This mornings highlight: 3D Documentation and laser scanning in Law Enforcement.
David Dustin, a US forensic expert from Dustin production presented this morning in the Andechs Abbey the usage of 3D laser scanning for many kinds of law enforcement applications. Amazing presentation!
Laser scanning is rapidly gaining acceptance and becoming more and more commonplace in the law enforcement and accident reconstruction communities. Over the past few years, hardware and software have improved significantly creating a simpler, overall system to capture immense detail in a short period of time.
These are 10, of the many, reasons to consider laser scanners for a forensic application:
1) Easy to use: Many manufacturers are moving toward a simpler interface making operation of the scanner more like a digital camera than a complicated survey instrument.
2) Portability: Laser scanners are smaller in size today than ever before making them easier to deploy to a crime/accident scene and useable by just about anyone.
3) Safety: Data can be collected from a distance, with some scanners collected measurements over 300 meters away. This allows the operator to scan a scene out of harms way. In addition, laser scanners can collect up to 1,000,000 points per second with average scan times of several minutes. Less time on a scene means less time for potential danger to the individuals at the scene. Class I lasers are also being used in laser scanners creating a truly eye-safe environment during the scan.
4) Speed and Efficiency: Complete color scans can be captured in as little as several minutes creating a virtual scene with high accuracy and detail that can be revisited over and over without physically traveling to the site. In contrast to traditional methods of surveying/documenting a scene, laser scanning can be much faster and allow multiple investigators to have eyes on the virtual scene.
5) Produce a variety of deliverables: Once the scene has been laser scanned, various types of final products can be extracted or produced from the data. For example, anything from a traditional 2D drawing to a detailed 3D animation can be created from the scan data.
6) Peer pressure: With more and more agencies utilizing laser scanners for their scene documentation, the result is more widely accepted. As well as growth in expectations that future scenes will be documented in 3D.
7) Cost Effective: Laser scanners are becoming more and comparable in price to total stations which are traditionally used for documenting traffic accidents.
8) Specialized Measurement Tools: Software for forensic analysis from 3D data also now includes special tools for measuring blood spatter and bullet trajectory, witness/suspect height, etc.
9) Easy to share: More software tools are available to view and document the scan data without the requirement of installing software or purchasing additional licenses.
10) Archive the scene: Once the scene has been laser scanned it has been essentially frozen in time, preserved for future virtual visits by anyone who may wish to investigate the scene. This allows for measurements to be taken that may not have necessarily been thought to be important at the time of capture as well.
Blog post by Alex Demogines, Account Manager Laser Scanner, FARO Technologies
While new technologies are used to entertain viewers of TV crime series, the real Crime Scene Investigators are hard at work, pushing the boundaries of forensic science, documenting cases, and baselining real-world events.
This is the job of Michal Frydrýn and his colleagues at the Department of Forensic Experts in Transportation (DFET) at the Czech Technical University (CTU) in Prague. Serving the country’s police departments or its courts, the team uses their expertise to analyse road traffic accidents. They visit the site, document the scene and submit a forensic report.
“The requirement for these reports drives our own baseline research, explained Michal. Recently, we examined the passive safety of cars specifically in relation to the protection of child pedestrians. It is a long term project that actually took us three years: we created a specialized forensic laboratory on university premises, fitted it out with appropriate equipment, including traditional measuring tools and suitable anthropomorphic test devices (crash test dummies) and then ran a programme of testing and evaluation.”
Michal explained that for the final year of the project, the DFET employed a FARO Laser Scanner Focus 3D: “The arrival of the FARO scanner means we won a substantial improvement in our baseline data and 3D documentation.”
Within the carefully controlled laboratory environment, we accelerated a Skoda car to speeds of 10, 20 and 30kph and allowed it to strike a P6 crash test dummy. The dummy was designed to impact the car in the manner of a child and to record the effects on a child’s body. With the Focus 3D, we were able to record the whole scene and create highly detailed documentation of the deformation of the car – especially the bonnet. Using the FARO, we secured more information on the position of objects at the crash site, and more detail on the deformation of the vehicle, than was possible with the laser scanning equipment we had used previously. This increase in detail has served to add new depth to our documentation.”
As a result, this fundamental baseline data allows DETF to examine the bonnets of similar vehicles after real accidents and to determine the speed the vehicle was travelling at the time of collision with the child. Michal re-enforces this final point: ”At the accident site itself, the Focus 3D allows us to quickly document the scene with generous 3D detail to aid in the analysis, enabling our delivery of reliable, timely evidence to the courts”.