University of California at Riverside (UC Riverside) engineers have created what they describe as "air-powered computer memory," which drives a robot — dubbed, amusingly, "Airhead" — to play the piano.
"Pneumatically-actuated soft robots have advantages over traditional rigid robots in many applications," the researchers write in the abstract to their paper. "In particular, their flexible bodies and gentle air-powered movements make them more suitable for use around humans and other objects that could be injured or damaged by traditional robots."
"However, existing systems for controlling soft robots currently require dedicated electromechanical hardware (usually solenoid valves) to maintain the actuation state (expanded or contracted) of each independent actuator. When combined with power, computation, and sensing components, this control hardware adds considerable cost, size, and power demands to the robot, thereby limiting the feasibility of soft robots in many important application areas."
The solution — which UC Riverside has likened to a step towards a fully-pneumatic robot like Baymax from Disney's Big Hero 6 — is pneumatic logic, literally creating "air-powered" memory inspired by player pianos and thermostats from the early 1900s.
The resulting eight-bit RAM chip uses microfluidic valves where traditional computer memory uses electronic transistors, creating pressure differentials to control the location of actuators — even when cut off from their air supply. Air pressure equals a binary 0, while a vacuum represents a 1 — and while eight bits isn't much, it's enough to have a 3D-printed robot play the piano.
"By dramatically reducing the amount of hardware required to control multiple independent actuators in pneumatic soft robots," the team writes, "our pneumatic RAM can accelerate the spread of soft robotic technologies to a wide range of important application areas."
The work has been published in the journal PLOS ONE under open-access terms.