Problem with controlling DC Servo Motor

[Minho123]

I'm working on a project on Servo motor control with Myrio. I’m reading pulse from encoder by LabView, then calculating the output and export Analog Output to the Driver of the motor, in addition to controlling the direction of the motor is required to export a DI signal to the driver. I use two sets of PIDs, the inner loop controls speed, the outer loop controls position.

The setpoint positioning is a sine signal. The problem I have is that our algorithm does not cling orbital, although it has a sine shape but is late and the amplitude is much different from the setpoint (illustrated below). I have attached the VI in link below.

Please help. Thank you very much

 

[GerdW · Accepted solution]

Hi Minho,

from that image it seems you forgot to set resonable PID gains!?

How did you determine PID gains?

[Minho123]

Thanks for your help
I just use one loop for position control, and adjust PID gains. And I have result: