Dynamic Assistance for Human Balancing with Inertia of a Wearable Robotic Appendage

A reduced balance ability can lead to falls and critical injuries. To prevent falls, humans use reaction forces and torques generated by swinging their arms. In animals, we can find that a similar strategy is taken using tails. Inspired by these strategies, we propose an approach that utilizes a robotic appendage as a human balance supporter without assistance from environmental contact. As a proof of concept, we developed a wearable robotic appendage that has one actuated degree of freedom and rotates around the sagittal axis of the wearer. To validate the feasibility of our proposed approach, we conducted an evaluation experiment with human subjects. Controlling the robotic appendage we developed improved the subjects' balance ability and enabled the subject to withstand up to 22.8 % larger impulse disturbances on average than in the fixed appendage condition.