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4.4.3 Error Message: The raw data of the LiDAR point cloud is abnormal.
Possible cause: The collection time of the laser point cloud file (LDR) in the input path does not
correspond to or does not overlap with the collection time of other files, which may be caused by
mistakes in file copying.
4.4.4 Error Message: LiDAR point cloud accuracy optimization failed.
Possible cause: The flight altitude was too high, the speed was too fast, or the overlap was set too
low, resulting in insufficient overlapping points for point cloud accuracy optimization. In this case,
we recommend you increase the overlap and recollect the data, or disable "Point cloud accuracy
optimization" when you don't require high accuracy.
4.4.5 Error Message: LiDAR point cloud POS calculation failed.
Possible cause: The content of some files in the input path is incorrect or data is missing; the time
values in the IMU and RTK files (RTB, RTK, RTS, or RTL) do not overlap or match. In this case, you
should check the data. You will probably need to recollect the data.
4.4.6 Issue: Quality of point cloud model is poor, or the result has severe data loss.
(1)
Poor inertial navigation accuracy: Data collection started before the inertial navigation system
completed warmed-up, or IMU calibration not performed correctly
(2)
Poor POS accuracy: The RTK was not fixed, the RTK base station was moved, or the
coordinate systems of the self-built base station and multiple RTK base stations were
inconsistent (for example, no known coordinates were configured for D-RTK 2).
(3)
Low overlap: The collection time of the LiDAR point cloud file only partially overlaps with that
of other input files, or the side overlap was set too low. In particular, in areas with fluctuating
terrain, setting an excessively low lateral overlap can result in hollowing in the result.
(4)
No objects scanned: For example, in a flight with gimbal pitch -90°, the facades of a building
may be hollowed due to the lack of scanned objects. In a power line scan, if the drone flies
over the object only once, some power lines may be blocked by those above them at certain
angles. In an area with significant elevation differences, some objects may fall out of the
measurable range of L1.
(5)
Low cutting distance of point cloud: The point cloud cutting distance set is less than the actual
effective point cloud distance.
