Learning a Speed-adaptive Hip Exoskeleton Control Policy Via Sim-to-real Reinforcement Learning

2026-09-23

AI Summary

研究通过结合仿真到现实强化学习与在线偏好学习，解决个性化外骨骼辅助在不同行走速度下的适应性问题。

Abstract

Providing personalized exoskeleton assistance across varying walking speeds remains challenging. Existing online optimization methods are sample-inefficient, requiring extensive human-in-the-loop (HIL) evaluations to optimize the entire assistive torque profile. Sim-to-real reinforcement learning (RL) offers a promising alternative but cannot directly account for individual user preferences. We propose a framework integrating sim-to-real RL with online preference learning for personalized exoskeleton assistance. Specifically, assistance timing is learned in simulation by training RL policies with human musculoskeletal models across varying walking speeds. The learned policies are then distilled and deployed on a physical hip exoskeleton using onboard sensory observations. Gaussian-process-based preference learning further personalizes the assistance magnitude through pairwise user comparisons. By decoupling assistance timing learning in simulation from magnitude optimization in real-world experiments, our framework substantially reduces the online optimization space. Human-subject experiments demonstrate efficient identification of personalized assistive torque profiles across varying walking speeds with fewer real-world evaluations.

Problem

• personalized exoskeleton assistance
• walking speeds
• sample-inefficient
• human-in-the-loop evaluations
• assistive torque profile

Innovation

• sim-to-real reinforcement learning
• online preference learning
• personalized exoskeleton assistance
• Gaussian-process-based preference learning