Research And Implementation Of Automatic Obstacle Avoidance For Intelligent Wheelchair

With the increasing of aging population and varieties of natural and man-made disasters disabled limbs of many people.In order to improve the freedom and life quality of people that inconvenient in action.The requierment of intelligent wheelchair increasing day by day.Therefore more and more institutions dedicated to the research of intelligent wheelchair.Artificial intelligence technology is applied to electric wheelchair,making the intelligent wheelchair more intelligent, more comfortable, more human and safety.The intelligent wheelchair system consists of ultrasonic detection module, anti- turnover module, avoiding obstacle automatically module, path memory and reproduce module.Each module communicate with the main controller by CAN bus,the main controller process varieties of informations provided by each module,then control intelligent wheelchair according to the different informations.Ultrasonic detection module is designed based on the principle of ultrasonic encountering obstacle produce echo,this module is used to provide environment informations of the intelligent wheelchair,providing outside environmental information for automatic avoidance module.Anti-turnover module install inclined angle sensor on the intelligent wheelchair,to determine whether there is danger of overturn for intelligent wheelchair by angle information that provided by inclined angle sensor,this is a safety guarantee measure for the intelligent wheelchair.Automatic obstacle avoidance module on the basis of obstacle detection by ultrasonic detection module, use the encoder data processing, the theory of finite state machine and the automatic obstacle avoidance algorithm to control intelligent wheelchair movement state,realizing the function of automatic obstacle avoidance.Path memory and reproduce module use the local information feedbacked by encoder to record the intelligent wheelchair location of every moment.Then use these stored path can return in original path in emergency case.When there isn’t only one return path,theintelligent wheelchair can use the algorithm of Dijkstra to select the shortest path,saving time and effort.This intelligent wheelchair system adds several modules on the ordinary electric wheelchair,intelligentizing the ordinary electric wheelchair.Now each module of the intelligent wheelchair system is tested,The test results show that the intelligent wheelchair system has basically realized the obstacle detection, automatic obstacle avoidance, path memory and reproduction and so on.