检索结果-内蒙古大学图书馆

Autonomous Vision-Based Algorithm for Interplanetary Navigation

JOURNAL OF GUIDANCE CONTROL AND DYNAMICS 2024年第9期47卷 1792-1807页

作者： Andreis, Eleonora Panicucci, Paolo Topputo, Francesco Polytech Univ Milan Dept Aerosp Sci & Technol Via La Masa 34 I-20156 Milan Italy Deutsch Zentrum Luft & Raumfahrt DLR Bremen Germany

The surge of deep-space probes makes it unsustainable to navigate them with standard radiometric tracking. Autonomous interplanetary satellites represent a solution to this problem. In this work, a vision-based navigation algorithm is built by combining an orbit determination method with an image processing pipeline suitable for interplanetary transfers of autonomous platforms. To increase the computational efficiency of the algorithm, an extended Kalman filter is selected as state estimator, fed by the positions of the planets extracted from deep-space images. An enhancement of the estimation accuracy is performed by applying an optimal strategy to select the best pair of planets to track. Moreover, a novel analytical measurement model for deep-space navigation is developed providing a first-order approximation of the light-aberration and light-time effects. Algorithm performance is tested on a high-fidelity, Earth-Mars interplanetary transfer, showing the algorithm applicability for deep-space navigation.

关键词： Interplanetary Trajectories Space Commercialization Image Processing Orbit Determination algorithms and data structures Space Probe Autonomous Navigation System Extended Kalman Filter Spacecraft Navigation Onboard Navigation System

来源：评论

学校读者我要写书评

暂无评论

Variational Quantum algorithms for Computational Fluid Dynamics

引用

AIAA JOURNAL 2023年第5期61卷 1885-1894页

作者： Jaksch, Dieter Givi, Peyman Daley, Andrew J. Rung, Thomas Univ Hamburg Inst Laser Phys Phys Luruper Chaussee 149Gebaude 69 D-22761 Hamburg Germany Univ Pittsburgh Mech Engn & Petr Engn Pittsburgh PA 15260 USA Univ Strathclyde Dept Phys Glasgow G4 0NG Scotland Univ Strathclyde SUPA Glasgow G4 0NG Scotland Hamburg Univ Technol Inst Fluid Dynam & Ship Theory Schwarzenberg Campus 4 D-21073 Hamburg Germany Univ Oxford Clarendon Lab Parks Rd Oxford OX1 3PU England

Quantum computing uses the physical principles of very small systems to develop computing platforms which can solve problems that are intractable on conventional supercomputers. There are challenges not only in building the required hardware but also in identifying the most promising application areas and developing the corresponding quantum algorithms. The availability of intermediate-scale noisy quantum computers is now propelling the developments of novel algorithms, with applications across a variety of domains, including in aeroscience. Variational quantum algorithms are particularly promising because they are comparatively noise tolerant and aim to achieve a quantum advantage with only a few hundred qubits. Furthermore, they are applicable to a wide range of optimization problems arising throughout the natural sciences and industry. To demonstrate the possibilities for the aeroscience community, we give a perspective on how variational quantum algorithms can be used in computational fluid dynamics. We discuss how classical problems are translated into quantum algorithms and their logarithmic scaling with problem size. For an explicit example, we apply this method to Burgers's equation in one spatial dimension. We argue that a quantum advantage over classical computing methods could be achieved by the end of this decade if quantum hardware progresses as currently envisaged and emphasize the importance of joining up development of quantum algorithms with application-specific expertise to achieve a real-world impact.

关键词： Computational Fluid Dynamics High Performance Computing Supercomputers Reynolds Averaged Navier Stokes Fluid Flow Properties Quantum Computing algorithms and data structures

来源：评论

学校读者我要写书评

暂无评论

Gradient-Based Optimization Method for Experimental Modal Parameter Estimation with Finite Element Model

引用

AIAA JOURNAL 2024年第9期62卷 3544-3558页

作者： Xu, Zhaoyi Zheng, Gangtie Tsinghua Univ Sch Aerosp Engn Beijing 100084 Peoples R China

