aircraft model
CNN-Based Camera Pose Estimation and Localisation of Scan Images for Aircraft Visual Inspection
Oh, Xueyan, Loh, Leonard, Foong, Shaohui, Koh, Zhong Bao Andy, Ng, Kow Leong, Tan, Poh Kang, Toh, Pei Lin Pearlin, Tan, U-Xuan
Abstract--General Visual Inspection is a manual inspection process regularly used to detect and localise obvious damage on the exterior of commercial aircraft. There has been increasing demand to perform this process at the boarding gate to minimise the downtime of the aircraft and automating this process is desired to reduce the reliance on human labour . Automating this typically requires estimating a camera's pose with respect to the aircraft for initialisation but most existing localisation methods require infrastructure, which is very challenging in uncontrolled outdoor environments and within the limited turnover time (approximately 2 hours) on an airport tarmac. Additionally, many airlines and airports do not allow contact with the aircraft's surface or using UA Vs for inspection between flights, and restrict access to commercial aircraft. Hence, this paper proposes an on-site method that is infrastructure-free and easy to deploy for estimating a pan-tilt-zoom camera's pose and localising scan images. This method initialises using the same pan-tilt-zoom camera used for the inspection task by utilising a Deep Convolutional Neural Network fine-tuned on only synthetic images to predict its own pose. We apply domain randomisation to generate the dataset for fine-tuning the network and modify its loss function by leveraging aircraft geometry to improve accuracy. We also propose a workflow for initialisation, scan path planning, and precise localisation of images captured from a pan-tilt-zoom camera. We evaluate and demonstrate our approach through experiments with real aircraft, achieving root-mean-square camera pose estimation errors of less than 0.24 m and 2 for all real scenes. General Visual Inspection (GVI) is a widely used technique as part of regular inspections of aircraft such as during pre-flight inspections on an airport tarmac or during maintenance usually performed in a hanger. This process involves visual examinations of the aircraft's exterior for noticeable damage or irregularities and provides a means for early detection of typical air-frame defects [2].
ROSplane 2.0: A Fixed-Wing Autopilot for Research
Reid, Ian, Ritchie, Joseph, Moore, Jacob, Sutherland, Brandon, Snow, Gabe, Tokumaru, Phillip, McLain, Tim
Unmanned aerial vehicle (UAV) research requires the integration of cutting-edge technology into existing autopilot frameworks. This process can be arduous, requiring extensive resources, time, and detailed knowledge of the existing system. ROSplane is a lean, open-source fixed-wing autonomy stack built by researchers for researchers. It is designed to accelerate research by providing clearly defined interfaces with an easily modifiable framework. Powered by ROS 2, ROSplane allows for rapid integration of low or high-level control, path planning, or estimation algorithms. A focus on lean, easily understood code and extensive documentation lowers the barrier to entry for researchers. Recent developments to ROSplane improve its capacity to accelerate UAV research, including the transition from ROS 1 to ROS 2, enhanced estimation and control algorithms, increased modularity, and an improved aerodynamic modeling pipeline. This aerodynamic modeling pipeline significantly reduces the effort of transitioning from simulation to real-world testing without requiring expensive system identification or computational fluid dynamics tools. ROSplane's architecture reduces the effort required to integrate new research tools and methods, expediting hardware experimentation.
A Data-Driven Autopilot for Fixed-Wing Aircraft Based on Model Predictive Control
Richards, Riley J., Paredes, Juan A., Bernstein, Dennis S.
In particular, PCAC is implemented as a cold-start A fundamental necessity for autonomous atmospheric indirect adaptive controller, where the plant model order is flight vehicles is a reliable autopilot for controlling the specified as a hyperparameter, but otherwise no plant model attitude and flight path. For a fixed-wing vehicle, stability and is assumed to be available. The identified model updated control derivatives are typically determined through windtunnel by RLS is linear, and thus it is suitable for modeling the testing or computational modeling over a range of aircraft dynamics near trim. In practice, an autopilot designed Mach number, angle of attack, and sideslip angle. This to operate over a wide range of flight conditions depends modeling data is then used to develop an autopilot based on on gain scheduling of multiple linear controllers. The goal gain scheduling, feedback linearization, or dynamic inversion of this study is to investigate, via numerical experiments, [1], [2]. In practice, however, the aerodynamics of an aircraft the viability and potential performance of PCAC under may be too expensive to model with high accuracy or may conditions of high uncertainty, in effect, no prior modeling change due to atmospheric conditions, such as icing, as well information, without the need for gain scheduling.
An Integrated Imitation and Reinforcement Learning Methodology for Robust Agile Aircraft Control with Limited Pilot Demonstration Data
Sever, Gulay Goktas, Demir, Umut, Satir, Abdullah Sadik, Sahin, Mustafa Cagatay, Ure, Nazim Kemal
In this paper, we present a methodology for constructing data-driven maneuver generation models for agile aircraft that can generalize across a wide range of trim conditions and aircraft model parameters. Maneuver generation models play a crucial role in the testing and evaluation of aircraft prototypes, providing insights into the maneuverability and agility of the aircraft. However, constructing the models typically requires extensive amounts of real pilot data, which can be time-consuming and costly to obtain. Moreover, models built with limited data often struggle to generalize beyond the specific flight conditions covered in the original dataset. To address these challenges, we propose a hybrid architecture that leverages a simulation model, referred to as the source model. This open-source agile aircraft simulator shares similar dynamics with the target aircraft and allows us to generate unlimited data for building a proxy maneuver generation model. We then fine-tune this model to the target aircraft using a limited amount of real pilot data. Our approach combines techniques from imitation learning, transfer learning, and reinforcement learning to achieve this objective. To validate our methodology, we utilize real agile pilot data provided by Turkish Aerospace Industries (TAI). By employing the F-16 as the source model, we demonstrate that it is possible to construct a maneuver generation model that generalizes across various trim conditions and aircraft parameters without requiring any additional real pilot data. Our results showcase the effectiveness of our approach in developing robust and adaptable models for agile aircraft.
Conformal Predictions Enhanced Expert-guided Meshing with Graph Neural Networks
Nobari, Amin Heyrani, Rey, Justin, Kodali, Suhas, Jones, Matthew, Ahmed, Faez
Computational Fluid Dynamics (CFD) is widely used in different engineering fields, but accurate simulations are dependent upon proper meshing of the simulation domain. While highly refined meshes may ensure precision, they come with high computational costs. Similarly, adaptive remeshing techniques require multiple simulations and come at a great computational cost. This means that the meshing process is reliant upon expert knowledge and years of experience. Automating mesh generation can save significant time and effort and lead to a faster and more efficient design process. This paper presents a machine learning-based scheme that utilizes Graph Neural Networks (GNN) and expert guidance to automatically generate CFD meshes for aircraft models. In this work, we introduce a new 3D segmentation algorithm that outperforms two state-of-the-art models, PointNet++ and PointMLP, for surface classification. We also present a novel approach to project predictions from 3D mesh segmentation models to CAD surfaces using the conformal predictions method, which provides marginal statistical guarantees and robust uncertainty quantification and handling. We demonstrate that the addition of conformal predictions effectively enables the model to avoid under-refinement, hence failure, in CFD meshing even for weak and less accurate models. Finally, we demonstrate the efficacy of our approach through a real-world case study that demonstrates that our automatically generated mesh is comparable in quality to expert-generated meshes and enables the solver to converge and produce accurate results. Furthermore, we compare our approach to the alternative of adaptive remeshing in the same case study and find that our method is 5 times faster in the overall process of simulation. The code and data for this project are made publicly available at https://github.com/ahnobari/AutoSurf.