Intelligent highways: eight ways to increase your street smarts
As the potential for technology-driven highways revs up, transportation operators are using advanced computer technology and communication systems to manage complex traffic problems.
“Left my job about 5 o’clock … took me 15 minutes to go three blocks … with the freeway looking like a parking lot … Damn this traffic jam … “
— James Taylor
Drivers and passengers lose two billion hours each year to nerve-wracking traffic jams caused by an estimated annual increase of 20 percent to 30 percent in the number of vehicles clogging the highways. Every year, according to the General Accounting Office (GAO), it costs the nation approximately $100 billion in traffic delays, and an additional $70 billion per year is spent on traffic accidents.
Also, idling cars clog the air with nitrogen oxides, hydrocarbons and carbon monoxide, wasting approximately two billion gallons of fuel annually. As a result, clean air laws began placing increased pressure on local and state officials to use Transportation Control Measures (TCMs).
In 1991, Congress gave the green light to the Intermodal Surface Transportation Efficiency Act (ISTEA), a legislative outgrowth of the Strategic Highway Research Program (SHRP) — the five-year, $150 million research program created in 1987 to improve performance and durability of the nation’s highways.
The act helped stimulate broad-scale testing and helped recognize the potential of technology-driven highways, which in turn resulted in the development of Intelligent Transportation Systems (ITS) — advanced systems that create “interactive highways” — helping get drivers and their goods to destinations more quickly and cost effectively.
The technology, formerly known as Intelligent Vehicle Highway Systems (IVHS), enables transportation system operators to use advanced computer technology and communication systems to manage, on a real-time basis, complex traffic problems. The systems allow operators to minimize the disruption of traffic during long-term, planned transportation improvements and help appropriate agencies respond quickly to accidents and breakdowns.
“On average, ITS costs start at $50,000 per lane mile, compared to new construction of $1 million per lane mile,” says Richard Ridings, vice president of HNTB, Kansas City, Mo., and president-elect of the Texas Public Works Association. “ITS can increase capacity up to 20 percent without roadway expansion. High technology now offers a feasible solution for equipping America’s highways to accommodate heavy traffic.”
Using technology to solve problems is wiser than debating a “six-lane versus a 12-lane highway,” says Lois Walker, an Alexandria, Va., city council member. “By the time it would be built, even the 12-lane is obsolete.”
With road construction costs in metropolitan areas approaching $40 million per lane mile, technology is increasingly the most cost-effective tool for transportation management, according to Christine Johnson, director of the U.S. Department of Transportation (DOT) ITS Joint Program Office. She says local governments should scrutinize their technological purchases to ensure the capability for integrating services now and in the future.
By relying on “more creative use of technology,” says DOT Secretary Federico Pena, it is possible to address challenges encountered at the local level. Speaking at a special focus group of elected and appointed officials from cities and counties across the country, Pena stated that his vision for the 21st century is one employing “smart technologies,” such as electronic collection of tolls to eliminate traffic bottlenecks and automated traffic signals to reduce commuting time.
Following are eight ways various smart technologies are being applied to traffic management throughout the country.
1. Interactive Highways. “Interactive highways are a means of communication between the road and driver that warn of approaching road conditions,” Ridings says. “ITS components include Automated Vehicle Control (AVC) systems, Electronic Toll and Traffic Management (ETTM) systems, Advanced Traffic Management Systems (ATMS) and Advanced Traveler Information Systems (ATIS). `Warnings’ include electronic message boards that suggest alternate routes to approaching motorists, designated radio frequencies that give updated traffic reports and computers in vehicles that display approaching traffic conditions.”
Hampton Roads, Va., implemented an incident management system that detects abrupt changes in vehicle speed. The three-and-one-half-mile approach to the Monitor/Merrimac Tunnel is lined with passive vehicle detection devices that determine the speed of vehicles passing through detection points. When the system detects slowing traffic, motorists are alerted to take alternate routes.
And in locations like Osburn, Idaho, drivers are alerted to accidents, bad weather and snow removal with a series of IVHS sign systems, like the full matrix pixel display installed at Lookout Pass by the Idaho Transportation Department in 1993.
Message signs like those manufactured by American Electronic Sign, Spokane, Wash., are designed to allow operators a choice of one-, two- or three-line messages. Because the signs are backlit, the sign message is not eradicated by light coming from behind the driver.
Remote programming capabilities and diagnostic features allow the Idaho DOT to immediately alert travelers to emergency situations so they can take alternate routes to avoid delays.
