Robotic Amputated Lower Limb for In-vitro Testing of Osseointegrated Prostheses Devices

This paper presents the design and control of a robotic amputated lower limb gait simulation rig to aid in the development, in-vitro testing and validation of smart devices that can enhance osseointegrated prosthesis implants. A single degree-of-freedom design capable of simulating the motion of post-traumatic residual limb was developed to replicate gait patterns obtained from motion capture data. A realistic limb model that replicates both the dimensions and the mass of a residual limb was integrated in the gait simulation rig. The modular architecture of the robotic limb allows swapping of the model limb to accommodate physical variation between patients. Using a gain-scheduled controller architecture, the desired trajectory of this synthetic amputated limb was achieved. A rotary encoder was used to provide feedback to the onboard controller and the performance of this robotic limb was evaluated by adding a sensor array to establish the feasibility of using this rig in testing of newer osseointegrated prosthesis devices.