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Collision-Avoidance Maneuver of Satellites Using Drag and Solar Radiation Pressure

JOURNAL OF GUIDANCE CONTROL AND DYNAMICS 2017年第5期40卷 1191-1205页

作者： Mishne, David Edlerman, Eviatar Technion Israel Inst Technol Fac Aerosp Engn IL-32000 Haifa Israel Technion Israel Inst Technol Distributed Space Syst Lab IL-32000 Haifa Israel

This paper discusses the feasibility of using drag and solar radiation pressure for a collision-avoidance maneuver. Usually, an alert about possible collision with another satellite or space debris is received a few days in advance, giving ample time to design and perform an avoidance maneuver. For a propulsionless satellite, drag and solar radiation pressure are the only natural forces that can be used for orbit maneuver. The maneuver is performed by orienting the satellite such that the combined effect of both forces will add up to maximize the change of the semimajor axis from the nonmaneuver case. This causes a change in the orbital period, and eventually, after enough revolutions, the satellite avoids the collision. The control algorithm requires the knowledge of the cross-section areas of the satellite from all directions as well as the drag and solar radiation properties. There must be a difference between the maximum cross-section area and the minimum one to control these natural forces. Numerical examples for a real satellite show that the method is feasible. The along-track deviation that is accumulated after no more than three days of maneuver is sufficient to reduce the collision probability to acceptable level.

关键词： Solar Radiation Earth Satellites algorithm performance Space Debris Orbital Period Radiation Properties Sun Synchronous Orbit Earth Reflectivity Drag Coefficient

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Search algorithm for Teams of Heterogeneous Agents with Coverage Guarantees

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JOURNAL OF AEROSPACE COMPUTING INFORMATION AND COMMUNICATION 2010年第1期7卷 1-31页

作者： Lum, Christopher W. Vagners, Juris Rysdyk, Rolf T. Univ Washington Dept Aeronaut & Astronaut Seattle WA 98195 USA Insitu Inc Design Anal & Flight Sci Bingen WA 98605 USA

Among common intelligence, reconnaissance, and surveillance tasks, searching for a target in a complex environment is a problem for which autonomous systems are well suited. This work considers the problem of searching for targets using a team of heterogeneous agents. The system maintains a grid-based world model which contains information about the probability that a target is located in a given cell of the map. Agents formulate control decisions for a fixed number of time steps using a modular algorithm that allows parameterizations of agent capabilities. This paper investigates a solution that guarantees total map coverage. The control law for each agent does not require explicit knowledge of other agents. This yields a system which is scalable to a large number of vehicles. The resulting search patterns guarantee an exhaustive search of the map in the sense that all cells will be searched sufficiently to ensure that the probability of a target going unnoticed is driven to zero. Modifications to this algorithm for explicit cooperation between agents is also investigated.

关键词： Search algorithm Autonomous Systems Raster Scanning Monte Carlo Simulation Probability Density Functions Model Predictive Control algorithm performance Path Planning Numerical Optimization Planar Kinematics

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Automated Splitting Gaussian Mixture Nonlinear Measurement Update

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JOURNAL OF GUIDANCE CONTROL AND DYNAMICS 2018年第3期41卷 725-734页

作者： Tuggle, Kirsten Zanetti, Renato Univ Texas Austin Dept Aerosp Engn & Engn Mech Austin TX 78712 USA

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Range-Based Relative Navigation for a Swarm of Centimeter-Scale Femto-Spacecraft

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JOURNAL OF GUIDANCE CONTROL AND DYNAMICS 2022年第9期45卷 1583-1597页

作者： Timmons, Thomas Beeley, James Bailet, Gilles McInnes, Colin R. Univ Glasgow Space & Explorat Technol Grp James Watt Sch Engn Glasgow G12 8QQ Lanark Scotland Univ Glasgow Space & Explorat Technol Grp James Watt Sch Engn Engn Sci Glasgow G12 8QQ Lanark Scotland

In-orbit relative navigation between a networked swarm of centimeter-scale femto-spacecraft would add considerable value to a range of space mission concepts and applications, such as for multipoint sensing and distributed sparse aperture interferometry. For a swarm of networked femto-spacecraft, relative position determination would be possible by inferring coarse range estimates from the received signal strength indication associated with the communication link between swarm members. This is particularly advantageous for highly resource-constrained devices. In this paper, algorithms for swarm relative positioning using interspacecraft range estimates are presented that can be applied to centralized, decentralized, and distributed network configurations. Relative navigation filters for initial relative orbit determination and state estimation are presented for femto-spacecraft swarm deployment and dispersal scenarios. The algorithms presented could also find use in terrestrial applications, in static and dynamic wireless sensor networks.

