discover how to produce highly accurate 3D maps utilizing a conventional drone and ground control points, wiht exact coordinates obtained from an ArduSimple RTK-calibrated surveying kit. This guide illustrates how to achieve survey-grade outcomes without the need for an RTK drone. More information > >
Generating precise 3D maps of terrains or sites no longer necessitates the use of advanced drones equipped with RTK positioning technology. Whether you are a land surveyor, engineer, construction expert, or an enthusiastic UAV operator, it is indeed feasible to create centimeter-level accurate photogrammetric maps using a standard GPS drone, provided you follow the correct procedures and utilize the right tools. This guide details how to attain survey-grade mapping precision through the use of ground control points (GCPs) and photogrammetry software, even when employing non-RTK drone systems.
RTK drones integrate highly precise georeferenced coordinates into each image during capture,greatly streamlining the mapping process. Conversely, non-RTK drones rely on consumer-grade GPS, which often results in positional inaccuracies of several meters. To rectify these errors, GCPs serve as external geospatial references. These are physical markers strategically placed within the mapping area, with their exact coordinates determined using an RTK-calibrated surveying kit.When processed through photogrammetry software, these known reference points enable accurate spatial adjustments across the entire map.
To begin,you will require the following equipment: a drone equipped with a camera and SD card,a smartphone,a computer,physical ground control point markers,and an RTK-calibrated surveying kit for obtaining precise ground coordinates. The software suite includes SW Maps for documenting GCP locations, Dronelink for planning and automating flight missions, and WebODM for transforming aerial images into 2D and 3D outputs. WebODM is a robust open-source photogrammetry engine that can be self-hosted or accessed via a commercial cloud version, making it user-friendly for those with limited technical expertise.
The process involves distributing GCP markers throughout the survey area, accurately measuring their positions with the RTK surveying kit, and logging the coordinates in SW Maps.Next, you will conduct a structured grid mission with your drone, capturing high-resolution overlapping images. The photographs, along with the recorded GCP data, are then imported into WebODM for processing. By aligning the images with the known GCP coordinates, WebODM can produce orthomosaics, point clouds, and digital elevation models with centimeter-level accuracy, despite the inherent GPS limitations of the drone.
By meticulously following each step of this method,users can circumvent the financial constraints associated with RTK drone systems while still generating professional-grade geospatial datasets suitable for surveying,construction planning,volumetric analysis,and more.
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