Design and Biomechanical Evaluation of a Lightweight Low-Complexity Soft Bilateral Ankle Exoskeleton

2026-02-20

AI Summary

This study addresses the gait interference commonly caused by the added mass and rigid structures of conventional exoskeletons. To overcome this limitation, the authors propose a lightweight, low-complexity soft bilateral ankle exoskeleton that delivers plantarflexion assistance through an integrated shoe-upper design, ensuring compatibility with arbitrary footwear. The system combines a compliant mechanical structure with a universal shoe-mounted mechanism and a customized control algorithm, and its biomechanical impact is evaluated under zero-torque mode. Experimental results demonstrate that the device imposes no significant alterations on lower-limb kinematics or kinetics in healthy subjects, thereby confirming its non-intrusive nature and wearability. This work establishes a novel paradigm for gait assistance characterized by high compatibility and minimal interference with natural locomotion.

Technology Category

• Intelligent Robots: Motion and Path Planning
• Humans and AI: Interaction Techniques and Devices
• Multiagent Systems: Mechanism Design

Application Category

• Responsible Web: Machine-in-the-loop, human agency and autonomy
• Social Networks and Social Media: Generative AI / large language models and their impact on social systems
• User Modeling, Personalization and Recommendation: Accountability, Transparency, and Ethics for personalization

Abstract

Many people could benefit from exoskeleton assistance during gait, for either medical or nonmedical purposes. But exoskeletons bring added mass and structure, which in turn require compensating for. In this work, we present a lightweight, low-complexity, soft bilateral ankle exoskeleton for plantarflexion assistance, with a shoe attachment design that can be mounted on top of any pair of shoes. Experimental tests show no significant difference in lower limb kinematics and kinetics when wearing the exoskeleton in zero-torque mode relative to not wearing an exoskeleton, showing that our device does not obstruct healthy gait, and proving it as a compliant and comfortable device, promising to provide effective assistance. Hence, a control system was developed, and additional tests are underway.

Problem

• exoskeleton
• gait assistance
• ankle exoskeleton
• added mass
• biomechanical interference

Innovation

• soft exoskeleton
• ankle assistance
• lightweight design
• shoe-mounted
• compliant wearable