关键词： Spacecrafts Optical Sensor Orbit Determination Space Missions Extended Kalman Filter Singular Value Decomposition Satellite Formation algorithm performance Attitude Determination and Control System Additive White Gaussian Noise

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Optimal approach to SAR image segmentation and classification

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IEE PROCEEDINGS-RADAR SONAR AND NAVIGATION 2000年第3期147卷 134-142页

作者： Stewart, D Blacknell, D Blake, A Cook, R Oliver, C NA Software Ltd Liverpool Merseyside England DERA Malvern WR14 3PS Worcs England

Many algorithms have been proposed for the segmentation and classification of SAR imagery. Typically these are heuristic in basis, and more successful on some types of imagery than others. Methods based on global optimisation techniques can achieve the optimal solution of the posed problem;the algorithm is then characterised by an objective function and the chosen optimisation technique. The authors construct an appropriate objective function for SAR segmentation or classification, and show how to optimally quantify the relationship between the competing terms within it. This removes the previous need for the introduction of heuristics. Also described is an implementation based on simulated annealing, in which considerable attention has been paid to details, and examples are given of the resulting algorithm's performance upon real data.

关键词： RCS reconstruction SAR imagery image classification Radar theory SAR image classification Optimisation techniques real data heuristics segmentation algorithm objective function image segmentation optimal approach optimal solution algorithm performance radar cross-section simulated annealing global optimisation techniques Optical, image and video signal processing radar imaging synthetic aperture radar image reconstruction SAR image segmentation

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A multilevel evaluation method for heuristics with an application to the VRPTW

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INTERNATIONAL TRANSACTIONS IN OPERATIONAL RESEARCH 2020年第1期27卷 168-196页

作者： Corstjens, J. Depaire, B. Caris, A. Sorensen, K. UHasselt Res Grp Logist B-3590 Diepenbeek Belgium UHasselt Res Grp Business Informat B-3590 Diepenbeek Belgium Univ Antwerp Dept Engn Management Prinsstr B-2000 Antwerp Belgium

The field of combinatorial optimization has inspired the development of a large number of heuristic solution procedures. These methods are commonly assessed using a competitive evaluation methodology that may give an indication of which algorithm has a better performance. A next step in the experimental analysis is to uncover "why" one algorithm performs better. Which elements are responsible for good or bad performance? How does the performance of elements vary across the design space? What is the influence of the specific problem instance that is being solved? We focus on gaining a better understanding of heuristic algorithm performance and demonstrate that the application of a proper statistical methodology can provide researchers insight into how performance is affected by the different algorithm parameters and components. As an example, we apply a multilevel statistical analysis to a large neighborhood search algorithm for the vehicle routing problem with time windows.

关键词： algorithm performance statistical evaluation understanding vehicle routing problem with time windows large neighborhood search metaheuristics

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Real-Time Directed Rapidly Exploring Random Tree Path Planning for Air Collision Avoidance

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JOURNAL OF AEROSPACE INFORMATION SYSTEMS 2022年第5期19卷 330-343页

作者： Lee, Minkyu Noh, Geemoon Park, Jihoon Lee, Daewoo Pusan Natl Univ Dept Aerosp Engn Busan 46241 South Korea

In this paper, a path planning algorithm is proposed for dynamic obstacle avoidance by improving a rapidly exploring random tree (RRT) algorithm, a sampling-based path-planning algorithm. Although guaranteeing a globally optimal path is impossible when using RRT algorithm, it is advantageous because it can generate the path quickly. Considering this advantage of the RRT algorithm, the directed RRT (DRRT) algorithm was developed, which reduces the generation time and supplements optimality by improving node generation and tree expansion process. It is also added the path smoothing method for the flight. The anytime DRRT algorithm is based on the DRRT algorithm and repeats path generation within the time limit considering the direction of movement of the obstacle and selects the shortest path for the flight. Air collision avoidance between unmanned aerial vehicles (UAVs) considering the intruders as a dynamic obstacle was simulated using the Gazebo simulator. Based on the simulation, the performance of the proposed anytime DRRT algorithm was verified with varying the host UAV and intruder conditions, and its applicability to UAVs was affirmed.

