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Nov 5

Calibration issue on servo 8 and 9

6 comments

Hello, i have an issue with calibration. I have new kit with v2 board, original servos. Batteries are ok, measured and fine but i did try external laboratory power supply as well but without luck.

 

First, i did basic calibration with "c" on serial console and set basic leg angle as on following picture:

Them i start to calibrate using command "c8 number" to do fine tuning. Servo 8 and 9 are acting weird, when i send "c8 0" several times ( mean i will send same command over and over ) servo move to random position:

This is happening only to servo 8 and 9. Servo 10 and 11 works fine mean command c10 0 will not move servo at all and c10 1 will move it little bit. Multiple same commands are working fine too.

 

Next weird is when i reset serial connection akka restart main board and send command "c" for basic calibration position all legs move to correct position.

 

Any suggestion before i will start some deep debug action ? :) Thanks

Ok problem solved with resoldering all critical looking points :)

7 days ago

Glad to hear the problem was solved. Do you think it's the soldering problem? At the points of servo plug pins?

7 days ago

I did all points to be sure. Nybble is now working but it have "neural tick" at some point, for example when i press "ch-" to sit then at some point - always at same, all or almost all servos shake for a tenth of second then return back to correct track. It happen even when i hold it in air so i guess it is not servro load ?

6 days ago

It’s not. It's a imperfection in the algorithm. When holding static postures the angle feedback is added. But during transition there's no feedback. So the jump will happen at the end of each posture transition.

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