Motor Position Control with no torques about fast_and_efficient

[yxyang]

Hi,

Regardless of the motor control mode I defined in the python code, the code uses the same "hybrid" low-level control mode to interface with the Unitree SDKs. That is, it always sends in a 5-dim vector for each moro, including Kp, Kd, p_ds, v_des and extra torque. Then the a1_robot.py builds an extra layer on top that enables position or torque control.

Regarding the non-zero position error from position control, my understanding is that this is a classic issue with PD control, which introduces a steady state error unless an integral term is included. I'm not very familiar with the exact case you are describing though.

Best,
Yuxiang

[Charlescai123]

Hi Yuxiang,

I've made a test and think my problem is because the Kp and Kd gain are not set properly which prevents the robot from standing up due to the gravity. Anyhow thank you for the reply! Close it now.

Best,
Yihao