Flying bird robot can soar so well it uses almost no power

A flying robot can float on gusts of wind like a bird, using 150 times less power than it does during propelled flight. It can also adjust its position automatically when the wind changes to catch the breeze and stay aloft.

The main limit on how long a drone can stay in the air is the lifetime of the battery it uses to power its propellers. To save energy, researchers have experimented with drones that soar upwards or …