The diagnostic features allow for remote testing of the pixels to determine if they are working properly. The actual message on the screen can also be seen.
2. Emergency Signal Priority. “Minutes in an emergency response may be the difference between life and death,” says Claud Lacey, business development manager in the Safety and Security Systems Division in 3M’s Traffic and Personal Safety Products Group, St. Paul, Minn. “This is why it is important that emergency vehicles and their crews have a way to quickly get through congested areas.”
The Opticom priority control system enables a vehicle equipped with a system emitter mounted on the vehicle to send a coded infrared message to the system detector, installed at the traffic intersection.
When activated, the detector receives the coded message and converts it to an electronic impulse, which is then sent to the system phase selector in the intersection controller cabinet.
The phase selector requests the controller to either hold the existing green light until the vehicle passes through or to cycle from the existing red light to a green light.
Public safety personnel — police, fire and abulance teams responding to 911 emergency calls — are able to easily activate the system with a simple flip of the switch.
3. Electronic Tolls. Electronic Toll and Traffic Management (ETTM) systems are being used on State Route 91 (SR-91), which connects California’s Orange and Riverside counties. The road will feature a 100 percent Automatic Vehicle Identification (AVI)-based ETTM system.
Developed by MFS Network Technologies, Oakbrook, Ill., the system encompasses the Texas Instruments Registration and Identification System (TIRIS) that will serve as the foundation for implementation of broader Intelligent Vehicle Highway Systems (IVHS) applications.
The AVI subsystem identifies a vehicle via a TIRIS radio frequency transponder manufactured by Texas Instruments, Dallas. Placed on a dashboard or attached to a license plate, the transponder carries a unique programmable identification code.
As drivers pass by a TIRIS radio frequency reader located in a designated toll collection area, the system automatically assesses the appropriate charge to either a pre- or post-payment user account maintained on toll agency computers.
The ability to pay tolls without stopping helps eliminate increased air pollution and energy/fuel consumption resulting from idling engines. Other benefits of the system include the ability to alleviate traffic congestion and minimize commute time.
The system’s capabilities include a video enhancement system that captures a video image of violating vehicles’ license plates; a fiber optic communication network linking all video, voice and data subsystems; variable message signs to advise motorists of highway conditions; and a mobile communication system linking toll road operations to the California Highway Patrol and CALTRANS.
4. Graphic Information Systems Capabilities (GIS). Atlanta currently is preparing for the imminent presence of two million spectators, athletes and dignitaries during the 1996 Olympic Games by incorporating an automated, interactive and information-rich transportation network.
Software created by Graphic Data Systems (GDS), Denver, has been selected to provide real-time mapping and graphic information systems (GIS) capabilities for the Atlanta Regional Advanced Traffic Management System (ATMS). The software will be an integral component in managing traffic congestion and travel inquiries during the Games.
Working in cooperation with the Georgia Department of Transportation (GDOT), the company will build a digital base map of the ATMS service area that will be used by the agency to satisfy its map-based information needs.
An object-based software system used for transportation mapping and management, it will provide a real-time dynamic display of road conditions measured by field detection devices and a digital map of public transportation routes and favorite tourist locations.
The ATMS service area will include more than 60 miles of freeway and 25 miles of High Occupancy Vehicle (HOV) lanes, managing traffic flow in five counties and metropolitan Atlanta.
“In the past, we would expand our highways when traffic congestion sky-rocketed,” says Eric Wood, GDOT transportation engineer. “With the ATMS, we have the ability instead to better manage what we’ve got for the Olympic Games and beyond.”
As part of the ATMS initiative, numerous field detection devices have been installed to monitor traffic, and others will be installed during the months preceding the Olympics.
For example, an AutoScope video detection system using 494 closed-circuit TVs (CCTV) will record lane-by-lane occupancy, volume and speed.
Ramp meters will be installed at the entrance of five major on-ramps to analyze the amount of traffic entering the highway, and 41 changeable message signs will transmit suggestions of alternate routes, accidents, construction and delays in traffic.
At GDOT, data transmitted from field detection devices will be integrated with the software and displayed as real-time, color-coded traffic information on operator consoles and on a computerized, large-screen map.
This map shows the roadway network, locations of various detection devices and the traffic conditions monitored by the devices. The detectors will measure specific factors and feed the information into the system.
As data flows into the system, road conditions will change on screen as they happen. For instance, a smoothly flowing highway will be depicted by green highway segments.
