Design and Manufacturing of a Hand-and-Wrist Exoskeleton Prototype for the Rehabilitation of Post-Stroke Patients

In the field of robot-aided neuro-rehabilitation, the “BRAVO” project aims at defining a new approach to the development of assistive and rehabilitative robots for upper limb motor-impaired users, in order to perform complex visuomotor tasks. Within this framework the authors designed and manufactured the distal part of the overall exoskeleton, i.e. the hand-and-wrist system. The hand exoskeleton has 2 degrees of freedom (DOFs) for the flexion/extension of the thumb and for the flexion/extension of the group composed by the other four fingers. The functions of opening and closing is controlled by the patient’s brain signals detected via a brain-computer interface. The wrist unit has 2 DOFs for the actuation of the prono-supination and flexion/extension movements. The arm exoskeleton and the wrist unit are controlled through a complex scheme involving trajectory planning (based on the patient’s current gaze) and a hybrid position/force control. This paper outlines the scope of the entire project and illustrates the development of the wrist-and-hand exoskeleton prototype.