Most multi-rotor aircraft are about as aerodynamic as a brick. Except all its motors are turning and the handle electronics are carrying out their detail, most UAVs are rapidly destined to grow to be UGVs, and frequently in impressive trend. But by switching up points a little bit, it’s attainable to make a multi-rotor drone that retains on flying even with no two-thirds of its motors running.
We’ve been preserving a shut eye on [Nick Rehm]’s awesome spinning drone venture, which basically eschews a rigid airframe for a established of 3 airfoils joined to a central hub. The collective pitch of the blades can be managed by means of a servo in the hub, and the full point can be designed to rotate and deliver raise many thanks to the thrust of tip-mounted motors and props. We’ve noticed [Nick] deal with to get this contraption airborne, and hovering is quite straightforward. The video below handles the upcoming step: acquiring pitch, roll, and yaw manage about the spinning blades of doom.
The problem isn’t trivial. First off, [Nick] experienced to determine what the entrance of a spinning aircraft even suggests. As a result of the clever makes use of of LED strips mounted to the airfoils and some POV magic, he was able to visually suggest a reference axis. From there he was capable to appear up with a plan to range the energy to each and every motor as it moves relative to the reference axis, modulating it in both a sine or cosine purpose to attain roll and pitch handle. This basically imitates the cyclic pitch regulate of a typical helicopter — a kind of virtual swashplate.
The success of all this are amazing, if a bit terrifying. [Nick] obviously has regulate of the plane even even though it is spinning at 250 RPM, but even cooler is the little bit the place he kills very first just one then two motors. It struggles, but it’s even now controllable sufficient for a bumpy but secure landing.