An approach for combining transparency and motion assistance of a lower body exoskeleton

TL;DR

This paper presents a novel method combining transparency and motion assistance in a lower body exoskeleton, using gear backlash and adaptive oscillators to improve gait support with promising initial results.

Contribution

It introduces a new approach that integrates transparency and adaptive assistance modes for exoskeletons, enhancing gait assistance through innovative control strategies.

Findings

Successful implementation of transparent mode with minimal perceived forces

Effective superimposed assistance guiding leg movement

Promising initial experimental results

Abstract

In this paper, an approach for gait assistance with a lower body exoskeleton is described. Two concepts, transparency and motion assistance, are combined. The transparent mode, where the system is following the user's free motion with a minimum of perceived interaction forces, is realized by exploiting the gear backlash of the actuation units. During walking a superimposed assistance mode applies an additional torque guiding the legs to their estimated future position. The concept of adaptive oscillators is utilized to learn the quasi-periodic signals typical for locomotion. First experiments showed promising results.