The Intelligent Transportation System (ITS) is a program sponsored by the U.S. Department of Transportation (DOT). It was authorized in the Intermodal Surface Transportation Efficiency Act of 1991 and reauthorized in 1998 by the Transportation Efficiency Act for the 21st Century (TEA-21).
This program's overall objective is to apply information and control technologies to help solve transportation problems. More specific goals include increased transportation efficiency, greater safety, energy savings, and improved environmental quality. The program is designed to exploit the use of advanced computer, communications, and sensor technology to improve travel on highways and via mass transit. The DOT sponsors hundreds of projects to research, develop, test, and deploy new technologies and systems to meet these objectives. In November, U.S. Transportation Secretary Rodney E. Slater announced $93.9 million in grants to 41 states and the District of Columbia for new ITS efforts.
The ITS has laid out a set of goals and guidelines for use by states and local communities in developing a transportation infrastructure and for automotive manufacturers to follow in developing intelligent automobiles compatible with the smart highways. Other countries, notably Japan and European countries, have established ITS programs with similar objectives.
Simply improving traffic conditions in urban and suburban areas takes top priority in the ITS. Traffic is getting worse everywhere, especially in the larger cities. Trip lengths are longer, increasing travel time. Traffic jams occur more frequently, as do traffic accidents causing personal injury and property damage. Traffic congestion is primarily due to an increase in the amount of traffic at a far greater rate than the construction of new roads.
The DOT reports that the number of vehicle miles traveled in the U.S. nearly tripled between 1960 and 1991 while the U.S. population only increased by 40%. A scary prospect is that most local communities feel that road construction will never catch up with the traffic load. Financial constraints, political issues, and environmental impact studies slow and in some cases actually prevent new road construction. In general, traffic is going to get worse before it gets better. The goal of the ITS is to use technology to help increase the capacity of existing roads.
While the primary objective of the ITS is to improve traffic flow, the system can significantly reduce emissions, too. Eliminating the need to stop and start the vehicle or to idle at red lights or toll booths has an enormous impact on the amount of pollution generated. Some tests illustrate how improved traffic signals and automatic toll collection can decrease emissions as well as reduce fuel consumption by as much as 14%.
In collaboration with ITS programs in other countries, the DOT has helped define a group of user services that have been standardized by the International Standards Organization (ISO). These are divided into eight major categories:
- Automated Traveler Information Systems (ATIS): The objective is to provide as much information as possible about traffic and road conditions to help drivers plan the fastest and most efficient routes. Pretrip information would be made available by phone or computer link at home or the office. Additional information can be obtained during the trip through digital radio or cell phone. These systems also include an on-board navigational system. By combining GPS and route maps, drivers can receive information on a screen about their location to minimize the possibility of getting lost or taking a clogged or inefficient route.
- Automated Traffic Management Systems (ATMS): This part of the infrastructure is designed to optimize traffic flow and reduce traffic congestion by sensing traffic conditions through sensors and video monitors. An ATMS takes the information that it gathers and provides adaptive traffic signal control, ramp metering, and updated traffic message signs. In addition to the traffic signs, a radio-based in-vehicle system would be available to provide further information about weather and road conditions, depending upon the driver's location. The ATMS assumes the presence of some central monitoring and control facility where all of the related information is analyzed, updated, and communicated.
- Automated Vehicle Control Systems (AVCS): A long-term and perhaps even idealistic objective of ITS, AVCS would allow the autonomous operation and/or remote control of the vehicle. In these systems, the driver is partially taken out of the driving loop. Such a system includes vision enhancement and distance-warning systems using short-range radar, IR, or video, which would be tied to an adaptive cruise control to adjust vehicle speed and/or the brakes. The distance-measuring systems would produce either a warning to the driver or it might automatically handle vehicle speeds by engine or brake control. AVCS could also include other measures, like automatic steering, that use sensors embedded in the road for collision avoidance and safety.
- Commercial Vehicle Operations (CVO): This facilitates interstate trucking. CVO provides for electronic systems to deal with clearance paperwork, automated safety inspections, weighing trucks at highway speeds, and monitoring operations to improve safety, fuel efficiency, and emissions. Far more development has already taken place in the CVO area than any of the others in the ITS program. Trucking companies have developed and used navigation and truck tracking and monitoring systems by satellite and other wireless systems for many years.
- Automated Public Transport Systems (APTS): This part of the ITS program relates to public transportation systems involving buses, light rail, and the like. These systems provide route information to users as well as the monitoring and tracking of the various vehicles. APTS will provide a way to monitor ridership and enhance the safety of public transportation too.
- Emergency Management: The whole purpose of this segment of the ITS is to ensure rapid notification of accidents for prompt response to wrecks, vehicle breakdowns, hazardous-material spills, and other emergencies.
- Electronic Payment: Becoming more common, these facilities automate payments for tolls, parking, entrance, or fees. Such payments stop or slow down traffic more and more each year. Automated payment systems use RFID to permit automated payment through subscriptions and smart cards.
- Safety: Most of the other systems help ensure the safety of drivers. Additional safety systems primarily improve safety for pedestrians. This can be accomplished by providing systems for drivers to detect and avoid pedestrians, by controlling walk-signal duration to minimize pedestrian accidents, and by implementing systems to more efficiently deal with handicapped and elderly persons.