Slower moving traffic segments would be shown in yellow, stopped traffic in red.
The software’s capabilities make it possible to show, in real-time, only those segments of the road where conditions have changed or an accident has occurred. Without repainting the screen, traffic personnel have more time to respond to immediate situations on the roadway network.
They can literally “see” traffic congestion problems as they happen, offering a more dynamic and flexible display and analysis environment.
As a result, personnel will be able to anticipate traffic delays, activate message signs to divert traffic and dispatch response vehicles in a timely manner.
“We’re running out of room here,” Wood says. “But with this type of technology, we can continue to improve the traffic situation without rebuilding.”
5. Speed Cameras. Two Utah cities have taken bold steps to put a stop to traffic accidents by incorporating speed cameras to creack down on speeders. Analyzing steadily increasing traffic accidents and deaths in West Valley City and Sandy City showed that a majority involved one or more vehicles traveling in excess of posted speed limits.
“A look at national and international studies of traffic accidents revealed that the faster the vehicle was traveling, at impact, the more serious the resulting damage or injury,” says Cheryl Walsh, director of communications, American Traffic Systems, Scottsdale. “City officials determined that if they could control speed, they could begin to get a handle on accidents.”
The technology helped West Valley City traffic accidents decrease from more than 3,000 in 1990 to less than 2,200 in 1991.
“Recently, we used a speed camera on a two-lane road and wrote 80 citations in four hours,” says Sandy City Chief of Police Sam Dawson. “Four weeks later, we used it in the same spot and didn’t have one violation.”
Despite some initial criticism of the speed cameras, the users of the services now are quick to praise it.
The system’s benefits include freeing up police officers for more serious crime prevention, placing the cost of the program on the violator instead of the taxpayers, enforcing traffic laws without discrimination and having the potential to lower insurance costs.
The speed cameras, which are available in portable or fixed-site models, feature precision speed measurement with a sensor array consisting of a conventional inductive loop positioned between two sensors, pre-scheduled operating modes, extended operation and a traffic data logging system for each vehicle.
Under similar setups in Paradise Valley, Ariz.; Riverside, Calif.; and various Florida cities, the cameras are provided to the police department and placed at chosen locations.
The film is then developed, and through a link with the motor vehicles department, citations and second notices are then issued through outside contractors.
The data includes location, date, time, lane number, direction, speed, image control number, frame sequence number, vehicle type, length and number of axles.
6. Seamless Management Across State Borders. The Ohio Department of Transportation, the Kentucky Transportation Cabinet and TRW, San Diego, are joining forces to develop one of the first traffic management systems in the United States to provide seamless freeway and expressway management across state borders.
Beginning, in November 1996, approximately 88 miles of interstate freeways will be monitored and managed by an “intelligent” control center. Using roadway detectors and roadside cameras, a traffic operations center will receive and process traffic flow data.
The operation center will then communicate with motorists using highway message signs and radio advisories to warn of upcoming congestion and suggest alternate routes. The operation center will instantaneously respond to traffic incidents, coordinating with emergency management agencies that dispatch emergency vehicles.
Once the system is in place, it is expected to provide annual cost savings to both states of $15.9 million in reduced traffic delays, accidents and fuel consumption. Five counties are involved in the project: Hamilton and Clermont in Ohio, and Kenton, Boone and Campbell in Kentucky.
7. Work Zone Safety. Reducing DOT injuries and deaths in highway work zones has long been a concern; now it is becoming a reality. New developments in radar detecting technology are helping to alert drivers of work zones and other types of radar hazards.
Various intrusion alarm and radar emulator products are currently being used in test studies around the country. One such product, the Myriad Safety Beam from Traffic Management Systems, St. Louis, activates all onboard radar detectors within roadway construction hazard areas without causing interference to normal police radar operations.
The company’s Myriad Safety Sentinel is an intrusion system designed to alert workers of vehicular intrusion in the work zone with a combination of sirens and lights.
Others, like the Watchdog Workzone Intrusion Alarm System from Kenco International, Ligonier Valley, Pa., have radio-linked vehicle sensors and personal alarms.
A safety warning system featuring 64 standardized messages such as “Workzone,” “Emergency Vehicle Approaching,” “Rock Slide Area Ahead” and “Train At Crossing” is in the works.
The device, according to the Radio Association Defending Airwave Rights, Tipp City, Ohio, the association representing the product’s group of manufacturers, uses existing technology similar to that used everyday in motion detectors, automatic door openers and radar detectors to alert motorists about to encounter abnormal driving situations.
