LIDAR Aerial Survey

Such data is called Terrain - it is a surface based on TIN (Triangular Irregular Network) with variable resolution, constructed from measurements stored as spatial objects in a geodatabase. They are typically created using LiDAR and photogrammetric sources. Terrain datasets are part of a geodatabase and include objects used to create them.

Common classes of spatial objects that function as data sources for Terrain include:

• Multi-point classes of spatial objects: 3D point clouds created from data sources like LiDAR.
• 3D point and line classes of spatial objects: Created on photogrammetric workstations using stereo imagery.
• Study area boundaries: Used to define the extent of the Terrain dataset.

Terrain dataset rules control how objects are used to determine the surface.

The accuracy of the equipment is no more than 1-2 mm. This is very high compared to traditional measuring technologies.

Terrestrial laser scanning is the most modern method of field investigation. It is a new technology that avoids unnecessary waste in further design and construction. In complex cases, it is the only possible way to obtain accurate information about the configuration of an object, for example, in hard-to-reach places. With the help of laser scanning it is possible to create an actual digital model showing the state of the object in detail. By rotating the scanner horizontally by 180°, a full sphere is scanned except for the field below the device itself. After the data cloud is processed by the computer, distances to points and their coordinates become known, and a real-time visual model of the surrounding space is created. The number of points in the array can reach several tens of millions, so the real-time image of the object is as accurate and reliable as possible. To combine individual scans into a single field of points, special stamps are used. During processing, all scans are combined - stitched together - to produce a point cloud containing detailed information about the building parameters. This is the final product of field work. Later it can be used for various purposes - three-dimensional modeling of the object, determination of its geometry, clarification of deformations of parts or individual structures.

Before traditional methods such as theodolite surveying or measurements with a laser rangefinder, 3D scanning possesses the following advantages:

• Quick acquisition time;
• Obtaining a large amount of information about the object;
• High speed and accuracy of measurements;
• Completeness of the acquired information;
• Simplicity in the application of the equipment;
• Applicability of the survey results for various purposes;
• Possibility to conduct surveys both during the day and at night;
• Remote data acquisition, ensuring safety when surveying hard-to-reach areas;
• Data storage in electronic format, enabling its use for reconstruction, modernization, or monitoring of building, structural, and architectural deformations.

As for the disadvantages, the following can be noted:

• Impossibility of surveying in the absence of visibility;
• Challenges in scanning glass structures or completely smooth surfaces;
• Lack of geodetic georeferencing. The scanner cannot independently determine its geographic coordinates, thus requiring the use of other geodetic instruments, such as a theodolite or GNSS receiver;
• Dependency on weather conditions.

During LIDAR aerial survey is carried out from several points of the scanner installation. Necessary settings are pre-set to perform measurements in automatic mode with a specified discreteness (laser beam pitch) Laser scanning is a modern method of taking accurate geodetic data to obtain 3D models of objects. It is necessary to use special equipment to carry out the work, which allows you to obtain highly accurate data on objects. Laser scanning companies can provide a wide range of surveying, surveying and design services for buildings and structures. They use state-of-the-art scanning technology to obtain accurate data, which allows them to create accurate 3D models of objects and speed up the work of creating projects. Laser scanning also allows you to survey existing buildings and structures, determine their condition and make repairs if necessary. With the help of the obtained data it is possible to create drawings of objects, taking into account their design features and parameters. Laser scanners will also help to determine the optimal conditions for the construction of new facilities, taking into account the geological and geodetic parameters of the territory. Thanks to the use of laser scanning, specialists can obtain accurate data about objects, which facilitates design and allows to speed up the work of creating projects. As a result, laser scanning is an indispensable tool in the design and construction of buildings and structures, and geodesy and specialized equipment help to carry out these works even more accurately and efficiently.

Three-dimensional modeling is used to create digital models of objects:

• that require reconstruction or major renovation, with complex spatial planning solutions, irregular axis intervals, and varying number of floors;
• that are cultural heritage;
• such as elevator shafts and collectors;
• of industrial facilities with complex configurations;
• of structures in the oil and gas industry (tank calibration and more).

Lidar and remote sensing allow scanning of urban environments and monitoring landscape changes. The obtained data is processed and converted into a point cloud, which is used for creating 3D models. The accuracy of measurements and data processing enable the application of laser scanning in various fields, such as topography, cartography, engineering surveys, and industrial safety.

Laser scanning has also found applications in architectural design, construction, and reconstruction. With precise geometry and the ability to create 3D models, more accurate drawings can be produced, reducing errors in the design process. Virtual reality and computer vision enable viewing objects from different angles and planning projects more effectively.

An essential component of laser scanning is GIS, which allows for analysis and management of the scanned data. Additionally, the use of aerospace technologies and accurate positioning improves the quality of the obtained data.

