Gripper Binds Up

Hope someone can help here. I recently bought the Clawbot kit. I seem to be having an issue with the gripper opening and closing after doing it a few times then it gets stuck. Any one ever have a similar issue?:confused:
My setup is controlled via a Spectrum 2.4G radio, and have the gripper being controlled by the throttle stick via the controller"29". I was thinking about maybe trying another servo motor. I did notice that when I apply power to the gripper motor with out the controller, it does seem to work, but Id rather try to use the motor controller. Since t he gripper came pre-assembled, is it easy to take apart?

Any help, ideas, comments would really help. I want to build a bigger bot but want to get t he gripper fixed first before I go buy another one.

Hello and welcome to the forums,

It sounds like you are tripping the claw’s internal breaker. When you apply load to a DC motor it generates heat - the more load the more heat. The worst case for this is when the motor is stalled (throttle is applied to the motor, but it does not have enough torque to rotate). A stalled motor will overheat and die. VEX 393 motors include a breaker that will trip to protect the motor from overheating. If you trip the breaker, it will reset a few seconds after throttle is no longer applied. The breaker trips when it becomes hot, so if it trips once it will trip very easily until it has time to sit and cool. The motor should return to full performance after the breaker has had time to cool (15-20mins).

When using the claw, try not to apply throttle to hold the claw open or closed for extended periods- if you must apply throttle, apply as little as possible.

Let me know if you have any more questions,


Hello, and thank you for the info.
The big issue I still have with the gripper is that it would stop opening and closing only after a few times, right after I’d power up the robot, and I’m not even grabbing anything with it yet.
I purchased another Controller 29 module thinking that was the issue. But I still have the same problem.
What does seem to work fine, is that if I apply the battery voltage directly to the gripper motor (no controller), it opens and closes just fine. I’m thinking of using an r/c relay to operate the gripper instead of the using the controller.
One last thing I did notice, is that there seems to be washer/spacer missing from the shaft of the motor just below the gear.
Any other ideas here? Id like to build the robot up more but not until I get this gripper issue settled.

If this is the case, you should be able to connect the claw motor directly into motor port# 1 or 10. Such ports do not require a motor controller.

If this takes care of the problem you will need to write a program using ROBOTC or easyC to re-configure motor port# 1/10 as a “Claw motor” and not a drive motor.