Modeling and multi-domain coupling simulation analysis of a simplified model for aircraft nose landing gear retraction and extension mechanism

Abstract

The aircraft nose landing gear retraction mechanism is a typical mechatronic system, and its dynamic performance is critical to retraction reliability, structural safety, and the operational reliability of the entire aircraft. With the increasing demand for digital design in aerospace equipment, traditional analysis methods reliant on prototype testing are no longer sufficient to meet the requirements for rapid design and performance verification of nose landing gear retraction mechanisms in terms of parameter iteration efficiency. This paper takes a simplified double-linkage nose landing gear retraction mechanism driven by a single hydraulic cylinder as its subject of study. Based on MATLAB/Simulink, a coupled digital model spanning the mechanical, hydraulic, and control domains is established, and a modular modelling and coupled simulation workflow is proposed. Simulation results indicate that the coupled model captures the characteristics of displacement, chamber pressure, and hinge loads; after incorporating valve dynamics and hydraulic non-linearities, the controller requires feedforward and limiting measures to suppress oscillations. This paper also discusses the calibration of modelling parameters, the handling of numerical stability, and the prospects for extending the approach to digital twin applications. This work provides an executable modelling framework and simulation verification process for the digital design and reliability assessment of front landing gear retraction mechanisms.