The rear left hip motor of our Unitree A1 can’t apply any torque. The motor is much harder to move compared to the other hip motors when the robot is off. The robot is able to boot and stand up sometimes, but it can’t walk because the rear left hip motor only has some resistance and can’t move on its own.
In the system report, there does not seem to be anything wrong. The motor even reports its position correctly. But when we send commands to specifically only move the problematic motor, we can’t detect any reaction, like a different sound or a weak movement.
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Motor lose connect ([ ]/100ms):
FR 0 0 0 ; 1 0 3 ; Joint-> 0.1336 0.4971 -1.7023
FL 0 0 0 ; 1 0 3 ; Joint-> -0.1307 1.3370 -1.7998
RR 0 0 0 ; 1 0 3 ; Joint-> 0.2436 0.8991 -1.8069
RL 0 0 0 ; 1 1 3 ; Joint-> -0.6251 0.8675 -1.8062
IMU :: Roll = -0.8739, Pitch = 1.1370, Yaw = 10.6796
Foot Force :: [FR_] = -1.06, [FL_] = -1.70, [RR_] = -20.86, [RL_] = -5.18
GamePad CMD:: 0.00, 0.00, 0.00, 0.00
RobotVersion = 400
Firmware_version = 1000200525
HardwareVersion = 1000200420
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Motor lose connect ([ ]/100ms):
FR 0 0 0 ; 1 0 3 ; Joint-> 0.1336 0.4971 -1.7023
FL 0 0 0 ; 1 0 3 ; Joint-> -0.1307 1.3370 -1.7998
RR 0 0 0 ; 1 0 3 ; Joint-> 0.2437 0.8991 -1.8068
RL 0 0 0 ; 1 0 3 ; Joint-> -0.5187 0.8675 -1.8062
IMU :: Roll = -0.1846, Pitch = 2.1050, Yaw = 10.9749
Foot Force :: [FR_] = -3.56, [FL_] = -2.20, [RR_] = -22.36, [RL_] = -5.68
GamePad CMD:: 0.00, 0.00, 0.00, 0.00
RobotVersion = 400
Firmware_version = 1000200525
HardwareVersion = 1000200420
We are now wondering if the motor needs to be replaced or if this issue can be fixed in a different way. If there is any other info that we can provide or things we could try, feel free to let us know. We would be thankful for any advice!