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Optimal earth-moon trajectories using combined chemical-electric propulsion

JOURNAL OF GUIDANCE CONTROL AND DYNAMICS 1997年第2期20卷 253-258页

作者： Kluever, CA University of Missouri–Columbia/Kansas City Kansas City Missouri 64110-2499

Minimum-fuel, three-dimensional Earth-moon trajectories are obtained for spacecraft using both chemical and electric propulsion stages. The problem involves maximizing the final spacecraft mass delivered to a circular, polar midlunar orbit, The mission definition involves a chemical-stage boost from low-Earth orbit into a coasting ballistic trajectory followed by a lunar capture trajectory performed by the electric propulsion stage. For this analysis, the ballistic orbit transfer and the powered orbit transfer to a circular orbit within the lunar sphere of influence are modeled by the dynamics of the classical restricted three-body problem, and two body-centered coordinate frames are utilized, The subsequent descending three-dimensional spiral trajectory to circular polar midlunar orbit is computed via Edelbaum's analytic equations in order to eliminate the need to numerically simulate the numerous near-circular lunar orbits, Two classes of current-term electric propulsion thrusters are utilized (arcjet and plasma thrusters) along with current-term launch vehicle configurations, Numerical results are presented, and the optimal chemical-electric propulsion transfers exhibit a substantial reduction in trip time compared to Earth-moon transfers using electric propulsion alone.

关键词： Electric Propulsion Earth Moon Solar Electric Propulsion Launch Vehicles Arcjet Thruster Exhaust Velocity sequential quadratic programming Trajectory Optimization Nonlinear programming

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Trajectory Optimization and Cost Estimation of Laser Propulsion Systems Considering Transmission Losses

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JOURNAL OF SPACECRAFT AND ROCKETS 2023年第2期60卷 499-507页

作者： Takano, Seiichiro Ishikawa, Kazuyoshi Matsui, Makoto Shizuoka Univ Hamamatsu 4328561 Japan Dept Engn 3-5-1 JohokuNaka Ku Shizuoka Japan Dept Mech Engn 3-5-1JohokuNaka Ku Shizuoka Japan

We optimized the launch trajectory of an laser-sustained-plasma-type (LSP) laser propulsion rocket at an altitude of 500 km by considering transmission efficiency. The launch cost was calculated based on the results of trajectory calculations. The transmission loss was considered to be the effect of atmospheric turbulence and focusing the performance of the lens. In the optimization problem, the Legendre-Gauss-Lobatto (LGL) method was used for discretization, and the sequential quadratic programming method was used to solve the optimization problem. The payload ratio was 18.0% with a laser power of 200 kW. In the launch calculation, the costs of the laser, electricity, propellant, and airframe were considered for the experience curve effect. The calculation indicated the cost of 267,000 launches was 29.1% of the cost of chemical propulsion.

关键词： Propulsion System Trajectory Optimization Propellant Cost Reduction Chemical Rocket Chemical Propulsion sequential quadratic programming Airframes

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Reduced-order entry trajectory planning for acceleration guidance

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JOURNAL OF GUIDANCE CONTROL AND DYNAMICS 2002年第2期25卷 257-266页

作者： Mease, KD Chen, DT Teufel, P Schönenberger, H Univ Calif Irvine Dept Mech & Aerosp Engn Irvine CA 92697 USA Univ Stuttgart Dept Mech & Aerosp Engn D-7000 Stuttgart Germany Univ Stuttgart Inst Flight Mech & Control D-7000 Stuttgart Germany

The acceleration guidance concept is to plan an aerodynamic acceleration profile that integrates to the desired final position and velocity and satisfies all vehicle constraints and to track the acceleration profile. The longitudinal entry guidance for the space shuttle is acceleration guidance: a drag deceleration profile that integrates to the desired downrange and satisfies the vehicle constraints is planned and tracked primarily by bank-angle adjustments. The kinematics relating the drag profile to the downrange assume that the entry trajectory is a great circle arc. In this paper we consider lateral as well as longitudinal motion in acceleration planning. Three differential equations that are the kinematic relations between the aerodynamic accelerations and the position and velocity variables with energy as the independent variable are used as the basis for two methods of planning the drag and lateral acceleration profiles. The first is simpler and produces a feasible trajectory for a given angle-of-attack profile. The second requires more computation, but produces an optimal trajectory using both angle-of-attack and angle-of-bank variations to control the entry trajectory and has greater capability to shape the entry trajectory. Both methods are demonstrated using an X-33 vehicle model. The optimal method is capable of achieving a specified final heading angle and adjusting the number of bank reversals.

