The recordings were performed in dual-return mode of a Livox Tele-15 LiDAR. From the device manual, the continuously rotating lasers capture point cloud from the scene. One could imagine how a few seconds of interruption in data recording could result in a sequence of missing points. This is happening between frames in the Livox Tele-15. This phenomenon is illustrated in the following images.
Usual case
Example of missing points
The points between consecutive frames is continuous.
The points between consecutive frames is discontinuous.
Naturally this is also reflected in the timestamp.
Each value in the above plot represents the difference in time (time-gap) between the last point of a specific frame and the first point of the subsequent frame. The plot displays such time-gaps between consecutive 100 frames. Three sets of time-gaps can be observed from the plot.
The lowest set is the most frequent being the median with a value close to ~4 microseconds (4.35e-06 seconds). This is also the value between any two consecutive points in the point cloud. This means in this case no points are lost.
The middle set is least frequent and is closer to a value of ~200 microseconds (0.0002 seconds): This means that a certain number of points is lost during this jump. Calculation of the average number of points lost correspond to 1 data package lost (from Livox-SDK-Communication Documentation, approximately 48 samples/points are lost)
The highest set is least frequent and is closer to a value of ~400 microseconds (0.0004 seconds): This means that a more number of points is lost during this jump. Calculation of the average number of points lost correspond to 2 data packages lost (from Livox-SDK-Communication Documentation, approximately 96 samples/points are lost)
It is important to observe that the time-gaps become double during recording in single return mode.
What could be the cause for this problem? Is there a solution for not losing these points/data packages during the recording?
Loss of points/data packages during recordings
The recordings were performed in dual-return mode of a Livox Tele-15 LiDAR. From the device manual, the continuously rotating lasers capture point cloud from the scene. One could imagine how a few seconds of interruption in data recording could result in a sequence of missing points. This is happening between frames in the Livox Tele-15. This phenomenon is illustrated in the following images.
The points between consecutive frames is continuous.
The points between consecutive frames is discontinuous.
Naturally this is also reflected in the timestamp.
Each value in the above plot represents the difference in time (time-gap) between the last point of a specific frame and the first point of the subsequent frame. The plot displays such time-gaps between consecutive 100 frames. Three sets of time-gaps can be observed from the plot.
It is important to observe that the time-gaps become double during recording in single return mode.
What could be the cause for this problem? Is there a solution for not losing these points/data packages during the recording?