How a Collaborative Robot Helped Wisconsin Plastics Boost Efficiency and Empower Workers

When the team at Wisconsin Plastics Inc. (WPI) first met their new coworker—a UR5 collaborative robot from Universal Robots—they worried it might replace them. Today, they see it as a catalyst for higher efficiency.

“Initially everyone was concerned about the robots replacing them,” says plant manager Carl Bartle. “Once they realized the robot was there to help our own efficiency, there was a lot of excitement.”

Based in Green Bay, WPI is a contract manufacturer specializing in injection molding and assembly, and it also produces its own line of paper‑towel dispensers. To test the potential of cobots, the company chose one of its most complex assembly lines as a pilot.

“We picked one of our more complicated assembly lines for the cobot, one that actually had the most intense human interaction and the most variable rate to it,” Bartle explains. “If we could succeed there, we could do anything.”

KEEPING PACE

A key concept for WPI was maintaining a steady, repeatable production rate—“not getting employees to work faster, but creating a process that stays on schedule.” The towel‑dispenser line, where the cobot was first deployed, previously required parts to be molded in one building, packaged, and then moved across the street to the assembly facility. That setup was inefficient and risky: a shortage of assembly staff could halt the entire line. By separating the injection molding machine from the assembly area, the company could continue molding parts even if assembly personnel were short.

Unlike many cobots that operate in isolation, WPI’s UR5 is positioned between two injection machines that produce the dispenser’s body and cover. The robot removes molded parts, places them on a pad‑printing fixture for the first logo, switches the housings to a second fixture for a second logo, and then pivots to deposit the parts on a conveyor for final assembly. See the cell in action here.

“By having the robot in between, we reduced the assembly line’s footprint,” Bartle notes. “The cobot can perform multiple tasks in less space than a human line would require.”

WPI also installed a new pad printer and custom integration fixtures. The two‑cavity molds allow the robot to grab both parts from a single orientation using a rotating fixture, streamlining the workflow.

The human footprint has shrunk significantly. With no need for separate assembly tables, workers combine components directly off the conveyor. “It’s not a dramatic square‑footage cut, but the line is now a compact, short cell that sits just outside the machine’s footprint,” Bartle explains.

Throughput has risen because the cobot establishes a consistent cadence that workers can match. “Machines run at a fixed speed, whereas human pace fluctuates,” Bartle says. “The cobot keeps the pace steady, allowing our team to maintain that rhythm.”

MORE COBOTS COMING

After the initial apprehensions faded, WPI’s workforce embraced the technology and sought ways to expand its role. “The assemblers on the line were the ones proposing ideas—where to position the robot, which side to pick from, how to orient the conveyor,” Bartle says. “Their input pushed the integration to the next level.”

The success has prompted plans to add four more UR cobots over the next few years. Bartle acknowledges that involving the manufacturing team, shift supervisors, and shop technicians earlier would have accelerated the process.

Looking ahead, WPI envisions using cobots for part transport and packaging of finished assemblies. “We can automate low‑skill, repetitive tasks, freeing skilled labor for more complex jobs,” he says. “It also creates opportunities for robot programmers.”

“This is an opportunity to transform how we use our workforce,” Bartle concludes. “By removing tedious tasks, we enable employees to tackle higher‑value work and help us grow in an era where we’re often short on staff.”

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