Lower-Limb Exoskeleton for Load-Carrying Augmentation

Abstract

Exoskeleton robots as a kind of wearable robots can assist or enhance people’s locomotion ability. In this paper, we present a lower-limb exoskeleton robot for load-carrying augmentation. The exoskeleton had 6 degrees of freedom (DOF) per leg, and two of DOF were powered by motors. Two geared motors were integrated at the hip joint to drive hip and knee joints by cables. The exoskeleton was anthropomorphically designed for better user experience. The STM32 hardware platform and the controller area network (CAN) bus were applied for signal processing and transmission, respectively. The control algorithm applied proportional derivative (PD) control algorithm based on gravity and friction compensations to achieve human-machine cooperation. At last, the exoskeleton prototype with 20kg payload capacity was successfully developed. The assistance efficiency was tested by the heart rate method. And the results showed that the assistance efficiency reached up to 79.45%.