CHS: Medium: Collaborative Research: Novel Optimal Control for Co-Adaptation of Human and Powered Lower Limb Prosthesis

新兴的动力假肢为恢复截肢者的正常运动提供了巨大的希望。然而，这些机器人设备目前缺乏佩戴者之间和佩戴者内部的适应性，无法应对佩戴者的身体变化和变化。临床上需要频繁的人工和启发式调整，这限制了这些先进假体的实际使用。为了更好地支持行走功能，提高截肢者的生活质量，需要智能、自适应、交互的新一代假肢控制。PI的长期研究目标是创造出能够适应单个截肢者的身体和认知能力，与佩戴者的运动和意图相协调，适应不断变化的环境，并从本质上恢复下肢损伤患者的全部功能的仿生腿。为此，PI在本项目中的目标是为这些假体创建一种新的最佳控制框架。他们将系统地解决这样的挑战，即支持佩戴者的身体能力的自动适应，同时实现集成截肢-假肢系统所需的步态性能。他们将为交互界面提供初步设计和评估，使佩戴者能够安全而轻松地个性化假肢控制。项目成果将开辟可穿戴机器人的新前沿，并为这些创新设备的临床翻译奠定基础，这不仅将影响假肢和矫形学行业，还将通过提供与人-机器人交互、生物力学和神经运动控制社区有关的新知识，通过阐明截肢者运动的控制机制，以及通过提供创新和经济高效的假肢解决方案，提供一般医疗保健。这项工作将引入的新的基于截肢-假肢性能的控制框架，代表着与主要专注于假肢(局部机器)设计的现有方法的背离，因为它采用了一种全球方法，考虑到截肢者和假肢之间的共同适应，以便根据佩戴者的身体状况提供最佳的个性化援助。PI将使用近似动态规划(ADP)来实现全局控制目标。ADP的这种创新使用将提供一个机会，在协同适应机器人假体的新测试领域展示其最佳自适应控制能力，这是一个独特而重大的挑战，只有在人类可穿戴机器人中才能看到，而在无生命的机器人中则看不到。ADP方案基于近似和学习，以缓解与准确建模佩戴者的神经肌肉控制和动力学相关的问题，这是很难实现的，如果不是不可能的话。此外，PIS将对经股截肢的受试者进行一项关于截肢者与假肢之间相互作用的实验研究，包括评估截肢者的补偿策略，以及评估假体控制中主观(人)和客观(机器)偏好之间的差异。

Emerging powered lower limb prostheses hold great promise for restoring normative locomotion in amputees. However, these robotic devices currently lack inter- and intra-wearer adaptability to cope with wearers' physical variations and changes. Frequent manual and heuristic adjustment in clinics is required, which limits the practical use of these advanced prostheses. A new generation of prosthesis control that is intelligent, adaptable, and interactive is needed to better support walking function and improve the quality of life of lower limb amputees. The PIs' long-term research goal is to create bionic legs that can adapt to the individual amputee's physical and cognitive capabilities, coordinate with the wearer's movement and intent, adjust to changing environments, and essentially restore the full function of patients with lower limb impairments. To this end, the PIs' objective in this project is to create a novel optimal control framework for these prostheses. They will systematically address the challenge of supporting automatic adaptation to the wearer's physical capability while achieving desired gait performance for the integrated amputee-prosthesis system. And they will provide a preliminary design and evaluation for an interactive interface that would allow wearers to personalize prosthesis control safely and easily. Project outcomes will open up a new frontier of wearable robotics and lay the foundation for clinical translations of these innovative devices, which will impact not only the prosthetics and orthotics industry but also the robotics community by providing new knowledge relating to human-robot interaction, the biomechanics and neuromotor control community by elucidating the control mechanism of amputee locomotion, and healthcare in general by providing innovative and cost-effective prosthesis solutions.The new amputee-prosthesis performance-based framework for control of powered lower limb prostheses which this work will introduce represents a departure from existing approaches that mainly focus on design for the prosthesis (a local machine), in that it adopts a global approach by accounting for co-adaptation between amputees and prostheses in order to provide optimal, personalized assistance based on wearers' physical conditions. The PIs will use approximate dynamic programming (ADP) to achieve the global control goal. Such innovative use of ADP will provide an opportunity to demonstrate its optimal adaptive control capability in a new test domain of co-adaptive robotic prosthesis, a unique and significant challenge only seen in human wearable robotics but not in lifeless robots. The ADP scheme is based on approximation and learning that alleviate problems associated with the requirement of accurately modeling wearers' neuromuscular control and dynamics that is difficult, if not impossible, to achieve. Additionally, the PIs will conduct an experimental investigation on subjects with transfemoral amputations of the interactions between amputees and prostheses, including evaluations of the compensatory strategies of amputees, and discrepancy assessment between subjective (human) and objective (machine) preferences in prosthesis control.