Study on impedance generation using an exoskeleton device for upper-limb rehabilitation

Rehabilitation robotics has been one of the most important branches of robotics. Particularly, the exoskeleton device for the upper limb rehabilitation develops fast in recent years, but most of them are heavy and large. In this paper, we proposed a light and wearable exoskeleton device which is potential to be used in home rehabilitation. It should be able to perform passive and active training. In this paper, we proposed a method to implement the active rehabilitation based on the upper limb exoskeleton rehabilitation device (ULERD). It provides a wide approach for human machine interface (HMI) in which the device is high friction and non-backdrivable, and meanwhile it is difficult to obtain the contact force information directly. The method is to measure the motion of human body other than the motion of device. It is implemented with passive DoFs unlocked during elbow flexion and extension performance. In contrast experiments, three level resistances are generated and provided to the user. The surface electromyography (sEMG) signals detected from biceps and triceps were recoded and processed to evaluate the effect of this method via wavelet packet transform (WPT).