msg types of topics
rostopic type /gps/fix sensor_msgs/NavSatFix
rostopic type /gps/rtkfix nav_msgs/Odometry
rostopic type /gps/time sensor_msgs/TimeReference
rostopic type /radar/points sensor_msgs/PointCloud2
rostopic type /radar/range sensor_msgs/Range
rostopic type /radar/tracks radar_driver/RadarTracks
detail of message
This message holds a collection of N-dimensional points, which may contain additional information such as normals, intensity, etc. The point data is stored as a binary blob, its layout described by the contents of the "fields" array.
The point cloud data may be organized 2d (image-like) or 1d (unordered). Point clouds organized as 2d images may be produced by camera depth sensors such as stereo or time-of-flight.