Structure Design And Performance Analysis Of Semi-sharing Stair-climbing Wheelchair

The population aging phenomenon has continued to increase,while the number of aging population and physically disabled population is increasing.How to overcome the topography of the stairs to achieve the purpose of travel has become a hot spot now.At the same time,with the continuous development of mechanical automation technology and the country’s requirements for an elderly-friendly society,stair-climbing wheelchairs has become an important research direction.Summarizing the development status of wheelchairs at home and abroad,a semi-sharing stair-climbing wheelchair is proposed according to the actual needs of the society.The stair-climbing wheelchair is divided into two parts,a stair-climbing module and a flat driving module.A public climbing body in a place with many steps and terrain is placed.Users only need to carry the foldable flat driving module,and the two modules can be simply assembled before climbing to perform the climbing operation.Under the premise of meeting the basic requirements of the climbing operation,the use of climbing is greatly reduced.The economic consumption of wheelchairs in the building meets the needs of most domestic wheelchair users.Firstly,the stairs environment and climbing performance requirements is seted,and a modular design method is adopted.according to the design requirements,the climbing wheelchair is divided into two parts,the folding body and the climbing body,and the connecting parts are designed.The design schemes of climbing mechanism,drive,transmission,seat and control are respectively proposed.The 3D model of the climbing body,the folding body and the whole machine are builded respectively.Secondly,a kinematics model for driving on flat ground is established and the relationship between drive speed and flat posture is derived.Carrying out motion analysis of straight-line driving and steering driving in flat terrain,and mechanics analysis of the situation of wheelchair passing through complex terrain.The Adams software was used to conduct dynamic simulation of the climbing process,and the simulation results verified that the climbing process was relatively stable and met the requirements of safety performance and stable performance.The static stability and dynamic stability criteria of the wheelchair during the climbing process are established.Considering the influence of the wheelchair’s center of mass distribution and moment of inertia distribution,the stability analysis of the climbing process is carried out.The reasons for the slip phenomenon in the process of climbing stairs are explored,and the reasonable improvements based on the reasons are made.Finally,the value of overall deformation stress and strain diagram of the part are obtained by performing static analysis on the deformation,stress and strain of the part,which is compared with the yield strength value of the material.A static analysis model for the three key parts selected is established by Ansys Workbench.Whether the structure and materials of each part meet the requirements is verified,and the reasonable improvements to the parts that do not meet the requirements are made.