Insects are true masters of flight – small, lightweight and highly manoeuvrable.
Scientists have been taking inspiration from our six-legged friends
to try and create flying robots of the same size.
But it's proven difficult because when you get down to the insects' scale,
it's hard to generate enough thrust to carry your own power source.
But there's a new robot in town that's creating a bit of a buzz.
This is RoboBee X-Wing.
It's got a wingspan of just 3.5 centimetres and it's about a quarter of the weight of a paperclip.
At this scale, batteries are just too heavy to be carried onboard,
so the researchers used ultra-lightweight solar cells.
These generate power and send it to a control board that operates a pair of piezoelectric actuators –
clever materials that work a bit like a muscle and contract when a voltage passes across them.
By sticking two actuators together, they bend back and forth to flap the bot's wings.
These seminal flights lasted for less than a second
and required more than twice the energy contained in sunlight.
But they represent an important milestone for flight at this scale,
and even supersede the thrust efficiency of living insects.
There's certainly still room for improvement.
The aerodynamics of the wings are not as efficient as a real insect's,
and, of course, the controls that insects pack into their tiny compact brains
are a long way off for RoboBee X-Wing.
But this model produced more thrust than it needed and in the future,
that could be used to carry controls, sensors, maybe even some sort of battery.
The hope is that these miniature robotic insects will one day be able to achieve continuous outdoor flight
and help with environmental and disaster monitoring,
perhaps even operating in a swarm.