Hidden and transient chaotic attractors in the attitude system of quadrotor unmanned aerial vehicle

Currently, research of quadrotor unmanned aerial vehicles (QUAV) focuses on the design of the controller and optimization of the control algorithm. Dynamical analysis of the attitude system of QUAV has also been studied. In this paper, the stability of equilibrium points is further analyzed based on their distribution and bifurcation. Multi-initial phase-portraits demonstrate the multistability and the dynamical process from sinks to chaos of the system. The axis of its yaw angular velocity is proven to be a stable manifold, but a little perturbation to it leads to chaotic motion of the QUAV subject to an appropriate parameter configuration. Multi-initial phase-portraits, multi-initial bifurcation diagrams and basins of attraction altogether confirm that the discovered chaotic attractors are hidden and transient. The transient characteristic of these hidden attractors is investigated, revealing that they are natural sinks, which is confirmed by very long-time simulations.