Novel Lightweight Lower Limb Exoskeleton Design for Single-Motor Sequential Assistance of Knee & Ankle Joints in Real World

In this article, we introduce a lightweight lower limb exoskeleton that provides auxiliary torque to both the ankle and knee joints during the stance phase of gait in a real-world environment, using one quasi-direct-drive (QDD) motor .This lightweight exoskeleton incorporates a novel driving mechanism: the Unidirectional Ankle-Knee Gait Clutch (UAKC), which allows for the sequential provision of auxiliary torque to the knee and ankle joints during the stance phase of gait. We trained a lightweight convolutional neural network to determine gait phases from scanned insole pressure data and generate corresponding biological torques. We provide a detailed exposition of the design concept and operation of the lightweight exoskeleton. Through a series of experiments, we evaluated the performance of the lightweight exoskeleton. In real-world conditions, it reduced human energy consumption by 8.9 +/- 1.3% compared to walking without the exoskeleton.This study reports on the potential of this rigid-cable coupled underactuated exoskeleton in enhancing human movement.