UCLA

Proprioception is the body’s sense of relative position and force in space. It is crucial for human movement planning and execution, as well as advanced control of robotic devices. In this dissertation, I explore this importance to both the myoelectric control of supernumerary robotic devices, as well as the impact of limiting ankle range of motion during walking on gait adaptation. First, I present an experiment on the impact of proprioception on myoelectric referred control performance, finding that individuals performed virtual and physical robotic tasks better when they were freely able to move their body and receiving position-based proprioception while controlling the referred devices. Then, I present a study on the impact of control mapping on referred control, showing that while using antagonist muscle pairs to control virtual degrees of freedom is important, not all antagonist pairings are equally as easy to use as others. In addition, I describe a study conducted on the feasibility of achieving differential activation of typically synergistic muscle compartments by leveraging proprioceptive feedback, finding that free space proprioceptive feedback enabled individuals to volitionally activate one side of their biceps brachii and not the other. Finally, I present a biomechanics experiment where participants walked on a treadmill at two level-ground speeds, up and down incline and decline settings, and up and down a staircase while wearing a passive exoskeleton that restricted ankle range of motion to discrete, predetermined values. Across different walking and range of motion conditions, it was consistently observed that individuals did not change their gait parameters to avoid contacting end-range hard stops, but that that ranges of motion at the ankle as small as ±10° are sufficient in preserving natural, uninhibited gait biomechanics.