Wind-cheating Morpho combines qualities of copters and fixed-wing drones
Both multicopter and fixed-wing drones use up a lot of battery power when fighting the wind. The Morpho VTOL (vertical takeoff and landing) drone addresses this problem with morphing wings that adapt to lessen its wind resistance. In fact, they can even use the wind to the aircraft's advantage.
Currently in functional prototype form, the Morpho is being developed by Swiss startup Elythor. That company is in turn a spinoff of the EPFL research institute.
The drone features an aerodynamic bullet-shaped body with four quadcopter-style propeller arms, along with four wings. Each wing can pivot independent of the main body.
When on the ground, the aircraft sits in a vertical orientation with its wings angled downward to hold it upright (sort of like a four-legged tripod). It then takes off vertically like a quadcopter, using feedback from onboard sensors to adjust the angle of each wing so that it catches as little crosswind as possible.
That said, if the Morpho needs to move in the direction in which the wind is blowing, it adjusts its wings to catch the wind – it's essentially utilizing them as sails, instead of using battery power to vary its thrust.
Once it's time to enter "fixed"-wing forward flight, the drone tilts into a horizontal orientation, moving its wings into a biplane-like configuration. If it subsequently encounters crosswinds coming at it from an angle while en route, it can put its wings into an asymmetric orientation which compensates for the off-center wind resistance.
"The controller automatically selects whether to hold the wings in place or let them move freely with the wind, based on the drone’s trajectory and effective speed, along with any changes in wind direction," said Elythor cofounder Nathan Müller. "The wings’ surface area can also be adjusted either symmetrically or asymmetrically depending on wind direction."
It is hoped that the Morpho could ultimately be used in the inspection of things like power lines, power plants, wind turbines and offshore oil platforms. Because its wings can be drawn in close to its body when it's hovering, it could move in very close to obstacles while performing its inspections. Moving between inspection sites, it could switch over to faster and more energy-efficient fixed-wing flight.
"Winged drones have the advantage of longer flight times, while quadcopters have better manoeuvrability," says Elythor CEO/cofounder Harry Vourtsis. "We combined the two and added an adaptative wing system that reduces the drone’s power requirement even further."
The Morpho drone can be seen in action, in the video below.