Walking Assistive Robotic Suit And Its Effect Evaluation Method

Aging in China comes into conflict with requirement of companionship as well as care and lack of human as well as financial resources to meet their needs.To improve self-care ability of the elderly,prolong the independent walking time and delaye functional decline of lower limbs,there appears more and more production for disable and the elderly.What’s more,it becomes a research hotpot of wearable walking assistance device.This research aims at the elderly people who are unable to walk for a long time due to the decrease of quadriceps muscle strength due to aging,and the body structure of a walking assistive device is designed to perform kinematics and dynamics analysis.The sensory system proposes a gait evaluation parameter that is independent of the speed and objectively evaluates the assisting performance of this assistive device.Firstly,the physiological characteristics and the movement mechanism of human lower limb joints were analyzed.According to the characteristics of target population,the degree of freedom of lower limb joints were selected as well as the driving method.The mechanical structure of walking assistive device was capable of driving the hip joint was designed and the man-robot interaction position was rationally arranged.Then a simplified model of the body structure of the device is established.Considering the single-input multi-output characteristics of the booster device,the kinematic relationship between the real-time position change amount of motor and leg lift angle is established.In combination with the rigid body dynamics modeling method,reference is made to healthy young adults and healthy elderly people.The hip movements of the elderly and those with a history of falls have established a dynamic model between the real-time assist torque and human hip joint torque as a control basis for the assist device.Next,according to the characteristics of the flexible structure of the walking assistance,a perceptual system is built.Joint angle information is collected,real-time angle fitting is implemented based on the Levenberg-Marquardt algorithm,and the latest gait prediction is implemented.Force sensor is used to collect human-robot interaction force Information.Based on the latest gait prediction results and human-robot interaction force information,PD control is adopted to achieve walking assistance.Finally,an experimental system for the flexible lower limb assist device was established and a walking assistance experiment was conducted.In order to objectively evaluate gait improvement after the wearing this walking assistive device,a gait assessment parameter was studied.The experimental results show that the gait prediction results can provide a basis for gait boost control.The proposed control scheme has less target force following error and the gait evaluation parameter is feasible.When evaluating this walking assistive device through the gait evaluation parameter,it shows that the device has good effect on walking assistance.