Well, What is it? Terrestrial laser scanning (TLS) is a form of measuring with a tripod-based LIDAR (light detection and ranging) instrument used to capture high accuracy data of buildings and other objects.
What is it used for?
TLS is used for a large variety of different applications, including capturing the flatness of a wall, preserve the conditions of a crime scene or accident, document the faꞔade of a large building for pre-fab architectural paneling, analyzing the shape of a vessel, volumetric stockpile surveys and many more.
How does it work?
Terrestrial Laser Scanners works by emitting an invisible laser to measure 3D points the same as a survey total station would. The difference is the scanner’s ability to measure its entire scene and the speed at which the measurements are taken.
The laser field of view is 310 degrees vertically and 360 degrees horizontally. The laser scanner will rotate upon the tripod and spin the mirror at the same time to capture the full scene. Each scan takes about 3-7 minutes, depending on the resolution.
What Does a Terrestrial Laser Scanner measure?
Terrestrial Laser Scanners measure everything in the line-of-sight of the laser. The smallest details like the texture of brick, the leaves on trees, and the metalwork of ornate hand-railings are picked up in the scans.
What is the accuracy of the Terrestrial laser scanner? Is it any better than a pro-3D camera?
Absolutely, terrestrial laser scanners can measure points as accurate as 3mm at 30 feet. A standard pro-3D camera cannot achieve less than an inch of accuracy. The resulting “point clouds” from the scanner are extremely high-resolution with points in spaced very close together, so close that the result of a scan looks just like a photograph.
The higher the resolution the slower the scanner will rotate making the resulting point cloud more detailed. The faster the scanner rotates the less time the laser has to document to small changes creating a lighter point cloud.
The Resolution of the scanner does not always directly affect the resolution of the “project point cloud”. For example, scanning a single wall with a handful of low resolution scans the resulting point cloud will be a higher resolution because of the number of points that accumulate from more than one low res scan.
Color or Black and White?
Depending on the need or conditions of the project, laser scanning can be conducted in absolutely no light. This makes it possible to measure and see things in places of absolute darkness. When scanning in dark conditions, the scanner is unable to pick up color unless artificial light is added, but the resulting point cloud imagery looks almost like night vision. Everything that was once very dark will be brightly visible in the 3D imaginary.
What are the benefits of using terrestrial laser scanning?
Benefits in Architecture
Capture the “as-is” conditions of a building quickly, accurately, and with little to no disruption. Photorealistic imaging and 3D visualization of different aspects of buildings to create views never seen before. 3D data can be used in all common CAD programs. FARO WebShare Cloud for sharing the scan data via the internet simple, secure, and can be used anywhere online. The resulting point clouds can be precisely modeled in Autodesk Revit.
Benefits in Construction
Laser Scanning in construction can offer fast and cost-effective documentation of the entire construction process. Seamless capture and monitoring is critical for construction progress for legal and technical documentation, precise dimensional check of complex components such as free-form shape elements, documentation of deformation processes and monitoring of countermeasures., project coordination to help improved multi-trade project collaboration. Capturing scans at all phases of construction can aid in the case of final building inspections by being able to go back and visualize the entire construction process start to finish.
Benefits in Property Management & Facility Maintenance
Building information models (BIM) is taken another step further here at PMI. We interject valuable asset information right into the living model. This way your facility can be on the cutting edge of maintenance and efficiency by utilizing autonomous features right through the model.