The three laws of robotics, according to renowned science fiction writer Isaac Asimov (including his seminal 1950s-era collection “I, Robot”) start with: “A robot may not injure a human being or, through inaction, allow a human being to come to harm.”
The same mandate applies to collaborative robots, aka cobots. In fact, improved safety is one of the main purposes and advantages of such machines.
An operator demonstrates the ease of use and programming of ABB’s GoFa cobot.
Cobots incorporate multiple safety features allowing them to work side-by-side with human operators in a shared workspace, eliminating the need for costly physical barriers. They are often used for repetitive tasks that are too dangerous, strenuous or tedious for humans to do on their own.
Cobots are an ascendant technology promising many of the advantages of traditional industrial robots along with easier use, more intuitive programming and, most notably, greater safety.
Some of the primary uses for cobots include:
- Assembly
- Material handling
- Quality inspection
- Machine tending
- Palletizing
- Painting
- Welding
Due to safety concerns with humans in the workspace, however, cobots typically run at 10-20% of their maximum speed—though they can run at full speed when humans aren’t there—and they typically have a limited payload. In some cases, humans may only need to be present intermittently, such as for loading parts and performing inspections, and may even be out of the work area most of the time allowing the cobot to run at full speed when safety considerations allow, so as not to sacrifice throughput.
Let’s be Friends
Cobots not only are designed to be user-friendly for operators working directly with them, but they also can be easier to interact with across the manufacturing ecosystem. “The focus now on the benefit of cobots is that they are also easier to install and quicker to deploy,” explains Andie Zhang, global product manager for ABB Group. “And they have a much smaller footprint compared to large industrial robots.”
Their ease of deployment and use of floor space make them that much more user-friendly for both the integrator and top-level plant management. “Our customers want lean robots that are easy to use and that can be installed without large physical fencing, and cobots are safe to work alongside people,” Zhang says. And there are additional needs being met better by cobots than by traditional industrial robots. “A lot of manufacturers have deployed automation for the high-volume, low-mix production parts,” according to Zhang, “but now they’re trying to solve the next set of challenges including higher-mix, lower-volume production…The timelines and product life cycles are changing so automation needs to adapt and become more flexible,” But, she cautions, there could be additional risks, depending on the tooling mounted on the cobot and what kind of workpiece it’s holding, as well as the type of application being performed.
FANUC CRX-20iA/L Food-Grade Cobot uses a bakery tray to catch cookies coming off the end of the conveyor and place the full trays onto a cart in this bakery demonstration.
Chris Savoia, who heads ecosystems in the Americas for Denmark-based Universal Robots A/S, takes the idea of cobot friendliness a step further. “Universal Robots has a software development kit, Motion Plus, available for users to write apps for their cobot much like you can write an app for a smartphone. These apps allow you to extend the functionality of our robots and cobots to work with other products.” And, he adds, for higher-level shop managers, “we make it easier by allowing them to just go through a distributor rather than having to go through an integrator. The cobots’ ease-of-use and ease-of-integration allows that.”
In general, cobots are significantly smaller and lighter than other industrial robots, allowing for a much smaller footprint—including, in some cases, tabletop mounting. The fact that they do not require safety gates and fencing to isolate them for safety, greatly reduces the floorspace required as well as the overall capital expense incurred by the additional equipment, proponents note.
Japan’s FANUC Corp., which has been at the forefront of automation since the company’s inception in 1958, now has more than 40 million installed automation products worldwide—including a growing number of cobots.
“We’ve had a million robots installed as of June of last year and we took that long history of robots and developed a collaborative version of that industrial-style robot,” notes Jerry Perez, FANUC America Corp.’s executive sales team manager. “Then in 2019, we released our latest collaborative robot series called the CRX Robot Series.”
The CRX Robot Series, according to Perez, has a design that is in line with what the trends are in the marketplace, including being lightweight and running on 110-volt AC power.”
Integrators and shop floor managers alike are often pleasantly surprised by the smaller footprint offered by cobots.
Building Trust
While trust isn’t one of Asimov’s laws of robotics, it’s critical for working with cobots. A study in the Journal of Intelligent Manufacturing (JIM) in 2023, which defines trust as “how much workers feel comfortable working with collaborative robots and the extent to which they feel they will be able to accomplish a task through interacting with them,” points to sources that seem to promote the idea that trust, while already relatively high, is increasing.
“People are about touching things, interacting with things,” Savoia asserts. “They’re about the physical and they’re working next to [the cobot] every single day. So they are the ones who are oftentimes the harshest judges. But that’s where we win the most.
“Traditional industrial robots are very fixed and hard to integrate with vision,” he continues. “It used to really take an expert to do it. But now, major companies have lowered the barrier on that so much that you can be an operator and a programmer. Say you’ve got a new process that got set up in a facility. An operator can take that and train a few more images and the cobot can take over and do the job. Previously, that would have required an automation engineer to come in and change the whole algorithm.”
For example, Savoia says, operators can now use cobots to set up their own pallets and make changes on the fly. “The cobots adapt to the changing reality of their work just like a human would, without needing to stop and call somebody over every time they got a new box in front of them.”
As modern cobots are typically equipped with additional sensors, they not only can detect nearby people, they also have a better sense of everything in the workspace, including parts and pallets, leading to greater flexibility. Additionally, the recent introduction of artificial intelligence (AI) algorithms allows some cobots to learn from errors, which means cobots can be taught once, and they’re useability, productivity and the quality they output over time increases, according to JIM.
ABB says its OmniVance machine tending cobot simplifies machine tending.
