Synergy-based myocontrol of a two degree of freedom robotic arm in children with dystonia

We tested the ability of a synergy-based myocontrol scheme to achieve simultaneous, continuous control of two degrees of freedom (DOFs) of a robotic arm that reproduces the child’s movement (or intention of movement), using muscle synergies extracted from muscles recorded during both isometric contractions and unconstrained flexion-extension movements of elbow and shoulder joints in the horizontal plane. The aim of the current work was to validate the feasibility and the efficacy of the synergy-based approach for multi-DOF robotic control in children with dystonia, compared to the simple muscle-pair method typically used in commercial applications. The proposed synergy-based scheme showed a better performance compared to the traditional muscle-pair approach, both in dynamic and isometric conditions. The current study represents a crucial successful first step toward synergy-based working solutions for children with dystonia.