Three-dimensional topographic mapping system and mapping method

A three-dimensional topographic mapping system, comprising:

• a floating platform, wherein the floating platform is located in the stratosphere above a predetermined ground area that is to be mapped;
• a detection apparatus, arranged on the floating platform and configured to map the predetermined ground area according to mapping instruction information transmitted by a ground apparatus, and return mapping data to the ground apparatus;
• and
• the ground apparatus, configured to transmit the mapping instruction information to the detection apparatus according to a predetermined mapping task, and process the mapping data returned by the detection apparatus, to obtain three-dimensional digital elevation model (DEM) data of the predetermined ground area, wherein the detection apparatus comprises:
• a detection angle adjustment apparatus, connected to a lidar detector and configured to control, according to detection time information and detection angle information that are calculated by a controller, the lidar detector to point to a start detection point of the predetermined ground area, and point to all target detection points of the predetermined ground area according to a predetermined trajectory;
• the lidar detector, configured to transmit, according to the detection time information calculated by the controller, a first laser detection signal to all the target detection points of the predetermined ground area, and receive a second laser detection signal reflected by the target detection point;
• and
• the controller, connected to the detection angle adjustment apparatus and the lidar detector and configured to calculate the detection time information and the detection angle information according to the mapping instruction information, form the mapping data by using the first laser detection signal and the second laser detection signal, and return the mapping data to the ground apparatus, wherein wherein the detection apparatus further comprises:
• a wind speed measurement apparatus, connected to the controller and configured to collect wind speed information of a location at which the lidar detector is located, wherein the controller is further configured to correct the three-dimensional location coordinates of the lidar detector according to the wind speed information.