A Study on Speed Control for Assisting Unit of Wheeled Walking Frames

近年来，在老龄化社会中，人们对轮式步行架的期望越来越高。轮式步行架是老年人或残疾人在康复中使用的辅助设备。轮式步行架有室内式和室外式两种。户外类型使用带着行李走路的困难的人或通常使用手杖的人。医院或机构室内步行架是大多数康复治疗的高辅助设备。两种传统的轮式步行架在上/下斜坡上行走都有缺点。人们在向上行走时经常需要动力辅助，在向下行走时需要安全的行走支撑而不会摔倒。本研究的目的是利用广义内模控制（IMC）设计结构来解决现有轮式步行架存在的这些问题。因此，我们开发了一种用于轮式步行架辅助单元的速度控制系统。IMC设计在工业控制技术中有着广泛的应用。采用LQ控制的广义内模控制设计结构对轮式步行架的速度控制具有一定的挑战性。该方法是基于一种采用观测器稳定化控制器的二自由度伺服系统。该控制方法通过伺服补偿实现了良好的干扰解耦和轨迹跟踪性能。实验结果表明，带伺服补偿的广义内模控制对轮式步行架辅助单元的速度控制是有效的。该方法的扰动解耦特性对上下坡的扰动解耦效果明显。我们相信辅助单元对需要轮式步行架的人是有帮助和有用的。老年人或残疾人将使用轮式步行，以便独立生活。

In the aging society of recent years, the expectation for the wheeled walking frames increases. Wheeled walking frames are supporting equipments, to be used by elderly people or handicapped in rehabilitation. Wheeled walking frames have indoors type and outdoors type. The outdoor type uses the difficult person who walking with luggage or the person who is usually using the stick. The indoor type walking frames for hospital or institution is high supporting equipments for mostly rehabilitation. Both conventional wheeled walking frames have weakness in walking on upward / downward slope. People often need power assistance on upward, and need secure walking support without falling on downward.The purpose of this study is to solve these problems of current wheeled walking frames by using the generalized internal model control (IMC) design structure. Therefore, we develop a speed control for assisting unit of wheeled walking frames. The IMC design is widely used in industrial control technology. The control application to speed control of wheeled walking frames would be challenging by using the generalized IMC design structure with LQ control.The proposed method is based on a two-degree-of-freedom servo system using an observer-based stabilizing controller. The control method achieves good disturbance decoupling and good trajectory tracking performance with servo compensation. The experimental results showed that the generalized IMC with servo compensation was effective to speed control of the assisting unit for the wheeled walking frames. The disturbance decoupling property of the proposed method effects especially on going upward and downward slope.We believe that the assisting unit is helpful and useful for people who need the wheeled walking frames. The wheeled walking will be used by elderly or disable people in order to live independently.