Research on Indoor and Outdoor Navigation Technology Based on the Combination of Differential GNSS and Lidar SLAM

In order to meet the needs of the complex and changeable working environment of the indoor and outdoor navigation of the working route distribution such as AGV and mobile robot, the integrated navigation method of differential GNSS and Lidar SLAM is proposed. Firstly, the accuracy of positioning and navigation information is improved by using the differential GNSS navigation system outdoors. At the same time, the stability of navigation information is improved by the combination of GNSS system and INS system. The geodetic coordinate system is transformed into the plane coordinate system by the Gauss projection method, and the position and posture information is obtained by the double antenna measurement method; The Lidar SLAM algorithm is used indoors to obtain the pose information in the Lidar plane coordinate system. Then, the two coordinate systems are respectively translated and rotated for coincidence processing to obtain the navigation pose information. Finally, according to the status of the navigation information from different sources, switching is performed at any time to ensure the reliability of indoor and outdoor navigation information. It is verified by experiments that the accuracy of the navigation position information is less than 3 cm, and the accuracy of the heading angle is less than 0.01 degree. The experimental results show that the navigation pose information has high accuracy and good robustness, and is suitable for complex and variable environments indoor and outdoor.