Finite-time adaptive sliding mode tracking control for a quadrotor unmanned aerial vehicle with model uncertainties and external disturbances

A finite-time adaptive sliding mode controller is designed to improve the trajectory tracking capability of a quadrotor unmanned aerial vehicle (UAV) in the presence of model uncertainties and unmodeled external disturbances. By applying adaptive nonsingular fast terminal sliding mode control (ANFTSMC) to the quadrotor UAV system, rapid response, finite-time convergence, and high-precision steady-state control are achieved under uncertainties and external disturbances, while also avoiding singularities and reducing the effect of chattering. Furthermore, the adaptive strategy is designed to estimate the upper bounds of model uncertainties and external disturbances without requiring prior bounded information. The finite-time convergence capability of the system is rigorously analyzed using the Lyapunov stability framework. Extensive simulation studies and experimental validations collectively demonstrate the efficacy of the designed control scheme. Notably, stable flight in the presence of wind disturbances and control of the contact force in experiments with wind turbine blades underscore the applicability of the strategy for achieving reliable quadrotor UAV operations in complex environments.