# Motor too weak with rubber band

we have a claw that picks up goals. We use a torque motor with rubber bands to get the claw to be tight. The claw cannot open with 2 rubber bands connected. any ideas?

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Use a gear ratio in order to increase the torque on the claw.

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If I understand the question right the motor is unable to counter the force of the rubber bands. In this case, why do you need them? A torque motor and a decent clamp should be able to hold the goal just fine. If it canâ€™ t then check the quality of your clamp or add a torque ratio.

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Torque is equal to force x radius x sinA; if you use the same motor at the same velocity (F=ma) the force exerted will be the same. If A (the angle) is the same, then you could take the rubber bands off and increase the radius of your clamp to increase torque and exert a little more force on the goal.

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The motor was able to go up with 5 rubber bands, before we added a high strength axle to increase the force of the claw. We have tried different amounts of rubber bands, but after a few tries the motor is unable to go up completely. My team has been thinking about the possibility of Motor problems.

See how hot the motor is after running. You may be heating up the motor to much and the motors will shut down after to much internal heat.

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We have a simple 3;1 ratio on the clamp. Even with this small of a torque ratio, no rubber bands are needed. We found that rubber bands simply overheats the motor because of the extra stress on it.

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Thanks, the information about motors overheating will be extremely beneficial to us, because we have had problems with the motor overheating.

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If you have a motor overheat, let it rest for about 15 secondsâ€“the motors are equipped with encoders that are meant to automatically lock them when they get too hot, and that resets after about 10-15 sec

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