Abstract
This paper is concerned with modeling of water hydraulic McKibben muscle. In particular, linear system identification technique is applied to the muscle in order to obtain a muscle dynamic model. However, the muscle has nonlinearity such as hysteresis and saturation characteristics. It is difficult to express the nonlinearity using linear system identification because the linear model is assumed. Then we propose the introduction of Bouc-Wen model which is widely used for expression of hysteresis characteristics for the identified muscle model. The application of Bouc-Wen model is easy because of the structure of the identified model and the proposed muscle model has good agreement with experimental results. In addition, the model for gait-training taking into consideration of its operation range can be obtained. Applying to limited operation range, the performance of the identified muscle model is improved and then the model which can express hysteresis and saturation characteristics can be obtained.
