Help with Closed Loop Control Tuning

Support
1

I’m trying to drive a pair of 190KV BLDC motors with integrated hall sensors. I’ve gotten past motor and encoder calibration, but since I don’t really understand closed-loop motor control, I don’t really grok the tuning process.

With the values I currently have, when I set a target velocity, the motor (I can only run one at a time before hitting some current limit) takes ~30 seconds to start spinning, and then gradually pics up speed. Then when I try to set the velocity back to 0, nothing happens: the only way to stop it is to set its state from CLOSED_LOOP_CONTROL to IDLE.

Here’s my setup code:

def set_config(odrv):
  # Settings to protect battery
  odrv.config.dc_bus_overvoltage_trip_level = 24.7
  odrv.config.dc_bus_undervoltage_trip_level = 19.2
  odrv.config.brake_resistance =  0.5
  
  for axis in [odrv.axis1, odrv.axis0]:
    axis.motor.config.current_lim = 45

    axis.motor.config.pole_pairs = 7
    axis.motor.config.resistance_calib_max_voltage = 4
    axis.motor.config.requested_current_range = 90 #Requires config save and reboot
    axis.motor.config.current_control_bandwidth = 100
    
    axis.encoder.config.mode = ENCODER_MODE_HALL
    axis.encoder.config.cpr = 45
    axis.encoder.config.bandwidth = 100
    
    # I think the issue is in these 3 lines?
    axis.controller.config.pos_gain = 1
    axis.controller.config.vel_gain = 0.02
    axis.controller.config.vel_integrator_gain = .1

    axis.controller.config.vel_limit = 1000
    axis.controller.config.control_mode = CTRL_MODE_VELOCITY_CONTROL

Can anyone give pointers on the tuning process? I looked through https://docs.odriverobotics.com/control.html, but still don’t understand + the issues listed there aren’t the same as what I’m see.

2

For clarification, there’s no error code or anything.

3

Howdy,

The ODrive hoverboard motor code is pretty shit ngl.
This code actually works Motor Current Unstable error
make sure if u are using rc to put the pwm shit in. Sensorless also works pretty well with the hoverboard motors, I can hook u up with mine if needed.

Have a great fucking day