Autonomous mobile robots could change metal fabrication

Interoperable autonomous mobile robots (AMR) could make automation more flexible, especially as you go farther down the metal fabrication value stream. Getty Images

If you want to automate laser cutting or punching, you’ve got plenty of options, from simple loading and unloading to a range of tower systems. Part removal and stacking automation is starting to proliferate too. The latest lasers offer beam control that make automated denesting much more reliable than it used to be.

Then, stacked ever so neatly on a pallet, the parts wait. Then wait some more. At the end of all this technical wizardry, cut parts still end up being moved downstream the way they’ve always been moved—with the fork truck. Machines can cut parts entirely unattended, but even the most automated fab shops still need people to take parts from one operation to the next.

Exceptions exist, especially in production lines dedicated to certain product families. A shop also might have a flexible manufacturing system that connects cutting with panel bending. Some recent systems even connect laser cutting and the press brake, with towers acting as a material buffer between two processes with vastly different cycle times.

Regardless, choices in automation are limited when you get beyond cutting, and there’s a good reason for that. The farther you go upstream in precision sheet metal operations, the more similar they become. Visit a massive OEM or the smallest job shop that both use a laser, and you’ll find that both nest parts in a sheet, cut them, denest the cut parts, and dispose the skeleton. Move downstream, though, and operations become vastly different as once-similar sheet metal blanks become disparate. Formed parts aren’t so easy to stack, routing steps become highly varied, holding part tolerances becomes more challenging, and overall complexity rises.

Here, autonomous mobile robots (AMRs) might play an increasing role. At FABTECH 2021, held in September in Chicago, several representatives from the AMR industry participated in a panel discussion about mobile robotics and their interoperability.

“As we acquire new technologies, we need them to work together so we can complete our mission to ensure packages get to our customers. If we don’t have our robots and automation talking to each other, that’s not going to happen.”

So said Aaron Prather, senior technical adviser to Memphis-based FedEx—admittedly, not the first name you think of in metal fabrication. But as Prather said, there’s a reason that FedEx is participating in industry consortiums that promote interoperability, including the Pittsburgh-based Advanced Robotics for Manufacturing (ARM) Institute. “Interoperability goes across all sectors,” Prather said, “from logistics and manufacturing to retail. That’s why FedEx is here at a manufacturing tradeshow.”

“You can build an autonomous mobile robot that can do one type of thing really well,” said fellow panelist Jason Walker, CEO/co-founder of Waypoint Robotics, a Nashua, N.H.-based company that makes a variety of AMRs for transporting tools and materials, even in high-traffic, unpredictable environments. “But no matter how cool our robots are, they don’t have forks. We’re never going to pick up a pallet. Likewise, that pallet robot is never going to be able to slide up to a CNC machine and grab something out of it. The reason you have all these form factors is that each one of them is hard to do at an economical price; they are all made by individual startups. So, if you want to solve all the problems in a facility, you will want to mix and match a lot of different companies. You’ll have a heterogenous fleet.”

Walker’s Waypoint Robotics, Fed Ex, and many others support a group called MassRobotics, a nonprofit that in 2021 released the MassRobotics AMR Interoperability Standard 1.0. “It allows for our robots to be in the same building, understand what the other robots are doing, avoid potential collisions, and unify traffic flow. [The interoperability standard] sets the stage for tons of other capabilities.”

On an individual basis, the capabilities of mobile robotics have increased significantly in recent years. For instance, several years ago Hirotec America, a provider of weld assembly equipment for automotive OEMs, implemented an OTTO Motors AMR to not only carry parts, but also, using a dual-arm Yaskawa robot mounted on top, manipulate parts through a black oxide coating process. (For more on this, see “The potential of self-driving vehicles in metal fabrication.”)

This AMR application focused on one or a handful of manufacturing processes. But imagine a day when automation, both mobile and fixed, works together to adjust to a changing product mix. During one shift, AMRs might bring parts through an oxide coating dipping process. Another day they might use another top module on the AMR to deliver tools to an assembly process. Another AMR with forks could transport boxfuls of assembled sheet metal components to the shipping department.

Pieces of this picture are already real, taking place in individual manufacturing plants for specific applications. True interoperability could bring these pieces together to serve all, or at least most, of a sheet metal fabricator’s wide product mix.