Contents 1 Introduction
With the aging of the global population and the acceleration of the pace of life, as well as the impact of factors such as poor eating habits and the environment, rapid increase in limb movement disorders caused by stroke, spinal cord injury, brain trauma and etc [1]-[3]. After the patients with various types of limb movement disorders are stable, the patients need a long time to undergo rehabilitation treatment, so that the damaged nerves can gradually recover. Clinical research shows that the sooner the functional training is performed after the onset of illness, the more it can reduce the sequelae, reduce the disability rate, and return the patient to society [4]-[7]. Rehabilitation training robots can replace rehabilitation therapists to achieve accurate, stable, and continuous rehabilitation training during the rehabilitation process of patients with limb movement disorders [8]-[11]. With the improvement of technology, more and more servo drive systems are used in various rehabilitation robots. However, due to insufficient muscle strength of the patient's limbs during the use process, and the field environment and other factors randomly interfere with the feedback speed signal and the feedback torque signal in the control system, thereby affecting the control accuracy of the motion control system. In order to obtain accurate feedback speed signals and obtain better control results, it is particularly important to improve the dynamic performance of the motion control system.
