Path-Following Guidance for Unmanned Aerial Vehicle with Bounded Lateral Acceleration

TL;DR

This paper introduces a nonlinear guidance method for UAVs that guarantees bounded control inputs and exponential path convergence, effectively handling actuator constraints in 3D path-following tasks.

Contribution

It develops a nested saturation-based guidance framework that explicitly incorporates bounded lateral acceleration for improved UAV path tracking.

Findings

Guarantees bounded control inputs and exponential convergence.

Achieves superior tracking performance and robustness.

Demonstrates effectiveness through simulations on various paths.

Abstract

This paper addresses the three-dimensional path-following guidance problem for unmanned aerial vehicles under explicit actuator constraints. Unlike conventional approaches that assume unbounded control inputs or handle saturation heuristically, the proposed method incorporates bounded lateral acceleration directly into the guidance design. A nonlinear guidance framework is developed employing a nested saturation-based control technique. The proposed guidance strategy guarantees bounded control inputs while ensuring exponential convergence of cross-track errors to zero. The formulation is applicable to general smooth paths and is systematically extended from planar to three-dimensional scenarios using a path-tangent coordinate framework. Rigorous stability analysis based on Lyapunov theory establishes convergence and feasibility properties of the closed-loop system. Numerical simulations on representative paths, including straight-line, circular, and sinusoidal paths, demonstrate that the proposed method achieves superior tracking performance, reduced control effort, and robustness against disturbances compared to existing guidance laws. The simplicity of the design and its compatibility with practical actuator limits make it suitable for real-world UAV applications.