Autonomous Soft Exosuit for Hip Extension Assistance

Abstract

In this abstract, we describe a mono-articular soft exosuit to assist with hip extension during overground walking. The system is comprised of a mobile Bowden-cable-driven electrical actuation unit, soft textiles, and a load cell and an inertia measurement unit per leg. The exosuit applies forces with a peak of 300 N enabled by an IMU-based iterative control algorithm. This iterative controller detects the onset timing of the hip extension assistance based on an estimation of the maximum hip flexion angle. The timing and magnitude of the applied peak force is modulated by generating step-by-step actuator position profiles based on the previously measured assistive force. Results from a human subject during overground walking at self-selected speed indicate the robustness of the system to apply effectively forces with a high consistency in terms of magnitude and timing of the peak force profile.