关键词： Angle of Attack Heading Angle Lift Forces Space Shuttle Closed Loop Optimal Control Earth Nonlinear programming Dynamic Pressure sequential quadratic programming

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Reliability-Based Design Optimization of Nonlinear Aeroelasticity Problems

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JOURNAL OF AIRCRAFT 2010年第3期47卷 992-998页

作者： Missoum, Samy Dribusch, Christoph Beran, Philip Univ Arizona Tucson AZ 85721 USA USAF Res Lab Design & Anal Methods Branch Wright Patterson AFB OH 45433 USA

This paper introduces a methodology for the reliability-based design optimization of systems with nonlinear aeroelastic constraints. The approach is based on the construction of explicit flutter and subcritical limit cycle oscillation boundaries in terms of deterministic and random design variables. The boundaries are constructed using a support vector machine that provides a way to efficiently evaluate probabilities of failure and solve the reliability-based design optimization problem. Another major advantage of the approach is that it efficiently manages the discontinuities that might appear during subcritical limit cycle oscillations. The proposed approach is applied to the construction of flutter and subcritical limit cycle oscillation boundaries for a two-degree-of-freedom airfoil with nonlinear stiffnesses. The solution of a reliability-based design optimization problem with a constraint on the probability of subcritical limit cycle oscillation is also provided.

关键词： Nonlinear Aeroelasticity Airfoil Support Vector Machine Angle of Attack sequential quadratic programming Finite Element Modeling Structural Nonlinearities Cumulative Distribution Function Radius of Gyration High Aspect Ratio

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AUGMENTED LAGRANGIAN NONLINEAR-programming ALGORITHM THAT USES SQP AND TRUST REGION TECHNIQUES

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JOURNAL OF OPTIMIZATION THEORY AND APPLICATIONS 1995年第2期86卷 311-325页

作者： PSIAKI, ML PARK, K UNIV MINNESOTA DEPT COMP SCIMINNEAPOLISMN

An augmented Lagrangian nonlinear programming algorithm has been developed. Its goals are to achieve robust global convergence and fast local convergence. Several unique strategie help the algorithm achieve these dual goals. The algorithm consists of three nested loops. The outer loop estimates the Kuhn-Tucker multipliers at a rapid linear rate of convergence. linear rate of convergence. The middle loop minimizes the augmented Lagrangian function for fixed multipliers. This loop uses the sequential quadratic programming technique with a box trust region stepsize restriction. The inner loop solves a single quadratic program. Slack variables and a constrained form of the fixed-multiplier middle-loop problem work together with curved line searches in the inner-loop problem to allow large penalty weights for rapid outer-loop convergence. The inner-loop quadratic programs include quadratic constraint terms, which complicate the inner loop, but speed the middle-loop progress when the constraint curvature is large. The new algorithm compares favorably with a commercial sequential quadratic programming algorithm on five low-order test problems. Its convergence is more robust, and its speed is not much slower.

关键词： NONLINEAR programming sequential quadratic programming AUGMENTED LAGRANGIAN TRUST REGION CONSTRAINT CURVATURE

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Experimental research on noninvasive reconstruction of optical parameter fields based on transient radiative transfer equation for diagnosis applications

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JOURNAL OF QUANTITATIVE SPECTROSCOPY & RADIATIVE TRANSFER 2019年 222卷 1-11页

作者： Qi, Hong Zhao, Fang-Zhou Ren, Ya-Tao Qiao, Yao-Bin Wei, Lin-Yang Islam, Md Arafat Ruan, Li-Ming Harbin Inst Technol Sch Energy Sci & Engn Harbin 150001 Heilongjiang Peoples R China

The noninvasive reconstruction of optical parameter fields in participating phantom is investigated experimentally based on the measured time-resolved radiative signals, which are detected by the time-correlated single-photon counting system. The discrete ordinate method is employed to solve the forward transient radiative transfer equation to simulate the time-resolved radiative transfer in the physical phantom exposed to ultra-short pulse laser irradiation. On top of that, the sequential quadratic programming algorithm based on the generalized Gaussian Markov random field is applied to solve the inverse problem. To improve the computational efficiency, an adjoint equation technique is adopted to determine the gradient of objective function. Good agreement was obtained between the predicted optical parameter fields and realistic ones. All the reconstruction results demonstrate that the proposed reconstruction methods are proved to be accurate and efficient experimentally. (C) 2018 Elsevier Ltd. All rights reserved.

