THOR Transformer Drone Can Hover and Cruise Equally Well

Small drones tend to come in two distinct varieties: the ones with wings, which are best for carrying loads over long distances; and the ones with rotors, which are more agile but less energy efficient. A few drone-makers have tried to combine both flight-modes into a single design, but none have taken the approach of THOR — a new drone from the Singapore University of Technology & Design.
 
Usually, when aircraft makers want to hover and cruise, they simply fix rotors onto rotating wings, like NASA did with its massive Greased Lightning prototype. But with THOR (it stands for Transformable Hovering Rotorcraft) the wings become rotors, transitioning in mid-air and spinning around a central module like a single-bladed helicopter. The end-effect makes the craft look like a sycamore or ‘helicopter’ seed, which use the same design to disperse themselves away from their trees. The drone’s creators, who presented their work at the ICRA conference last month, say they were actually inspired by the similar-looking samara seed.
 
The design of the drone still needs a bit of work, as transitioning from one mode to the other isn’t seamless. But speaking to IEEE Spectrum, THOR’s creators are confident it can find an edge over current drone designs: “Because [...] it can be made smaller than other hybrid platforms, [it] will unlock many possibilities where current hybrid UAVs are too big or bulky to operate! These include agriculture, surveillance, and package delivery, all of which are hot topics in drone development as of the moment.”

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