CREDIT: DJ PRESTON, P ROTHEMUND, HJ JIANG, MP NEMITZ, J RAWSON, Z SUO AND GM WHITESIDES
The American researchers really put the "soft" in "soft robot". They built one out of rubber and air.
There is not even any conventional electronics. Silicone tubes and pressurized air do this job. According to Daniel Preston of Harvard University, the invention could allow operators to "reproduce any behavior found on any electronic computer".
In the case of the fish-like robot, created by Preston and his colleagues, an environmental pressure sensor determines the action to be taken.
Flexible valves are programmed to react to different air pressures. The robot plunges when the circuit detects a low pressure at the top of the tank and at the surface when it detects a high pressure in depth. It may also appear on command if someone presses an external programmable button.
In other words, says Preston, it relies exclusively on digital software logic – and this is a first.
The how and why are explained in an article published in the journal PNAS.
Controlling robots without electronics is not new. The authors note that others have designed microfluidic circuits that use liquid and air to create non – electronic logic gates.
The problem, they say, is that circuits often rely on hard materials such as glass or plastic and use channels as thin as small amounts of air at a time, which slows the robot's motion .
In comparison, the channels in Preston's design are wider, allowing for much faster airflow rates. The aerial forceps that he has created can grab an object in seconds.
HI circuits are also more efficient because they do not require any standby power input. This could be critical, he suggests, in emergency situations where robots move away from a reliable source of energy.
They could even become essentially invisible if they were made from a matching material in the background.
Virtual robots are increasingly part of the world of metal-dominated robots over the past decade, as they have many advantages in many contexts.
For Preston and his colleagues, the use of rubber adds valuable simplicity to work using machine learning and artificial intelligence.
"There are a lot of abilities out there," he says, "but it's also good to step back and ask yourself whether or not there's a simpler way of doing things that give the same result, especially if it is not only simpler, also cheaper. "