Skip to content

A helicopter blade uses a swash plate and a set of linkages to change the angle of the blades. Not only does it vary the collective pitch to increase or decrease thrust, but it varies each blade’s pitch throughout each rotation, letting it produce more lift on one side of the rotor. This presented a problem to [worked in theory] — he’s building an RC helicopter from scratch, and this mechanism added both complexity and weight. Instead, he started looking for a way to get around the problem .

There were two options to eliminate the linkages: a linkage-less swashplate design used in Black Hornet drones, and an under-actuated design using angled hinges to control the blade angle. [worked in theory] started with the Black Hornet design, which has the end of each blade run along the swashplate on wheels, while a central spring presses them down. Friction in the hinge and wheels proved too high, and it stopped responding at higher speeds.…