Finite Horizon Nonlinear Energy Optimizing Control in a Force Augmenting Hybrid Exoskeleton for the Elbow Joint

In this brief, the implementation of a suboptimal nonlinear discrete control to optimize the energy consumption in a hybrid exoskeleton for the elbow joint is presented. The exoskeleton is used to amplify the strength of the user and is hybrid in the sense that it combines two types of actuators: pneumatic muscles and Harmonic Drive motors, which give power and precision to the system, respectively. The exoskeleton is autonomous in the energetic sense, and it is driven by compressed air and batteries. The suboptimal control is used to increase the operation time of the exoskeleton. This control law penalizes the energy consumption, and it has a direct effect on the operation time of the prototype.