Design And Realization Of The Intelligent Wheelchair Controller Based On STM32

With the continuous improvement of living standards, the intelligent wheelchair has gradually replaced the manual wheelchair, plays a more and more important role in some people’s life, who are the frail elderly or the lower limb disabled. Now, the intelligent wheelchairs on the market are various in styles, but their function is similar and the prices are too expensive. The designers of intelligent wheelchairs failed to fully consider people’s physiological and psychological differences. So it’s hard for users to choose a cheap intelligent wheelchair for themselves according to their own actual health.The research object of this paper is the intelligent wheelchair which has six wheels. There are two driving wheels in the middle of wheelchair’s chassis, before and after the driving wheels there have a pair of small driven wheel. This paper chooses STM32series microcontroller STM32F103xx as the main control chip. This paper completes the design of hardware and software of control system and achieves the expected design goal of high performance with low price. And thanks to the modular design, the user can customize different modules as well as adjust the relevant parameters according to their own needs.After studying the research of intelligent wheelchairs at home and abroad, we present the overall scheme of the control system and introduce some working principles in detail. Secondly, according to the function of the intelligent wheelchairs, we map the hardware circuit of the control system, and complete PCB board of the driving controller. The circuits of the operating module include the signal collection circuit, key and display circuit. Because of some security reasons, an emergency brake button is designed on the control panel, when users encounter an emergency situation, they can use this button to stop the wheelchair and lock the other keys on the panel. The communication wake-up circuit and motor drive circuit of driving controller are designed, and the experimental results have demonstrated that the communication wake-up circuit can wake up the power module of driving controller. The CAN communication protocol is selected as the communication protocol of the system, so the number of communication cable is reduced. And it is easy to reform and upgrade the system. Then, the overall flow chart of the system operation is designed. Software program of some main functional modules are designed and simulated. Those modules include PWM signal generation module, slow acceleration/deceleration method and CAN communication module. Finally, in full consideration of the wheelchair users’psychological demands, the attendant module is designed. This module allows caregivers set the running speed of wheelchair as same as their own normal walking speed. So caregivers can walk with the wheelchair user side by side and can communicate well with each other. Furthermore, a simple unevenness (bump/dent) detection system using a monocular camera to ensure safety of a handle type intelligent wheelchair is proposed.