Research On Autonomous Navigation Control Of Intelligent Wheelchair

At present, the global population aging process is accelerating. at the same time,disabled has also increased due to various natural disasters, accidents, wars and diseases.As a typical representative of HelpAge disabled service robot, intelligent wheelchair is asuperior performance means of transport for the elderly and the disabled. Theautonomous navigation technology of intelligent wheelchair is particularly important asmost users with reduced mobility. Therefore, this paper presents autonomous navigationtechnology of intelligent wheelchair in the indoor environment.First, models are established which will be referenced in the autonomousnavigation technology of the intelligent wheelchair, include wheelchair ontology model,coordinate system model, wheelchair kinematics model and environmental systemsmodels, which provide the basis for subsequent algorithm research. Location is theprimary issues to be addressed for autonomous navigation of the intelligent wheelchair.This paper presents two positioning methods by ultrasonic sensor array and deadreckoning to the features of indoor environment, after analysising the characteristics ofdifferent positioning methods. Then the improved schemes are proposed to thedeficiencies of both methods, and the Kalman filtering is used to fuse the twopositioning methods. Simulation results show that the positioning effect of this approachis much better.The A*algorithm is used to achieve the global path planning on the basis of theindoor environment map established, after comparing different path planning methods.As to the intelligent wheelchair may encounter obstacles in the process of moving, theArtificial Potential Field is used to achieve Local Path Planning. Wheelchairs need totrack the global path after planning by PID control method.In the last part, the autonomous navigation control system of the intelligentwheelchair is designed by modular, which includes control module, driver module,perception module and interactive modules. Then, the hardware circuit and the controlsoftware with the corresponding of different modules are designed.