I have been keeping busy with numerous senior design projects. This was a not-adapted design for a claw in my mechatronics project. We ended up going with something else, two legs of the claw with a cam in the middle. From the original design (a worm gear and two center pieces to move the legs in and out) we tried to improve the speed, which was one of the major goals of the project. The direct drive screw moving the legs of the claw in and out was effective but extremely slow, even with a bigger screw.
My design represents an intermediate design where we considered having two sides and only one that would rotate to clinch the pieces. However, we were able to incorporate the cam into the existing built parts and went from an open/close time of 9 seconds to less than 1 second.