Cant read the servo angle for SERVO_HAND

uArm Swift (Pro) Troubleshooting
1

Firmware Version: 1.7.3, pyuarm 1.3.29,

read_servo_angle() always returns 0.0 for the hand servo:
>>> arm.read_servo_angle()
Serial Write: f0aa100001f7
Serial Read: f0aa00530019f7
Serial Write: f0aa100101f7
Serial Read: f0aa01640053f7
Serial Write: f0aa100201f7
Serial Read: f0aa023c003af7
Serial Write: f0aa100301f7
Serial Read: f0aa03000000f7
[83.25, 100.83, 60.58, 0.0]

It works perfectly in uClient.

2

I’m retrieving the data from pyuarm with python, I have the same.

By the way I cant control the hand servo with move_to. it might be linked

3

I noticed I can read and write the angle if I use the absolute parameter

#Must use False for offset, not calibrated?`
arm.read_servo_angle(pyuarm.SERVO_HAND, False)
arm.write_servo_angle(pyuarm.SERVO_HAND, 90, False)
4

Hi @GummansGubbe, You could use uarm-calibrate to calibrate again, will fix the issue. because manual hand servo offset return null, cause the problem. You could refer this guide uarm-calibrate guide

5

Yes indeed, that solved it. Thanks!