PROBLEMS
IN 3D SCANNING
Drones and 3D technology are revolutionizing the way work is completed in many industries ranging from architecture, engineering, and construction (AEC) to civil infrastructure, processing, power, and utilities.
SCANNER TYPES
What is LiDAR?
LiDAR is a remote sensing technology that uses a laser pulse to collect measurements. This data can then be used to create 3D models and maps of objects and their environment. It can be used to measure distances (ranging) by illuminating the target with laser light and measuring the time required for the reflection of the light to return to the sensor.
LiDAR stands for Light Detection and Ranging.
LiDAR calculates how long it takes for light to strike an object or surface and be reflected back into the scanner. Knowing the speed of light, these distances are then calculated. They are known as "time of flight" measurements.
Depending on the equipment, LiDAR can receive up to several million reflections per second from distances from several meters to hundreds and thousands of meters. The set of reflections obtained is called a point cloud.
The data obtained from LiDAR is used in geodesy, cartography, construction, architecture, and precision agriculture. Point clouds can produce an accurate digital elevation model. DEM is very important for design or earthwork because it accurately conveys even the smallest landforms.
LiDAR can also be used to monitor power lines. These scans provide the exact geometry of wires and estimates of the amount of sag, threatening vegetation, and deviation of the support from the vertical axis or design position.
DIGITAL PHOTOGRAMMETRY
Unmanned aerial photography helps teams to quickly, efficiently, safely, and affordably gather valuable aviation knowledge. It helps shape decision-making, improves communication, and increases revenue and results.
Digital photogrammetry allows you to combine sets of photographs of an object in order to obtain a 3D model. Using image parallax, automated systems calculate the parameters of image orientation, compare points and objects on them, and then combine these images into a single photogrammetric model.
Drone photography allows you to take a snapshot of any part of even the most inaccessible or tall object or building. The use of GNSS and RTK technologies allows you to achieve data accuracy of less than 1 cm
SCANNING PROBLEMS
All technologies have shortcomings. For example, LiDAR scans are weather-dependent and cannot be performed in rain or fog. The accuracy of the data obtained with the LiDAR is less than when shooting with RGB cameras. At the same time, the use of cameras alone will not allow obtaining an accurate DEM of forested areas.
Using only cameras or LiDAR does not accurately reflect the model. Factors such as glass, wires, antennas are not restored using digital photogrammetry. Using only LiDAR, it is impossible to provide a photographically accurate texture of the created model. It is best to use both technologies in combination.
Most drone surveys are completed without an accurate GPS receiver. This makes it almost impossible to compare models at different times. The exact relative position of the resulting models will allow identifying the slightest deviations from the vertical.
It is very inconvenient to take measurements with existing programs. Drawing generation is not automated, and 3D measurability is not fully utilized.
OLD ARCHITECTURAL SCANNING
Scanning technologies are used to create copies of objects or to capture the territory of design or construction.
Scanning can be used to create detailed models of houses, often to preserve historically important heritage.
During the construction and installation stages, drone monitoring permits the acquisition of information regarding project progress and excavation volumes. Photorealistic models detail the geometric and spatial characteristics of buildings and other infrastructural projects, including landscaping of adjacent territories. In addition, simulation materials can be used as visual presentation material for potential customers or investors.
A 3D terrain model created by UAV data is a powerful tool in the hands of designers. With the help of 3D drone technologies, you can fully explore the landscape features of the territory. This one-time coverage of the entire development area will help predict possible natural changes and choose the optimal position of engineering communications. Digital surface models and DEMs are fully compatible with GIS and CAD. This will enable spatial analysis and assessment of excavation volumes.
During construction, it is important to keep track of progress. By constantly comparing the resulting model with the design data, you can identify discrepancies at a very early stage. In addition, data from drones are also used to determine volumes such as pits, ditches, and building materials either automatically or manually Photo, video and 3D models help safety engineers track all hazards and prevent potential dangerous situations.
DRONE USAGE FOR MODERN WORLD
Landscape scanning
Drones allow you to quickly obtain maps of the surface and objects on it. Such data are used in geodesy, cadastre and landscape design. Drones can oversee large areas, making UAV projects much shorter and cheaper for the customer. In comparison, a 100-acre project will be completed 3.5 times faster if drones are used than conventional ground surveys.
Mining scanning
In open pit mining, the availability of accurate and up-to-date geometric data on the surface of a quarry, section or mine is the most important condition for the successful solution of surveying tasks. Ground-based survey methods require a lot of time for field work. Office work on the creation and updating of cartographic documentation is influenced by human factors. This leads to distortions in the display of the relief, and ultimately reduces the accuracy and quality of mine surveying.
Digital surface models obtained using UAV technologies are much more detailed than models built on land surveys. They are generated in a regular grid with centimeter spatial resolution.
NEW WAYS TO USE DRONES
Delivery
Digital surface models obtained using UAV technologies are much more detailed than models built on land surveys. They are generated in a regular grid with centimetre spatial resolution.
Geophysics
High-precision UAV surveys became a great way to study magnetic field data with the speed of aerial photography and the accuracy of ground reconnaissance. Thanks to the improved flight control system, it became possible to fly at different heights and different speeds, with general and detailed relief flow. The magnetic survey also found its application in solving archaeological problems, searching for man-made objects, solving problems in regional structural geology and engineering and geological surveys.