关键词： Optical parameter fields reconstruction sequential quadratic programming Time-resolved radiative signals The time-correlated single-photon counting system

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Ply angle optimization of nonuniform composite beams subject to aeroelastic constraints

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AIAA JOURNAL 2000年第10期38卷 1992-1994页

作者： Evrard, T Butler, R Hughes, SW Banerjee, JR Univ Bath Dept Mech Engn Bath BA2 7AY Avon England Univ Bath Dept Mech Engn Bath BA2 7AY Avon England City Univ London Dept Aeronaut & Mech Engn London EC1V 0HB England

Studies the effect of both ply angle variation and the position of lumped massed on flutter speed for uniform thickness wind-tunnel models. Parametric study for uniform thickness beam; Optimization of nonuniform thick... 详细信息

关键词： Shear Layers Unswept Wings sequential quadratic programming Shear Deformation Young's Modulus Critical Loading Aspect Ratio Swept Wing Airspeed Aerodynamic Force

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Optimization for far-distance and fuel-limited cooperative rendezvous between two coplanar spacecraft based on Lambert method

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PROCEEDINGS OF THE INSTITUTION OF MECHANICAL ENGINEERS PART G-JOURNAL OF AEROSPACE ENGINEERING 2020年第7期234卷 1301-1310页

作者： Wang, Zhanwen Dong, Yuming Feng, Weiming Zhao, Junfeng Shandong Univ Dept Engn Mech Jinan 250062 Peoples R China

Concentrating on far-distance and fuel cooperative rendezvous between two coplanar spacecraft under impulse thrust, this paper presents fuel-optimal results obtained by optimization algorithms numerically. Former research works have formulated optimization models of multiple-impulse orbit transfer and cooperative rendezvous under continuous thrust. In this paper, optimization models of cooperative rendezvous under impulse thrust are formulated based on these former researches. The process of cooperative rendezvous is simplified by introducing a hypothetical spacecraft. The degradation from cooperative rendezvous to active-passive rendezvous is prevented by revising objective functions. Quantum-behaved particle swarm optimization and sequential quadratic programming are combined to solve a practical problem, which is used to illustrate advantages of cooperative rendezvous when fuel consumption of one spacecraft is limited.

关键词： Cooperative rendezvous trajectory optimization Lambert's problem quantum-behaved particle swarm optimization sequential quadratic programming far-distance orbit maneuver

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On the Global Convergence of a Projective Trust Region Algorithm for Nonlinear Equality Constrained Optimization

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Acta Mathematica Sinica,English Series 2018年第12期34卷 1804-1828页

作者： Yong Gang PEI De Tong ZHU Mathematics and Information Science He 'nan Normal University Xinxiang 453007 P. R. China Mathematics and Science College Shanghai Normal University Shanghai 200234 P. R. China

A trust-region sequential quadratic programming （SQP） method is developed and analyzed for the solution of smooth equality constrained optimization problems. The trust-region SQP algorithm is based on filter line search technique and a composite-step approach, which decomposes the overall step as sum of a vertical step and a horizontal step. The algorithm includes critical modifications of horizontal step computation. One orthogonal projective matrix of the Jacobian of constraint functions is employed in trust-region subproblems. The orthogonal projection gives the null space of the trans- position of the Jacobian of the constraint function. Theoretical analysis shows that the new algorithm retains the global convergence to the first-order critical points under rather general conditions. The preliminary numerical results are reported.

关键词： sequential quadratic programming trust-region filter line search projection global convergence

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Quasi-Newton corrections for compliance and natural frequency topology optimization problems

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STRUCTURAL AND MULTIDISCIPLINARY OPTIMIZATION 2023年第8期66卷 1-16页

作者： Fu, Yicong Kennedy, Graeme J. J. Georgia Inst Technol Sch Aerosp Engn Atlanta GA 30332 USA

sequential quadratic programming and interior point methods are effective general purpose optimization algorithms that sometimes exhibit poor performance in topology optimization applications. We postulate that this performance behavior stems from the frequent failure of BFGS updates for common topology optimization problem formulations that reduces the effectiveness of the resulting Hessian approximations. To address this issue, we propose a computationally efficient correction technique that utilizes problem-specific second-order derivative information to remove negative curvature contributions and achieve better overall optimizer performance. The proposed technique is tested on compliance and natural frequency topology optimization problem sets and compared against the quasi-Newton optimizers ParOpt, IPOPT, and SNOPT with the BFGS and SR1 Hessian approximations, as well as MMA. The results show that the optimizer with the proposed correction produces optimized designs in fewer function evaluations with either lower or competitive objective and discreteness metric values compared to other quasi-Newton based optimizers. Finally, scalability of the implementation is demonstrated by solving large-scale problems that have up to 96.9 million degrees of freedom with adaptively refined meshes.

关键词： Topology optimization sequential quadratic programming Quasi-Newton method

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