Limiting Factors
As promising as cobots seem to be, they are not cure-alls. A few of the biggest limiting factors that must be considered, versus traditional industrial robots, are payload, speed and precision.
Noting that cobots are typically “human scale,” UR’s Savoia, says they can be expected to handle payloads similar to the capabilities of their human counterparts. This equates to about 55 lbs, according to OSHA guidelines.
“So it’s like a 30-kg robot, plus the end effector,” Savoia says. “And we are roughly the speed that a very fast human would be working. We’re not going to be lifting up an entire car, and we are not going to be running so fast that it’s a blur.”
Current limits such as speed and those stemming from environmental factors, are constantly being expanded, adds ABB’s Zhang. “We have developed, together with the market, cobots capable of working even in dirty environments with a lot of dust, grease, etc. We have IP67-rated cobots and that was a requirement we did not think was needed in the early stages of development.
Cobots such as the one pictured here from Universal Robots, feature rounded edges and a variety of other safety features.
“At first, we had a low IP-rating because we imagined the cobot would be working in a very clean environment,” Zhang continues. “Now there is a focus by the users on speed and that cobots should be very productive as well. So speed is becoming important and additional features like force control and features to work with welding software.
“These are features previously associated with industrial robots but now they are starting to move into collaborative robots as our customers are using cobots for these types of applications.”
Flexibility and Precision
Cobots can be a good option where flexibility is needed, including a mix of automation. For example, they are smaller and leaner and work very well in slower speed applications such as palletizing lines.
“When you automate with an industrial robot, you have to automate 100% of the task; but with collaborative robots you can automate only the parts of the task that are difficult or dangerous for a human operator and the human can do the rest,” ABB’s Zhang says. “Many tasks are both very difficult and very expensive to automate completely and cobots help to reduce this burden.”
Another type of flexibility comes with a cobot’s capacity to be reconfigured, either for changes that come along for their assigned job, or for repurposing for an entirely new task. In some instances, lighter-weight cobots are mounted on mobile carts that can be easily moved between different workstations to perform different functions. This reconfigurability, i.e., the ability to be quickly and easily re-programmed to meet changing market requirements, makes manufacturers more efficient and significantly more nimble.
With reconfigurable manufacturing systems (RMS), manufacturers can shift production between models and products more quickly, as well as allow them to integrate new production processes. This is especially important in the modern marketplace where product life cycles seem to get shorter and shorter making the need to quickly introduce new products that much more urgent.
Tradeoffs
Such flexibility afforded by cobots allows manufacturers more options to get jobs done in the manner that works best for them. To some potential users, however, greater flexibility doesn’t outweigh a perceived lack of precision with cobots.
Many sources point out that cobots are not well suited for very high-precision tasks, perhaps due to their so-called human scale. Hand guidance, for example, greatly simplifies and speeds up the programming process, but does not afford the same precise programming one can achieve with traditional robotic arms.
But the perception of cobots’ lack of ability for very precise tasks is also changing. In 2024, ABB launched something called Ultra Accuracy, claiming the mantle of the most accurate cobot on the market with extremely high pass accuracy, according to Zhang. These cobots also reportedly provide extremely high position accuracy capable of targeting even high-accuracy applications.
Kuka‘s lightweight LBR robot features a simple interface andhand-guiding features.
Medical Attention and Other Applications
Germany’s KUKA AG also has been a major player in industrial automation, with origins dating back more than 100 years. And, in recent decades, the company has contributed to the surge in cobot use across multiple industries.
“In medical robotics, we’ve had patients on robots and patients being treated by robots in very close proximity,” says Corey Ryan, director of medical robotics for KUKA Robotics Corp., Shelby Township, Mich. “Presently we have machines that are specifically cobots and we sell other industrial robots that are adapted to work in collaborative spaces.”
Ryan is optimistic about the growth of cobot use and further development in medical, as well as across many other fields. One potential big area he points to is autonomous mobile robots. “Mobile platforms driving around factories and manufacturing facilities carrying a collaborative robot arm and doing multiple tasks within that same workspace is a high growth area—taking the cobot on the move within the factory,” he says, adding that these trends likely will continue as cobot acceptance and familiarity continue to grow.
“You’re starting to see more of the really low-cost cobots that are simple and easy to program, and you’re seeing some more of the advanced ones,” Ryan says. “The more advanced ones have bigger software packages and more pre-canned features. “For example,” he continues, “KUKA has the LBR iisy [leichtbauroboter—German for lightweight robot], which has a very simple interface; mostly ROSS [robot operating system] programming with a few features like hand guiding. But it really is a stripped-down robot open to whatever people want to use it for.”
Prior to the COVID-19 pandemic, there was more resistance to automation. Since then, the worry that “robots are taking our jobs” has subsided with the ongoing workforce shortage.
“What’s happening in factories now, is they need 200 people to make the factory run and they can only get 160,” Ryan says. “So they are coming to integrators and robot manufacturers and saying ‘What can I automate?’
“They’ll take people on the shop floor and promote them up the chain because what they need to automate are the simple basic jobs,” he continues. “So people are no longer saying robots are taking their jobs, but instead are saying that robots and cobots are helping to keep the factory here. If we can’t automate, those factories are going overseas.”
Plus, the ease of use and programming that cobots afford is more important now than ever. “Even with our largest manufacturers, who’ve had 30 years experience deploying robots,” FANUC’s Perez adds, “the talent and skillsets who’ve been operating them and maintaining them, they’ve retired.”
This furthers the case for cobots. Although they are unlikely to replace most of the bigger industrial robots anytime soon, they will continue to make inroads in the manufacturer’s arsenal.
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