Microbots that can hitch-hike on birds, butterflies

                Harvard scientists have developed flying micro-robots that can use static electricity to perch on bats, birds or butterflies to conserve energy in long-duration flights. “Many applications for small drones require them to stay in the air for extended periods,” said Moritz Graule, who conducted the research as a student at Harvard University.

                “Unfortunately, smaller drones run out of energy quickly. We want to keep them aloft longer without requiring too much additional energy,” said Graule. “A lot of different animals use perching to conserve energy, but the methods they use to perch, like sticky adhesives or latching with talons, are inappropriate for a paperclip-size microbot, as they either require intricate systems with moving parts or high forces for detachment,” said Kevin Ma, from Harvard.

                The team turned to electrostatic adhesion. “In our system, a small amount of energy is constantly supplied to maintain the attraction,” he explained. The RoboBee uses an electrode patch and a foam mount that absorbs shock. The entire mechanism weighs 13.4 mg, bringing the total weight of the robot to about 100mg. It take off and flies normally. Ehen the electrode parch is supplied with a charge, it can stick to almost any surface, from glass to wood to a leaf.