This is a modular prosthetic foot, a fully 3D printable prosthetic foot, using modular architecture principles.The design is open source and you can download, test it and improve it.
DISCLAIMER: Be careful and DO NOT use it without help of a prosthetit, although in the video the amputee performed a gait test using the prosthetic foot, it is still a prototype and current 3D printing materials will probably fail after a couple of uses (because of the fatigue stress), I used ABS but you could test it with PC, nylon, nylon-carbon fiber or other.
To assembly the prosthetic foot, you need:
3D printed parts:
Non-3D printed components:
1 or 2 spring for the heel component
4 x M4 bolts (40mm length) and nuts for assembly the pyramid adapter and the keel
2 x M5 bolts (20mm length) and nuts for assembly the bottom of the springs to the sole
2 x M4 bolts (20mm length) and nuts for assembly top of the springs to the keel
1 x M6 bolt (20mm length) and nut for assembly the sole with keel in the front
4 x washers for keeping secure the spring
Gait test video:
As you can see in the picture, one can adjust the height of the foot by scaling up in Z the size of the Top-adapters. Adjust the length of the foot (1cm = 1 foot size) by adjusting the position of the sole; and one can modify the stiffness of the springs or its amount according to the user preference.