The Application Research Of Hand And Wrist Rehabilitation Robot

Stroke has become a serious disease with high incidence among aged people, which causes most survivors suffering from a series of hemiplegia sequelae. The hemiplegia sequelae mainly lead to hemiplegic patients' movement disorders, especially the hand. As we all know, the dysfunction of hand severely influences patients' daily life, so that we need to choose effective rehabilitation method to improve or recover movement ability. Compared with traditional physiotherapy and physiotherapists therapy, the robot-assisted therapy can provide repetitive rehabilitation treatment in a long-term and stable way. Therefore, as a kind of robot-assisted devices, finger rehabilitation robot has become a focus of domestic and foreign medical robotics field. In this paper, a novel hand and wrist rehabilitation robot is presented, which can achieve rehabilitation training of both finger and wrist.First of all, the paper analyzes the biological characteristics and rehabilitation theories of hand and wrist. Then the mechanical structure of hand and wrist robot is designed based on the medical requirements above, including finger grasping motion platform, wrist dorsiflexion and palmarflexion motion platform, forearm intorsion and extorsion motion platform, which can move separately or together with others. The most creative parts are finger grasping motion platform and torque sensor. The finger grasping motion platform can drive four fingers(except thumb) achieving grasping movement with only one drive rod through designing four different lengths of sliders to extend four fingers to same length to make the movement possible, which dramatically simplifies the mechanism. The torque sensor is designed to detect torques of positive and negative directions based on film pressure sensors located on two sides of shaft, which makes the mechanical structure of robot more compact.Secondly, according to control requirements of hand and wrist rehabilitation robot, the overall scheme is confirmed based on reliability principle of whole system and the PC104 IPC(Industrial Personal Computer)is chosen to be the core of control system of this robot. The paper also introduces the self-designed torque sensor in detail, including structure, detection principle and hardware circuit of this sensor. What's more, the paper analyzes the relationship of detection torque and output voltage and verifies the feasibility of this torque sensor.Thirdly, according to hemiplegia rehabilitation theories of hand and wrist, the control software program is written on the base of C++Builder development environment by adopting multilayer nested method. The program can not only control the robot to practice in active and passive training modes, but also feedback patients' motion data during the training process in real time, which can assist physiotherapists in evaluating patients' rehabilitation status.Finally, an experimental platform has been set up to conduct the position control experiments and the force control experiments of hand and wrist rehabilitation robot. The feasibility and reliability of this rehabilitation robot system have been verified through a series of velocity response curves, position curves and force control curves, which means that the mechanical structure has been designed reasonably and it could work stably. In a word, the novel hand and wrist rehabilitation robot designed satisfies the clinical rehabilitation requirements of stroke patients' hand and wrist.