2016 Volume 19 Issue 2 Pages 8-16
The existence of bi-articular muscles greatly contributes to hybrid position and force control, and compliance control of the end point of extremities. In electromyography, the coordinated activity pattern of three pairs of antagonistic muscles, consisting of mono- and bi- articular muscles, contributed to control of the output force direction, and the output distribution at maximum effort was a hexagonal shape with the muscular strength for each pair of antagonistic muscles. In mechanical human leg model experiments, we demonstrated that the parallel link mechanism of a bi- articular muscle along the posterior crus was involved in stabilizing a jumping motion, and that the coordinated contraction mechanism of three pairs of antagonistic muscles in the femoral region contributed to absorbing the force generated during the landing motion. The results obtained from the mechanical leg model experiments strongly suggest that coordinated muscular functions could provide rapid and precise human like movements without a feedback control system.
