Control of bio-actuators based on muscle contraction models

For the industrial application of bio-actuators, the realization of bio-actuator requires the technology to precisely control the contraction of skeletal muscle. Therefore, this research proposed a model-based control method. This control method allows skeletal muscles to exert any contraction forces, as well as the conventional tension/relaxation control. First, we developed the method to optimize the stimulation voltage that causes the bio-actuator to move as per the reference contraction force, through model-based calculation. Moreover, we built a prototype bio-actuator driven by a frog’s skeletal muscle and conducted experiments to test the validity of this method. In this experiment, muscle contraction model parameters were identified so that the behavior of the actuator was reproduced from the muscle contraction models before control. Subsequently, based on this model, the actuator was controlled by the proposed control method. As a result, the output of the actuator could be roughly matched to the reference force. The results demonstrate the potential of the proposed method to achieve precise control of bio-actuators.