Improving gait performance of transtibial amputees through bioinspired design of personalized controllers for active prostheses

Healthy individuals walk seemingly effortless but failure to restore locomotion after amputation reveals how challenging this task is. Amputated body parts do not contribute to gait propulsion or stability, leading to reduced walking performance. Active prostheses emerged to address the loss of propulsive capacity. Although active devices are capable of providing the mechanical work needed for locomotion, they fail at restoring walking performance. We hypothesize that current active prostheses fail at restoring gait performance because their control is incompatible with amputee movement strategies. Besides motor function, amputees lack feedback from the amputated limb segments which is crucial for balance control. Therefore, prosthesis controllers that are designed to reduce the metabolic cost of walking might not be effective for amputees who prioritize stability. In addition, there might be large inter-subject differences in how much individuals prioritize stability over effort. The goal of this project is to design and validate controllers for active prostheses that optimize the synergetic user-prosthesis behavior for transtibial amputees. We will use computational and experimental approaches. We will develop a simulation framework to design prosthesis controllers that optimize walking performance according to the user’s stability preferences. Controller design will be inspired by insights in human balance control derived from experimental observations.