Design Process of Exoskeleton Rehabilitation Device and Implementation of Bilateral Upper Limb Motor Movement

With the development of neurorehabilitation, physical rehabilitation strategies for the upper limbs have become gradually accepted by therapists and researchers. These strategies include intensive intervention, task-oriented training, and bilateral training. Most upper limb rehabilitation systems have been developed for unilateral training. This paper develops an upper limb exoskeleton rehabilitation device (ULERD) that can be used for bilateral training. The device has three active degrees of freedom (DoFs) in the elbow and wrist joints, and an additional four passive DoFs at these joints to correct any misalignment between the human and device joints. A bilateral training strategy is implemented with the developed ULERD and a haptic device according to neurorehabilitation theory. In a preliminary study, a healthy user was able to manipulate the haptic device with one hand (intact hand for hemiplegic patients) when the upper arm was fixed, and the ULERD assisted in moving the other hand (impaired upper limb for hemiplegic patients). To implement bilateral training, the kinematics of one upper limb (intact limb) and the haptic device is analyzed, respectively. The angles of the three active DoFs are determined via integration. An inertia sensor is used to evaluate the kinematics resolution. The ULERD was evaluated by experienced therapists during the design process to determine its potential for clinic application. Experimental results indicate that the kinematics resolution is effective and that this type of bilateral movement can be implemented using the ULERD and the haptic device.