Modelling and implementation of a real-time flexible aircraft simulation environment with animation of flight path, attitude and airframe deformation

This thesis presents the development and implementation of a real-time animation tool designed to visualise the deformation of flexible aircraft. The primary objectives are to create a robust framework that accurately represents the deformation of the wing, the horizontal tail, and the vertical tail and to evaluate the performance of the tool under various simulated conditions. The demonstrator aircraft used for this thesis is the UP-Wing aircraft model. This aircraft is the DLR F-25 research aircraft with modified wing parameters. The DLR F-25 is similar to the Airbus A321 neo but with a high aspect ratio. The methodology used to develop this animation tool consists of three main steps. First, the aeroelastic flight dynamics model was calculated and simulated using MATLAB/Simulink. Then, the 3-D model was animated in X-Plane. Finally, a plugin was implemented to facilitate the communication between Simulink and X-Plane. The aeroelastic flight dynamics model included the calculation of rigid body stability derivatives using AVL, the extraction of eigenvalues and eigenvectors from NASTRAN, and the simulation of the flexible flight dynamics model in Simulink. Furthermore, the aeroelastic flight dynamics model included two aerodynamic approaches: quasi-steady and unsteady. However, the animation tool was only applied to the quasi-steady aerodynamic simulations due to the high processing time of the unsteady model, which made real-time animation impractical. In addition, for the animation process in X-Plane, an extensively modified 3-D model of an Airbus A320 was used. The modifications were performed using Blender and it included rigging and animating of the 3-D model. Subsequently, the aircraft was painted using ArmorPaint software. In a further step, a custom plugin was implemented in C++ to disable the X-Plane physics engine and facilitate data transfer from Simulink. Then, the performance of the animation tool was investigated. In this regard, time domain simulations were conducted for both longitudinal and lateral motions of the aircraft, using different input scenarios to analyse the dynamic response and structural behaviour. The investigation revealed
that the developed animation tool successfully displayed the real-time animation of the aircraft’s structural response. The performance of the tool was verified by comparing the X-Plane animation results with the MATLAB/Simulink plots, ensuring the reliability of the data transfer and animation accuracy. This real-time animation tool for flexible aircraft deformations has significant applications in the aircraft design phase, educational purposes, and virtual flight testing, improving both costreduction and safety. In addition, the tool can be applied to any aircraft model.