Insect-sized flying robots could help with time-consuming tasks like surveying crop growth on large farms or sniffing out gas leaks. These robots soar by fluttering tiny wings because they are too small to use propellers, like those seen on their larger drone cousins. Small size is advantageous: These robots are cheap to make and can easily slip into tight places that are inaccessible to big drones. But current flying robo-insects are still tethered to the ground. The electronics they need to power and control their wings are too heavy for these miniature robots to carry. Now, engineers at the University of Washington have for the first time cut the cord and added a brain, allowing their RoboFly to take its first independent flaps. This might be one small flap for a robot, but it's one giant leap for robot-kind.
RoboFly is slightly heavier than a toothpick and is powered by a laser beam. It uses a tiny onboard circuit that converts the laser energy into enough electricity to operate its wings. The engineering challenge is the flapping. Wing flapping is a power-hungry process, and both the power source and the controller that directs the wings are too big and bulky to ride aboard a tiny robot. But a flying robot should be able to operate on its own. They decided to use a narrow invisible laser beam to power their robot. They pointed the laser beam at a photovoltaic cell, which is attached above RoboFly and converts the laser light into electricity. A circuit boosted the seven volts coming out of the photovoltaic cell up to the 240 volts needed for flight. To give RoboFly control over its own wings, the engineers provided a microcontroller to the same circuit.