Local Path Planning And Obstacle Avoidance Without Blind Zone For Mobile Robots

With the continuous development of intelligent and autonomous mobile robots,autonomous obstacle avoidance and path planning are hot issues in current mobile robot research.To tackle with the problems that now available ultrasonic array obstacle avoidance detection exsisting blind zones,and the traditional fuzzy control path planning algorithm having complex rules,complicated fuzzy deconvolution,and poor parameter strain,this paper designs a novel ultrasonic array obstacle avoidance system and proposes an improved fuzzy control-based P/N local path planning algorithm.First,a new ultrasonic obstacle avoidance system is proposed in this paper for the purpose of avoiding the blind area in mobile robot‘s detection due to the narrow beam angle of the ultrasonic sensor.The system uses six ultrasonic sensors to build a specially designed ultrasonic array to locate the obstacles in front and two sides,ensuring the safety of robots.Meanwhile,the obstacle avoidance algorithm based on dichotomy makes that the mobile robot can select the best path and avoid newly appeared moving obstacles.The experiment with this obstacle avoidance control system shows that the robot can detect the surroundings without any blind area in the unknown environment,and can choose the best obstacle avoidance path instantly according to the random conditions,preventing the misjudgments and secondary obstacle avoidance.Second,this paper proposes a P/N local path planning algorithm with improved fuzzy control in order to improve that the traditional fuzzy control algorithm has complex control rules,cumbersome defuzzification and poor parameter strain.Introducing positive rules to make the robot moves toward the target point,and compensating the rules weight to enhance the strain of parameters;Introducing negative rules to make the robot avoid obstacles,and binarizing the rules to reduce the complexity of the fuzzy system;using path decision formula fusion positive and negative rules enable precise output without defuzzification so that realizing robot local path planning.The results of two sets of matlab simulation experiments show the improved fuzzy control P/N local path planning algorithm further optimizes the path and makes the trajectory smoother and shorter.Finally,in order to further verify the effectiveness of the path planning algorithm in practical application,this paper builds a joint simulation experiment platform based on Simulink and ROS and simulates the indoor path planning experiment of the robot.A high fidelity environment model with physical engine and a mobile robot model are constructed based on the Gazebo software under ROS,and the ultrasonic array detection model is loaded on the robot;and the path planning and obstacle avoidance control algorithm are completed under Simulink.The experimental results show that the improved fuzzy control based P/N local path planning algorithm combined with the specially designed obstacle avoidance system can better achieve the local path planning of mobile robots;The path planning algorithm is implemented in Simulink.The experimental results show that the improved fuzzy control P/N local path planning algorithm combined with the specially designed obstacle avoidance system can better achieve the local path planning of mobile robots.