Carl F. Thelin

RE – SEARCH and RESEARCH

            What is that hyphen doing there? Do you expect the word research to mean only one kind of activity, such as doing scientific experiments in the physical or chemical fields?

            I grew up in organizations that were designated as R & D organizations. Research and Development, whether for academe, industry, or government has facets of importance to all of us. General Motors, CALSPAN and the NHTSA have large expensive facilities and highly skilled people to do experimental research with cars and trucks. A physicist in those laboratories can seek new information by experimenting with tools so expensive that few individuals could afford them. Experimental research ought to be the last kind of research.

            Places with big labs also had other researchers -- the ones with the hyphen. The hyphenated word re-search suggests re=doing something again; search= looking for that something. A re-searcher is the person who searches libraries for references to the research done by other individuals and groups. This person looks into that history. We don’t want to waste time having our experimental researcher do something a second time. We avoid that if the first experiment was good enough – or not. Sometimes you could combine several researchers’ findings to reach a new conclusion. Library research should be the first kind of research.

            Now another kind of researcher goes into action in many cases. This combines experimental skills with knowledge from other sources to develop new understandings. This person was once as rare as Albert Einstein or Steven Hawking, who created elaborate models of the universe in their minds. Now scientists create accurate imaginary models with which to experiment in a laboratory that sits on the desk. The personal computer permits us to simulate events that we cannot otherwise examine. Realistic modeling of probable scenarios is the new kind of research. Today this saves time by zeroing in on the experiments (actual physical ones) that are most likely to be successful.

            Here is a way modeling is used in my field. There is a common highway collision that we call the "near-hit -- near-miss" scenario. An example is where the driver of a car is waiting at the stop sign of a cross street. He pulls onto the highway while turning left just in time to be hit by a truck coming from his left. In crash research, we gather as much information about the collision as is available. Then we experiment with scientifically validated computer programs that accurately model the scenario. These allow us to examine many possible outcomes given a range of assumptions in association with the known facts. We can experiment with variations in the appropriate speed of the vehicles, or with the frictional nature of the surfaces, or with the timing of the truck driver's reaction to the cross traffic or the car driver's response to visible threats. These computer simulations are dependent upon the skill of a teammate who gathers the physical data like the length and character of the tire marks. The computer model also needs data found by our re-searcher in various databases for numbers such as the mass and crash stiffness of vehicles. The personal experience of the researcher counts, too. He must apply his judgment and chose the most probable values of variables in the model.

            The role of the expert person who reconstructs an accident is to examine all the available evidence. Some eye witness descriptions will agree; others won't. The expert combines all the data and searches for the scenario that has the least contradictions. The ability to examine quickly and cheaply many combinations of distances, timing, and sight lines enable the experienced person to arrive at a reasonable conclusion and illustrate it so convincingly that others will share it. Using computers to produce realistic three dimensional visual images is the latest enhancement. Now the expert can use graphical output to compare each result of his experiments. Then he can display his conclusion pictorially so that even a layperson will agree that is what most likely happened.

            Back to the example. Experimental data is needed. We could measure the rate at which the truck would coast down if the driver were to lift this foot from the throttle pedal. This would vary with the grade of the road as well as with the engine size and transmission ratio. We have the means of getting a continuous plot of speed and location of the automobile as it accelerates and turns left, depending upon the radius of the turn and the power of the car's engine. Some judgment must be used, since it is unlikely that anyone would make such a maneuver at full throttle. Then we must find appropriate values for the coefficient of friction, if the truck driver was able to get onto the brakes before the collision. If the collision occurred at night, we must consider the effects of the truck's headlights; if they were on high beam, the additional glare might prevent the driver of the car from seeing the truck's top mounted clearance lights and recognizing that the oncoming headlight spacing was narrow because they were on a truck, and not a far away passenger car.

            All these things can be stirred into the mixture for examination and simulation. If we calculate that the driver of the truck was traveling well above the speed limit, we can ask this question: If the driver of the truck had been going at the speed limit, would the car have safely completed it turn before the truck reached the point of the collision? Or, we may find that the driver of the car waited too long, and pulled into the path of the truck when there was no time remaining for the truck driver to avoid the collision.

            The synergism of a large forensic engineering firm enables them to utilize all three kinds of research to develop sound analyses and clear presentations for an investigation.

            By the way, I used to tell the guys this:

“It’s OK to make mistakes. It is even OK to make the same mistake twice, just in case you think you did not follow your own plans correctly the first time. Making the same mistake three times is dumb. So, keep making new mistakes until you find what is left is the right thing to do.

Then quit.”