In general, laser scanning and point cloud processing are essential tools in the modern world, providing accurate data and its utilization in various fields, such as topography, cartography, engineering surveys, and industrial safety.

• Terrestrial Laser Scanning (TLS) is used for high-precision scanning of small objects.
• Aerial Laser Scanning (ALS) is optimally used for studying large areas with an area of 1000 hectares or densely built-up territories.
• Mobile Laser Scanning (MLS) performs well in scanning road networks, railways, and other linear infrastructure objects.

The mobile laser scanning system consists of the following components:

• A mobile platform designed to absorb shocks and vibrations.
• An odometer - a device for measuring the distance traveled by the vehicle.
• A control unit, user interface, and specialized software for managing the scanning process.
• A laser scanning unit (one or multiple units depending on the tasks).
• An integrated GPS/IMU navigation system - an inertial navigation system IMU combined with Global Positioning System (GPS) for precise positioning.
• High-resolution digital cameras.
• A base station or a network of GPS base stations and receivers for global navigation satellite systems.

The areas of application for laser scanning include:

• Transportation infrastructure
• Cities and settlements
• Energy facilities
• Large industrial enterprises
• Port and harbor infrastructure
• Quarries and open-pit mines

LIDAR aerial survey is used for various purposes, including:

• Topographic surveying at scales of 1:500 and finer
• Data collection for thematic GIS
• Design, reconstruction, and construction of transportation system objects
• Technical condition analysis of support structures, contact lines, road pavement, and roadside infrastructure
• Determining critical vegetation proximity to contact lines and other road infrastructure objects
• Detection of unauthorized construction and activities within road reserve areas
• Inventory and documentation of road infrastructure objects
• Traffic optimization
• Monitoring and maintenance of road pavement and roadside infrastructure
• Determining track gauge and volume of road repair and restoration work
• Control of actual volumes and quality of road laying or restoration work
• Route selection for transporting oversized cargo
• Road expansion and roadside infrastructure planning
• Architecture and urban planning, territory planning and management
• Precise location determination of various terrain features and infrastructure objects
• Determining suitable locations for advertising structures
• Analysis of compliance with regulatory requirements for existing advertising structures
• Inventory and documentation of advertising structures
• Data collection and updating for restoration and reconstruction of objects
• Updating large-scale topographic plans of road urban networks, avenues, squares, and urban street development
• Vegetation survey (shrubs, trees, etc.)
• Surveying and determining geometric parameters of aerial communication lines (cables, pipelines, etc. over streets and roads) and multi-level structures (bridges, viaducts, etc.)
• Mutual coordination of engineering structures in design on densely developed territories
• Asset management and documentation of administrative and residential buildings
• Creation of high-resolution 3D models of cities
• Creating virtual images of planned objects, assessing their aesthetic value, and harmoniously integrating them into the existing urban landscape
• Solving problems of comprehensive urban development, transportation, engineering and social infrastructure, and urban improvement, assessing spatial integrity
• Highly accurate landscape and visual analysis of cities from the height of human growth
• Rapid measurement of buildings and structures. Creating models and survey drawings of building facades and structures
• Inventory and documentation of power transmission lines
• Determining sagging of wires, geometry of supports, and other geometric parameters
• Identifying critical vegetation proximity to power transmission lines
• Modeling and documentation of energy nodes and substations
• Determining volumes of work performed in open mines and quarries
• Safe and regular mine surveying measurements
• Determining warehouse volumes

I Stage: Preparation for Scanning
• Route selection for scanning
• Selection of base station installation locations
• Installation of the system on the vehicle

II Stage: Data Collection
• System configuration verification and control
• Data collection and storage
• Management of high-capacity storage devices
• Analysis and visualization of measurement data with coordinate system alignment
• Quality control of acquired data
• Preservation of scanning history, scanning parameters, and operator actions
Results of the Scanning:
• Raw laser scanning data
• Raw video camera data
• Raw position and orientation data from the INS/GNSS system
• Raw data obtained from GPS base stations
Software included in the manufacturer's mobile scanning system control unit is used at this stage for data collection.

