Modelling and Control of a 5DoF Tilting Quadrotor

The inherent underactuation of standard multirotors has led to the development of new platform designs, especially for physical aerial interaction. This paper presents the modelling and control of a tilting quadrotor, which includes tilting motors actuated by two servomotors. This design allows independent control of the pitch angle and the x-axis position by the reorientation of the motors. In this paper, we derive the dynamics of the aerial robot in a state-space representation, including its allocation matrix. This model is compared with that of an underactuated quadrotor, showing the possibility of controlling the pitch angle and the x-axis position in an independent way. For controlling the tilting quadrotor, the standard PID-cascade controller of an underactuated quadrotor is adapted for the platform with servomotors. Finally, the controller is validated through extensive simulations. The proposed model and controller serve as a first step in the development of a 5DoF tilting quadrotor. Video available at https://youtu.be/eXVDa9SZGlQ.