The thigh frame of the U-Build Bionic Knee is the structure that connects directly to the prosthetic socket or bypass. It also connects to the thigh frame via a rotational joint to form the powered knee joint. Motion of the thigh frame relative to the shank frame is controlled using an electric motor and a transmission mechanism. Thus, the thigh frame includes some transmission elements and some electronic components. This section outlines the process of 3D printing and assembling the power knee.
Step 0: Review design files and print the thigh frame
Please review the design and print files of the thigh frame. The thigh frame can be printed with PLA material. We recommend printing with a 0.8 mm print nozzle and 0.4 mm layer height to decrease print time. The printer should be programmed to use 4 layer thick walls, ceilings, and floors and print at 50% or higher infill density. The parts should be printed horizontally such that each layer runs the length of the assembled knee (see example to right).
Step 1: Attach Flange to Thigh Frame
This step outlines the process of pressing and securing the flange adapters and four M6 square nuts to the thigh frame. The flange adapters interface and transmit power between the thigh frame and the transmission mechanism. They are secured to the thigh frame through a friction fit and six M4 button head screws. The four M6 square nuts are press fit into the thigh frame and are used to secure the pyramid adapter to the thigh frame. To complete this step, you will need one printed and cleaned thigh frame, one printed nut holder, six M4 by 60 mm button head screws, six M4 square nuts, six M4 washers, and four M6 square nuts. You may also need a 0.75" hexagonal shaft to align the flange adapters as they are installed. You can use a hammer, clamp, or press to push the nuts into place.