefull Value
Use a Trace in MappCockpit to see Position, Velocity, LagError, MotorSteps
