Design And Research Of The Mechanical System For A Hand Rehabilitation Robot

Stroke has become one of the serious diseases which threaten human health. As we know, post-stroke patients always suffer from dysfunction of the limbs, so they need rehabilitation techniques to recover. The application of robotics and related technologies has greatly advanced the development of rehabilitation theory and clinical techniques; and rehabilitation robot is a new area in medical robots.As a branch of rehabilitation, hand rehabilitation, referring to varieties of trainings for the fingers, is a necessary supplement to arm rehabilitation. This thesis develops a hand rehabilitation robot for post-stroke patients. In this work, key issues as mechanical design, statics, kinematics, dynamics, sensing system, rehabilitation strategy, simulation and experiment are investigated.Based on the biological characteristics of the human hand, the mechanical driving system of the robot is developed, including an actuated finger exoskeleton, an adaptive dorsal metacarpal base and a rear-mounted artificial muscle. Combining a symmetrical pinion and rack with a parallel sliding mechanism, the actuated finger exoskeleton can be adapted to a variety of fingers with different lengths and thicknesses, and drives fingers to bend and extend without extruding or pulling the knuckles; with 18 DOFs (degrees of freedom), the adaptive dorsal metacarpal base can be tightly attached to the back of patients'palm; and by introducing the Bowden cable transmission, the rear-mounted artificial muscle can reduce the weight of the part on the patient's palm to reduce the burden on the patient's wrist.According to the mechanical design of the robot, statics, kinematics and dynamics of the robot are analyzed. This paper puts forward a solution to the close chain mechanism of the actuated finger exoskeleton as follows: for the main open chain (the finger), solves the forward kinematics using D-H method, the inverse kinematics by variable substitution, and the Jacobian matrix by differential transformation; for each close chain, directly gets the kinematics according to structure relationships; at last integrates above results and obtains the kinematics of a single finger and the whole hand. And the dynamic and static equations are obtained by Lagrange method and Jacobian matrix.By research on the robot's system structure as well as its training and control strategies, this paper also designs its sensing system. Integrating a series of position and force sensors into the mechanical driving system, the joint position and information of the interaction between the robot and patient can be fed back to the control system in real time.Finally, some simulations and experiments have been done. Simulation analysis includes kinematics and dynamics of an exoskeleton joint, dynamics and statics of a single finer and motor dexterity of the whole hand; while experiments include hand fitness test, typical CPM training experiment, man-machine interaction experiment and patient-cooperative rehabilitation experiment. The results demonstrate that the hand rehabilitation robot is well designed and reliably operated, and the patient-cooperative training strategy is feasible.