The Research On Intelligent Obstacle Avoidance System For Electric Wheelchair

At present,China has become a country with the largest number of elderly people in the world;coupled with the proportion of people with disabilities increasing year by year,people pay increasingly more attention to the development of wheelchair industry.Combining specific sensor technologies and man-machine interfaces with traditional wheelchairs makes the development of wheelchairs more consistent with the pace of modern life,bringing convenience to the users.This topic is mainly for the research of intelligent obstacle avoidance system of electric wheelchairs.Adding intelligent obstacle avoidance system on the basis of electric wheelchairs enables the wheelchairs to automatically manage path planning and avoid obstacles in actual operation,making improvements to the path algorithm so that intelligent obstacle avoidance wheelchairs can reach destinations safely and quickly.The intelligent obstacle avoidance wheelchairs are divided into several modules,which are master control module,ultrasonic sensor detection module,intelligent obstacle avoidance module,energy and driver module.Control of the intelligent obstacle avoidance wheelchairs is actualized via processing of the information provided by each module by the master control module.Ultrasonic sensor detection module is based on the the principle that ultrasonic sensors emit ultrasonic waves,of which the reflections are received by the acceptors when the ultrasound meets obstacles;the module can manage real-time inspection on the local environment information for intelligent obstacle avoidance wheelchairs.The obstacle avoidance module compares the distance between the intelligent obstacle avoidance wheelchair and the obstacle and the originally designed safety distance;when the distance is less than the minimum safety distance,the wheelchair will take automatic obstacle avoidance measures.The driver module is adopted with the DC brushless motor.After receiving the corresponding instruction from the user,the master control module transfers the instruction to the motor driver module to complete the corresponding action andrealize the movement control of the wheelchair.Path planning is combined with overall path planning and local path planning.The overall path planning is a comprehensive path planning based on the GPS positioning system and the environment map information from the GPS positioning point to the destination,and the optimal path is to be searched acquired with algorithm A* under overall path planning.In the optimal path,there will inevitably be obstacles;at this time,ultrasonic sensor ought to be utilized to detect the obstacle information under the local path so that local path planning can be made and local path planning algorithm can be improved to actualize real-time obstacle avoidance.Utilization of the completeness of overall path planning and the real-time performance of local path planning can make the path planning of intelligent obstacle avoidance wheelchairs more secure and reliable.