Best Practice

BEST PRACTICE:

J2−2: Real−Time Traffic Information

DESCRIPTION:

These systems are designed to keep drivers informed of current traffic conditions on the road ahead. Delay information (in units of time or distance) and other messages are displayed to motorists using changeable message signs. These systems use queue length detectors, traffic sensors, and communications devices to transmit data, and calculate delay. Traffic information systems can run 24 hours a day, 7 days a week, keeping motorists informed of traffic conditions, the need to be cautious, or take an alternative route, during work zone projects.

• The Computerized Highway Information Processing System (CHIPS) relies on the queue length detector developed under the Strategic Highway Research Program. A series of variable message signs warn motorists of any slowed or stopped traffic or lane blockages ahead, as well as provide estimated length of delay, based on queue detector information. The system uses radio signals to transmit information.

• ADDCO (SmartZone) gathers data using sensors, monitors and manages traffic flow via a CCTV camera, and updates drivers with real−time information using a 6' by 3' dynamic message sign.

• ADAPTIR is a portable real−time message system that detects traffic speeds at various locations using sensors and sends data to a computer base station. A computer model is used to calculate travel delay at a set of locations. Information is displayed on changeable message boards.

• The Travel Time Prediction System (TIPS) collects real−time information on traffic flow through sensors at the roadside and uses these data to calculate estimated travel times between two points, such as from the beginning to the end of a work zone. This travel time information is then displayed on portable, electronic changeable message signs in real−time. Traffic flow is detected using microwave radar sensors, and radio communication devices transfer the data from the sensors to an onsite PC for processing into travel time estimations and then to the message signs. Sensors and radios are powered by solar panels. Radio communications devices use 220 Mhz radios for wireless communication.

REASON(S) FOR ADOPTING:

These systems are able to: lessen motorist frustration by informing them of what to expect and enabling them to choose alternate routes to avoid delays, reduce user costs, and increase safety (especially on highways with limited sight distance).

PRIMARY BENEFIT(S):

Reduced crashes, providing travelers with information on which to make alternate route decisions, and reduced motorist frustration.

MOST APPLICABLE LOCATION(S)/PROJECT(S):

Any work zone exposed to traffic. May be most useful in areas with high traffic volumes and highways with limited sight distance.

STATE(S) WHERE UTILIZED:

Illinois, Ohio

SOURCE/CONTACT(S):

Charleen Boudreau, Construction Field Engineer, Illinois DOT
Telephone: (309) 671−3657
E−mail: BoudreauCA@nt.dot.state.il.us

Rodger Dunn, Ohio DOT
Telephone: (614) 644−8179
E−mail: rdunn@dot.state.oh.us