DJI Zenmuse L2

Accurate LiDAR and photogrammetry payload

The DJI Zenmuse L2 is a highly-accurate and efficient drone surveying payload.

It integrates a LiDAR module, a high-accuracy IMU, RGB camera, and a 3-axis stabilised gimbal system.

The L1 supports up to 5 returns and has a maximum multiple return rate of 1,200,000 pts/s – capturing the details of complex structures and delivering centimetre-accurate reconstructions.

The 4/3 CMOS 20MP RGB mapping camera can be used for photogrammetry and for creating true colour point clouds.

Integrate the L2 with the DJI M350 RTK or the DJI M300 RTK (with the DJI RC Plus controller).

The L2’s IP54 rating allows it to be operated in wet or foggy environments. Also collect data at night.

Deploy the L2 across a range of industry verticals, such as energy, AEC, forestry, and public safety.

The L2 is a substantial upgrade compared to its predecessor, the L1, with higher sampling rates compatible with higher returns, a larger RGB sensor, and increased surveying efficiency.

Powerline Reconstruction

 

The L2 is able to detect small objects during a survey – as shown by this vertical cross-section of power lines and transmission towers.

LiDAR Module

The L2 offers up to five returns, with a maximum return rate of 1,200,000 points per second, and has a laser pulse emission efficiency of 240kHz.

It enables the L2 to easily generate accurate elevation data in dense forest fields and extract it into DTMs, as well as detect small objects on a survey site and map complex structures.

• Detection Range: 450m @ 50% reflectivity, 0klx; 250m @ 10% reflectivity, 100klx.
• Point Cloud Rate: Single Return Max – 240,000 pts/s. Multiple returns, max 1,200,000 pts/s.
• Scanning Modes: L2 has non-repetitive scanning pattern and repetitive scanning pattern. This increases the likelihood of objects and other details being detected within the FOV.
• Highly Accurate: Horizontal 5cm @ 150m flight altitude; Vertical: 4cm @ 150m flight altitude.
• Efficient: Collect data while flying at up to 15m/s.

RGB Camera

The RGB camera can be used for photogrammetry.

It also allows the L2 to output reality models and true colour point clouds, including real-time point cloud colouring (with parameters of Reflectivity, Height, Distance, RGB).

Use the RGB camera to capture video, as well as still imagery.

Key features of the RGB camera include:

• 4/3 CMOS sensor
• 20MP
• 84° FOV
• Mechanical shutter (to eliminate rolling shutter blur), high-speed burst with 0.7s interval
• 4K @ 30fps video

High-accuracy IMU

The L2’s high-accuracy IMU (inertial measurement unit) is essential for quality LiDAR data collection.

• Horizontal Positioning Accuracy: RTK FIX: 1cm + 1ppm
• Vertical Positioning Accuracy: RTK Fix 1.5cm + 1 ppm

As a bonus, the IMU on the L2 does not require a warm-up, and is ready to operate after start-up.

One-stop Processing

Process L2 data through DJI Terra.

DJI Terra supports exporting point cloud models in the following formats:

• PNTS
• LAS
• PLY
• PCD
• S3MB

DJI Terra updates – such as added support for generating a DEM for LiDAR point cloud reconstruction, ground classification for LiDAR data; and automatic GCP marking – provide a more seamless and comprehensive workflow.

After processing through DJI Terra, the data can be imported into third-party software, such as DJI Terrasolid, for further manipulation and analysis.

L2 vs L1

L2 provides significant upgrades for surveying

The L2 is an upgraded version of the L1. Key upgrades include:

• More efficient payload: Does not require 5-10 minute period for IMU warm up, which is needed when using the L1.
• Accuracy at speed: Accurately capture data at 15 m/s flight speed. Recommended flight speed for L1 is 8 to 10 m/s.
• Improved return pulse: L2’s maximum return pulse is Penta, as opposed to L1’s Triple return, resulting in improved ability to scan through areas of vegetation and capture complex structures.
• Higher sampling rates: Higher sampling rates compatible with higher returns: L2’s pulse rate is 240 kHz with 5 returns, L1 achieves 160kHz with Triple-echo mode.
• Increased Accuracy: Greater absolute accuracy compared to the L1 sensor.
• Upgraded RGB Sensor: L2 has a 4/3 CMOS sensor, compared to L1’s 1-inch sensor.