It has been found that magneto-rheological (MR) devices can produce large controllable force/torque while consuming little power. In this research, an MR actuator that can function as a clutch or a brake is developed, in order to be applied to an assistive knee brace. The torque capability and dynamic characteristics of the MR actuator are evaluated. The relationship between the torque output and the applied coil current is given. The response time is also measured. Experimental results show that the MR actuator can provide enough torque for normal activities with sufficiently fast response. IP control and adaptive control are proposed to control the MR actuator. Experiments under these controls are carried out. With anti-windup strategies, both controls achieve good performances. However, adaptive control would be more promising since it can adapt to parameter variations and maintain good performance. An assistive knee brace that contains this MR actuator and a DC motor is developed. In order to study the performances of the knee brace before applied to human body, experiments are conducted for evaluation under a custom-built testing structure. IP-based state control and adaptive control are used to control both the MR actuator and DC motor. Experimental results demonstrate that the MR actuator and DC motor work well together to provide assistance as expected. Compared with that without MR actuator, the evaluation results show that the knee brace with MR actuator is more energy efficient during normal walking, while having better force controllability and safety. / by Chen, Jinzhou. / Adviser: Liao Wei Hsin. / Source: Dissertation Abstracts International, Volume: 73-01, Section: B, page: . / Thesis (Ph.D.)--Chinese University of Hong Kong, 2009. / Includes bibliographical references (leaves 140-151). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [201-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract also in Chinese.
| Identifer | oai:union.ndltd.org:cuhk.edu.hk/oai:cuhk-dr:cuhk_344600 |
| Date | January 2009 |
| Contributors | Chen, Jinzhou., Chinese University of Hong Kong Graduate School. Division of Automation and Computer-Aided Engineering. |
| Source Sets | The Chinese University of Hong Kong |
| Language | English, Chinese |
| Detected Language | English |
| Type | Text, theses |
| Format | electronic resource, microform, microfiche, 1 online resource (xii, 154 leaves : ill.) |
| Rights | Use of this resource is governed by the terms and conditions of the Creative Commons “Attribution-NonCommercial-NoDerivatives 4.0 International” License (http://creativecommons.org/licenses/by-nc-nd/4.0/) |
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