Model-based control of skeletal muscle using musclecontraction models

Bioactuators using skeletal muscle are expected to be applied to medical and welfare equipment as functional materials with self-growth functions. In this regard, their contraction force must be controlled with high accuracy for the desired operation. Therefore, in this study, a model-based control method that follows the contraction force against an arbitrary reference contraction force is proposed to control the contraction of skeletal muscle. The muscle-contraction mechanism is modeled, and the stimulating voltage for exerting the desired contraction force is obtained using this model. Furthermore, the proposed method is validated experimentally using the gastrocnemius muscle of a toad. In the experiment, we identify muscle-contraction model parameters that can reproduce the contraction-force response of the gastrocnemius muscle from experimental data. Using the model, the stimulating voltage for exerting a reference is calculated. The voltage is applied to the gastrocnemius muscle of a toad to control the contraction force. The experimental results show that the proposed model-based control method can control muscle contractions even under a complicated reference contraction force. © (2024) The Japan Society of Mechanical Engineers. This is an open access article under the terms of the Creative Commons Attribution 4.0 International license (https://creativecommons.org/licenses/by/4.0/).