You might remember RoboBee, an insect-sized robot that flies by flapping its wings. Unfortunately, though, it has to be hard-wired to a power source. Well, one of RoboBee’s creators has now helped develop RoboFly, which flies without a tether. Slightly heavier than a toothpick, RoboFly was designed by a team at the University of Washington — one member of that team, assistant professor Sawyer Fuller, was also part of the Harvard University team that first created RoboBee. That flying robot receives its power via a wire attached to an external power source, as an onboard battery would simply be too heavy to allow the tiny craft to fly. Instead of a wire or a battery, RoboFly is powered by a laser. That laser shines on a photovoltaic cell, which is mounted on top of the robot. On its own, that cell converts the laser light to just seven volts of electricity, so a built-in circuit boosts that to the 240 volts needed to flap the wings. That circuit also contains a microcontroller, which tells the robot when and how to flap its wings — on RoboBee, that sort of “thinking” is handled via a tether-linked external controller.