The Influence of Co-Contraction to the Arm Impedance During Free Planar Movement

Enlightened by the disparity between the experimental and theoretical calculations of flexion and extension muscle activities, this paper proposes that co-contraction contributes to arm impedance control even during free planar movements. Therefore, the proposal above, implemented with the neuro-muscle-skeleton model and optimal control tool, could yield stiffness ellipses which are consistent with experimental data and reduce discrepancy of the original model.