Design And Research Of Lower Limb Rehabilitation Training Robot

In recent years,with the increasing intensification of China's aging,the number of people with lower limb movement disorders caused by diseases or other accidents is increasing.Rehabilitation robots have been widely used as an assistance training device.But now the movement of the lower limb rehabilitation robot is mostly rigid,and the patient feel uncomfortable and unnatural after use.The impedance in active training is often added from the control level,which is more tedious to achieve and the impedance in training is kept constant.In this article,a flexible module at the robot leg of the lower limb rehabilitation training robot was added to provide the damping of the nonlinear changes at the joint during active training,and increases the flexibility at the joint during passive training to satisfy the patient's need for comfort and naturalness.Finally,a rehabilitation measurement and evaluation system was designed.According to the evaluation results,the most similar training program was selected for the patients.At first,the overall design of the lower limb rehabilitation robot was designed,then its components such as bionic legs module and variable damping module were designed.The degree-freedom and the length parameters of the bionic legs and the motion-range of the joints was determined by referring to the relevant medical literature,then a D-H coordinate system was established to perform positive kinematics analysis to verify whether there is coupling in the movement;In order to cover more patient populations,the length of the corresponding big and small legs of the bionic leg module can be adjusted,and the movement range of the bionic leg joints is designed with safety limits to avoid exceeding the normal joint range of the human body and suffering a secondary injury.Aiming at the shortcoming of the lack of flexibility at the joints in passive training of lower limb rehabilitation robots,based on the principle of hydraulic damping,a variable damper was designed,and a flexible module was designed by combining variable damper and elastic element to increase the flexibility of the joint.Then,the dynamic analysis of the two installation forms of the flexible module is carried out,and the torque stability time of the flexible module is selected to be within 0.5s.At the same time,based on the variable damping function of the variable damper to realize that the value of the impedance force in the active training is non-linearly changed,and the "aquatic therapy-like" training method is realized.In order to make the rehabilitation measurement results more scientific and efficient,the patient's own healthy limbs are used as the reference,motion range(ROM),muscle strength(F),and gait curve(G)are selected as the evaluating indicators..Firstly,the weight of the evaluation index is determined by AHP analytic method;Secondly,the comprehensive evaluation system of the three evaluating indicators is established by FCE fuzzy evaluation method which comprehensively reflects the rehabilitation status of the patient;Finally,in order to scientifically formulate the rehabilitation training program for the patient,CBR case reasoning is adopted to provide patients with targeted rehabilitation training programs,the computer selects the case with the largest similarity based on the analysis of existing cases.According to the relevant adjustment algorithm of the lowest similarity standard,the largest similar case is directly called or modified and reused.