Design and Preliminary Testing for a Unilateral Hip Exoskeleton.

In this paper, we design a unilateral hip exoskeleton and conduct preliminary experiments to assist people to walk. The exoskeleton aims to help those people whose physical strength is weak. The design of the hip exoskeleton focuses on the light weight, the ease of use and the comfort of wearing. This adjustable output feedback-based control strategy is only dependent on the output feedback information from the mechanical exoskeleton. The feedback information is obtained only from the position encoder attached to the electrical encoder. The proposed approach produces a control input variable based on the dynamic model directly. Estimation of disturbances in robotic systems by means of Extended State Observers(ESO). The Kalman filter is employed to process the control input variable to provide smooth movement for the hip exoskeleton. The controller offers an immediate and smooth transition among different movement directions.Then, we experimentally verified the efficacy of the hip exoskeleton as an assistive controller. Three human subjects wear hip exoskeleton and walk on the flat ground. The auxiliary torque and power generated by different human subject were tested and analysed to show the versatility of the controller.