Video Shows a New Rubber Computer That May Hold the Key to Invisible Robots

Robotics has been a world dominated by metal until now.

Robotics has long been a world dominated by metal — until now. Scientists have developed a new kind of completely soft robot, devoid of any hard or electronic parts, in a development that carries far larger implications than just being really, really huggable.

In addition to making robots safer to collaborate with, completely soft robots will also be more resilient in disaster zones or areas with high radiation. Most excitingly, overcoming the need for hard electronic parts may open the door to robots built with index-matching materials that blend in with their surroundings thanks to a shared index of refraction. Translation? Invisible freaking robots. The findings were published today in the PNAS journal.

Led by Daniel J. Preston and funded in part by the U.S. Department of Energy, the study introduces a new kind of soft computer made from silicon tubing and pressurized air, eliminating the final metal bits that have lingered in “soft” robot models over the past decade. Currently, many soft robots come in the form of “grippers” used for handling delicate products. Their design already relies on simpler control methods, and their inability to cause serious damage means a simple on/off switch often suffices. But key elements — mainly, the computer boards and valves that control air flow — continue to be made up of hard, often metal parts.

“[Soft robots] are currently controlled by electronic computers and hard solenoid valves, limiting their application in areas of high radiation—for example, near nuclear disasters, or in MRIs—and preventing them from being completely soft to avoid damage,” head researcher Preston tells Inverse. “We set out to circumvent these problems by enabling onboard decision-making with an entirely soft, air-powered computer.”

A semi-autonomous submersible robot measures water pressure with a soft computer. The robot dives when it senses low pressure (near the surface) and rises when it senses high pressure (at depth). The robot also surfaces on command at the touch of an external button.

Preston’s design mimics the “thought process” of a computer, but replaces electronics with pressurized air. This new soft computer utilizes the same “logic gate” theory that digital computers have used for years — a circuit board receives a message (input) and determines a response (output) — but its valves have been programmed to respond to various air pressures instead. In the video above, the soft robot senses low pressure near the surface, and responds by diving; the opposite happens once it senses high pressure at the bottom of the tank.

Why the drive toward fully soft robotic models? When utilized in industrial settings, soft robots prove significantly safer for their human co-workers. Get in the way of the big, fast-moving, “blindly” operating machines that drive production for automobile factories, for example, and you run the risk of serious injury. When all you’re contending with is rubber and air, the stakes are much lower. Additionally, soft robots are cheaper, lighter and more durable than their metal-bound counterparts.

“If it gets run over by a car, it just keeps going,” wrote Preston in his team’s press release.

A total lack of metal also means that soft robots can venture into areas with high radiation, like MRI machines and natural disaster sites. But arguably the most exciting prospect of soft robot innovations? Preston currently hopes to experiment with a variety of “elastomers” (rubbers) that are index-matched to their surroundings. The result? “Completely transparent soft robots with onboard memory and decision-making.”

Should Preston choose a substance that’s “camouflaged” in water, for example, he could build an autonomous robot that’s invisible to the naked eye.

Media via D.J. Preston, P. Rothemund, H.J. Jiang, M.P. Nemitz, J. Rawson, Z. Suo, and G.M. Whitesides,