This is a parametric robotic claw that I have designed. The purpose is to allow the claw design to accommodate a variety of objects to lift. The example I have built has a reduction gear stage to increase the servo power and to widen the profile allowing the claw to grip cubic blocks of 100mm edges. The SCAD design allows selection of the number of gear stages, length of the arms, beam thickness, as well as a few other parameters. With this design you can generate any claw your robot could need.

Am example of the claw operating can be seen here: http://www.youtube.com/watch?v=ribNNGnRoTQ

and here: http://www.youtube.com/watch?v=Hxc98augCaA

1. Modify the object you want to size against
2. Change settings to customise your claw until correctly sized
3. Customise the print_plate module to build for printing
4. Print and assemble the claw

Notes:

1. I still need to modify the single stage servo positioning on the plate and driven gear
2. The servo mount is for a med servo I had for a sparkfun claw, this may need to be modified for your design
3. the gears can be fixed together with 3mm PLA filiment
4. you may need to adjust Gear_Play depending on the quality of your printer