3D Laser Scanners Capture Minute Details
3D Laser Scanning Capacity
A 3D laser scanner has the capacity to document the entirety of a real-world object or environment down to the minutest of details. Laser scans act simultaneously as a camera and as a ruler, thus eliminating the need for photographic interpretation as well reducing the time required for physical measurements. Laser scans also support the creation of 3D models to within a fraction of a millimeter depending on the sensitivity of the instrument.
Litigation and Analysis Support
These scans also establish a baseline for analysis and litigation needs. Laser scanners recreate real-world objects and environments in electronic form by recording millions of points of three-dimensional laser distance data. The laser distance data are saved in a text file, referred to as a “point cloud”, as the x-y-z coordinates for each point measured. This point cloud file can then be processed, analyzed, or presented in a variety of ways.
Some examples of 3D scanning as a documentation tool include the following:
- Input to mechanical or structural engineering analysis tools
- Dimensional documentation when plans are non-existent or out of date
- Vehicle collision scenes
- Structural damage assessment due to fire or collapse
- Wildfire documentation
- Scope of damage assessment
- Identification of hidden or hard-to-detect damage
- Projectile paths after an explosion
- Evidence preservation for later use
- Model creation to demonstrate various cause hypotheses
3D Laser Scanning Examples
Storage Tank Fitness for Service
An existing six-million-gallon oil storage tank was suspected to be out of compliance with the requirements of the governing American Petroleum Institute construction code. An analysis of the tank was initiated to determine whether the tank was still fit for service, or if the tank needed to be rebuilt. A laser scanner was used to create a 3D digital copy of the tank structure. The scanned data were recorded to the square millimeter and input into engineering analysis software.
Based on the analysis, it was determined that the tank would be able to withstand the forces expected while in service. The scan was conducted as a single day’s effort, with a corresponding cost savings. The engineering analysis benefited from the improved accuracy and detail of the measurements obtained. The analysis results facilitated negotiations between the parties involved.
Vehicle Accident Reconstruction
For vehicle collisions, 3D laser scanning allows for measurement and documentation of damage to the vehicle(s) as well as conditions at the scene of the collision, such as road marks and fluid stains. The digitized data can then be imported into various software tools for a reconstruction of the collision. The results are also available for preparing and presenting an animation.
In this example, a tractor-trailer had rear-ended a passenger vehicle. At issue were the relative speeds at impact. 3D laser scans of both vehicles and of the collision site were used as input in reconstructing the collision. When engineering analysis is necessary to resolve a claim or litigation matter, a number of tools are used in tandem to help identify and document facts. 3D scanning is one such tool. As a technology, 3D laser scanning requires less time and offers greater accuracy.