Methanol fuel gives this tiny beetle bot the freedom to roam
A robot beetle goes the distance on its own thanks to a methanol-fueled micromuscle. Scientists envision that swarms of robotic insects could assist search-and-rescue operations (SN: 5/19/16). But tight spaces are out of reach for robots that must be tethered to an energy source. The new bot, described August 19 in Science Robotics, carries its liquid fuel inside its body. “I realized the critical issue was power,” says Néstor O. Pérez-Arancibia. His team at the University of Southern California in Los Angeles turned to methanol because in a given mass, it packs over 10 times the energy as tiny batteries. To turn methanol into motion, the researchers coated a nickel-titanium alloy wire with platinum. The alloy contracts like a muscle when heated, and extends once cool. The platinum generates heat by combusting any methanol vapor that comes in contact with it. By varying the exposure to fuel in a periodic pattern, the temperature...