A Comprehensive Review of Flight Control Strategies for Quadrotor UAVS and Performance Analysis Using a Backstepping Control Method

This paper presents a structured review of flight control strategies for quadrotor unmanned aerial vehicles and identifies key research gaps affecting reliable operation under uncertain conditions. The study applies a systematic classification and analytical comparison of control approaches, including linear control, nonlinear Lyapunov-based methods, sliding mode control, adaptive and observer-based control, predictive control, and learning-enhanced strategies. Based on this review, a backstepping-based trajectory tracking controller is developed as a representative case study. The quadrotor dynamic model is established using Newton–Euler equations and organized into a cascade control structure with an outer-loop position controller and an inner-loop attitude controller. Stability of the closed-loop system is ensured using Lyapunov theory. Simulation results show that the proposed controller achieves accurate trajectory tracking with position and attitude errors converging to zero within approximately 5–8 seconds, while maintaining stable and feasible control inputs. The results confirm that backstepping provides strong theoretical stability and good tracking performance under nominal conditions; however, its robustness remains limited when disturbances and uncertainties are present. Therefore, integrating disturbance observers and adaptive mechanisms into backstepping control is identified as a promising direction for improving robustness and practical applicability in quadrotor control systems.