Speed control with CUI AMT encoder

1

In the manual, position control is described with a CUI AMT encoder but speed control with a Hall encoder.
Is there anything against using a CUI for speed control? If not, how do I configure it?

I have a D5065-270KV motor from ODrive, and a CUI AMT encoder set to 500ppr (= 2000cpr).
I have calibrated successfully and position control works fine.

However in speed control, nothing happens, so when I do:
odrv0.axis0.controller.config.control_mode = CONTROL_MODE_VELOCITY_CONTROL
odrv0.axis0.controller.input_vel = 1
Odrive simply doesn’t react at all. (my max velocity is set to 2)

2

I received no answers, but maybe someone can tell me where on Github the C++ code of velocity control firmware is stored. It would help me to understand why the odrive doesn’t react to a velocity command, while not coming back with an error.

3

Higher resolution is better for velocity control. CUI encoder is going to be better than the halls for this.

Maybe try increasing your vel_gain and make the vel_integrator_gain non-zero.

4

I now tried sensorless control according to the manual:

odrv0.axis0.config.sensorless_ramp.vel = 160 
odrv0.axis0.config.sensorless_ramp.accel = 16 

odrv0.axis0.controller.config.vel_gain = 0.01
odrv0.axis0.controller.config.vel_integrator_gain = 0.05
odrv0.axis0.controller.config.control_mode = CONTROL_MODE_VELOCITY_CONTROL
odrv0.axis0.controller.config.vel_limit = 1.2 * odrv0.axis0.config.sensorless_ramp.vel / (2 * 3.1416 * odrv0.axis0.motor.config.pole_pairs)
odrv0.axis0.motor.config.current_lim = 2 * odrv0.axis0.config.sensorless_ramp.current
odrv0.axis0.sensorless_estimator.config.pm_flux_linkage = 5.51328895422 / (odrv0.axis0.motor.config.pole_pairs * MOTOR_KV)
odrv0.axis0.config.enable_sensorless_mode = True
odrv0.axis0.config.enable_sensorless_mode = True

odrv0.axis0.requested_state = AXIS_STATE_MOTOR_CALIBRATION

then:
odrv0.axis0.requested_state = AXIS_STATE_CLOSED_LOOP_CONTROL

the motor now rotates fine but oDrive still ignores the odrv0.axis0.controller.input_vel = … command, so I can’t change the speed while the motor is spinning.
Is that normal?