Top 7 Features of the DJI L1

Responding to high demand from AEC and surveying industries, the Zenmuse L1 addresses the need for a potent yet user-friendly LiDAR drone solution.

Despite its presence for over half a century, the transformative potential of Light Detection and Ranging (LiDAR) data has only come to the forefront across industries in the past decade. LiDAR technology is now acknowledged as a pivotal element in constructing precise reality models within the surveying sector.

Why is this the case? In scenarios of low light or areas covered by dense canopies, traditional aerial photogrammetry methods struggle to ascertain the true surface of the earth. In contrast, drones equipped with LiDAR sensors can generate highly accurate point cloud representations of intricate environments and structures.

Nonetheless, the adoption of commercial drone LiDAR technology has been relatively slow compared to photogrammetry. This delay can be attributed to the scarcity of lightweight yet robust and budget-friendly airborne LiDAR systems, or the intricacies involved in processing and categorizing the voluminous data. Despite these challenges, aerial LiDAR technology has yet to fully shine.

The tide is on the brink of turning. With an anticipated release in early 2021, the Zenmuse L1, DJI's inaugural drone LiDAR sensor, is poised to be a game-changer. This innovation will significantly advance the democratization of LiDAR technology through its efficiency, precision, and affordability.

Discover the top 7 features of the L1 that are bound to ignite your enthusiasm:

Utilizing an inertial measurement unit (IMU), a drone can effectively gauge real-time 3-axis acceleration and angular velocity, enabling the computation of vital metrics such as speed, position, and altitude angle. The presence of a high-precision IMU is essential to ensure the quality of LiDAR data collection, as it prevents your point cloud from becoming an arbitrary assemblage of points.

Incorporating an industrial-grade IMU, the Zenmuse L1 is engineered for exceptional performance. During typical operations, the L1 boasts an IMU accuracy of 0.025° (roll/pitch) and 0.15° (yaw). Elevating its reliability and accuracy, the solution integrates a vision sensor for precise positioning and a dual-frequency GNSS receiver. Consequently, the L1 achieves a relative survey-grade accuracy of 5cm and an absolute accuracy of 10cm when flying at a 50m altitude.

In contrast to many other LiDAR drone systems available, the L1 sets itself apart by including a 3-axis stabilized gimbal in the package, eliminating the need for separate stabilizing solutions. This integrated design ensures that any unintended rotational motion of the drone, encompassing tilt, roll, and pan, is swiftly stabilized within a range of ±0.01°. Consequently, even at elevated scan rates, the point distribution remains consistent and even. This advancement substantially minimizes the likelihood of data gaps, consequently reducing the expenses associated with the necessity for re-flight.

As the L1 is seamlessly integrated with DJI's flight management system, you gain access to fully automated mount control, heightened efficiency in data collection, and impeccably aligned imagery, all contributing to the precision of geo-referenced data acquisition missions.

As the complexity of use cases intensifies, it's no longer feasible to compel surveyors to make a choice between LiDAR and RGB imagery. Similarly, investing double the time and resources to obtain true-color point cloud models isn't a pragmatic approach. Addressing these challenges, DJI's adaptable and economical drone LiDAR mapping solution, the Zenmuse L1, incorporates a 1-inch 20MP CMOS sensor directly on board. This dual-purpose setup not only facilitates capturing photos and videos but also supplies real-time color information for the point cloud data during scanning. Consequently, the L1 is capable of producing authentic color point clouds and reality models.

Incorporating a 20MP 1-inch CMOS Sensor equipped with a mechanical shutter, the Zenmuse L1 eradicates rolling shutter distortion. Astute users will identify this sensor as the very one utilized in our highly acclaimed survey-grade mapping drone, the Phantom 4 RTK. Just like its counterpart, the P4 RTK, the Zenmuse L1 offers the potential to attain a ground sample distance (GSD) of 2.74 cm when flying at an altitude of 100 meters, should you opt to employ it for photogrammetry purposes.

Sporting a detection range stretching up to 450 meters, the Livox LiDAR module of the L1 orchestrates an impressive point rate of 240,000 points per second. However, the L1 offers the flexibility of accommodating up to 3 returns per laser shot. Consequently, this point rate scales up to a staggering 480,000 points per second during operations involving multiple returns.

This multi-return capability empowers users of the L1 drone LiDAR to effortlessly generate elevation data within densely wooded areas and subsequently extract it into Digital Elevation Models (DEM) and Digital Surface Models (DSM). The utilization of multiple returns also facilitates the task of data analysts who can discern and categorize diverse objects within a point cloud, ranging from overhead wires to various assets at a construction site.

The L1 stands out as the sole aerial LiDAR sensor supporting both a line scan mode and a distinct non-repetitive scanning pattern, an innovation pioneered by Livox. In this specialized mode, the area scanned within the field-of-view (FOV) expands in sync with the integration time. This approach significantly enhances the probability of detecting objects and finer details within the FOV. Furthermore, as the drone LiDAR sensor dedicates more time to scanning an area, the resulting data showcases heightened resolution compared to conventional line scanning. On the topic of the FOV, the L1's non-repetitive scanning mode encompasses a wide 70.4° (horizontal) × 77.2° (vertical) range.

Learn more about Non-Repetitive Scan Mode > > >

Through the Non-Repetitive Scan Mode, the DJI Zenmuse L1 achieves swift and comprehensive coverage of the designated area. This mode empowers the sensor to gather data from various directions rather than solely along a predetermined plane.

Pairing the formidable L1 with DJI's premier commercial drone platform, the Matrice 300 RTK and Matrice 350 RTK, along with the DJI Terra post-processing software, results in a seamlessly integrated and comprehensive solution for precise real-time 3D data acquisition. Operating at an altitude of 100 meters and a speed of 10 meters per second, a solitary flight employing the M300 RTK and L1 is capable of amassing data spanning a vast 2 square kilometers.

Simply use the Point Cloud LiveView feature to confirm that you’re capturing the right data without having to land or wait for post-processing, and save yourself from re-flying and rework. And once you have the right data, DJI Terra becomes your one-stop post-processing solution. The software will seamlessly fuse the IMU and GNSS data for point cloud and visible light calculations, in addition to conducting POS data calculations so you can effortlessly generate reconstructed models and accuracy reports.

DJI is dedicated to making cost-effective and adaptable LiDAR solutions available in the skies is steadfastly growing. As LiDAR imagery becomes more accessible, its potential applications will transcend beyond AEC and surveying. For instance, environmental management agencies can harness drone LiDAR to glean insights into canopy dimensions, vegetation density, stock volume, and growth patterns. Industries prone to high risk, such as oil and gas, mining, and telecommunications, can reap advantages from comprehensive asset modeling to facilitate automated inspections and more. Even emergency responders can utilize true-color point clouds to attain real-time situational awareness, even during low-visibility nighttime scenarios.