Force Analysis And Optimization Design Of The Hind Leg Of Stair-climbing Wheelchair

With the continuous progress and development of science and technology,electric wheelchair has gradually become the main means of transport for the seniors and the disabled.However,due to the continuous improvement of living standards,the people set a higher request to the quality of life.The ordinary electric wheelchair in the market has been unable to meet people's travel requirements,so climbing wheelchair came into being.Climbing wheelchair can not only works on the ground as an ordinary wheelchair,but also can climb the stairs,obstacles,and cross ditch.Climbing wheelchair greatly expanded activity boundaries of the disabled and the elderly.Considering the price of climbing wheelchair in the market is too high,this subject presented a different kind of wheel-legged wheelchair.The main research content of this paper is to analyze and optimize the wheelchair hind legs.In this paper,we first introduce the function-means tree design method and the port-based ontology design theory,and use the above two theories to design the auxiliary device of the hind legs,produce multiple design schemes,and evaluate the more reasonable scheme through the utility value analysis method and get the best design.With the help of the powerful virtual modeling and assembly function of UG software,the hybrid design method is adopted to design and assemble the parts of the floating wheel mechanism.Finally,the simulation of the trajectory of the wheelchair up and down is assisted by MATLAB.Secondly,the movement state of the wheelchair is analyzed,and the movement state of the hind legs is divided into no-load state and working state.According to the principle of Darren Bell,the two kinds of motion states of the hind legs of the climbing wheelchair are analyzed by the dynamic-static method.The change rule of each pivot force is determined by simulation,and the force needed to be optimized is determined.Finally,based on the genetic algorithm of MATLAB,the force of hind legs and the performance of the five-bar mechanism are used to optimize the hind leg length and get the optimal solution.The results show that the optimized hind legs are improved and the exercise performance is improved obviously.