A mobile fleet of Universal Robots now receives daily work orders to solve ever-changing tasks for high-mix/low-volume electronics manufacturer Scott Fetzer Electrical Group (SFEG; Fairview, TN). Supplied by Universal Robots USA Inc. (East Setauket, NY; Odense, Denmark), the collaborative UR robots have optimized production by 20%, taking over monotonous and potentially hazardous tasks from employees now reallocated to more rewarding jobs.
SFEG was formed in 2010 to bring together the capabilities of three Scott Fetzer Company businesses: France Power Solutions, Northland Motor Technology, and Kingston Products. Located on the outskirts of Nashville, the company designs and manufactures electrical power products, including transformers, power supplies, motion controls, and drive systems.
“One day, Waldo would be bending sheetmetal, the next day he would be performing pick-and-place tasks, and the third day we would take him to Manufacturing Day at the local high school,” said Matthew Bush, director of operations at SFEG, a manufacturer of a wide range of electrical motors and components.
The UR robots are a new type of robot classified as collaborative due to their interactive design. Collaborative robots are easy to set up for a new task and feature built-in safety systems that enable the robot arm to automatically stop operating if it encounters objects or people in its route.
Bush came across this new automation solution as he was looking for ways to make SFEG more competitive on the global scale, while taking more advantage of existing machinery. “One of our biggest challenges as a high-mix/low-volume producer is that most of our lines don’t run all the time. Trying to find a way to put robots on the line in the traditional sense was a very big challenge,” said Bush.
“We wanted to build a mobile, flexible robot force, and the only way we would accomplish this was with a collaborative robot. We only saw a couple of offerings and the UR robot was the only robot that we thought could do the job. It’s got the speed and precision of a standard industrial robot with the ability to move around and work next to humans,” said Bush.
SFEG placed the UR robots on pedestals with wheels and is now building the fleet of mobile UR robots deployed throughout the sheet metal department. The robots are being integrated into the entire production cycle from cutting the initial blank on the blanking press to forming, folding and final assembly of the electrical components. Additional robots are planned to help tend the turret presses and press brakes.
General Manager Rob Goldiez said, “We’re seeing about a 20% increase having a pace setter with the Universal Robots working hand in hand with our people.” The UR robots working the motor field line are a UR5 and a UR10 robot named after their payload in kilos. The robots all feature 0.1-mm repeatability and span in reach from 19.7 to 51.2″ (500–1300 mm).
The UR5 is placed at the end of the line right next to an employee that hands the robot a motor field part. The UR5 picks up the part, puts it in a holder, picks up a wire cutter to trim the wires, and then places the part for the UR10 robot to pick up and place on a conveyor for final assembly.
“We can interlock multiple robots together and read through Modbus the TCP connections and robot status. We can also pass information along to other software packages, and collect data. It opens up a lot of doors to do a lot of things we’re just now beginning to look at,” said principal engineer Jamie Cook.
A UR robot comes with a touch screen pendant that all programming is done through. Directing the robot arm can be done either through arrow keys on the screen, or by simply grabbing the robot arm and “teaching” it the desired moves between waypoints. That eliminated the structured text programming Cook usually had to code when working with traditional robots.
“It was really easy to learn and it went much smoother than I anticipated. I would say it took a third to half of the implementation time out of it based on previous experiences I’ve had,” Cook said.
As SFEG looked for tasks to automate, eliminating monotonous and potentially dangerous tasks was the number one priority. Another task now handled by the mobile UR robot fleet is filling epoxy into circuit boards.
In the past, employees would make up a big batch of circuit boards and would stand there and manually fill them with two-part epoxy and send them down the curing line. Today, the robot does that all day long enabling us to go to a one-piece flow. Safety hazards are now avoided on the motor field line by having a UR robot handle the wire cutting.
“It’s a potential carpal tunnel syndrome application cutting about 16,000 wires a day by hand. So we thought that was a great place to put robots—let them get carpal tunnel!”
“We’re seeing about 1 to 1 movement of people from where we put in a robot that allows us to move a person to another area of the business. We have 14 robots from Universal Robots right now and as we have all those implemented, we expect to be able to reposition 14 employees,” said Goldiez.
One of the next robot tasks currently being developed at SFEG is putting c-clips on armatures. At the varnish oven, two UR10s will be loading and unloading baskets with motors. One UR10 is already deployed at the end of the varnish conveyor, working as a simple transfer station, moving baskets between lines.
“We’re looking at everything we’re designing now new to make sure we can assemble it with a robot. If we can’t put that together with a robot, we’ve got to go back to the drawing board and try again.”
For more information from Universal Robots USA Inc., go to www.universal-robots.com, or phone 631-610-9664.
This article was first published in the March 2016 edition of Manufacturing Engineering magazine. Read “Mobile Robots Increase Worker Productivity, Safety” as a PDF.