The system will rely on existing, pre-approved radio frequencies to transmit an audible tone followed by a text message that scrolls across a small screen on a portable, dashboard-mounted receiver. The messages can be sent from portable, self-contained, all-weather transmitters or from in emergency vehicles.
8. Road Weather Safety. A new Road Weather Information System (RWIS) used in the Lake Tahoe Basin in Nevada has helped reduce the amount of chemicals used, improve air quality by limiting abrasives and particulate matter and lower traffic accidents and delays caused by poor road surface conditions. The system consists of two remote weather stations and was used in a test program in the Reno area to determine its effectiveness in predicting icing conditions on bridge decks and the use of deicing chemicals on US 395 north of Reno. The data generated includes intensity, duration and character of storms.
The new strategy helps the DOT reduce the amount of chemicals and abrasives involved, minimizing the effect on the environment and improving air quality. In addition, motorists benefit from reduced number of accidents and improved road conditions.
Although America’s highway systems are showing signs of age and unmanageable growth, state-of-the-art interactive telecommunications technologies like the eight listed here are helping to convert the nation’s antiquated, costly and deteriorating system into a highly efficient, low-cost transportation network. And people like James Taylor might just start singing a different tune on the way home from work: “Take it easy … take it easy … don’t let the sound of your own wheels make you crazy.” — Eagles
Action West 360-577-9150 ADDCO 612-224-8800 American Electronic Sign 509-928-2296 American Road & Transportation
Builders Association 202-289-4430 American Signal Co.404-458-7272 American Traffic Systems 602-957-9779 ASTI Transportation Systems302-328-3220 AT/Comm 617-631-1721 Electrosonic Systems Inc 612-931-7510 ESRI 909-793-2853 GDS & Digital Equipment Corp. 800-678-4120 Graphic Data Systems 303-741-8484 Highway Safety Research Board 919-962-2202 HNTB816-472-1201 Intelligent Transportation Society
of America (ITSA) 800-374-8472 International Bridge, Tunnel &
Turnpike Association (IBTTA)202-659-4620 Kenco International800-653-6069 Matrix 800-848-2330 MFS Network Technologies 708-218-7200 National Automated
Highway System Consortium 212-465-5136 Northrop Grumman Corp.516-575-8870 Nu-Metrics412-628-6370 Radio Association Defending
Airwave Rights (R.A.D.A.R.) 513-667-5472 Raytheon Engineers Constructors 212-839-1000 Solar Technology Inc. 800-475-5442 3M612-733-5416 Texas Instruments617-451-3325 Traffic Management Systems 800-274-0966 Transpo Industries Inc.914-636-1000 TRW Avionics Surveillance Group 619-592-3000 Winkomatic Traffic Systems 800-541-9593 WLI Industries 800-323-2462
The companies and associations listed are a representative sampling of those in the road and traffic technology, market.
1. Interactive Highways
2. Emergency Signal Priority
3. Electronic Tolls
4. Graphic Information Systems Capabilities (GSI)
5. Speed Cameras
6. Seamless Management Across State Borders
7. Work Zone Safety
8. Road Weather Safety
Active Tag — RFID transponders that require batteries for operation. See “Transponder” for more information.
Addressability — The ability to address bits, fields, files or other portions of the storage in a radio frequency (RF) tag.
Antenna — The device that sends and/or receives radio frequency energy in a radio frequency identification system.
Capacity — The number of bits or bytes that can be programmed into an RF tag. Includes “active storage” that is used during transactions.
Capture Window — The region of the scanner field in which a tag will operate in an RFID system. In AVI applications, the area of a toll lane or road in which a tag will operate.
Data Rate — The rate at which data is communicated between the identification tag and the interrogator in an RFID system. Typical units are bits-per-second or bytes-per-second.
Data Capacity — The amount of memory in an RF tag. Includes all storage or memory in a tag.
Exciter — The electronics that drive an antenna in an RFID system, also known as the transmitter. The antenna and the exciter together are called a scanner.
Interrogator — The device that triggers RF tags to respond with a modulated RF message.
Orientation — The alignment of the RF tag with respect to the reader, measured in pitch, roll and yaw.
Passive Tag — RFID transponders that do not have any internal power source. Their energy source is the power
emitted from an antenna. See -Transponder – for more information.
Radio Frequency — An electromagnetic wave.
Range — The maximum operable distance between the antenna and the RF tag.