关键词： Real Time Path Planning UAV Obstacle Avoidance Flight Testing Flight Simulation Rotary Wing MATLAB Flight Control Computer algorithm performance Attitude Control

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Moon-Tracking Modes for Star Trackers

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JOURNAL OF GUIDANCE CONTROL AND DYNAMICS 2010年第1期33卷 171-185页

作者： Enright, John Ryerson Univ Dept Aerosp Engn Toronto ON M5B 2K3 Canada

We examine the effectiveness and robustness of a moon-tracking backup mode for modern star trackers. This approach can be used to calculate a three-axis attitude solution from overexposed images of the moon. In examining this problem, we carefully consider the operational conditions under which this capability would be necessary and tailor our algorithmic approach appropriately. We describe a detailed simulation of the moon imaging process and outline the required image processing steps required to extract useful information from the moon images. The image processing extracts the moon outline and estimates the moon position and orientation using a nonlinear least-squares fit. Under most lighting conditions, our moon-vector estimates have an error of about 0.001 deg, and our sun-vector estimates have an error less than 0.25 deg. The capability of maintaining moderate accuracy attitude tracking in the presence of moon incursions is an important milestone toward a star-tracker-only attitude control system for microsatellites and nanosatellites.

关键词： Attitude Control System Moon Geostationary Satellites Image Processing Attitude Tracking Image Formation Earth algorithm performance Track algorithm Metal Oxide Semiconductors

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Fast Iterative algorithm for Solving Moser-Veselov Equation

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JOURNAL OF GUIDANCE CONTROL AND DYNAMICS 2015年第5期38卷 949-U187页

作者： Luo, Jinglin Yan, Guirong Xi An Jiao Tong Univ State Key Lab Strength & Vibrat Sch Aerosp Aeronaut & Astronaut Xian 710049 Peoples R China Xi An Jiao Tong Univ State Key Lab Strength & Vibrat Sch Aerosp Xian 710049 Peoples R China

The fast Moser?Veselov iterative algorithm (FMVIA) proposed in this study adopts the same methodology as the other two existing iterative algorithms, but the computation time for iterations is reduced by avoiding the trigonometric functions. This improves the speed of convergence by choosing different forms of the cayley transform and introducing a new parameter form by decomposing the right-hand term of the Moser?Veselov equation and building a new parameter, the inertia ratio. Numerical simulations are conducted to compare performances of each algorithm in finding solutions to the Moser?Veselov equation. A solution for a rigid body rotating around its three principal axes and accelerating under a conservative force has been sought as a practical example to compare the speed of calculation for the corresponding Moser?Veselov equation using different methods.

关键词： algorithm performance Numerical Simulation Explicit Methods UAV Banach Fixed Point Theorem Embedded Systems Riccati Equations Flight Control Robotics Robots

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Sequential attitude and attitude-rate estimation using integrated-rate parameters

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JOURNAL OF GUIDANCE CONTROL AND DYNAMICS 1999年第3期22卷 385-394页

作者： Oshman, Y Markley, FL Technion Israel Inst Technol Dept Aerosp Engn IL-32000 Haifa Israel NASA Goddard Space Flight Ctr Guidance Navigat & Control Ctr Greenbelt MD 20771 USA

A sequential nonlinear algorithm is presented for gyroless satellite attitude and attitude-rate estimation using vector observations. Based on a third-order, minimal-parameter method for solving the attitude matrix kinematic equation, the resulting estimator is rendered computationally efficient. Employing tracking theory concepts, the angular acceleration is modeled as an exponentially autocorrelated stochastic process, thereby avoiding the use of the typically uncertain spacecraft dynamic model. The estimator's performance is demonstrated via a numerical example, in which it is compared with the estimator implemented onboard the gyroless Solar, Anomalous, and Magnetospheric Particle Explorer spacecraft.

关键词： Satellites Attitude Control System Euler Angles Singular Value Decomposition Attitude Gyros Air to Air Missiles Euler Equations Spacecraft Attitude Power Spectral Density algorithm performance

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