Hand exoskeleton for rehabilitation and functionalization

Abstract

Many diseases and injuries of the hand require rehabilitation to restore function. However, the high human, financial, spatial, and temporal costs associated with rehabilitation often mean that the population in need does not have access to optimal rehabilitative care. Therefore, devices that complement the therapist are a possible solution, as they make rehabilitation more independent and frequent, and save healthcare facilities the aforementioned resources. Nevertheless, these devices are not widely distributed in the market, mainly due to their poor accessibility. The newly designed exoskeleton has four motors and a redundant transmission system that allows independent flexion and extension of each finger, except the thumb. Kinematics were analyzed with motion studies and loads were evaluated with static studies and structural analysis using motion loads. In the simulations, both flexion and extension were achieved in four seconds. A prototype transmission system was built and its kinematics matched that of the simulation and corresponded to the biomechanics of the fingers. At maximum flexion, the exoskeleton would be able to hold small objects and exert a normal force of up to 20 N with structural integrity.