Grey cylinder of pink piston controls the gripper.
Pink jaw is fixed to the piston. Yellow jaws are fixed to gear sectors that receive motion via blue pinions.
When the orange cylindrical work is gripped, its axis is in vertical symmetrical plane of the gripper.
STEP files of this video:
http://www.mediafire.com/download/bf4wwelb4jcfl53/GearRackGrip1STEP.zip
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