Passivity Based Control in Bipedal Locomotion

摘要本课题旨在研究基于被动控制的双足运动控制。近年来，基于被动的控制已被证明是机电系统控制中最强大的设计方法之一，如机器人操纵器、水下航行器、感应电机、汽车和航空航天系统等。除了少数例外，这些方法在步行机器人和其他有影响的系统中的应用尚未得到充分的研究。该项目将在基于被动混合非线性控制的背景下探索双足运动的几个扩展。该项目将研究速度调节，使用交替势函数来增加稳定极限环的吸引力盆地，基于被动控制的控制饱和和欠驱动的影响，以及基于被动的控制方法与真能量最优控制相比的效率。它还将研究基于被动的步态转换控制，包括开始和停止。该项目的目标和技术优点是通过分析、开发新概念和设计可证明正确的控制算法来帮助巩固该领域的基础。该项目的另一个方面是将基于被动性的分析和控制的理论工具与人类受试者的平衡和运动研究相结合，以便用更多的分析方法补充这些研究中典型的描述性研究。这个研究项目的实际应用是在行走机器人的设计上，它比现有的机器有更好的性能能力。目前的步行机器人由于能量利用率低，行走范围有限，并且在崎岖地形上的导航能力有限。一旦将现有理论工具的全部力量用于本项目的分析和设计问题，就会产生更实用、更高效的步行机。从更广泛的角度来看，这项研究的应用将超出改进步行机的设计。在这个项目中开发的分析和设计工具也将有助于更好地理解人类运动，这将导致生物力学和生物医学的应用，如设计改进的假肢装置，开发老年人跌倒预防计划和康复技术。仅在美国，老年人跌倒对经济的影响每年就超过100亿美元，包括医疗账单和其他费用。该项目改进的建模和分析工具将应用于从人类受试者获得的真实数据，以了解衰老如何影响平衡和运动，以及如何开发干预技术以减少跌倒率。

AbstractThis project is to investigate passivity based control in bipedal locomotion. In recent years, passivity based control has proven to be one of the most powerful design methodologies for the control of electromechanical systems such as robot manipulators, underwater vehicles, induction motors, automotive and aerospace systems, and others. With a few exceptions the application of these methods to walking robots and other systems with impacts has not been adequately investigated. The project will explore several extensions of bipedal locomotion in the context of passivity based hybrid nonlinear control. The project will investigate speed regulation, the use of alternate potential functions to increase the basins of attraction of stable limit cycles, the effect of control saturation and under actuation in passivity based control, and the efficiency of passivity based control methods compared to true energy optimal control. It will also investigate passivity based control of gait transitions, including starting and stopping. The goal, and the technical merit of the project, is to help solidify the foundations of the field through analysis, development of new concepts, and the design of provably correct control algorithms. Another aspect of the project is to integrate the theoretical tools of passivity based analysis and control with studies of balance and locomotion in human subjects in order to supplement the descriptive research typical in those studies with more analytical methods.The practical application of this research project is on the design of walking robots that have improved performance capabilities over existing machines. Current walking robots have limited range due to poor energy utilization and are limited in their ability to navigate rough terrain. More practical and more efficient walking machines will result once the full power of available theoretical tools is brought to bear on the analysis and design questions in this project. From a broader perspective, the applications of this research will extend beyond the design of improved walking machines. The analysis and design tools developed in this project will also contribute to a better understanding of human locomotion, which will result in applications in biomechanics and biomedicine, such as the design of improved prosthetic devices, the development of falls prevention programs for the elderly, and rehabilitation techniques. The impact of falls among the elderly in the United States alone has a yearly impact on the economy of more than ten billion dollars in medical bills and other expenses. The improved modeling and analysis tools of this project will be applied to real data obtained from human subjects in order to understand not only how aging affects balance and locomotion, but also how to develop intervention techniques to decrease the rate of falls.