High bandwidth attitude control based on musculoskeletal system with biarticular muscles

It is a quite wondering fact that all land animals and humans have biarticular muscles although the extra biarticular mechanism seems unnecessary in engineering view. This research investigates the contribution of biarticular muscles in living organisms to the attitude control. A method of angular stiffness calculation is proposed and the maximum angular stiffness of each musculoskeletal model is estimated based on the method. It is shown that the model with biarticular muscles can set higher angular stiffness without increasing the total mass of actuators. Furtheremore, experimental results show that control bandwidth is extended due to the high stiffness property.