We have two different robots, whose clawbot motors seem as though they are working fine, but at times will not open the claw as directed in the program. Yet, if we listen, you can hear the motors still trying to work even though they are not opening the jaws of the claw. Any ideas? I am assuming that if the built-in circuit breaker had tripped, one would not hear the motor still trying to work.
Make sure that the shaft is not coming out of the motor and disengaging the system from the motor. You can also pull the shaft out of the motor a little ways and look to see if the hub in the motor turning. If it isn’t then theres probably something wrong with the internal gears.