Nguyen Harrison, Shallal Christopher, Thakor Nitish
IEEE Int Conf Rehabil Robot. 2019 Jun;2019:1266-1271. doi: 10.1109/ICORR.2019.8779413.
Amputees often find wearing a prosthetic limb for a long period of time uncomfortable. Prosthetic sockets that adjust the socket's fit automatically, or adaptive sockets, would encourage amputees to wear their prosthesis more frequently. In this work, we simulate the control system design of a Multiple-Input, Multiple-Output (MIMO) adaptive socket using principles of optimal control and robust control. A data-driven model of the socket-limb interface is first obtained by applying regression to open-loop recordings of the socket interacting with the limb during a simulated grasping task. A MIMO controller is then designed to maintain a desired uniform socket fit. An $H_{\infty}$ controller, obtained from loop shaping synthesis using the Glover-McFarlane method, is shown to perform comparably to a Linear Quadratic Gaussian (LQG) controller while maintaining robustness to uncertainties in the socket-limb interface model. This work then outlines a potential procedure on how to develop the control system for a real adaptive prosthetic socket with multiple sensors and actuators.
截肢者常常觉得长时间佩戴假肢很不舒服。能够自动调整适配度的假肢接受腔，即自适应接受腔，会促使截肢者更频繁地佩戴假肢。在这项工作中，我们运用最优控制和鲁棒控制原理模拟了多输入多输出（MIMO）自适应接受腔的控制系统设计。首先，通过对模拟抓握任务期间接受腔与肢体相互作用的开环记录进行回归分析，获得了接受腔 - 肢体界面的数据驱动模型。然后设计一个MIMO控制器来维持所需的均匀接受腔适配度。通过使用格洛弗 - 麦克法兰方法进行回路成形综合得到的 $H_{\infty}$ 控制器，在保持对接受腔 - 肢体界面模型不确定性的鲁棒性的同时，表现得与线性二次高斯（LQG）控制器相当。这项工作随后概述了一个关于如何为具有多个传感器和致动器的实际自适应假肢接受腔开发控制系统的潜在程序。
