Flight Control of a Multirotor Aerial Vehicle using a Nonsingular Terminal Sliding Mode Control

Arioberto Luciano da Silva Júnior¹; Davi Antônio dos Santos¹

¹ Instituto Tecnológico de Aeronáutica

doi:10.20906/CPS/CILAMCE2017-0490

Resumo

A multirotor aerial vehicle is a highly nonlinear coupled system with uncertain parameters and subject to force and torque disturbances. The purpose of the present work is to design a flight control system for an autonomous quadrotor vehicle using a recent formulation of the sliding mode control (SMC) strategy, namely the nonsingular fast terminal sliding model control (NFTSMC), to track a desired trajectory. A hierarchical control structure is adopted by considering a time-scale separation between the translational and rotation dynamics. In this structure, the position control is realized by an outer slower loop, while the attitude control is carried out by an inner faster loop. For each loop, we first formulate a six-state dynamics model for the respective tracking error and then apply the NFTSMC strategy to steer it toward the origin. In particular, the tracking error of the rotational motion, the modified Rodrigues parameters are considered for representing the attitude error. Considering that the torque and force disturbances are bounded inside known sets, the adopted strategy leads to attitude and position control laws that are capable to globally track a desired trajectory with finite-time convergence and singularity avoidance. The proposed method is evaluated on extensive numerical simulations, showing its effectiveness as well as some of its properties.

Palavras-chave: multirotor aerial vehicle; flight control; terminal sliding mode control