This paper presents a novel gradient-based optimization algorithm for improving the accuracy of experimentally estimated modal parameters with the assistance of finite element models. Initially, we recast the discrete vibration response equation into a matrix form and formulate the parameter estimation problem in modal analysis as an optimization problem. Then the problem is solved with a gradient-based iterative algorithm, which explicitly exhibits the closed form of gradients used in optimization. Initial values for this iteration are parameters derived from finite element models, since every important engineering structure should be analyzed with a finite element model before it is constructed. Subsequently, the performance of this algorithm is validated by both pure numerical experiments, which simulate the physical world, and experiments using real measurement data gathered by sensors in the real physical world. The algorithm's performance is further enhanced by incorporating gradient clipping and an adaptive iteration threshold. As a comparison, a discussion on classical least-squares time-domain method for the problem is provided. For practical applications, the Shi-Tomasi corner detection and Lucas-Kanade optical flow methods are deployed to detect corner points from videos taken during the vibration of a structure and track the motion of these points in the videos.

关键词： Optimization Algorithm Finite Element Modeling Acceleration Sensors Operational Modal Analysis algorithms and data structures Corner Detection Mechanical and Structural Vibrations Beam (structures) Applied Mathematics Signal Processing

来源：评论

学校读者我要写书评

暂无评论

Shadow-Robust Silhouette Reconstruction for Small-Body Applications

引用

JOURNAL OF SPACECRAFT AND ROCKETS 2023年第3期60卷 812-828页

作者： Panicucci, Paolo Lebreton, Jeremy Brochard, Roland Zenou, Emmanuel Delpech, Michel ISAE SUPAERO Complex Syst Engn Dept 10 Ave Edouard Belin F-31400 Toulouse France Ctr Natl Etud Spatiales 18 Ave Edouard Belin F-31400 Toulouse France Airbus Def & Space 31 Rue Cosmonautes F-31400 Toulouse France Politecn Milan Dept Aerosp Sci & Technol Milan Italy Complex Syst Engn Dept 10 Ave Edouard Belin Toulouse France Ctr Natl Etud Spatiales Future Mission Engn Dept 18 Ave Edouard Belin F-31400 Toulouse France

Small bodies' exploration highlighted the need to develop new algorithms for deep space probes navigation. The estimation of the small-body shape is a crucial step for relative navigation, mission planning, and gravity investigation. This paper develops a shape from silhouette algorithm that takes as input a series of images to construct a polyhedral shape for small bodies of the solar system. First, the silhouette associated with the visible part of the body is extracted and modified to account for shadowing effects. Second, the shape is computed by intersecting the viewing cones, i.e., the cone whose apex is the camera center and whose vertices are the silhouette points. The algorithm output is a polyhedral shape whose reconstruction is robust to shadowing. The algorithm is validated by reconstructing the shape of Itokawa and Bennu from synthetic images simulated with Airbus Defence & Space's rendering engine SurRender (TM). Moreover, the algorithm is tested on real images from Hayabusa's approach. Results prove the capability to provide an efficient shape reconstruction for small-body applications.

关键词： Planetary Science and Exploration Space Probe Asteroids Computing and Informatics algorithms and data structures Vision for Space Exploration Vision Based Navigation Space Exploration and Technology Self-Shadowing Effects Optical Sensor

来源：评论

学校读者我要写书评

暂无评论

Simulated Scramjet Shock Train Control Using an All-Coefficient Adaptive Control Approach

引用

JOURNAL OF PROPULSION AND POWER 2023年第4期39卷 492-500页

作者： Rockwell, Robert Goyne, Chris Di, Long Lin, Zongli Bakos, Robert Donbar, Jeffrey Univ Virginia Mech & Aerosp Engn Charlottesville VA 22904 USA Univ Virginia Elect & Comp Engn Charlottesville VA 22904 USA Innoveering LLC Ronkonkoma NY 11779 USA US Air Force Res Lab Dayton OH 45433 USA

