V3I6P59

Adaptive Gain Sliding Mode Control for Quadrotor UAV Trajectory Tracking Under Full Nonlinear Dynamics 

Khuat Quang Tien^1*

Abstract

This paper presents an Improved Adaptive Sliding Mode Control (IASMC) synthesis method for quadrotor UAV systems based on the full nonlinear dynamics model derived from the Newton–Euler formulation. A quadrotor is characterized by strong nonlinearities, six degrees of freedom, and tight coupling among axes, which makes trajectory–tracking control challenging under disturbances and parameter uncertainties. The proposed method extends the classical sliding mode controller by integrating a channel–wise adaptive law, allowing dynamic adjustment of the control gain according to the error magnitude, thereby reducing chattering while maintaining Lyapunov stability. The complete quadrotor model is analyzed, sliding surfaces and equivalent control laws are clearly constructed, followed by integrating an adaptive component with a saturation function to enhance smoothness and tracking performance. The analysis results demonstrate that the IASMC guarantees global stability, improves accuracy and disturbance rejection capability, and is suitable for practical implementation on UAVs with actuator power limits and motor delays.

Keywords:

Quadrotor UAV; Sliding Mode Control; Adaptive Control; Newton–Euler; Nonlinear System; Lyapunov; Chattering.