| At present,mobile robots are more and more widely used in various fields.Positioning,mapping and navigation in unknown environments are the hot topics of mobile robot research.This topic takes indoor mobile robots as the research object,studies and improves the problems of low mapping accuracy and poor navigation path planning trajectory of mobile robots in indoor environment,improves the mapping accuracy of mobile robots in indoor environment,the speed of global path planning and the smoothness of path,and carries out simulation and comparison based on the robot operating system ROS platform and experimental tests on remote control robots,The specific research contents are as follows:1)According to the requirements of robot indoor navigation,the mobile robot navigation system framework,the robot hardware module and the communication mode of each module are designed.By analyzing the motion law of the robot,the transformation mode of the robot coordinate system and the robot motion model used are described.Compare the types of robot maps,select grid map to build the map model,and introduce the principle of grid map construction.By analyzing the lidar sensor,the single-line lidar based on the triangulation method is selected.Aiming at the distortion problem of the lidar in the process of movement,the IMU and odometer data are used for synchronous time correction to improve the accuracy of the lidar data.2)The type and working principle of traditional laser SLAM are analyzed.Aiming at the problem that the RBPF-SLAM algorithm can not provide accurate map for robot navigation due to the accumulated error of the odometer caused by the friction between the environment and the robot’s own motion,the proposed function input to improve the RBPF-SLAM algorithm is proposed,and the position and attitude difference of the laser radar at the adjacent time is used to replace the odometer data,So as to improve the accuracy of drawing.In the ROS system,the improved algorithm has more advantages than other algorithms in terms of overall mapping effect and detail accuracy through comparison with the common laser SLAM algorithm simulation and experimental test.3)After the map is built by laser SLAM,navigation is carried out on the map.Global path planning and local path planning are the key technologies of navigation.In the part of local path planning,the DWA algorithm is selected.The DWA algorithm can achieve local obstacle avoidance in the process of robot navigation and avoid robot collision with obstacles.In the part of global path planning,by analyzing the types and principles of traditional algorithms,and aiming at the problem that the path path path of BI-RRT algorithm is tortuous,which affects the robot to reach the target point smoothly,an improved BI-RRT algorithm is proposed to improve the speed and smoothness of path planning by adding target offset sampling and optimal node selection.The effectiveness and practicability of the improved algorithm are verified by comparison with the RRT algorithm and BI-RRT algorithm through simulation and experimental tests. |
