TSPS MAR 2025 FINAL REV - Flipbook - Page 16
TECHNOLOGY
TECH TALK
Comparison Between the DJI L2
LiDAR and the PLS RIEGL Mini 3 Lite
LiDAR on the Same Project, and a
overview of our results of Combining
Aerial and Terrestrial Scan Data
BY: Robert L. Young - RPLS, Alexis Cardona López
he original plan was to compare the methods of data
collection from both terrestrial and aerial scanning, followed by more ef昀椀cient data extraction for CAD.
If your company has ventured into the world of drone LiDAR
and terrestrial scanning, you’ve likely had to do extensive research and self-learning, as most of us have. In 2015, we entered
the drone world, just like many small companies, through DJI.
This article is not intended to promote the DJI products, the
Harris H6E drone, or the PLS (Phoenix Lidar Systems) Riegl Mini
3, but to compare the results obtained from both sensors on the
same project for learning purposes.
T
SITE:
Texas Amphitheater – Glen Rose, Texas – August 2024
PURPOSE OF SURVEY:
A1 - GCP Elevation Comparison (RIGHT)
In three tables compare the elevation differences in Ground
Control Points (GCPs). Elevation for each point was obtained
by creating a surface from the XML 昀椀les generated from each
昀氀ight. Points were then created in CAD at the exact location
of each GCP, using the elevation from the relevant surface.
In the tables, numbers in red indicate differences greater
than 0.2, while values in blue represent the average of all
differences. My observations indicate that there was no signi昀椀cant difference between the 昀椀rst and second 昀氀ights with
the RIEGL system.
The LidarMill comparison report shows better accuracy in
elevation differences with the GCPs, with an error of 0.0568.
However, this is an internally generated report by the processing system.
On the other hand, the DJI comparison report presents an
acceptable average elevation. However, it’s observed that GCP
8 has a signi昀椀cant difference of 0.76218, and GCPs 5 and 11
show differences greater than 0.40.
B1 - Surface Creation and Contour Lines (BELOW)
Here the, XML 昀椀les were used to generate TINs to create surfaces and topographic contour lines. It was observed that the
RIEGL system produces less noise in the data, which aids in
the Automatic generation of break lines. In contrast, the DJI
system captures more noise, complicating the precise delineation of break lines.
RIEGL
Conduct an ALTA boundary survey.
HYPOTHESIS:
To determine the utility of combining aerial and terrestrial LiDAR
with point cloud data from the LEICA RTC360, and to assess the
potential of TopoDot and Carlson Point Clouds software for automatic or manual extraction. We also aim to identify the best use
of LiDAR sensors for our future projects.
EQUIPMENT USED:
• DJI M300 with L2 LiDAR sensor and 35mm P1 camera with 48
megapixels.
• Harris Aviation H6E drone with Riegl Mini 3 Lite LiDAR sensor.
• Carlson BRX7 for static and RTK GNSS.
• LEICA RTC 360 terrestrial laser scanner.
• DJI Terra and Virtual Surveyor for processing DJI data.
• Lidarmill for processing Riegl data.
• TopoDot within Bentley Open City.
• Cyclone REGISTER 360 Plus for processing RTC 360 data.
• Carlson CAD – AutoCAD.
1. DRONE LIDAR EQUIPMENT COMPARISON REPORT: DJI AND RIEGL
Report detailing my observations and comparisons of the data
collected using DJI and RIEGL drone systems. Below are the results of the various analyses performed.
14 THE TEXAS SURVEYOR March 2025
DJI
