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3.1.3 Point Cloud Data Analysis
The analysis of point cloud UDP data consists of three steps.
◼
Analyze the vertical angle, horizontal angle, and distance of a data point
Take PandarQT
’s Channel 5 in Block
2 as an example:
1) Vertical angle of Channel 5 is -43.465
°,
according to the calibration file included with each LiDAR
NOTE
Users can obtain the calibration file by sending the TCP command PTC_COMMAND_GET_LIDAR_CALIBRATION, as described in Section 6.2.1.
2) Horizontal angle = current reference angle of the rotor + horizontal angle offset
Current reference angle of the rotor is the Azimuth field of Block 2
Horizontal angle offset of Channel 5 is 7.417
°
, according to the calibration file included with each LiDAR
Define clockwise in th
e top view as the horizontal angles’ positive direction
3) Actual distance in real world millimeters = distance measurement * Distance Unit (4 mm)
Distance measurement is the Distance field of Channel 5 in Block 2
◼
Draw the data point in a polar or rectangular coordinate system
◼
Obtain the real-time point cloud data by analyzing and drawing every data point in a frame
