Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Software Uses In-Road Detectors to Alleviate Traffic Jams

26.02.2003


Benjamin Coifman


The same in-road detectors that control traffic lights and monitor traffic could soon respond quicker to traffic jams, thanks to software developed by an Ohio State University engineer.

In tests, the software helped California road crews discover traffic jams three times faster than before, allowing them to clear accidents and restore traffic flow before many other drivers would be delayed.

This technology could also provide drivers with the information they need to plan efficient routes, and even improve future road design, said Benjamin Coifman, assistant professor of electrical engineering and civil and environmental engineering at Ohio State.



Many drivers have probably noticed the buried detectors, called loop detectors, at intersections. A square outline cut into the pavement marks the spot where road crews have inserted a loop of wire. When a car stops over the loop, a signal travels to a control box at the side of the road, which tells the traffic light to change.

Though the loop detectors are barely more than metal detectors, they collect enough information to indicate the general speed of traffic, Coifman said. So he set out to use the detectors in a new way.

In the March issue of the journal Transportation Research, he describes how he was able pinpoint traffic congestion and accurately measure vehicles’ travel time using standard loop detectors.

With the software, a small amount of roadside hardware, and a single PC, a city could significantly improve traffic monitoring without compromising drivers’ experience of the road, Coifman concluded. That’s important, he said, because good traffic management can’t be obtrusive.

“If transportation engineers are doing their job well, you don’t even realize they’ve improved travel conditions,” he said.

Coifman began this work while he was a postdoctoral researcher at the University of California, Berkeley. In 1999, he installed computer network hardware in control boxes along a three-mile-long stretch of road near the Berkeley campus, and took traffic data from loop detectors every third of a mile.

He then wrote computer algorithms that can capture a vehicle’s length as it passes over a detector. Once a vehicle of similar length passed over the next loop, the computer could match the two signals and calculate the vehicle’s travel time. Based on each car’s travel time, the software was able to determine within three and a half minutes after traffic began to slow that a traffic jam had formed.

Because drivers’ behavior isn’t predictable, the new algorithms had to take many human factors into account. Among other factors, Coifman had to consider people changing lanes, entering and exiting from ramps, and “rubbernecking” -- the delay to drive time caused by people who slow down to look at accidents or other events.

“Traffic is a fluid like no other fluid,” Coifman said. “You can think of cars as particles that act independently, and waves propagate through this fluid, moving with the flow or against it.”

After an accident, it may take a long time for the telltale wave of slow moving traffic to propagate through the detectors. With the new algorithm, Coifman can detect delays without waiting for slowed traffic to back up all the way to a detector. This improved response time is important, because the personal and financial costs grow exponentially the longer people are stuck in traffic.

The detectors can’t obtain any specific information about the make or model of car, he said, and a margin of error prevents the software from identifying more than a handful of cars in any one area at one time.

But that’s enough information to gauge traffic flow, and the benefits to motorists can be enormous.

The average American city dweller wastes 62 hours per year stuck in traffic, according to the 2002 Urban Mobility Study by the Texas Transportation Institute. The institute measured traffic delays in 75 major cities, including Columbus, Ohio, where the average delay is 36 hours per year; Cleveland, where the average is 21 hours per year; and Cincinnati, where it’s 43 hours per year.

According to the same study, traffic jams cost the average city $900 million in lost work time and wasted fuel every year.

The Ohio Department of Transportation (ODOT) has already begun using loop detectors to help motorists spend less time in traffic. When drivers head south into Columbus on Interstate 71 during business hours, an electronic sign just north of the city displays the average drive time into downtown.

As such information becomes more common, drivers can plan their routes more efficiently, Coifman said. He’s working with ODOT to further improve travel time estimates.

The software would work with other vehicle detection systems too, such as video cameras. But installing these new systems can cost as much as $100,000 per location, and retrofitting existing equipment to use Coifman’s software would only cost a fraction as much.

This work was supported by the Partners for Advanced Highways and Transit Program of the University of California, the California Department of Transportation, and the United States Department of Transportation, Federal Highway Administration.



Contact: Benjamin Coifman, (614) 292-4282; Coifman.1@osu.edu
Written by Pam Frost Gorder, (614) 292-9475; Gorder.1@osu.edu

Pam Frost Gorder | Ohio State University
Further information:
http://www.osu.edu/researchnews/archive/traffic.htm
http://www.ceegs.ohio-state.edu/faculty/coifman/index.shtml

More articles from Transportation and Logistics:

nachricht Study sets new distance record for medical drone transport
13.09.2017 | Johns Hopkins Medicine

nachricht Researchers 'count cars' -- literally -- to find a better way to control heavy traffic
10.08.2017 | Florida Atlantic University

All articles from Transportation and Logistics >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Attoseconds break into atomic interior

A newly developed laser technology has enabled physicists in the Laboratory for Attosecond Physics (jointly run by LMU Munich and the Max Planck Institute of Quantum Optics) to generate attosecond bursts of high-energy photons of unprecedented intensity. This has made it possible to observe the interaction of multiple photons in a single such pulse with electrons in the inner orbital shell of an atom.

In order to observe the ultrafast electron motion in the inner shells of atoms with short light pulses, the pulses must not only be ultrashort, but very...

Im Focus: Good vibrations feel the force

A group of researchers led by Andrea Cavalleri at the Max Planck Institute for Structure and Dynamics of Matter (MPSD) in Hamburg has demonstrated a new method enabling precise measurements of the interatomic forces that hold crystalline solids together. The paper Probing the Interatomic Potential of Solids by Strong-Field Nonlinear Phononics, published online in Nature, explains how a terahertz-frequency laser pulse can drive very large deformations of the crystal.

By measuring the highly unusual atomic trajectories under extreme electromagnetic transients, the MPSD group could reconstruct how rigid the atomic bonds are...

Im Focus: Developing reliable quantum computers

International research team makes important step on the path to solving certification problems

Quantum computers may one day solve algorithmic problems which even the biggest supercomputers today can’t manage. But how do you test a quantum computer to...

Im Focus: In best circles: First integrated circuit from self-assembled polymer

For the first time, a team of researchers at the Max-Planck Institute (MPI) for Polymer Research in Mainz, Germany, has succeeded in making an integrated circuit (IC) from just a monolayer of a semiconducting polymer via a bottom-up, self-assembly approach.

In the self-assembly process, the semiconducting polymer arranges itself into an ordered monolayer in a transistor. The transistors are binary switches used...

Im Focus: Demonstration of a single molecule piezoelectric effect

Breakthrough provides a new concept of the design of molecular motors, sensors and electricity generators at nanoscale

Researchers from the Institute of Organic Chemistry and Biochemistry of the CAS (IOCB Prague), Institute of Physics of the CAS (IP CAS) and Palacký University...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

2nd International Conference on High Temperature Shape Memory Alloys (HTSMAs)

15.02.2018 | Event News

Aachen DC Grid Summit 2018

13.02.2018 | Event News

How Global Climate Policy Can Learn from the Energy Transition

12.02.2018 | Event News

 
Latest News

Basque researchers turn light upside down

23.02.2018 | Physics and Astronomy

Finnish research group discovers a new immune system regulator

23.02.2018 | Health and Medicine

Attoseconds break into atomic interior

23.02.2018 | Physics and Astronomy

VideoLinks
Science & Research
Overview of more VideoLinks >>>