3D Laser Scanning

29.08.2020

3D Laser Scanning

There are different types of laser scanners, but they all work the same way. The laser scanner is a technically complex device, but the control of the shooting process is arranged simply for the operator. The scanner generates a constant or high-frequency pulsed laser beam, while the device itself automatically rotates around its axis, while a rotating or oscillating mirror positions the beam in a vertical plane, as a result, the beam covers the entire space around the scanner. When the beam hits an object, part of its energy returns back to the scanner and the device fixes it. The arrival time of the signal is used to calculate the distance from the scanner to the object. However, in a laser scanner there is not only a laser rangefinder, for each measured distance, other measurement information is also recorded – the horizontal angle of rotation of the scanner and the vertical angle of rotation of the mirror. The scanner automatically combines all measurement information and calculates the x; y; z coordinate for each measured point, so the resulting scan is a set of x; y; z measurements. This is a detailed three-dimensional representation of the surrounding area, commonly referred to as a billion-point cloud of points, in order to add real point colors to the scan, panoramic images can be taken with the cameras built into the scanner. Using the built-in cameras, you can automatically match photo data with scan data.

Laser scanning is a method of high-precision digitization of structures, parts, mechanisms, terrain mapping or its digitization, however, unlike technologies that allow sequential survey of individual points, laser scanning allows you to quickly obtain detailed measurement data about the entire object as a whole. It’s like the camera is taking a 360 ° panoramic photo, but it still gets the exact 3D coordinates of each pixel. This is one of the main advantages of obtaining high-quality executive survey or measurement information about the current state of the object.

No other method can give such a complete picture of the object. At the same time, we work not just with an image, but with a model that preserves full geometric correspondence to the shapes and sizes of a real object. This provides the ability to measure the real distances between any points or elements of the model.

The survey is so complete and detailed that whenever you access data sets, it is as if you are returning to the field to find any data or supplement the project. Plus, you shoot faster. The control is much more complete. Scan data is measurement information, and you can use it in programs for various types of tasks. For example, using virtual data, you can analyze the real position of the structure relative to the design one, calibrate tanks, etc.

Laser scanning technology works as follows:

The first is the field stage – the scanner captures objects.

The second is office processing, where field data is converted into the results you want. In the field, you simply put the scanner in the optimal position for shooting an object, press a button and wait for the scanner to do its job. At the field stage, if necessary, you can take panoramic images of the object and make the data even more realistic. To obtain a survey of the entire object, scanning is performed from different points and several scans are obtained, which are then stitched and snapped to the coordinate system during scanning or later. The scanned data can be precisely referenced to the desired coordinate system, just like a standard topographic survey. Data processing software allows users to create an infinite number of final designs, ranging from the most basic results such as 2D plans and elevations, clear and convenient panoramic images with the ability to obtain measurement information for each pixel, dimensions, measurements between points, points and surface, high and low elevations of nodal points, sections and profiles, measurement of volumes. In addition, scanning technology provides additional results such as detailed topographic plans, triangulated spline surfaces, information asset links, fully textured models, overviews, intelligent 3D industrial models, and BIM – building information models. It all depends on the software.

Applications for 3D Laser Scanning

Construction and operation of engineering structures:

  • control over the compliance of the geometric parameters of newly built objects and design documentation for these objects;
  • adjustment of the project during construction;
  • executive shooting during construction and after its completion;
  • optimal planning and control of the movement and installation of structures and equipment;
  • monitoring of changes in geometric parameters of operated structures and industrial installations;
  • updating of the general plan and reconstruction of the lost construction documentation of the existing object.

Mining industry:

  • determination of volumes of workings and warehouses of bulk materials;
  • creation of digital models of open pits and underground workings for the purpose of their monitoring (data on the intensity of the reflected signal and real color allow creating geological models);
  • mine surveying (volumetric measurements) support of drilling and blasting operations.

Oil and gas industry:

  • creation of digital models of industrial and complex technological objects and equipment for the purpose of their reconstruction and monitoring;
  • calibration of oil-loading shore and tankers tanks.  

Architecture:

  • creation of architectural drawings of building facades;
  • restoration, repair, decoration, re-equipment of internal premises or individual decorative elements.

Other areas:

  • development of measures to prevent and eliminate the consequences of emergencies;
  • performing topographic survey of areas with a high degree of development;
  • shipbuilding;
  • modeling of various types;
  • creation of two-dimensional and three-dimensional geoinformation systems for enterprise management.