This article was published in an issue of DIRECTIONS magazine, a publication specializing in providing information to the paint finishing industry.

New York Mayor Praises Toledo Robot Painting System

"It's a robotic Rembrandt," says Mayor Edward Koch of New York City.
The mayor was referring to the Department of Sanitation's new computerized twin-robot painting system. It was developed by the Toledo-based DeVilbiss Company to paint the city's fleet of refuse collection trucks, salt spreaders and other heavy-duty vehicles.

(PHOTO INSETS: Three photos showing painting robots painting garbage truck. CAPTION: The two-robot system can paint an entire truck in less than forty-five minutes.

Removing Workers from a Hostile Environment
   Although the robots do paint with the precision of a grand master, the system was installed principally to remove human painters from a hostile environment. Before the arrival of the robots, painters sprayed vehicles manually wearing protective clothing and hoods -- and were enveloped in a potentially harmful cloud of paint spray.

Two Robots Work Together
   The system installed at the Sanitation Department's huge Central Repair Shop in Woodside, Queens uses two DeVilbiss TR-3500 robots, one on either side of the vehicle being painted. The arm and wrist actions of the robots provide six axes of motion that closely duplicate the movements of a human painter.
   Each of the robots rises atop a rail-mounted XYZ transfer table that provides movement in three directions. The robots are able to move vertically to allow paint coverage from top to bottom and horizontally to coat from back to front. Plus, a third movement of the table allows the robot to move in and out to follow the varying contours of the vehicle.
   The robot and transfer table are mounted on a mobile platform. When air is injected into the platform, it floats. Because each truck will have a different alignment after it is driven into the spray booth, the floating platform allows the entire assemble to be manually towed into the correct spraying position.
   Each robot is programmed to paint one side of the truck in four foot sections. The truck is first painted white. The computer controller then changes to black for the tires, and then to green for portions of the undercarriage. An anti-collision device on the gun prevents any accidental encounter between the robot arm and the truck.
   And entire truck can be painted in about forty-five minutes. The Department annually paints about 625 vehicles to prevent rust and costly body work. Currently the robot painting system is painting about four trucks a day.

On-the-job Training
   Programming the robots is simple, so the on-line paint shop painters were trained on the job by John Edelhauser, a DeVilbiss senior field service engineer.
   Programs are entered as the operator physically leads the robot through the desired finishing operation. As the operator moves the manipulator arm, position information is committed to memory up to eighty times per second on each of six axes. Once programming is complete, the robot will continuously repeat the required path and functions.

(PHOTO INSET: Operators being trained CAPTION: DeVilbiss-trained operators learned how to use the robot system while on the job.)

   John was also responsible for the difficult task of setting up the entire robot installation, including initial testing and the follow-ups after the system was in operation.
   The workers responsible for the more complex task of system maintenance were trained in the DeVilbiss robotics school in Toledo, Ohio.

"We're Proud of Our Robots"
   Sanitation Commissioner Norman Steisel, a leader in health and safety measures for his department, says, "The Department will enjoy savings of $44,000 each year in material usage and labor. But more important is the improvement in the quality of human working conditions."
   The entire project centered on the involvement of a Labor-Management Committee working together to remove human workers from a hostile environment. "It was a joint effort," says Department Commissioner Ronald Contino, in charge of Support Services. "And DeVilbiss representatives were very instrumental in helping us put this excellent system into operation. We're very proud of our robots. We show them off every chance we get."

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