EasonDrone_Mapping

A ROS package for mapping with LiDAR and D435i.

RealSense T265 is a tracking camera that is designed to be more optimal for Visual Odometry and SLAM (wider field of view and not using infrared light). It can do SLAM onboard as well as loop closure. However, this camera is not able to return RGB images (since it does not have a RGB camera onboard) and the depth returned is not as good as the D400 series (and can be a little trickier to get).

Using both a RealSense D435i sensor and a RealSense T265 sensor can provide both the maps and the better quality visual odometry for developing a full SLAM system. The D435i used for the mapping, and the T265 for the tracking.

Compilation

catkin_make install --source Reconstruction/EasonDrone_Mapping --build Reconstruction/EasonDrone_Mapping/build

octomap

建立地图

In real world,

roslaunch easondrone_mapping experiment.launch

In simulator,

roslaunch easondrone_mapping simulation.launch

保存地图

You are trying to invoke octomap_saver as an argument to the octomap_server node. However, octomap_saver is a node of its own, so you only have to start it from a separate terminal while octomap_server is running. Check the documentation at http://wiki.ros.org/octomap_server#octomap_saver

控制无人机完成建图后，用以下指令保存.bt（相较于.ot体积更小）格式的地图文件，默认保存到~/下，

rosrun octomap_server octomap_saver -f map.bt

参考：

• https://octomap.github.io/octomap/doc
• ⭐️ https://wiki.ros.org/octomap
• ⭐️ https://github.com/OctoMap/octomap_mapping/blob/kinetic-devel/octomap_server/src/OctomapServer.cpp
• ⭐️ https://groups.google.com/g/octomap/c/ZyfNzcuGlY0?pli=1

查看地图

方法1：rviz

一种方法是在rviz中查看，

rosrun rviz rviz
rosrun octomap_server octomap_server_node map.bt

添加OccupancyGrid，话题选择/octomap_binary，

参考：

• 在ROS中将点云（PointCloud2）生成Octomap，rviz可视化显示
• ⭐️ octomap in rviz and occupancy grids in 3D maps

方法2：octovis

也可以借助octovis工具查看，

octovis map.bt

加载地图

参考：

• ⭐ how to use octomap_server?
• ⭐ OctoMap/octomap_mapping

Cartographer

Cartographer is a system that provides real-time simultaneous localization and mapping (SLAM) in 2D and 3D across multiple platforms and sensor configurations.

开始建图

roslaunch cartographer_ros ~/cartographer_ws/src/cartographer_ros/cartographer_ros/launch/demo_backpack_3d.launch

结束建图

rosservice call /finish_trajectory 0
rosservice call /write_state "{filename: '~/map.pbstream'}"

参考：

• ⭐手把手教你编译cartographer
• Cartographer ROS Integration
• cartographer-project/cartographer_ros

Release Note

• v2.1.2: import message_filters::sync_policies::ApproximateTime for merge
• v2.1.1: publish pose
• v2.1.0: merge PointCloud2 from several sources, with frame_id = "base_link"

Acknowledgement

Thanks to following packages:

• global_planning