Smooth control of an X4 bidirectional rotors flying robot

A particular structure of a four rotors mini-flying robot where two rotors are directional (X4 bidirectional rotors) is presented in this paper. The two internal degree of freedom leads to a transformation between the equivalent system of the control-inputs and the rotor force-inputs which is not a diffeomorphism. This makes our system different from that of the classical flyer robot (X4 flyer). The dynamic model involves five control inputs which will be computed to stabilize the engine with predefined trajectories. A path-like flying road, described as straight-lines with rounded corners permits to prove the effectiveness of the proposed static feedback control law.