Robotic gripper circuiot problems

[mh5594]

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.

 

[Bob S]

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