Structural Design Of Flexible Lower Limb Rehabilitation Robot

Rehabilitation of patients with lower limb function degradation and stroke has become a research hotspot in modern rehabilitation medicine and rehabilitation engineering because the severity of aging and the increase in the prevalence of stroke patients.In order to provide patients with accurate,effective and objective rehabilitation process,various countries began to develop lower limb rehabilitation robots,as a medical robot with special functions,the lower limb rehabilitation robot can assist patients in rehabilitation training and improve the efficiency and effect.In this paper,a flexible lower limb rehabilitation robot is designed for patients with lower limb motor dysfunction,focusing on structural design and control strategy.The main contents of the paper are as follows:1)Research and Analysis of Human Lower Limb Structure and Gait Characteristics.During the research process,the normal human gait motion parameters were tested based on the three-dimensional motion capture system to determine the law of lower limb motion;Determine the relationship between the gait movement and the sole pressure through the force plate to test the change of the sole pressure of the human body during the gait movement.2)The design requirements and design proposal of the flexible lower limb rehabilitation robot are proposed and the model is built.This paper proposed the design requirements of the flexible lower limb rehabilitation robot based on the structure of human lower limb and the mechanism of lower limb rehabilitation.Based on the comparison of the advantages and disadvantages of the existing lower limb rehabilitation robot,it further proposed the body mechanism design scheme of the flexible lower limb rehabilitation robot based on the imitation muscle drive device.The robot designed in this scheme has the characteristics of high bionics,good flexibility,large range of motion,and high safety.Subsequently,Solidworks was used to build a three-dimensional model of a flexible lower limb rehabilitation robot,which mainly includes a suspension weight reduction device,a lower limb training device,a muscle-like driving device and a foot pressure device.3)Theoretical analysis of devices of flexible lower limb rehabilitation robot.The analysis mainly includes the following aspects:(1)The finite element analysis of the suspended weight reduction device is carried out to determine the safety and stability of the lower limb rehabilitation robot structure.According to the static analysis,it is concluded that the structure design of the suspension device is reasonable;in the modal analysis,the inherent characteristics and weak points of the structure are found,and the direction for further structure optimization and control is found;(2)The modeling analysis of the imitation muscle drive device,through the analysis,verified the good flexibility of the imitation muscle drive device;(3)The kinematics forward and inverse solution analysis of the lower limb training device and the planning of the motion of the rigid branch,the change law of the length of the rope and the position of the rigid branch is obtained by solving;(4)Based on the dynamic analysis of the lower limb training device based on the Lagrangian method,the dynamic equation is obtained,which provides the control target for the research of the control theory.4)The realization of the control system of the flexible lower limb rehabilitation robot and the construction of the product prototype.Rehabilitation exercise based on KEIL software programming,and action verification on the product prototype,the experimental results show that the tracking performance and control accuracy of the developed lower limb rehabilitation robot prototype meet the design requirements.