A hand exoskeleton device for robot assisted sensory-motor training after stroke

Robot assisted rehabilitation devices are becoming popular for stroke rehabilitation, but they are mainly highlighted in training and recovery of motor function. This paper describes the development of a hand exoskeleton rehabilitation device which focuses not only on rehabilitation of motor function, but also sensory training and stimulation. The device was designed to enable stroke patients to train hand movements with less aid of a therapist, and allows objective assessment of hand function. The mechanical design allows to control the movement of five fingers individually. Force feedback is provided via a leverage mechanism, which is driven by DC motors. Additionally, tactile feedback is presented through vibration motors, attached to each fingertip. We present three different operating modes, active assisted, passive assisted and active non-assisted haptic interaction mode. The performance of the device shows that it is possible to provide feedback forces up to about 14 N for each finger, a maximum joint angle of 62°, 88° for MCP and PIP joint respectively and a settling time of 0.37 s in the passive assisted mode. Based on the characterization of the proposed device, it has a potential to be utilized in hand rehabilitation in terms of regaining both sensory and motor function.