Making highways safer is the aim of the Advanced Highway Maintenance and Construction Technology Research Center at the University of California, Davis. The center, funded by the California Department of Transportation (Caltrans), develops and deploys machines for dangerous jobs on busy highways, such as laying cones, sealing cracks and collecting litter.
Roadside construction zones are dangerous for both workers and drivers. In the last five years, there have been 30,000 collisions in work zones on California state highways, resulting in 16,000 injuries and 287 deaths, according to Caltrans figures. Thirteen Caltrans employees have been killed on the job since 1995. Nationally, over 700 deaths a year are due to crashes in work zones. Using machines and robots means that Caltrans workers are not exposed to fast-moving traffic on busy roads.
"We're using high technology to improve safety for both workers and the public," said mechanical engineering professor Steven Velinsky, the center's director.
As well as building machines for California's highways, the center generates fundamental research in areas such as robotics, mechanical design, control systems and mechatronics -- the integration of electronics into mechanical systems.
Commercialization of inventions is a major goal for the center, Velinsky said.
Prototypes of the crack sealers, the cone shooter, debris and litter removal vehicles are undergoing field trials with Caltrans, he said. A Los Angeles-based company, Clean Earth Environmental Group, has licensed the Automated Roadway Debris Vacuum (ARDVAC) for commercial development.
The "Cone Shooter" is a modified pickup truck that can lay and retrieve traffic cones at up to 10 miles per hour. One operator can quickly cone off a lane, without having to get out of the cab. In comparison, workers laying cones by hand can only carry three at a time and have to work right next to traffic. In 1994 alone, the state of California paid out over $300,000 in injury claims related to manual cone laying.
Removing roadside litter and debris is another hazardous, labor-intensive operation. Litter removal alone costs the nation half a billion dollars a year. ARDVAC is a remote-controlled vacuum cleaner that can be added onto a sweeper truck. Using a joystick control in the cab, the operator can vacuum under bushes, behind guardrails and into ditches.
Larger items such as tires, mufflers and litter bags are dealt with by the Automated Litter Bag/Debris Collection Vehicle. It uses a robot arm to pick them up and drop them in a compacting truck.
The Longitudinal Crack Sealing Machine, currently in operational trials with Caltrans, can fill and seal cracks running along the road, for example between lanes and the shoulder. The process is remote-controlled by the driver, and the machine can fill cracks at up to 5 miles per hour. That compares to a manual sealing operation that would take a large crew all day to complete two miles. Center engineers have also developed a crack sealing machine with a robot arm that can reach across a full lane and seal random cracks in the pavement.
Edited by Virginia Foran