Mobile Robot Autonomous Environment Exploration In Dynamic Indoor Environments

In the mobile robot field,autonomous environment exploration ability is one of the important criteria to measure whether mobile robot have autonomous capability.In order to solve this problem,the research focus of this paper includes simultaneous localization and mapping,environmental exploration method and path planning.Simultaneous localization and mapping provides location and map information,environment exploration method finds the best exploration point according to the map,path planning direct the robot to reach the best exploration point.In order to obtain location and map information,two typical SLAM algorithm that Rao-Blackwellized particle filtering and Cartographer are analyzed.Because the Cartographer algorithm has efficient closed-loop optimization,better accuracy of location and mapping,this algorithm is used to provide location and map information for the autonomous environment exploration.This paper proposes an efficient path planning algorithm.The algorithm includes multi-layer environment model,global path planning and local path planning.The multi-layer environment model is updated based on the grid map built by SLAM and laser data,and provides environmental information for path planning.In order to compute global path planning in real time and obtain the optimal Euclidean distance path,this paper proposes a global path planning algorithm based on Fast marching algorithm and gradient method.In order to ensure that local path planning follow the global path better,this paper proposes a improved dynamic window method.This algorithm constructs wavefront graph using wave-front algorithm,and improves evaluation function of dynamic window method by wavefront graph.Aiming at solving the problem that traditional frontier detection methods extracted invalid frontiers from grid map,this paper proposed exploration environment model based on the grid map.Besides traditional frontier exploration method only consider recently frontier as the next best exploration point,this paper proposed exploration method based on frontier evaluation.this method introduced the information gain of frontier and the cost of arrived at frontier to the evaluation function for improving exploration efficiency.Finally,this paper verifies the effectiveness of autonomous environment exploration by doing experiments in indoor scenario of DUT.The hardware platform is a pioneer3 with 2d laser,the software framework is ROS(Robot Operating System).