Multirotor drones are significantly more popular than conventional helicopter designs for many reasons, which do not include efficiency. Making use of the aerodynamic effects behind this, [Nicholas Rehm] was able to significantly increase the efficiency of his experimental tricopter by turning it into one large spinning propeller.
Since aerodynamic drag is proportional to velocity, a small, high-RPM propeller will require more power to produce the same thrust as a large, low-RPM propeller. With this in mind, [Nicholas] built a tricopter that can rotate all three long arms together using a single servo, giving it very aggressive yaw control. By attaching a wing to each of the arms, it becomes a large variable pitch propeller powered by tip thrusters.
To measure the efficiency of the craft, a small lidar sensor was added to allow accurate PID altitude control. While keeping the drone at a constant altitude a few feet off the ground, [Nicholas] measured the power draw of the…
