A system uses combustion to inflate silicone membrane “dots,” which could someday serve as a dynamic braille display for electronics.
Imagine a tablet or Kindle that can display braille on command for the visually impaired. The major hurdle in designing the dynamic display is how to apply the necessary amount of force to raise each popup dot. This system is composed of molded silicone and microfluidic liquid metal traces, in which liquid metal electrodes cause a spark to ignite a microscale volume of premixed methane and oxygen. This fuel flows through a series of independent channels, each leading to a 3-millimeter-wide actuator. The rapid combustion forces a thin silicone membrane at each site to inflate several millimeters. A magnetic latching system gives these dots their persistent form, and the whole system can be reset simply by pressing them down. Because there is no need for electromechanical valves, the actuators can be packed more densely together, resulting in a smaller, potentially portable system that still manages to produce large displacements at high force in under 1 millisecond. Since the flu-idic elastomer actuators cool quickly, and so little fuel is required, a commercial version could be safely operated.
Cornell University, Ithaca, NY, and Technion-Israel Institute of Technology.
Earlier attempts have involved motors, hydraulics, or tethered pumps, all of which are cumbersome, complex, and expensive. Using combustion, small volumes of gas can create a powerful outcome.
The current system consists of nine fluidic elastomer actuators, but the researchers are hoping to scale that up and eventually create a full electronic tactile display. The stretchable technology could also be used for soft robots, surgical tools, and wearable VR equipment.