Research On Two Dimensional Localization Of Mobile Robot Based On UWB And Lidar In Indoor Environment

Localization technology is the basis and prerequisite for robot navigation and path planning.High-precision indoor localization technology are getting more and more attention as there is a rising need for indoor location-based services,which has important theoretical significance and engineering application value.The main work of thesis is as follows:First,this thesis studies the method of using linear fitting to correct the ranging error aiming at the problem that the TOA based location method in UWB location will produce systematic error due to environmental.A method of NLOS error judgment and correction based on Kalman filter is proposed aiming at the localization error when the robot is in motion.This method can effectively eliminate outliers and suppress NLOS error.Secondly,the localization method based on lidar is studied.Aiming at the problem that the refresh rate of single lidar positioning is slow and the matching error is easy to occur,the odometer lidar fusion positioning method based on particle filter framework is studied.Compared with the single lidar localization method based on laser odometer,the odometer lidar fusion positioning method has better positioning effect.Thirdly,aiming at the problem of error accumulation in odometer lidar fusion localization algorithm,a odometer lidar fusion positioning method based on UWB correction is proposed.The algorithm uses UWB observations to correct the odometer lidar fusion results,and effectively eliminates the cumulative error.Then,aiming at the problem of robot kidnapping,based on the odometer lidar fusion localization method corrected by UWB,a method of robot kidnapping recovery is proposed.This method can effectively judge whether the robot has been kidnapped or not and recover the location after kidnapping,which has a certain practical significance.Finally,a robot platform is built to verify the proposed method.The description method of world coordinate system and each sub coordinate system is established,and the transformation relationship between each coordinate system is established.The evaluation index of localization performance is given.The scheme of robot control and data exchange is realized under the embedded platform and ROS system.The upper computer software for monitoring and data acquisition is written by using QT tool,and the experiment is designed to verify the experimental method proposed in this paper.