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Robotic gripper circuiot problems

  1. Dec 29, 2009 #1
    Robotic gripper

    I need some ideas on how to solve these problems;

    I have 5 identical motors running independantly in the gripper. Each one of them has a slightly different internal resistance and therefore pulls a different current.

    My main problems are either the motor losing power or overheating, this is due to the motors not pulling an equal current. I think the problem might also stem from the very small H bridges that I am using to drive each of the motors.

    What I am interested in knowing is if there are any novel solutions to minimise and control the mechanical friction, and also to minimise any voltage drops. Ideally I am looking for a situation where the force of each motor in the gripper is exactly proortional to the current. Also that the force and the current could be read accurately from a powerprofile for each of the motors.

    Do you think I would see an improvement if I used a thermagel heat dissipation strip attached to the H bridges?

    Any ideas would be appreciated.
  2. jcsd
  3. Dec 29, 2009 #2
    You didn't state the Vcc voltage, the H-bridges, and the motor current you are using. Most H-bridges are relatively inefficient below ~6 volts; 12 volts is better. Are you using PWM (pulse width modulation) to control motor current? The automotive industry has made 12 volts a standard for H-bridge efficiency and performance design. Are any of your H-bridges too hot to touch? If yes then heatsink it to metal with thermally conductive compound.
    Bob S
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