pic: the inventor file

[MrForbes]

It really only needs a motor on one side of the gripper...and you could make the other side spring loaded so it fits in the starting configuration size limit, but also will bend over several inches to allow the ball to be centered (as you run the motor on the other gripper)

[sea_master]

i don't understand what u are saying .
the arms need to rotate back and forward and also open and close on the ball.
how can it be done with only 1 motor?

[MrForbes]

Oh, I didn't realize the need to rotate, so what I said was wrong...sorry!

If the arms only need to rotate over the lift when the lift is in the full up position, then you could connect both sides together with a shaft, and then you would only need one motor. I can not tell enough about your design to know if this would actually work, though. Does the center part slide all the way to the top of the channel?

[sea_master]

now i see, we thought about it but it wont work with 1 shaft.
what u suggested might work i will check it out!
thanks alot!