Benefits of Using Scanning Technology in Forensic Testing
On the Scene E-Newsletter, Edition 105, December 1, 2009
Most recently, many engineers have turned to object scanning technology opposed to traditional methods during an accident/incident investigation in litigation cases due to speed, accuracy and the ability to return to the data days or even years after the original evidence has been destroyed.
What is scanning technology? Originally designed for assisting surgeons in finding precision locations during surgery, this highly accurate device enables CED engineers to precisely document vehicles and component parts with specific applications in automotive, aerospace, water vessel and industrial environments with a high degree of measurement validity and reliability.
With the aid of Computer-Aided Manufacturing Measurement software, CED
utilizes the scanner to reverse engineer both simple parts and complex components. The resultant scanned images are assembled into 3-dimensional electronic Computer-Aided Design (CAD) models specific to the actual product under engineering investigation.
Examples of how CED uses the equipment to serve clients includes:
Vehicles – (cars/trucks/tractors/trailers/boats/components/etc.)
The traditional method of collecting vehicle crush measurements are time consuming with hand written coordinates or measurements generated using a tape measure and documented with photographs. These notes are then given to someone to create an engineering drawing.
However, with a portable scanning device an engineer can measure the entire vehicle in as little as 2-3 hours depending on the amount of deformation. But the huge time saver is that as the data points are selected, the computer software builds a surface model in real time. The engineer walks away with a 3D computer model. The model can then be used to (1) measure the amount of crush deformation, (2) be analyzed by biomechanical engineers for passenger biokinematics or (3) loaded into computer crash simulation or animation software.
To avoid liability, manufacturers should ensure their products are properly designed and manufactured to avoid injury. The scanner can be used to identify hazards or after an incident, to accurately measure and document a component exemplar for comparison to the component artifact. The scanner can assist CED engineers in finding the cause and origin of a failure and also gives them data they can use to offer the client possible design change options.
Design or Testing Capabilities
Another scanner application is reverse engineering which allows engineers to take a physical object and create an exact digital replica. The digital file created by the scanner can be used for non-destructive testing and analysis (including structural analysis, fluid dynamics testing and finite element analysis) or for reproducing valuable design information for items where no full or accurate documentation exists.
These are only a few examples of how digital scanning enhances forensic engineering inspections. The scanner offers speed and superior data quality for documentation. It does not replace an accident/incident investigation – it complements the investigation.