Encoder error occur after 4 minute, a no load Actuator Module Testing

hello, every one.

I met some weird condition. I did some Actuator Module Testing today, a no load test. just Antigravity 4004 motor and Optical Encoder Mounting on the Shells, no Timing Belts and Center Pulley.

I gave the motor 0.3A current, it run at about 50 rpm, an encoder error will occur after running about 4~5 minute every time, even though i cool the DRV8305 chip.

encoder error is 1 or 6. the shell was fixed , no move.

does anyone meet the same problem or have any idea?
Thank you very much


I personally did not use the motors for continuous rotation, maybe these errors happen at specific position?
If you say that the motor is about 4-5 min at 50rpm this mean you reached a position of about 250 turns. You could log the position to have a precise idea. We should then check in the code how the encoder error is handled and if it is sensitive to position rollover.
Hope this helps,
Best, T.

hi, thomas, thanks for your reply.

i made a mistake yesterday, the velocity was 360~400, about 60 turns per second, not 50 rpm.

today i do the continuous rotation testing again, still no load test. the first time, encoder error 1 occur at 4 minute and 30 second, the third time, error occur at 3minute and 11 second. oh, the second time, it run over 6 minutes and no error.

BTW, during the test, I use a fan to cool the 28069 and 8305 chip. the shell was fixed , no move.

I will do the same test using another motor 、optical encoder and udriver board, and record the results. if i find something, i will response to you.

hi, thomas

sorry, i ignored something.

the two M3 set screws of the rotor might be little loose. I put a bit of threadlocker on the two M3 set screws, and reassemble the M3 set screws and motor shaft. the problem gone.