Design and Model-Based Safety Verification of a Volitional Sit-Stand Controller for a Powered Knee-Ankle Prosthesis

动力膝踝假肢自主坐站控制器的设计和基于模型的安全验证

基本信息

批准号：
10388466
负责人：
Daphna Raquel Raz
金额：
$ 4.06万
依托单位：
UNIVERSITY OF MICHIGAN AT ANN ARBOR
依托单位国家：
美国
项目类别：
财政年份：
2022
资助国家：
美国
起止时间：
2022-03-01 至 2024-02-29
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/10388466
关键词：
Address Adopted Adoption American Amputation Amputees Area Artificial Leg Back Pain Behavior Benchmarking Biological Certification Characteristics Communities Computer Systems Computer software Data Set Development Device Safety Device or Instrument Development Devices Dimensions Ensure Environment Equipment Exhibits Failure Feedback Force of Gravity Formulation Gait Goals High Performance Computing Hip region structure Human Individual Infrastructure Infusion Pumps Institutes Joints Knee Leg Link Literature Lower Extremity Mathematical Model Simulation Mathematics Measures Mechanics Medical Device Medical Device Safety Medical center Mentorship Methods Michigan Mission Modeling Motion Movement Muscle National Institute of Biomedical Imaging and Bioengineering National Institute of Child Health and Human Development Outcome Pacemakers Performance Phase Physics Procedures Process Production Program Development Prosthesis Public Health Quality of life Research Residual state Risk Robotics Safety Side Source System Techniques Testing Thigh structure Torque Training Universities Validation Volition Walking Work ankle prosthesis base career clinical application cluster computing computing resources design falls human subject improved insight kinematics mathematical algorithm meetings novel patient mobility powered prosthesis programs prosthesis wearer rehabilitation research simulation sound technology development time interval tool

项目摘要

ABSTRACT Sit-stand transitions, the motions executed by individuals to stand up or sit down, are an important determinant of overall mobility and a common source of falls. Unilateral amputees using standard passive prostheses are further challenged by sit-stand transitions due to muscle and joint asymmetries they exhibit between the sound and amputated sides, often resulting in debilitating back pain. Powered knee-ankle prostheses can produce enough torque to assist meaningfully during sit-stand transitions and can meet design criteria such as producing smooth motion on the amputated side that matches the sound side. Controllers for these prostheses can be designed to allow user-driven control of the leg. However, the production of high torques not directly commanded by the user comes with increased risks. This is of particular concern because these legs must be adopted outside of controlled lab environments. Thus, any powered prosthesis must demonstrably meet design and safety criteria. While safety-critical medical devices, such as pacemakers, are subjected to extensive testing and validation procedures, there is no agreed-upon standard in the powered prosthetics field for how to define and measure safety. Prior work on sit-stand controllers has focused only on measuring a limited number of outcomes with respect to one design criterion on a small number of subjects, providing no guarantees about safety. The set of techniques known as formal verification provides powerful tools to reason about the behavior of systems that are composed of interacting mechanical, software, and biological modules. Given a model of a system, formal verification allows us to probe the system’s behavior over an infinite range of possibilities that cannot be replicated in the lab during a typical testing session. These methods can then guide real-world testing, and alert system designers to problematic regions of execution. In this project, I propose to apply formal verification techniques to design a volitional controller for sit-stand transitions with provable safety guarantees, using physics-based models and novel mathematical formulations of safety. The University of Michigan Robotics Institute is one of the top institutes of its kind in the US and provides an ideal environment and infrastructure for the successful completion of this research. The Robotics Institute gait lab has all of the necessary equipment needed for powered prosthesis research, including two state-of-the-art prosthetic legs, and access to advanced computational resources such as the Great Lakes high performance computing cluster. Drs. Gregg and Ozay have proven expertise relevant to the aims of this project, and will provide mentorship that will guide my research, my training, and the attainment of my career goals.

抽象的坐站转换，即个人站起来或坐下的动作，是一个重要的决定因素整体活动能力下降和使用标准被动假肢的单侧截肢者跌倒的常见原因。由于声音之间表现出的肌肉和关节不对称，坐站转换进一步受到挑战和截肢，通常会导致使人衰弱的背痛。足够的扭矩可以在坐站转换过程中提供有意义的帮助，并且可以满足设计标准，例如在截肢侧产生与这些假肢的健全侧相匹配的平滑运动。可以设计成允许用户驱动控制腿，但是不能直接产生高扭矩。由用户指挥会带来更大的风险，这是特别值得关注的，因为这些腿必须受到限制。因此，任何动力假肢都必须明显符合设计要求。而起搏器等安全关键型医疗设备则受到广泛的考验。测试和验证程序，在动力假肢领域没有商定的标准来说明如何定义和测量安全性之前有关坐站控制器的工作仅集中于测量有限的数量。针对少数受试者的一项设计标准的结果，不提供任何保证安全性称为形式验证的一组技术提供了强大的工具来推理行为。由相互作用的机械、软件和生物模块组成的系统。对于系统，形式化验证使我们能够在无限的可能性范围内探索系统的行为在典型的测试过程中无法在实验室中复制这些方法，然后可以指导现实世界。测试区域，并提醒系统设计者注意执行问题。在这个项目中，我建议应用。形式化验证技术，设计用于坐站转换的意志控制器，并具有可证明的安全性使用基于物理的模型和新颖的安全数学公式来保证。密歇根大学机器人研究所是美国同类顶尖研究所之一，提供机器人研究所步态研究的成功完成的理想环境和基础设施。实验室拥有动力假肢研究所需的所有必要设备，包括两台最先进的设备假肢，并获得先进的计算资源，例如五大湖高性能 Gregg 和 Ozay 博士拥有与该项目目标相关的专业知识，并将提供指导，指导我的研究、培训和实现我的职业目标。