Research On Path Planning Of Mobile Robot Based On ROS Platform

With the development of society and the progress of science and technology,mobile robots gradually come into people's lives,as the key technology of mobile robots,path planning has been widely studied and applied.According to the mastery of environmental information,path planning technology can be divided into global path planning under the condition of known overall environmental information and local path planning under the condition of incomplete or unknown environmental information.Due to the complexity of mobile robot environment,a single path planning algorithm can not meet the requirements of path safety,path optimization and stable operation.This paper aims to construct a hybrid path planning method considering these three factors,so as to improve the working efficiency of mobile robot.Therefore,this paper studies the global and local path planning algorithms in indoor environment,the A *algorithm is used to find the global optimal path under the global environment information,and then the dynamic window approach(DWA)is used to optimize the local path.Finally,the two algorithms are organically integrated to construct a hybrid path planning method.The main research contents are as follows:Firstly,facing the known indoor environment,A * algorithm is used for global path planning.Aiming at the problems of multiple break points,unsmooth paths and some paths close to obstacles in the path planning of A * algorithm,an obstacle risk assessment model is constructed in the planning process,which can limit the number of obstacles around the feasible path in the environmental map and improve the safety of the path,at the same time,by eliminating the redundant nodes in the path,the effective node sequence is constructed to smooth the planned path,which effectively reduces the path length.Secondly,DWA algorithm is used for local path planning.In order to improve the problem that the mobile robot is not smooth or passes the goal position when approaching the goal position,the distance parameter between the end of the trajectory and the goal position is lead into the trajectory assessment function of DWA algorithm to improve the velocity control effect of the mobile robot in the process of approaching the goal position.At the same time,in order to improve the traditional algorithm without considering the shape of the mobile robot,the environmental obstacles are inflated,and the simulation trajectory of the algorithm is divided by the safe state and the emergency state,so as to improve the safety performance of the local planning of the mobile robot.Finally,based on the improved A * algorithm and DWA algorithm,the hybrid path planning method is constructed.Firstly,A * algorithm is used for global path planning to obtain the effective node information in the path,and it is used as the local target point of DWA algorithm for local path planning to realize the hybrid path planning.Through the simulation of MATLAB platform and indoor environment test of Turtlebot3 mobile robot platform based on ROS,the optimized A * algorithm,DWA algorithm and hybrid path planning method are compared.The experimental results show that,compared with the single A * algorithm or DWA algorithm,the hybrid path planning method constructed in this paper can improve the path safety,path optimization and dynamic obstacle avoidance of mobile robot in the actual driving process.