Design And Research Of Multifunctional Stair-climbing Wheelchair

With the acceleration of China’s modernization process,people’s material lives have been significantly improved.At the same time,with the intensification of the aging population and the growing number of disabled people,how to improve their life is a problem we must face.Although the old-age helper and disability service robots have made certain progress,ordinary wheelchairs can’t be applied to ravines,steps and staircases.In view of the above problems,a multifunctional stair wheelchair with simple structure and easy manipulation is designed in this paper.It can realize three functions: flat walking,standing walking and climbing stair through the transformation of planetary gear system.The rationality of the virtual prototype design is verified by the co-simulation technology.Based on this,a physical prototype is assembled.What’s more,typical experiments are designed and verified according to the wheelchair working mode.The main jobs of this paper are shown as follows.1.Design of the stair climbing structure.Through comparing the advantages and disadvantages of the star wheel,crawler,leg and compound climbing structures,the paper determines the plan of the climbing structure,and designs a multifunctional stair climbing wheelchair based on planetary gear train.The process of wheelchair crossing barrier is analyzed and dynamic model is established.At the same time,according to the working mode of wheelchair,the motor is selected and the mathematical model of the motor is established.2.Co-simulation of virtual prototyping.A fuzzy self-tuning PID controller is designed,and a closed-loop motor control system is built in Simulink.The 3D model is imported into ADAMS,and co-simulation is performed by MATLAB and ADAMS to verify the rationality of the designed mechanical structure and control algorithm.3.Design of wheelchair control system.The design of the control system main includes hardware circuit and software program.Hardware circuit mainly includes the design of the STM32 minimum system,motor drive circuit,the peripheral detection circuit,and feedback circuit.The software programming is based on the modular design idea of wheelchair function,and a mobile phone control software is designed to facilitate the wheelchair debugging.Finally,the paper completes the debugging of hardware and software for stair climbing wheelchair control system.4.Construction of physical prototype and verification of typical experiments.The designed wheelchairs is processed and assembled to build physical prototypes.According to the wheelchair working mode,the paper designs the experiment of walking,turning and stair climbing to test the performance of the whole machine.After comparing the experimental data obtained with simulation experiments,the paper summarizes and analyzes the experimental results and error sources.Combined with the digital design of the virtual prototype and the physical prototype test,the mechanical structure and control system of the stair climbing wheelchair are designed and analyzed.The paper has reference for the design and optimization of similar products.Experimental results show that the designed climbing wheelchair has strong adaptability and high stability.