Methods and Applications of 3D Ground Crop Analysis Using LiDAR Technology: A Survey

Abstract

Light Detection and Ranging (LiDAR) technology is positioning itself as one of the most effective non-destructive methods to collect accurate information on ground crop fields, as the analysis of the three-dimensional models that can be generated with it allows for quickly measuring several key parameters (such as yield estimations, aboveground biomass, vegetation indexes estimation, perform plant phenotyping, and automatic control of agriculture robots or machinery, among others). In this survey, we systematically analyze 53 research papers published between 2005 and 2022 that involve significant use of the LiDAR technology applied to the three-dimensional analysis of ground crops. Different dimensions are identified for classifying the surveyed papers (including application areas, crop species under study, LiDAR scanner technologies, mounting platform technologies, and the use of additional instrumentation and software tools). From our survey, we draw relevant conclusions about the use of LiDAR technologies, such as identifying a hierarchy of different scanning platforms and their frequency of use as well as establishing the trade-off between the economic costs of deploying LiDAR and the agronomically relevant information that effectively can be acquired. We also conclude that none of the approaches under analysis tackles the problem associated with working with multiple species with the same setup and configuration, which shows the need for instrument calibration and algorithmic fine tuning for an effective application of this technology.

Seedling-YOLO: High-Efficiency Target Detection Algorithm for Field Broccoli Seedling Transplanting Quality Based on YOLOv7-Tiny

“…Therefore, this study the conditions of seedlings that impact yield and aims to develop fas tion algorithms for these specific categories. The current prevalent technologies for field detection include m ultrasonic sensor detection [14], and 3D Light Detection and Rangin [15,16]. Ultrasonic sensors and 3D LiDAR can detect the presence o within an area, yet they face difficulties in accurately distinguishing of these seedlings.…”

“…Cui, et al [21] enhanced the YOLOv5s by a head structure and incorporating a transformer, developing a rice m tion and counting model with a precision of 93.2%. Wu, et al [22] im replacing its Neck network with the Slim-Neck network, developi missing seedling detection model and proposing a method for predi The current prevalent technologies for field detection include machine vision [12,13], ultrasonic sensor detection [14], and 3D Light Detection and Ranging (LiDAR) detection [15,16]. Ultrasonic sensors and 3D LiDAR can detect the presence of vegetable seedlings within an area, yet they face difficulties in accurately distinguishing the planting quality of these seedlings.…”

UAS Quality Control and Crop Three-Dimensional Characterization Framework Using Multi-Temporal LiDAR Data

“…Compared with indirect stereo-vision techniques, light detection and ranging (LiDAR) systems comprising a laser scanner, an inertial measurement unit (IMU), and a Global Navigational Satellite System (GNSS) construct 3D structures using direct geo-referencing techniques [27]. Direct georeferencing precisely measures the location, geometry, and orientation of any object using the laser sensor integrated with GNSS and IMU with cm level ranging accuracies [23,28,29]. Compared with diffused sunlight-based optical sensors, laser beams of smaller footprints are capable of penetrating through smaller canopy gaps to decode the underlying canopy and topography structural complexities [24,30].…”

“…Compared with diffused sunlight-based optical sensors, laser beams of smaller footprints are capable of penetrating through smaller canopy gaps to decode the underlying canopy and topography structural complexities [24,30]. In recent times, with the development of small-size highly precise IMU, GNSS, and laser scanners, the multisensory integration conundrum onboard UAS systems has become more operational than ever [22,28,31]. Currently, several affordable UAS laser scanners (ULSs) are available for commercial applications capable of acquiring high-quality LiDAR point clouds in a wide area capacity [19,22,32].…”