YellowScan Surveyor Ultra 3 and DJI Zenmuse L2 represent the latest LiDAR models from manufacturers of LiDAR systems and integrated solutions on YellowScan and DJI drones. Through this article we want to find out what are the advantages and disadvantages of each system and which one is the most suitable for which scenario. If you want to find out too, let’s go to the first section, namely:

Features and general description

Survey Ultra 3 (YellowScan)

With its 360° field of view, the YellowScan Surveyor Ultra meets the needs of vertical mapping and mobile mapping when combined with Fly & Drive. Expect unparalleled penetration into vegetation thanks to this system’s 32 laser beams.

Precision 3 cm
Accuracy 2.5 cm
Flight speed 10 m/s
Maximum Altitude (AGL) 140 m
Range Up to 300 m
Laser scanner Hesai XT32M2X
Integrated GNSS SBG Quanta Micro
FOV scanner 360° x 40.3°
Echoes per capture Up to 3
Pulses per second Up to 640,000
Scan frequency Up to 20 Hz
Integrated RGB Global Shutter 2 MP camera
Weight 0.98 kg without batteries
Dimensions L 153 x W 113 x H 117 mm
Autonomy 1.2 hours with the battery
Power consumption 20 W
Operating temperature -10°C to 40°C

Zenmuse L2 (DJI)

The Zenmuse L2 integrates a DJI-developed high-precision IMU system and a 4/3 RGB CMOS mapping camera within the LiDAR, providing DJI flight platforms with more accurate, efficient and reliable geospatial data acquisition. When used with DJI Terra, it provides a turnkey solution for high-precision 3D data collection and post-processing.

Precision 5 cm
Accuracy 5 cm
Flight speed 10 m/s
Maximum altitude (AGL) 150 m
Range Up to 500 m
Laser scanner IEC 60825-1:2014
Integrated GNSS RTK
Scanner FOV 70°x 75°
Echoes per capture Up to 3
Pulses per second Up to 240,000
Scan frequency Up to 24 Hz
Integrated RGB 4/3 CMOS 20 MP camera
Weight 0.905 kg
Dimensions L 155 x W 128 x H 176 mm
Gimbal 3-axis (tilt, roll, pan)
Power consumption 20 W/ 58W (max.)
Operating temperature -20°C to 50°C

Flight parameters

We flew each of the two LiDAR systems in four different situations, as you’ll see a little below. The flights had the following settings:

Surveyor Ultra 3 Zenmuse L2
Altitude 65 m 65 m
Flight speed 10 m/s 10 m/s
Overleap Side 50%/Front 10% Side 50%/Front 10%
Area 32 ha 32 ha
Flight time 12 minutes 12 minutes
Point density 640 000 240 000
Positioning corrections Fixed base RTK

LiDAR data – processing software

YellowScan CloudStation

YellowScan Cloudstation software is designed by cartographers for complex and long-duration flight operations. It is licensed software with 1 year maintenance including support and updates.

YellowScan CloudStation comes as a fully integrated solution

  • Easy to use graphical interface
  • Automatic or custom band selection
  • Processing and export in .LAS format
  • Advanced visualization tools
  • Project Settings: Coordinate System, LiDAR Profile, Angle Range

General characteristics

  • It works on Windows 10
  • Automatic updates
  • Offline license mode
  • Optional additional license seats

Display options

  • Cloud color (altitude, intensity, echo, etc.)
  • Measurement instruments
  • 3D view
  • EDL filter
  • Vertical cut

Point cloud processing

  • Project settings (coordinate system, LiDAR profile, angle range, etc.)
  • Automatic band selection
  • Process and export to .LAS format

Exports

  • LAS & LAZ 1.2
  • LAS & LAZ 1.4
  • DSM (Digital Surface Model)
  • DTM (Digital Terrain Model)
  • DHM (Digital Height Model)

All these exports can be exported in different coordinate systems, including Stereo 70 with 2 cm precision and accuracy.

DJI Terra

DJI Terra is fully integrated software designed to transform aerial data obtained with DJI drones into digital 3D models and accurate maps.

Key features

  • Intuitive interface: Easy to use, even for novice users.
  • Intelligent mission planning: Generate optimized flights to get the data you need.
  • Automatic data processing: Perform complex calculations quickly and efficiently.
  • Advanced 3D Modeling: Create detailed 3D models and accurate 2D maps.
  • Personalized analytics: Get valuable insights from your data.

Applications

  • Mapping: Create accurate 2D maps and 3D models for a variety of applications such as urban planning, infrastructure surveying, and agriculture.
  • 3D Modeling: Generate realistic 3D models for visualization, data analysis, and design.
  • Inspection: Perform detailed inspections of infrastructure, buildings and other assets.
  • Surveying: Create accurate topographic plans for engineering and construction projects.
  • Farming: Monitor crop health, plan farming operations and optimize production.

Benefits

  • Increase efficiency: Automate workflows and save time.
  • Get Better Insights: Analyze aerial data to get a more complete picture of your project.
  • Make smarter decisions: Use the insights you get to make better, more informed decisions.

Exports

  • LAS
  • JSON
  • DSM (Digital Surface Model)
  • DTM (Digital Terrain Model)

All these exports can be exported in WGS 84.

Advantages and disadvantages

Advantages of Ultra 3 Advantages of Zenmuse L2 Disadvantages of Ultra 3 Disadvantages of Zenmuse L2
High density of points per square meter Rotating gimbal Built-in RGB camera resolution Low point density
Possibility of export in different coordinate systems Built-in RGB FHD camera The need for a base for corrections/ Post processing Low accuracy and precision
Accuracy and centimeter precision on X, Y, Z Integration with Pilot 2 Poor penetration of vegetation
360° capture angle Ability to use RTK Limiting exports to a single coordinate system
Compatibility with a car Internet connection dependency
Integrated RGB camera Controller-drone connection dependency
Increased efficiency
Versatility
Good penetration of vegetation

Usage examples

1. Scanning of low voltage lines

YellowScan Survey Ultra 3

DJI Zemmuse L2

2. Telecommunication towers

YellowScan Survey Ultra 3

DJI Zemmuse L2

3. Analyzing the land surface and obtaining a digital land model of a vegetated area

YellowScan Survey Ultra 3

DJI Zemmuse L2

YellowScan Survey Ultra 3

DJI Zemmuse L2

4. Extracting the ground footprint of the buildings

YellowScan Survey Ultra 3

DJI Zemmuse L2

Conclusion

As a conclusion, the DJI Zenmuse L2 LiDAR system is well suited for small, simpler projects that do not require a high level of detail, while YellowScan’s Surveyor Ultra 3 is built to give detailed results in more difficult conditions within complex scanning projects.

If you liked this article, you can also check out this case study on how you can get the ground footprint from the point cloud in Stereo 70, using a multirotor drone and a LiDAR system from YellowScan: Case Study: How to get building footprint from point cloud in Stereo 70, EPSG:3844.

If you want to know more about LiDAR technology and the fields in which it finds applicability, see this article: How can drones with LiDAR systems (as payloads) help you in your field of work? – Introduction.