III Stage: Initial Data Processing
Initial data processing is performed using software included in the manufacturer's mobile scanning system control unit and INS/GNSS data post-processing software.
• Obtaining trajectory and position data in the WGS84 coordinate system
• Combination of laser scanning data and trajectory, coordinate transformation
• Visualization, calibration, and correction of scanning data
• Visualization and correction of video images
• Statistical analysis of alignment, verification of compliance with specified accuracy parameters

IV Stage: Data Post-Processing
Data post-processing at this stage can be performed using various laser scanning point processing, classification, and CAD modeling software, such as AutoDesk, Bentley Microstation, Terrasolid, Intergraph, etc.
Data post-processing may include:
• Classification of laser scanning points into corresponding layers ("ground - non-ground," "hydrography," "roads," "railways," "vegetation," "structures," "cables," "supports," "contact lines," etc.);
• Creation of 3D vector models of surveyed objects
• Creation of digital terrain models
• Creation of seamless orthomosaics for the entire survey area
• Creation of digital terrain models
• 3D modeling of objects:
o Creation of virtual models of terrain and objects
o Creation of videos, panoramas, animations
o Creation of photo plans
• Creation of thematic processing results tables:
o Assessment of geometric quality of road construction
o Road profiling
o Calculation of transverse and longitudinal slopes of roads
o Calculation of oversized dimensions
o Calculation of visibility zones
o Determination of volume of earthworks
o Determination of volume of construction materials used (sand, gravel)
o Determination of volume and area of road pavement
o Quality control of road pavement (undulation, inclination, rutting)

Laser scanning of buildings (or laser scanning of surfaces, LIDAR - Light Detection and Ranging) is a technology that allows you to create a three-dimensional model of objects and surfaces with high accuracy and detail. The application of laser scanning of buildings can be useful in many industries such as architecture, construction, engineering, surveying and others. The working principle of laser scanning is to measure the distance between the instrument and the object using a laser beam. The laser beam is directed to the surface of the object, reflected from it and returned back to the instrument. From the delay time of the signal, the distance to the surface of the object can be determined. When scanning buildings with a laser, all visible surfaces of the building are scanned. The resulting data is used to create an accurate three-dimensional model of the building, which can be used for various purposes, such as design, repair, restoration or to create a virtual tour. One of the main advantages of laser scanning of buildings is the high accuracy and detail of the data obtained. This allows the creation of accurate three-dimensional models of buildings that can be used for a variety of purposes. In addition, laser scanning of buildings can be carried out relatively quickly, which saves time and resources when designing or renovating buildings.

1. Creating 3D models of objects and buildings - laser scanning allows for the creation of accurate 3D models of buildings, which can be useful for design, renovation, and construction purposes.

2. Quality control of construction works - laser scanning can be used to verify whether the completed construction meets the design parameters and requirements. This can help detect errors in construction and address them in a timely manner.

3. Determining the volume of work and cost estimation - precise data obtained through laser scanning can be used to calculate the volume of work and estimate construction costs.

4. Monitoring the condition of buildings - laser scanning can be employed to monitor the condition of buildings and detect damages or deformations in their structure.

5. Creating virtual tours - accurate 3D models of buildings, created through laser scanning, can be used to create virtual tours of the buildings, which can be beneficial for tourism or educational purposes.

In summary, laser scanning is an important tool in construction that can help expedite the construction process, improve the quality of work, and reduce costs.

A scanner is a device that is used to obtain accurate data about the surface of an object. A scanner can be used in various fields such as medicine, engineering, architecture, and manufacturing. A scanner can obtain precise measurements of an object, including size, shape, and structure. Scanners come in different types including laser, optical, ultrasonic and others. Laser scanners are one of the most common types of scanners that use a laser beam to measure distances and create point clouds. Scanners can be used to generate accurate data that can be used to create 3D models of objects and buildings, quality control of construction work, scoping and costing, monitoring the condition of buildings, and creating virtual tours. One of the most common applications of scanners is laser scanning, which provides accurate data about the surface of an object using a laser beam

LIDAR aerial survey involves using airborne laser sensors to collect high-precision three-dimensional data of the Earth's surface. It differs from other remote sensing methods by providing detailed and accurate elevation information with exceptional vertical resolution.

LIDAR technology works by emitting laser pulses towards the Earth's surface and measuring the time it takes for the reflected light to return. It captures detailed elevation information, allowing for the precise mapping of terrain, vegetation, buildings, and other surface features with high accuracy.

LIDAR aerial survey is commonly utilized in applications such as topographic mapping, forestry, urban planning, and infrastructure development. It contributes to infrastructure planning by providing accurate and detailed information about the terrain, enabling engineers and planners to design projects with a thorough understanding of the landscape.

LIDAR aerial survey offers advantages in environmental monitoring by providing precise information on vegetation structure, land cover, and terrain characteristics. It supports the assessment of ecosystem health by aiding in the identification of changes in vegetation density, habitat mapping, and monitoring of landforms in various environmental contexts.

The integration of LIDAR data with GIS technology enhances the analysis and interpretation of aerial survey results by allowing for spatial analysis, visualization, and data integration. This integration provides a comprehensive platform for decision-makers to analyze elevation data in conjunction with other spatial information, supporting informed decision-making in diverse fields.