Task space control of normal & pathological locomotion

描述（由申请人提供）：本提案的广泛，长期目标是定量表征，比较和模拟由于下肢截肢而导致的正常和病理步态中任务空间控制的使用。广泛的研究详细的关节运动学和动力学的人类运动和运动控制与正常和各种运动功能障碍。然而，对于人类如何将关节水平的信息与更高水平的运动目标联系起来，我们知之甚少。了解损伤前后控制腿部的基本生物力学原理将为创建病理性步态障碍的新治疗干预措施提供一般的理论框架。本项目拟采用行为运动实验来研究健康完整的人类受试者以及使用假腿行走的膝下（经胫骨）和膝上（经股骨）截肢者的任务空间控制。该项目将使用广泛的数据分析，通过生物力学模型和特征分析确定变量，量化和表征运动过程中的任务空间控制。基于分析结果，进一步的研究将创建一个基于物理的病理截肢者步态的计算机模拟，并根据正常和截肢者步态之间的差异计算出纠正关节扭矩。该项目的一般假设是，人类通过精确地引导他们的腿通过预定义的任务空间来控制运动，同时允许关节水平动力学的灵活性，并且更多的近端肢体截肢将导致更大的损失这种利用任务空间冗余的能力。研究在运动过程中使用任务空间控制的三个具体目标：正常的人类运动（目标1）；下肢截肢病理步态（Aim2）；评估和模拟正常到病理人类行走的变化（Aim3）。实现这三个目标将通过量化正常人类步态的功能相关任务变量和对神经力学病理（如下肢截肢）后这些控制变量如何变化的理论理解，提供即时交付成果。这项工作将开发新的分析工具来定量分析正常和截肢者的步态，然而，它也将普遍适用于所有步态病理的研究。它可以进一步影响未来使用任务级而不是关节级康复目标的步态康复治疗方法，并为快速发展的康复机器人设备领域提供控制系统。提出的工作也将为未来研究运动过程中腿部控制的神经机制提供理论框架。

DESCRIPTION (provided by applicant): The broad, long-term objectives of this proposal are to quantitatively characterize, compare, and simulate the use of task space control in normal and pathological gait due to lower limb amputation. Extensive research has detailed joint kinematics and kinetics of human locomotion and movement control with normal and various motor function disorders. Yet, relatively little is known about how humans relate joint-level information to higher-level locomotor goals. Understanding basic biomechanical tenets governing leg control before and after injury will provide a general theoretical framework for creating new therapeutic interventions for pathological gait disabilities. This project proposes to use behavioral locomotion experiments to study task space control in both healthy intact human subjects and in both Below-Knee (transtibial) and Above-Knee (transfemoral) amputees walking on prosthetic legs. This project will use extensive data analysis to quantify and characterize task space control during locomotion using variables identified from biomechanical models and by eigenanalysis. Based on the analytical results, a further study will create a physics-based computer simulation of pathological amputee gait with corrective joint torques computed from the differences discovered between normal and amputee gait. The general hypothesis of the project is that humans control locomotion by precisely guiding their legs through a predefined task space while allowing flexibility in joint-level dynamics and that more proximal limb amputations will result in greater losses in this ability to exploit task space redundancy. Three specific aims to study the use of task space control during locomotion are addressed: normal human locomotion (Aim1); pathological gait due to lower limb amputation (Aim2); and, the evaluation and simulation of the changes from normal to pathological human walking (Aim3). Achieving these three aims will provide immediate deliverables by quantifying functionally relevant task variables for normal human gait and a theoretical understanding of how these control variables change after a neuromechanical pathology such as lower limb amputation. This work will develop new analytical tools to quantitatively assay normal and amputee gait, however, it will also be generally applicable to the study of all gait pathologies. It could further impact future therapeutic approaches for gait rehabilitation that use task-level rather than joint-level rehabilitation goals and inspire control systems for the rapidly growing field of rehabilitative robotic devices. The proposed work will also form a theoretical framework for future studies of the neural mechanisms underlying leg control during locomotion.