This paper explores the use of dual-mode scramjet shock train control taking an adaptive control approach known as characteristic model-based all-coefficient adaptive control. In this study a simple, semiempirical model of a dual-mode scramjet is developed. This model is suited to computationally efficient control simulation for the assessment of different control approaches. All-coefficient adaptive control is predicted to be as capable of controlling the shock train location, and rejecting disturbances, as a traditional proportional-integral-derivative controller. However, prior knowledge of the scramjet plant is not required for the all-coefficient adaptive control, and it is predicted that this controller is able to better perform when changes in the plant take place. When characteristics of the plant deviate from their nominal values, the adaptive controller can adjust in real time and maintain a stable system response. This is the first time the performance of all-coefficient adaptive control has been examined in the open literature for a dual-mode scramjet. It is also the first time all-coefficient adaptive control of a dual-mode scramjet has been compared to proportional-integral-derivative control. The simple, empirically based plant model of the dual-mode scramjet is also new, and it is well suited to real-time and hardware-in-the-loop control simulations.

关键词： Scramjet Proportional Integral Derivative Control Combustors Aircraft Fuel System Fuel Injection algorithms and data structures Pressure Sensors Shock Train Adaptive Control Hypersonic Aircraft

来源：评论

学校读者我要写书评

暂无评论

Distributed Intelligent Adaptive Controller for Disturbance Rejection in Multiagent Systems

引用

JOURNAL OF AEROSPACE INFORMATION SYSTEMS 2023年第5期20卷 276-288页

作者： Festa-Odera, Diana Moncayo, Hever Aoun, Christoph Gutierrez, Tatiana Embry Riddle Aeronaut Univ Daytona Beach FL 32114 USA Adv Dynam & Control Lab Aerosp Engn Dept 1 Aerosp Blvd Daytona Beach FL 32114 USA

A cooperative task consisting of multiple agents has the advantages of reducing cost, enhancing configurability, and increasing robustness in a large set of mission applications. A distributed strategy, applied using intelligence and adaptability characteristics, can provide the extended potential to achieve high levels of mission protection, especially under disturbances that might lead to operation degradation. This paper describes the design and development of a novel bioinspired distributed adaptive control architecture designed to increase the resilience of multiagent systems. The architecture is formulated using nonlinear bounded functions that characterize the immune system responses of living organisms. Numerical simulations are performed to evaluate the capabilities of this architecture to solve a consensus problem under bounded disturbances. Stability analysis is presented using the Lyapunov direct method to estimate the radius of convergence of the global tracking error under a time-varying disturbance. The proposed distributed controller successfully ensures that consensus is achieved among all agents while simultaneously mitigating the effect of disturbances.

关键词： Multi Agent System Model Reference Adaptive Control Computational Fluid Dynamics Artificial Immune System algorithms and data structures Reinforcement Learning Algebraic Riccati Equation Quadcopter Feedback Linearization Cyber Physical System

来源：评论

学校读者我要写书评

暂无评论

Computing the Center of Uncertain Points on Tree Networks

引用

ALGORITHMICA 2017年第1期78卷 232-254页

作者： Wang, Haitao Zhang, Jingru Utah State Univ Dept Comp Sci Logan UT 84322 USA

Uncertain data has been very common in many applications. In this paper, we consider the one-center problem for uncertain data on tree networks. In this problem, we are given a tree T and n (weighted) uncertain points each of which has m possible locations on T associated with probabilities. The goal is to find a point x* on T such that the maximum (weighted) expected distance from x* to all uncertain points is minimized. To the best of our knowledge, this problem has not been studied before. We propose a refined prune-and-search technique that solves the problem in linear time.

关键词： Facility location One-center Uncertain data Tree network algorithms and data structures

来源：评论

学校读者我要写书评

暂无评论

General Burnback Analysis for Anisotropic and Heterogeneous Solid Propellants

引用

JOURNAL OF PROPULSION AND POWER 2024年第5期40卷 769-780页

作者： Tizon, Juan M. Benavides, Efren M. Univ Politecn Madrid UPM Fluid Dynam & Aerosp Prop Dept Madrid 28040 Spain

For several decades, researchers have successfully computed surface burnback to perform complex analyses and simulations related to the combustion of solid propellants. Many of these methods are heuristic or empirical, lacking a rigorous foundation, whereas others introduce numerical issues not related with the involved physics. This paper establishes a common theoretical and numerical core that bases the general study of burnback problems even in the case of designing nonconventional propellants. It starts with Piobert's statement as a first principle, derives that the eikonal formulation holds for propellants with heterogeneous and anisotropic recession rates, and gives a general mathematical structure for both situations. Then, several configurations found by rocket designers are numerically solved in order to show the efficiency and the accuracy of the theory. The main conclusion is that a direct numerical integration of the eikonal equation using a time marching method is enough in terms of computational efficiency and accuracy to track the combustion surface of any anisotropic and heterogeneous solid propellant.

