Last year I bought a RobotShop Robot Rover for Arduino (Tank Kit) and recently started building the robot. I’m having a problem with the motors (Solarbotics GM9s) that come with the kit failing after a short while. First it was one which died and was then replaced. Now back to 2 working motors, they both have failed as well.
I opened one of the motors and there is no physical damage that I can see like that which a short circuit might produce. I’ve put the circuit together twice. Any ideas about how I’m killing these motors?
Thank you both for your advice. I did as you suggested and tried connecting the motors to a battery. One motor seems to be entirely dead, but the other two worked. I decided to wire up the motor control circuit again on another breadboard and at first it didn’t work. After fiddling with the wiring, they are now working. I’m just beginning to use breadboards and am learning that I have to be more careful when wiring the things.
Also, your controlling circuit looks appropriate, but the direct battery test is a very good idea.
A possible cause for your problem could be worn-out motor brushes. If you run the motors for extended periods of time, the brushed will eventually wear-out and they will stop working.
Can you try running the motors direct using a battery or battery pack t osee what happens? If there is no physical dammage to the gears or coils (harder to determine), and the motor shaft spins freely, then the source of the issue is likely not the motors.
