Quadrotor with a Dihedral Angle: on the Effects of Tilting the Rotors Inwards

We study the effects of tilting the plane of rotations of the rotors of a quadrotor helicopter inwards, a structure inspired by the dihedral angle in fixed-wing airplanes. We show that this configuration yields effects that contribute to stability and reduce the dependency on velocity measurement which, in many cases, is hard to achieve at sufficient rate and accuracy. We present a theoretical analysis supported by simulations and by experiments.