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About this Article
Written by: Scott Franke
Written on: April 1st, 2000
Tags: civil engineering, transportation, lifestyle
Thumbnail by: U.S. Department of Transportation
About the Author
At the time of writing, Scott Franke was a senior at the University of Southern Californa, pursuing his Bachelors degree in Computer Science.
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Volume I Issue IV > Intelligent Transportation Systems
Personal transportation is truly a marvel of the twentieth century. Advances in many fields of technology have made automobiles and channels of transportation available to almost anyone. However, the freeways in major cities, on which so many people depend on to get them to work or school every day, were not designed for the amount of traffic they are now required to accommodate. Because of this, there are many problems with heavy traffic, and we experience difficulty in quickly responding to problems that occur. A national program called Intelligent Transportation System (ITS) attempts to solve these problems through engineering and technology.

The Problems

Even with the technology embedded in today's automobiles, driving can be a frustrating and potentially deadly experience. This is especially true in large metropolitan cities, where the criss-crossing network of highways creates an amazingly complex system, just waiting for something to go wrong. And things will go wrong, there's no avoiding that, the system depends on far too many elements. However, there are still things that can be done to minimize the risk and effect of the occurrences. Generally the solution for reducing traffic has been to widen highways. However, this merely postpones the problem; the number of people and cars on freeways will continue to increase. A national program called Intelligent Transportation System (ITS) attempts to solve these problems through engineering and technology. ITS achieves this by combining the hardware, software, and networking necessary to gather, process, and distribute information important to the parties involved.

Goals of ITS

The official goals of all ITS organizations are to improve the safety and efficiency of traveling on city freeways. These are serious issues and have an effect on citizens of large cities on a daily basis. When there is an accident on the road, the response time of medical services is extremely important. Seconds can make the difference between life and death; Emergency Medical Services (EMS) needs to be on the scene right after the accident has occurred. If the system is integrated into the transportation infrastructure so that EMS is alerted within seconds of a traffic accident, many lives can be saved.
U.S. Department of Transportation
Figure​ 1: Vehicle to vehicle communications could help prevent crashes on freeways.
The next step to make transportation safer is to reduce the risks than can cause such accidents. This includes reducing traffic congestion, clearing accidents more quickly, and routinely checking the transportation channels for dangerous areas or obstructions (see Fig. 1). The problem is that it would require a massive workforce to successfully implement this sort of program in a major city like Los Angeles.
Luckily, there is a better solution. ITS proposes to work towards solving these problems through the application of technology. ITS does this by combining sensors to gather important information about traffic and accidents, a data network to transfer that information, and a base of operations with mainframe computers to process and distribute this information. This network of sensors and computers can provide instant and comprehensible access to a large set of complicated data [1].

Structure of ITS Gathering Information

To understand how an ITS system would operate, it is helpful to look at how all the parts work together. First, there is the information gathering stage. Here, many cameras and sensors around the whole city study and collect data 24 hours a day.This data can be visual or infrared images of traffic, or electronic sensors that measure traffic speed and density.
It is important for the computers and engineers studying the data that the visual images be not only clear and crisp, but that the visual coverage of the freeway is as complete as possible. If an accident happens on a part of the road that is not visible, the whole system is pretty much useless. Infrared cameras can provide information that a conventional visible light camera might miss, however they also require different processing than regular cameras.
Besides cameras, loop detectors can be used to determine traffic flow and density. These are loops of metal wire under the road; a small computer monitors the change in inductance in the loop caused by the magnetic field of a metal object (in this case a car) passing by. By measuring the time it takes for each car to pass by and the number of cars that pass by in a given amount of time, a computer can determine the average speed and density of traffic on the road. However, these computers cannot perform a useful function without the data from the sensors [2].