Most industrial robots are far less friendly than the Roomba robot vacuum cleaner, which is safe enough to be a surprisingly popular means of feline transportation. Industrial robots often sit behind metal fences, their mechanical arms a blur of terrific speed and precision; to prevent serious injury to humans (or worse), these robots are normally shut down when anyone enters their workspace.
In recent years, however, the fences have started to disappear as a gentler breed of robot has entered the workplace and new features have made even conventional industrial robots safer to be around. This shift is altering the dynamics of labor in many factories and workshops, allowing humans and robots to work together in efficient new ways.
Human-robot collaboration is “gaining an enormous amount of momentum,” says Henrik Christensen, executive director of the Institute for Robotics and Intelligent Machines at Georgia Tech. “In the past, robots have penetrated 10 percent of the industry. There’s still 90 percent of the industry, and that’s where you need collaborative robots.”
The Robotic Industries Association, a U.S. trade group, last week organized its first conference dedicated to collaborative robots, at which robot manufacturers and customers gathered to discuss the trend. Christensen was a keynote speaker.
The most prominent of the simpler, safer robots introduced in the last few years is Baxter, developed by the Boston-based startup Rethink Robotics (see “This Robot Could Transform Manufacturing”). Baxter, which has two arms and a cartoonish face shown on a touch-screen display, is very easy and safe to work with. To program the robot, a worker simply moves its arms through an operation to show it what to do. And should anyone get in the robot’s way, it will either stop or, at worst, hit the person too gently to leave a bruise. Most important, Baxter is remarkably cheap, costing just $22,000 when many conventional robots cost several hundred thousand dollars.
Another robot maker, the Danish company Universal Robots, offers small, more conventional-looking robot arms that are similarly cheap ($31,000 each), simple, and safe to operate. But these robot arms also offer greater precision and programmability, meaning they can perform complex work and either step in for a human worker or work alongside one. They can quickly be repurposed for a new job without requiring much reprogramming.
Edward Mullen, national sales manager for Universal Robots, says the company has sold around 2,500 robots since launching in 2009, and he estimates that 80 percent are running unguarded. Many of the robots have been sold to small or medium-sized companies that do not otherwise use robots. RSS Manufacturing, a company in Costa Mesa, California, that produces custom automobile and plumbing components, uses Universal Robots machines for jobs including manipulating pipes in a tube bender and producing valves on a milling machine. The company’s production runs can be as short as 24 hours, so the robots have to be swapped quickly between different tasks. None of the robots are placed behind safety fences.
There’s still plenty of work that’s too arduous or precise for Baxter or Universal Robots’ machines. But more powerful conventional robots are starting to work in closer proximity to humans, too. New sensors and software allow these machines to predict collisions and avoid them as humans go about their work.
Kuka Robotics, an industrial-robot manufacturer with headquarters in Germany, is testing robots equipped with such safety systems. “Fences are expensive, and it takes time to work in and around the fences,” says Stuart Shepherd, CEO for the Americas at Kuka. “Then there are some applications that don’t work unless you have man-machine collaboration.”
Shepherd says some manufacturing tasks, such as the production of small transmission components, may require a robot to do the physical labor while a person performs quality-control inspections after each component is made. That requires the human and robot workers to operate side by side. For other jobs, like lifting an engine block so that it can be worked on, a human can activate a “lift-assist” mode on certain Kuka arms and then use the arm to do the heavy lifting. In this case, it would take too long to reprogram the robot to do such a one-off job.