A mother robot built her own robot children, improving them with each successive generation — all with virtually no human intervention.

Mull that over for a minute.

The robotics breakthrough, reported this week in the open access journal PLOS One, happened when researchers at University of Cambridge programmed a specially equipped Universal Robots UR5 robotic arm and gripper to not only build a robot capable of movement, but to use information gleaned from the performance of the mother robot's first children to progressively more successful ones.

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This act of building better and better robots based on the best traits of the original is, the researchers claim, a form of evolution.

In a release on the project, lead researcher Dr. Fumiya Iida of Cambridge’s Department of Engineering, who worked in collaboration with researchers at ETH Zurich, explained, “Natural selection is basically reproduction, assessment, reproduction, assessment and so on. That’s essentially what this robot is doing — we can actually watch the improvement and diversification of the species.”

What mama robot has built, though, is not exactly C-3PO. The robot babies are six centimeter, 3D-printed blue boxes equipped with a single motor. The robot mother used glue to connect one motorized cube to another. Once the baby bots are built, the computer would use the camera to analyze the baby robot's movement and deliver that information back to the robot mother which would then use that information to modify its design by changing one or more program elements or "genes" within the cubes and, ultimately, birth better mobile robot cubes.

The way the robot mother builds its robot babies is described by researchers as the "genome" part of the creation process. In other words, it's how the mother robot imprints on each baby. That imprinting is part of the developmental process, Iida told Mashable.

There were some building constraints to avoid structures that couldn't function in the real world. So any design that lacked a motor, proved too heavy or included movements where one motor would cause a collision with another robot part — thereby making the baby robot immobile — were weeded out before Mama Robot could build them.

Not every baby is beautiful. This is one of the robots Cambridge University's mother robot built. Image: Cambridge University

It's also worth noting that what we're witnessing here is not, technically, generational evolution. "In this case the generation is a little bit misleading," agreed Dr. Fumiya, "a child robot never becomes mother robot." Instead, it's a sort of hyper-inter-generational evolution, all occurring within one little robot family. In the end, the team let the robot mom build 10 generations (100 robot babies) and then ran the experiment five times (500 robot babies!). Each build took about an hour and the entire project stretched over the course of four years.

The researchers claim that not only did the robot mom build better moving children, it cooked up configurations that might never have occurred to humans.

What will we do with evolutionary robots? "What we’re interested in from [a] robotics perspective, is that robots are not creative at all. They're stuck in factories," doing the same things over and over again, said Iida. The Cambridge researchers wonder if these more creative or adaptive robots can have broader applicability in industries like construction where, even if all the homes are the same, the ground is different.

"Human builders have to deal with it. We wonder how our construction process in a robot can be applied to a house-building process, to make cheaper and faster houses in the future," Iida said.

As for fears about robots building an army of smarter and smarter robot children, Fumiya did not dismiss them. “Any new technology can be dangerous. Every new technology has a good aspect and a bad aspect. Maybe in 50 years it'll be dangerous, but we’ll figure it out before that."