Flight Dynamics and Hybrid Adaptive Control of Damaged Aircraft

TLDR

The study investigates flight dynamics and adaptive control strategies to recover stability and control in a damaged generic transport aircraft. The authors model damage‑induced aerodynamic changes, develop a flight dynamics model with iterative trim, and implement a neural‑network hybrid direct‑indirect adaptive controller that estimates plant dynamics online using Lyapunov‑based indirect laws and recursive least‑squares. Simulations demonstrate that the hybrid adaptive controller markedly improves tracking performance compared to a direct adaptive controller alone.

Abstract

This paper presents a recent study to investigate flight dynamics and adaptive control methods for stability and control recovery of a damaged generic transport aircraft. Aerodynamic modeling of damage effects is performed using an aerodynamic code to assess changes in the stability and control derivatives of the damaged aircraft. Flight dynamics for a general aircraft are developed to account for changes in aerodynamics, mass properties, and the center of gravity that can compromise the stability of the damaged aircraft An iterative trim analysis is developed to compute incremental trim states. A neural network hybrid direct-indirect adaptive flight control is developed for the stability augmentation control of the damaged aircraft. The proposed method performs an online estimation of damaged plant dynamics to improve the command tracking performance in conjunction with a direct adaptive controller. The plant estimation is based on two approaches: 1) an indirect adaptive law derived from the Lyapunov stability theory to ensure that the tracking error is bounded, and 2) a recursive least-squares method that minimizes the modeling error. Simulations show that the hybrid adaptive controller can provide a significant improvement in the tracking performance over a direct adaptive controller working alone.