Robotic Techniques Used for Increasing Improvement Rate In The Rehabilitation Process Of Upper Limb Stroke Patients

The rate of stroke patients in Pakistan is increasing, resulting in the decrease mobility of the patients. The movement of upper limb stoke patient is decreased due to the weakness and loss of joint control in his upper body. To improve the coordination of movement of the upper limb stroke patients, many methods e.g. passive and active modes for improving the disrupted mobility are introduced. The objectives of this paper are to first review the studies on upper limb stroke patients and the techniques used for increasing the improvement rate through physical therapy by exoskeleton and evaluation of the performance of the patient using methods such as quantification and graphical representations so that it can be shown to the patient for his motivation to improve further. The paper introduces a mechanical design of exoskeleton with 1 degree of freedom for elbow and 2 degrees of freedom for shoulder movement for rehabilitation of joints of stoke patients. It also mentions the safety that will be taken in the process so that the exoskeleton is safe to use when it is in contact with human. The model of the exoskeleton has the characteristic of being modular and easily operable and use admittance control strategy. Control strategy of the exoskeleton is discussed to maintain the position and orientation of the device and also is able to cater the gravitational attraction which plays an important part in the movement of the actuators. The mathematical model of motion attained due to the degrees of freedom of the exoskeleton is then evaluated and the lastly areas where the future work of exoskeleton can be done are discussed