Development of a physiological knee motion simulator

• Published in: Advanced robotics 1999-01, Vol.13 (2), p.171-188
• Main Authors: KIGUCHI, K, FUKUDA, T, KOGA, Y, WATANABE, T, TERAJIMA, K, HAYASHI, T, SAKAMOTO, M, MATSUEDA, M, SUZUKI, Y, SEGAWA, H
• Format: Article
• Language: English
• Subjects: Applied sciences; Backpropagation; Biomechanics; Computer science; control theory; systems; Control theory. Systems; Exact sciences and technology; Fuzzy control; Intelligent control; Learning algorithms; Neural networks; Physiological models; Robot learning; Robotics; Simulators
• ISSN: 0169-1864; 1568-5535
• DOI: 10.1163/156855399X01071

Several kinds of knee motion simulator systems have been developed for the accurate analysis of knee biomechanics. Knee motion simulators, however, are not recognized for their practical use because of difficulties in design and control. In this study, a wire-driven knee simulator which generates physiological knee motion has been developed. Physiological three-dimensional tibia motion against the femur can be generated by the simulator. Many clinical studies have been performed to analyze the length displacement pattern of the anterior cruciate ligament (ACL) and the posterior cruciate ligament (PCL). We assume that the physiological knee motion can be realized if the length displacement patterns of the ACL and PCL against the knee flexion angle are the same as the experimental data obtained from the literature. A fuzzy neural control policy, one of the most effective intelligent control policies, has been applied for control of the simulator. Applying the fuzzy neural control policy, human knowledge and experience can be reflected and adaptive/learning ability can be incorporated in the controller. On-line learning of the fuzzy neural controller is carried out to minimize a fuzzy controlled evaluation function using the back-propagation learning algorithm. The effectiveness of the proposed simulator has been evaluated by experiments using a model bone.