Mobile cobots handle round-the-clock production

EVCO Plastics

In short

EVCO Plastics in DeForest, Wisconsin is a custom injection molder facing the challenge of having to staff round-the-clock production with fast-changing processes. A mobile fleet of Universal Robots now handles a wide range of tasks such as dispensing, assembly, quality inspection, harvesting of 3D printers and packaging. Deploying the UR cobots was fast and easy thanks to the seamless integration with UR+ certified products such as force/torque sensors, vision cameras and part feeders.

The business transformation

Being located in a region with low unemployment meant that EVCO had trouble staffing the third shift in the company’s 24/7 production. Manning cells with repetitive and tedious tasks, handling parts assembly, machine tending, and packaging was especially hard. The company did not want complex, fixed automation with safety guarding that would take up valuable real estate on an already tightly packed factory floor. EVCO was also looking for a versatile automation solution that could be applied to several jobs with costs spread out between different customers

EVCO Plastics

Industry Plastic and Polymers

Country North America

Number of Employees 100-500

Cobots used UR5 & UR10

Video — EVCO Plastics, USA

Collaborative additions

EVCO Plastics has now deployed two UR5 and two UR10 at the DeForest plant. Named after their payload in kilos, the cobots are placed on wheels and can be moved around the factory floors. Jason Glanzer, automation engineer at EVCO plastics, is not new to robotics—EVCO has numerous traditional, Cartesian robot cells—but what surprised him about the cobots was “how nicely they play with others” as he puts it. “The biggest difference between hard automation and collaborative robots is the set-up time. These cobots interface well with many products--UR has really been on top of continuously improving compatibility, which was really important for us,” he says, highlighting the UR+ platform that certifies grippers, vision cameras, software and other peripherals to work seamlessly with UR cobots.

Self-sufficient automation

The simple set-up and operation of the cobots also means that EVCO can run them on the third shift without having to rely on having automation engineers on hand. “If something goes wrong in the middle of the night, one of our set-up guys can go over there and get the cell up and running without having to call an automation technician or engineer onto the plant floor,” he explains.

One UR5 is currently deployed in an intricate assembly task. In the cell, the UR5 picks up a gearbox used in lawn mowers, places it into a grease dispenser and then inserts a cap to seal the grease port. Placing the cap correctly is a tricky task made simpler by the UR+ certified FT300 force/torque sensor from Robotiq. “Adding the sensor to the end of the UR5 arm allows the cobot to “feel” when the cap is inserted correctly, using a spiral motion,” explains Glanzer.

Intuitive interface

The UR+ software handshake means that all programming of the sensor happens directly through the cobot’s teach pendant, with the same intuitive interface used to program the cobot itself. “Without the UR+ integration we would have had to create a considerable amount of script code to accomplish a task like this,” explains Glanzer. The UR5’s teach pendant has two other UR+ interfaces: a Cognex vision camera and an Asycube Flexible Part Feeder from Asyril. The feeder spits out the caps on a surface that vibrates until the caps are spread out facing the right side up, then the vision camera mounted above the surface snaps an image of the caps’ positions, instructing the UR5 on where to pick them up.

Removing human error

After the cap is successfully inserted, the UR5 places the gearbox on a scale to make sure the grease has been added. If the gearbox does not weigh the correct amount, the UR5 places it in a reject box. “Once the UR5 takes control of the part, we know we were going to get a good part,” says Glanzer. This is in contrast to human operators, who were prone to forget steps in the assembly process.

UR10 takes on tedious task

Another tedious task now automated with a UR10 is the harvesting of plates in EVCO’s 3D printer farm, which consists of six polymer printers that run 24/7 to serve EVCO’s own internal tooling needs as well as to produce parts for outside customers.

Cobots help printers run all day

The printer cell can now work continuously without human oversight for as long as build plates are available. “We can run the printers 24 hours a day now, which we couldn’t do before,” says Glanzer. “We plan to take on more small jobs.The possibilities are part of the beauty of the solution.”

Traditionally it would take up to several weeks or more to automate a new project; whereas now, you roll the cobot out to the floor, you do some programming, and it can be up and running in two days.

Jason Glanzer, automation engineer, EVCO Plastics

UR changes the formula

Next door, in EVCO’s vast injection molding hall, Cartesian robots de-mold parts and place them on a guarded conveyor. A UR10 picks up the parts from the conveyor and places them in a box using the cobot’s built-in palletizing wizard. “This is another process that is really simplified now,” says Glanzer. “Using the palletizing routine means there’s a lot fewer positions that need to be taught, you’ll have a lot more consistency, and you don’t need to run external counters to keep track of where you’re at in your program and where you’re stacking the parts.”

Like the UR5 in the assembly cell, the UR10 on the packaging line also uses force/torque sensing: first to check that all four corners of the box are where they’re supposed to be, and second to place cardboard sheets between each layer of parts in the box.

Due to the mobile nature of the UR cobots, the cost savings can now be spread out between many different jobs. “We don’t come to the customer with this large cost, saying; ‘Hey, you need to buy this robot that’s going to run this one job.’ We take the cost and we allocate it out over several customers, so that makes us really cost-competitive,” explains Degenhardt, adding how in the past his team was always stuck in the quandary between adding more labor vs. deploying automation. “We would start adding up the price of automation and it just didn’t make sense. UR changes that formula quite a bit,” he says.