FLYING ROBOTS THAT CHANGE SHAPE

Scientists at the University of Washington have developed flying robots that change shape in mid-air, all without batteries. These miniature Transformers snap into a folded position during flight to stabilize descent.

They weigh just 400 milligrams and feature an on-board battery-free actuator complete with a solar power-harvesting circuit. The origami-inspired design allows them to transform quickly from an unfolded to a folded state, a process that takes just 25 milliseconds.

This transformation allows for different descent trajectories, with the unfolded position floating around on the breeze and the folded one falling more directly. Small robots are nothing new, but this is the first solar-powered microflier that allows for control over the descent, which consists of an onboard pressure sensor to estimate altitude, an onboard timer and a simple Bluetooth receiver.

The current design only allows them to transition in one direction, from the tumbling state to the falling state, but researchers can control multiple microfliers at the same time, making them disperse upon launch to cover a wider area.

They are working on perfecting the reverse transition to allow the robots to transform back from the falling position to the folded position, which should better allow the microfliers to make precise landings even in turbulent wind.