Reader — A device that communicates with the transponder, containing the digital electronics that extract and separate the information from the format definition and error management bits.
Read Only — RFID systems employing RF tags that contain only pre-programmed data or an identification code.
Read/Write — The capability of RF tags to have their stored data changed by an external radio frequency signal.
Read Rate — The maximum rate at which data can be read from an RF tag.
Transponder — An electronic tag capable of receiving/storing and transmitting or reflecting digital information by means of and in response to radio frequency energy. Also know as an RFID tag. In AVI applications, the transponder can be placed on a dashboard or attached to a license plate and communicates with a computer system via an antenna placed overhead, alongside or even within the road itself.
Write Rate — The rate at which information is transferred to an RF tag. Also known as the transmission rate or data rate, it is quantified as the average number of bits-or bytes-per-second in which the complete transaction can be performed.
Source: MFS Network Technologies/Texas Instruments – TIRIS
Phoenix is planning ahead to alleviate increasing traffic congestion in the Valley of the Sun. As the population grows by leaps and bounds, a top priority of the Arizona Department of Transportation (ADOT) is the implementation of a Freeway Management System (FMS), designed to stem the flow of traffic in the metropolitan area.
Through the ’90s and into the 21st century, the FMS is being phased in to electronically link Arizona’s freeways to a central monitoring and control center via fiber optic cable.
“A significant measure of urban freeway congestion is due to incidents caused by stop-and-go traffic and disabled vehicles,” says Manny Agah, FMS project manager at ADOT.
Twenty-three variable message signs (VMS) have been installed giving advance warning of traffic conditions, 39 ramp meters controlling freeway access to keep “mainline” traffic moving and 28 closed-circuit television cameras verifying incidents detected by pavement sensors.
Traffic signals on freeway ramps and at interchanges automatically adjust to shifting traffic volumes.
In addition, 403,000 linear feet of fiber optic cable was installed to connect the highways to the control center, along with 1,036 pavement sensors to monitor traffic flow and detect congestion and 810,000 linear feet of electrical conduit. The highway sensors beneath the pavement, known as loop detectors, are spaced approximately every one-third mile in each traffic lane.
The sensors provide real-time traffic flow information to control center computers and also allow instant traffic counts. Pump stations, which keep highways clear of stormwater runoff, are monitored and controlled as part of the FMS system. Lighting, ventilation, fire suppression and other I-10 Deck Tunnel operations can also be controlled via the FMS.
Phase I of the project was designed by Kimley-Horn & Associates Inc., Phoenix, and installed by Holmes & Narver, Orange, Calif., in a joint venture with Sundt, Tucson, Ariz., and Wilson Electric, Scottsdale, Ariz., under a $21 million contract.
AVI (Automatic Vehicle Identification) — Automatic identification of vehicles through the use of readers installed in toll booths or gates and radio frequency transponders attached to or stored inside vehicles. AVL (Automatic Vehicle Location) — A feature of AVI that allows users to immediately locate commercial vehicles and fleets to reduce off-time and vehicle misuse. ATIS (Advanced Traffic Management Systems) — Technologies that manage the flow of traffic by collecting and synthesizing real-time traffic data and alerting motorists and traffic managers to situations and alternate routes. AVCS (Advanced Vehicle Control Systems) — Computer warning systems within a vehicle that help motorists avoid potential collisions and dangerous driving conditions. CVO (Commercial Vehicle Operations) — A group of technologies including weigh-in-motion (special facilities to weigh trucks without having them stop) and fleet management applications such as fuel dispensing and servicing. ETTM (Electronic Toll and Traffic Management) — A group of technologies that assist in reducing congestion at toll plazas through the automatic electronic collection. ISTEA (Intermodal Surface Transportation Efficiency Act of 1991) — Signed by President Bush on Dec. 18, 1991, this act authorized a $660 million IVHS program over the next six years. Lane Controller — A computer that controls the activities in a toll lane by monitoring and communicating with AVI readers, coin machines, toll terminals, canopy lights, patron displays (telling drivers amount owed, etc.) and closed-circuit television cameras. Plaza Computer — A computer that collects data from lane controllers, coin machines and AVI readers and creates a comprehensive individual transaction record for each vehicle passing through the toll facility. VTDM (Video Transaction Data Multiplexer) — A technology that provides a toll agency with an inexpensive method of compiling complete video-data based documentation on every vehicle in every lane.
Source: MFS Network Technologies/Texas Instruments — TIRIS
