ROBOT REPAIRMEN : Caltrans Hopes Mechanical Freeway Workers Will Reduce Fatalities Among Its Road Crews

More Caltrans road maintenance workers have been killed on the state’s highways in recent years than members of the California Highway Patrol. So robots are being developed to replace the endangered workers--and also make it possible to do more work at night, keeping freeway lanes open during the day.

Since 1972, 45 orange-clad California Department of Transportation workers have been killed and hundreds more injured by what the agency refers to as “errant motorists”--drunken drivers barreling down the freeway at 75 m.p.h. or truck drivers, occasionally high on drugs, who cannot stop their rigs before they smash into a repair crew.

In that same time period, 42 CHP members have been killed.

“It’s dangerous out there,” said Bob Ramey, deputy director for construction and maintenance in District 7, covering Los Angeles and Ventura counties.

To try to reduce this carnage, Caltrans has embarked on a research program to develop robotic machines that not only will take maintenance workers off the roads but also allow repairs to be done in less time, thereby helping with the congestion problems that are becoming increasingly critical in urban areas.

The UC Davis campus has a three-year, $1.2-million Caltrans contract to develop automatic devices that will seal freeway cracks, paint road stripes, replace pavement markers and pick up litter.

In the future, there may also be machines to patch potholes and repair crash barriers.

“We’d like to automate the entire maintenance operation,” said Andrew A. Frank, professor of mechanical engineering at UC Davis and head of the “maintenance robotics” program. “We want to get workers off the road because the work is dangerous and we want to speed up the process. We think most of these jobs can be done five to 10 times faster than they are now.”

The first project undertaken by Frank and his group of half a dozen faculty members and 20 or so graduate and undergraduate students is a robotic device to replace pavement markers.

These markers, some reflecting and others non-reflecting “rumble markers,” are placed every 48 feet on freeways and highways. On little-used roads, they can last for years, but on a heavily traveled road such as the Long Beach Freeway, they can wear out in a few weeks.

The present method involves a two-man crew, with one driving the vehicle and the other wedged into a small compartment at tire level. While the vehicle rumbles along, the Caltrans worker in the lower compartment squirts epoxy on the markers and smacks them down on the lane. If all goes well, the team can replace about 200 markers in an hour.

In the system under development at UC Davis, glue is squirted onto the roadway by a worker riding in a bucket seat, then markers automatically slide down a chute and are tamped into place. This machine, which Caltrans expects to have in service within a year, can replace 600 to 800 markers an hour.

Industry Involvement

UC Davis researchers will do much of the work on the marker replacement device but Frank expects other universities and especially private industry to develop some of the other machines, under general supervision of the Davis campus.

He pointed out that not much can be done with the $1.2 million the state is providing and that “cost sharing by private industry will be necessary” if these projects are to come to fruition.

“We will monitor the projects,” Frank said, “but our objective is to stimulate industry because they’re the ones who are going to benefit--they can sell these things to the entire world.”

Among the other automatic devices that Frank and his Davis colleagues hope to develop are:

* A device that can clear large debris from the roadway while moving at speeds of up to 30 m.p.h. Currently, lanes are closed while workers on foot clear dead animals, wayward tires, garbage cans and homicide victims from the freeways and the bushes alongside.

“We do run across dead bodies or parts of bodies,” Ramey said. “I suppose that’s the most disagreeable part of clean-up work.”

‘Handy Escape Routes’

Ramey explained that local police and the CHP take care of accident victims but “I’m talking about homicides--people get killed and dumped along the freeway, you know. Freeways are handy escape routes for criminals. . . . Mostly, they knock ‘em off and roll ‘em down the bank and we find ‘em in the brush.”

Caltrans already has an automated “litter gitter,” with 6-foot robotic arms, that can pick up medium-sized debris, but it is slow. The new contraption will be faster and will be able to pick up larger objects.

* A machine that will seal freeway and roadway cracks, a job now done by a Caltrans worker walking along with a kettle filled with crack sealer. In the new device, electronic sensors detect cracks; then valves open automatically to seal them. Caltrans officials expect to have such a machine in service in about three years.

* A device that will detect faded road markings and automatically repaint them. Presently, Caltrans employs a dozen paint stripers statewide but hopes to replace them with machines in about three years.

Frank also hopes that pothole filling, crash barrier repair and other maintenance jobs eventually can be transferred from men to machines.

Not Much Pizazz

In the past, he added, “the maintenance area is something that’s been completely ignored by researchers, I guess because it doesn’t have very much pizazz.”

But the growing problem of traffic congestion, combined with the rapid development of electronic sensors and small computers that can be placed aboard vehicles, make this kind of research more attractive, he said.

If Caltrans is to succeed in its goal of doubling road capacity and reducing accidents by 50% in the next few years, better and faster maintenance will play a crucial role.

“If we’re going to increase capacity, we’re going to have less time for maintenance,” said Robert E. Parsons, director of the UC Program on Advanced Technology on the Highway (PATH). “That means we’ve got to have a maintenance program to get workers off the road and do things faster.”