User's Manual

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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 Pandar128’s Channel 5 in Block 2 as an example:
1) Vertical angle of Channel 5 is 12.165°, according to Appendix I Channel Distribution
NOTE
The accurate vertical angle is recorded in this LiDAR’s unit’s calibration file
Users can obtain the calibration file by sending the TCP command PTC_COMMAND_GET_LIDAR_CALIBRATION, as described in Section 6.2
2) Horizontal angle = current reference angle of the rotor + horizontal angle offset
▪ Define clockwise in the top view as the horizontal angles’ positive direction
▪ Current reference angle of the rotor is the Azimuth field of Block 2
▪
Horizontal angle offset of Channel 5 is 1.093°, according to Appendix I Channel Distribution
NOTE
The accurate horizontal angle is recorded in this LiDAR’s unit’s calibration file
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