The overall science and art of crash reconstruction has not changed significantly over the years. What has changed, and is constantly changing is the technology of motor vehicles, the transportation system and the tools with which to gather evidence.
One of the most significant advances is the proliferation of sensor technology including on-board event data recorders (sometimes known as black boxes). More passenger and commercial vehicles are being equipped with electronic control modules that can provide extremely valuable electronic data to compliment roadway and other evidence. We currently have the ability to download data from select General Motors, Ford, Isuzu, Hummer and other passenger cars, light trucks and vans. We also have the capability to download data from Detroit Diesel Engines for commercial vehicles. Not all vehicles are equipped with such recorders and not every crash may actually 'wake up' the sensors. However, you can be confident that we will make every effort to determine whether such data exists and download the data according to current court rules and laws. Over the years, we have successfully downloaded electronic data and have realized the dramatic leap forward this technology is providing to the total reconstruction. Although electronic data alone can not answer all questions, when included in a standard reconstruction, this category of evidence provides a quantum leap forward in the accuracy of an analysis. 
Over the past 10 years we have utilized the dramatic improvement in scene measurement capability provided by forensic total station technology. These electronic distance measuring instruments have become invaluable for measuring intersections, highways, crime scenes, complex roadway evidence and topographic features. When accuracy counts, the older methods of using steel tapes and roller tapes may not provide adequate precision. When two experts use the same scientific approach and are looking at the same data, the one with the most accurate measurements has the greatest likelihood of being correct. Complex roadway geometry and topography in most cases can not be measured accurately with traditional tools. We have three total stations so that we can put three crews in the field at the same time, all of which can apply this important technology to their work.
One of the most important parts of calculating speed usually entails determining the roadway friction. In the 1950's and 60's, friction charts were developed from various universiteis such as Northwestern Traffic Institute. When these charts were developed it was before the onset of anti-lock brakes, radial tires, improved roadway materials and modern tire compounds. Furthermore, the charts were not developed for use with motorcycle or commerical tires. Although the charts still have their place in a reconstruction, we find it preferable to conduct tests skids. If the roadway has not changed, and such tests can be conducted safely, we will conduct tests skids with an exemplar vehicle using accelerometers from Vericom Corportation (VC2000 and VC3000) to measure roadway friction. Over the years we have conducted hundreds of tests skids throughout the United States and Canada and have a large data base to utilize along with the traditional friction charts. With a properly conducted set of test skids vehicle speeds and stopping distances can be more accurately calculated.
Some scale drawings can still be drawn with reasonable accuracy and legibility using standard drafting tools. However, over the years computer assisted drafting (CAD) has become the preferred method of generating accurate and flexible scale drawings. Introtech utilizes sophisticated CAD drawing programs along with color printer plotters to generate scale drawings for our analysis, as well as effective court exhibits.
We have an arsenal of other instruments that we utilize as necessary for our investigations including:
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Gas chromatographny for chemical analysis
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Sound and light meters
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Computer simulation software for testing certain types of crash opinions
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Reaction testing equipment
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K-55 Radars and laser speed measuring devices for conducting speed and traffic surveys
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Global Positioning Systems and chartplotters for motor vehicles and boats
We are dedicated to keeping current with motor vehicle technology and one member of our staff has the collateral assignment of continually researching new vehicle trends and capabilities. We conduct our own in-house training each year such as commercial vehicle anti-lock brakes, electronic stability control, global positioning systems just to name a few. In addition, we attend yearly training outside of our office on motor vehicle technology. Most recently our staff has attended updated training in the collection and interpretation of electronic data from event data recorders. By keeping current with the new tools and transportation system technology, we are confident that our analysis is as complete and thorough as time, budget and available data allow.
Last updated: 11/10/2006