Robotic dragonflies could be the next explorers on Mars, and a new design is already buzzing around on Earth. Developed by Festo, the mechanical insect exploits the unique mechanics of four-winged flight, allowing it to fly in all directions, hover in mid-air and glide without beating its wings. Each wing's motion can be fine-tuned by controlling its amplitude, flapping frequency and thrust - which is achieved by adjusting its tilt and twist. The team says a smartphone can act as a remote control to put the dragonfly almost anywhere in a given space. Although it appears to be considerably larger than a real dragonfly, the robot is light thanks to a carbon-fibre frame and flexible polymer shell. That structure holds a microcontroller, mechanical components, sensors and wireless modules, showing how different functions can be integrated and miniaturised.