PITTSBURGH, Pa. -- Inspired by the way beetle larvae wiggle to move across water, researchers at the University of Pittsburgh have developed a low-energy and low-maintenance system for moving small robots and boats in water.
The system, which uses electrical pulses in place of paddles, sails and motors, is designed for small boats and devices that monitor the water quality in reservoirs, oceans and other bodies of water. Such devices usually rely on propellers to move about.
Senior researcher Sung Kwon Cho was inspired to devise the system after reading about how beetle larvae make their way through water. Cho is also a professor of mechanical engineering and materials science in the university's Swanson School of Engineering.
To move across water, beetle larvae start off resting on the water, causing the surface tension to pull equally on all sides. To move forward, the beetles bend their backs downward, causing the tension behind them to change and the forward tension to pull them, using the energy within the water's surface to move them forward.
The electrical pulse system does the same thing, destabilizing the surface tension on one side or multiple sides of a small boat to propel it in the opposite direction or, as shown above, in a circle. In the above display, two electrowetting-on-dielectrics (EWOD) electrodes - indicated by the red circles - generate pulses, causing the boat to rotate.
The system has no moving parts, and the low-energy electrode that emits the pulse can be powered by batteries, radio waves or solar power.Original here