I designed the Raptor to be a basic terminal prosthetic hand that could be 3-D printed. There are only 4 pieces that are printed and they can be made at a home printer.
I designed the Raptor hand for a design competition on GrabCAD. As of this post the competition is still up.
If you would like to print the Raptor yourself here are all the files that you need
If you would like me to design a custom application prosthetic for you feel free to contact me.
Here was a demo of the prototype. I used shockcord and paracord as the cables which is way to bulky. In future I will likely use small steel cable a maybe just rubber bands.