关键词： Heterogeneous Solid Propellant Numerical Integration Rockets Solid Propellant Rocket Engines Combustion Process Solid Propellant Rocket Monopropellants algorithms and data structures Aerodynamics Bipropellants

来源：评论

学校读者我要写书评

暂无评论

Transient Three-Dimensional Measurement of Ice Crystal Accretion Using a Plenoptic Camera

引用

AIAA JOURNAL 2024年第11期62卷 4461-4472页

作者： Eberhart, Martin Loehle, Stefan Grigat, Felix Connolly, Jonathan McGilvray, Matthew Gillespie, David R. H. Univ Stuttgart D-70569 Stuttgart Germany Univ Oxford Oxford Thermofluids Inst Dept Engn Sci Oxford OX2 0ES England

Monitoring the three-dimensional formation of ice layers on airfoils during icing wind tunnel experiments is extremely challenging. For the first time, this paper demonstrates the use of a single plenoptic camera to perform transient, nonintrusive in situ measurements of ice crystal accretion. Experiments have been conducted in the Altitude Icing Wind Tunnel at the National Research Council of Canada under different icing conditions to assess the potential of the new technique. Using the camera in a close-up configuration, the results show the evolution of the three-dimensional shape of the accreted ice in high spatial and temporal resolution and in absolute metric units. The computed surface meshes allow for a detailed analysis in terms of ice shape, surface area, and ice volume. Posttest shapes are compared to measurements taken using a commercial laser scanner. Although not rated for ice surfaces, this device is used as a reference to compare the detailed surface structure after registering the data sets. The results of the two methods are in good agreement and show a mean relative deviation of the plenoptic camera of about 0.15 mm.

关键词： Icing Wind Tunnel Space Exploration and Technology Aviation Weather Hazards Aerodynamic Performance Optical Properties Statistical Analysis Computer-Aided Manufacturing algorithms and data structures Computer Vision Image Sensor

来源：评论

学校读者我要写书评

暂无评论

Storm Classification and Dynamic Targeting for a Smart Ice Cloud Sensing Satellite

引用

JOURNAL OF AEROSPACE INFORMATION SYSTEMS 2024年第12期21卷 958-971页

作者： Swope, Jason Chien, Steve Bosch-Lluis, Xavier Dunkel, Emily Yue, Qing Ogut, Mehmet Ramos, Isaac Kangaslahti, Pekka Deal, William Cooke, Caitlyn CALTECH Jet Prop Lab 4800 Oak Grove Dr Pasadena CA 91109 USA Northrop Grumman Linthicum MD USA

Smart Ice Cloud Sensing (SMICES) is a small-sat concept in which a radar intelligently targets ice storms based on information collected by a look-ahead radiometer. Often, space observations are performed by continuously collecting data from an instrument aimed at nadir (e.g., directly below the space platform). However, if the platform has the ability to assess science utility of features that will be overflown, an intelligent measurement scheme can improve science return. In the case of SMICES, power constraints and the rarity of storms mean that with blind nadir targeting SMICES would collect a limited amount of ice-storm radar data. The work proposed acquires measurements to maximize acquired high-interest storms while concurrently collecting a background sampling of all features. This is accomplished through two steps: storm classification and dynamic targeting. For classification, we describe a multistep use of machine learning and digital twin of Earth's atmosphere to create a classifier. We discuss an autonomous data labeling pipeline used to train five different models to identify storms in tropical and nontropical regions and assess the results and impact of expected noise. For dynamic targeting, six algorithms, ranging from "blind" to more selective, are described and evaluated on their improvement over "blind" targeting.

关键词： Cloud Physics Satellites Radar data Naive Bayes Classifier Digital Engineering Planetary Atmospheres Convection Convolutional Neural Network algorithms and data structures Planets

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：