Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Automated system installs pavement markers

12.01.2007
System improves safety for road crews and drivers

On rainy nights in Georgia and across the nation, drivers greatly benefit from small, reflective markers that make roadway lanes more visible. A new automated system for installing the markers is expected to improve safety for workers and drivers.

There are more than three million of these safety devices, called raised pavement markers (RPMs), in service on Georgia highways. They are installed and then need to be replaced about every two years by road crews who consider the task one of the riskiest they face. Workers typically ride on a seat cantilevered off the side of a trailer just inches from highway traffic.

Manual RPM placement is not only risky for personnel, but it is also expensive and time-consuming. A typical RPM placement operation includes four vehicles and a six-person crew. All the vehicles must stop at each marker location, so there is tremendous wear on the equipment and increased fuel use.

The Georgia Department of Transportation (GDOT) believed there was a better way to do it and funded the Georgia Tech Research Institute (GTRI) to develop a first-of-its-kind system capable of automatically placing RPMs along the lane stripes while in motion. After almost three years of research and development, GTRI expects to deliver a prototype system early this year. Because of widespread interest in the system, researchers will present a report on their project on Jan. 23 at the National Research Council's Transportation Research Board Annual Meeting in Washington, D.C.

"The advantages of our automated system are: it's less labor-intensive, it's faster and safer, uses less fuel, and it causes less wear and tear on GDOT equipment," explained project manager Wiley Holcombe, a GTRI senior research engineer.

Engineers conducted the work in two phases. First, they designed an RPM-placement mechanism using pressure-sensitive adhesive and a lane-stripe tracking system. Then, they developed a full-scale, truck-mounted RPM placement system. It is based on a single GDOT-owned truck and includes the lane-stripe tracking system, and electrical power, compressed air, hydraulic power, and adhesive melting and dispensing systems. Some components of the system were off-the-shelf parts, but the GTRI Machine Services shop fabricated most of the custom components for the system, Holcombe notes. After some field-testing, the project resulted in a prototype system capable of dispensing an RPM onto the pavement along with the necessary hot-melt adhesive applied at 380 degrees Fahrenheit while traveling at 5 miles an hour. A pattern-change mechanism can position two placement mechanisms to accommodate any of GDOT's five specified RPM placement patterns, Holcombe explains.

Operation of the system only requires two people. An operator on the back of the truck loads the adhesive melters with adhesive and stacks RPMs in the hoppers from which they are dispensed, depending on the placement pattern. Meanwhile, the driver of the truck must maintain alignment between the stripe pattern on the road and a caster wheel on a boom in front of the truck. Also, the driver touches a computer screen in the cab to indicate to the placement system the new stripe pattern each time the caster wheel crosses a stripe pattern change.

RPMs are dispensed from the hoppers onto a loader arm, which deposits them onto a telescoping slide that connects to a placement mechanism on an attached carriage. The carriage has a 3-foot range of travel and is moved laterally to keep the placement mechanism centered along the road stripe. RPMs are then typically applied about 80 feet apart. It takes about 35 milliseconds from the time the edge of the RPM hits the ground to the time it's flush with the road, Holcombe notes.

"The GDOT's primary use for the automated RPM placement machine will be placing markers on the skip lines for interstate and multi-lane highways," said GDOT spokeswoman Karlene Barron. "These types of routes pose the highest safety risks to our employees and equipment.

"The GDOT also plans to use the system on high-traffic-volume secondary or two-lane roads, when possible," Barron added. "Using the automated system, we will not have to stop at every placement, which will increase safety and productivity plus reduce wear and tear on GDOT equipment. Plus the operator will be high on the back of the machine instead of near ground level."

Six of GDOT's seven district offices have their own RPM placement crews, and there are four other crews that work statewide. GDOT also plans to use the system in the metro Atlanta area.

GTRI's automated raised pavement marking system could be used outside Georgia, though Holcombe explains that its design is most appropriate for Southern states with warmer climates. In regions that get a lot of snow, RPMs must be applied somewhat differently to reduce the risk of damage to RPMs by snow-clearing equipment.

Jane Sanders | EurekAlert!
Further information:
http://www.gatech.edu

More articles from Transportation and Logistics:

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

nachricht From parking garage to smart multi-purpose garage
19.07.2017 | Fraunhofer-Institut für Arbeitswirtschaft und Organisation IAO

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: Fizzy soda water could be key to clean manufacture of flat wonder material: Graphene

Whether you call it effervescent, fizzy, or sparkling, carbonated water is making a comeback as a beverage. Aside from quenching thirst, researchers at the University of Illinois at Urbana-Champaign have discovered a new use for these "bubbly" concoctions that will have major impact on the manufacturer of the world's thinnest, flattest, and one most useful materials -- graphene.

As graphene's popularity grows as an advanced "wonder" material, the speed and quality at which it can be manufactured will be paramount. With that in mind,...

Im Focus: Exotic quantum states made from light: Physicists create optical “wells” for a super-photon

Physicists at the University of Bonn have managed to create optical hollows and more complex patterns into which the light of a Bose-Einstein condensate flows. The creation of such highly low-loss structures for light is a prerequisite for complex light circuits, such as for quantum information processing for a new generation of computers. The researchers are now presenting their results in the journal Nature Photonics.

Light particles (photons) occur as tiny, indivisible portions. Many thousands of these light portions can be merged to form a single super-photon if they are...

Im Focus: Circular RNA linked to brain function

For the first time, scientists have shown that circular RNA is linked to brain function. When a RNA molecule called Cdr1as was deleted from the genome of mice, the animals had problems filtering out unnecessary information – like patients suffering from neuropsychiatric disorders.

While hundreds of circular RNAs (circRNAs) are abundant in mammalian brains, one big question has remained unanswered: What are they actually good for? In the...

Im Focus: RAVAN CubeSat measures Earth's outgoing energy

An experimental small satellite has successfully collected and delivered data on a key measurement for predicting changes in Earth's climate.

The Radiometer Assessment using Vertically Aligned Nanotubes (RAVAN) CubeSat was launched into low-Earth orbit on Nov. 11, 2016, in order to test new...

Im Focus: Scientists shine new light on the “other high temperature superconductor”

A study led by scientists of the Max Planck Institute for the Structure and Dynamics of Matter (MPSD) at the Center for Free-Electron Laser Science in Hamburg presents evidence of the coexistence of superconductivity and “charge-density-waves” in compounds of the poorly-studied family of bismuthates. This observation opens up new perspectives for a deeper understanding of the phenomenon of high-temperature superconductivity, a topic which is at the core of condensed matter research since more than 30 years. The paper by Nicoletti et al has been published in the PNAS.

Since the beginning of the 20th century, superconductivity had been observed in some metals at temperatures only a few degrees above the absolute zero (minus...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Call for Papers – ICNFT 2018, 5th International Conference on New Forming Technology

16.08.2017 | Event News

Sustainability is the business model of tomorrow

04.08.2017 | Event News

Clash of Realities 2017: Registration now open. International Conference at TH Köln

26.07.2017 | Event News

 
Latest News

Researchers devise microreactor to study formation of methane hydrate

23.08.2017 | Materials Sciences

ShAPEing the future of magnesium car parts

23.08.2017 | Automotive Engineering

New insights into the world of trypanosomes

23.08.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>