Design of an Active and Passive Control System of Hand Exoskeleton for Rehabilitation

Abstract

Aiming at stroke patients’ hand rehabilitation training, we present a hand exoskeleton with both active and passive control modes for neural rehabilitation. The exoskeleton control system is designed as a human–robot interaction control system based on field-programmable gate array (FPGA) and Android mobile terminal with good portability and openness. Passive rehabilitation pattern based on proportional derivative (PD) inverse dynamic control method and active rehabilitation pattern based on impedance method, are established respectively. By the comparison of the threshold value and the force on the fingertip of the exoskeleton from the sensor, the automatic switch between active and passive rehabilitation mode is accomplished. The hand model is built in Android environment that can synchronize the movement of the hand. It can also induce patients to participate in rehabilitation training actively. To verify the proposed control approach, we set up and conduct an experiment to do the passive rehabilitation mode, active rehabilitation mode, and active plus passive mode experimental researches. The experiment results effectively verify the feasibility of the exoskeleton system fulfilling the proposed control strategy.

Preliminary Results in Testing of a Novel Asymmetric Underactuated Robotic Hand Exoskeleton for Motor Impairment Rehabilitation

“…One can mention, among advantages, that the proposed design offers a specified center of rotation for the MPC joint, in contrast to the solutions proposed by Chiri et al [6]. It can be said that the current design can offer a natural movement of the wearer's hand, compared to other fully-actuated exoskeleton models, such as those presented in Zhang et al [55], where each joint is independently actuated, thus involving a highly complicated control algorithm, due to the fact that the exoskeleton does not adapt very well to different anthropological dimensions and behaviors. On the other hand, one can mention as disadvantages the lack of certainty for each of the joints' positions, which obviously is a negative characteristic.…”

“…Therefore, this device has the ability to present easily changeable components based on the person's anthropological measurements. Another advantage resides in a more compact design for DIP and PIP joints, compared to other underactuated models (as well as some fully-actuated models) such as those of Shields et al [35], Wege et al [36], and Zhang et al [55]. One can mention, among advantages, that the proposed design offers a specified center of rotation for the MPC joint, in contrast to the solutions proposed by Chiri et al [6].…”

Design and Development of Continuous Passive Motion (CPM) for Fingers and Wrist Grounded-Exoskeleton Rehabilitation System

“…In [30], the authors designed a wearable exoskeleton mechatronics system based on active and passive control approaches for single-finger rehabilitation. The proposed device is operated by a field-programmable gate array (FPGA) and controlled through an Android smartphone application.…”

Integral Fuzzy Sliding Mode Impedance Control of an Upper Extremity Rehabilitation Robot Using Time Delay Estimation

“…In practical implementation, the control strategies applied in rehabilitation robots directly determine the performance of robot-assisted rehabilitation training [18]. Currently, the existing rehabilitation control schemes can be classified into two types according to the participation degree of patients, i.e., the passive training control strategies [19]- [21] for the patients at the acute period to passively conduct repetitive movement tasks along predefined trajectory, and the cooperative training control strategies [22]- [26] for the patients at the recovery period to be actively engaged in the therapy training program. In [27], a passive training control approach combined with neuron proportion-integral and feedforward compensation control was developed to reduce the trajectory tracking error of a pneumatic muscles-driven rehabilitation robot.…”