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Analysis of Along-Track Variable Wind Effects on Optimal Aircraft Trajectory Generation

JOURNAL OF GUIDANCE CONTROL AND DYNAMICS 2016年第9期39卷 2149-2156页

作者： Valenzuela, Alfonso Rivas, Damian Univ Seville Dept Aerosp Engn Escuela Tecn Super Ingn Seville 41092 Spain

A study is conducted to advance in the understanding of the influence of variable winds on optimal aircraft trajectories, and, as a consequence, the influence on trajectory planning. Multiphase aircraft trajectories with a stepped climb cruise at different altitudes are analyzed. Of particular interest is to understand how the optimum cruise altitudes are affected by vertical wind shear and by along-track wind speed variation and how these variations depend on the CI. To optimize the trajectories a parametric optimization approach is considered, which takes into account the existence of multiple local minima.

关键词： Aircraft Trajectory Cruise Altitude Calibrated Airspeed Aerodynamic Drag Stratosphere Wind Shear Fuel Consumption Direct Operating Cost Experimental Flight Management System sequential quadratic programming

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Discrete Mechanics for 1-dimensional Distributed Parameter Mechanical Systems under Free Boundary Conditions and Its Application to Vibration Suppression Control of Free-fixed Strings 56

Discrete Mechanics for 1-dimensional Distributed Parameter M...

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56th Annual Conference of the Society-of-Instrument-and-Control-Engineers-of-Japan (SICE)

作者： Kai, Tatsuya Yamaki, Kouhei Tokyo Univ Sci Grad Sch Ind Sci & Technol Tokyo Japan

ISBN: (纸本)9784907764579

This study develops discrete mechanics for 1-dimensional distributed parameter mechanical systems under free boundary conditions, and a control method for the systems based on a blending method of discrete mechanics and nonlinear optimization. First, under the assumption on free boundary conditions, discrete Euler-Lagrange equations and boundary equations are derived by discrete Hamilton's principle. Next, for the discrete Euler-Lagrange equations with control inputs and boundary equations, a nonlinear optimal control problem with constraints by setting an objective function, and initial and boundary conditions is formulated. Then, a vibration suppression control problem for a free-fixed string is considered as a physical example. As a result, it turns out that vibration of the string is suppressed and the whole of the system is stabilized by the proposed method.

关键词： Distributed Parameter Mechanical Systems Discrete Mechanics Free boundary Condition Nonlinear Optimization sequential quadratic programming Stabilization Control Free-Fixed String

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Optimal Trajectories for Planetary Pole-Sitter Missions

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JOURNAL OF GUIDANCE CONTROL AND DYNAMICS 2016年第10期39卷 2456-2465页

作者： Walmsley, Mike Heiligers, Jeannette Ceriotti, Matteo McInnes, Colin Univ Edinburgh Sch Phys & Astron James Clerk Maxwell Bldg Edinburgh EH9 3FD Midlothian Scotland Delft Univ Technol Fac Aerosp Engn Kluyverweg 1 NL-2629 HS Delft Netherlands Univ Glasgow Sch Engn James Watt South Bldg Glasgow G12 8QQ Lanark Scotland Univ Glasgow Sch Engn Engn Sci James Watt South Bldg Glasgow G12 8QQ Lanark Scotland

A study tries to understand the broad impact of the target planet on the efficacy of a pole-sitter mission. Key mission criteria will be mass use and separation from target. The pole sitter is modeled within the circular restricted three-body problem (CR3BP) in which the Sun and the target planet are assumed to move in circular paths around their common center of mass and the impact of the satellite on the motion of both the Sun and the target planet is neglected. The basic idea of a pole-sitter satellite is that it remains directly above a planetary pole at all times.

关键词： Earth Solar Electric Propulsion Propellant Satellites Hybrid Propulsion Diminishing Returns Fuel Consumption Non Keplerian Orbit Winter Solstice sequential quadratic programming

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Aerodynamic Optimization Based on Continuous Adjoint Method for a Flexible Wing

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INTERNATIONAL JOURNAL OF AEROSPACE ENGINEERING 2016年第Pt.2期2016卷 4706925.1-4706925.1页

作者： Xu, Zhaoke Xia, Jian Nanjing Univ Aeronaut & Astronaut Coll Aerosp Engn Nanjing 210016 Jiangsu Peoples R China

Aerodynamic optimization based on continuous adjoint method for a flexible wing is developed using FORTRAN 90 in the present work. Aerostructural analysis is performed on the basis of high-fidelity models with Euler equations on the aerodynamic side and a linear quadrilateral shell element model on the structure side. This shell element can deal with both thin and thick shell problems with intersections, so this shell element is suitable for the wing structural model which consists of two spars, 20 ribs, and skin. The continuous adjoint formulations based on Euler equations and unstructured mesh are derived and used in the work. sequential quadratic programming method is adopted to search for the optimal solution using the gradients from continuous adjoint method. The flow charts of rigid and flexible optimization are presented and compared. The objective is to minimize drag coefficient mean while maintaining lift coefficient for a rigid and flexible wing. A comparison between the results from aerostructural analysis of rigid optimization and flexible optimization is shown here to demonstrate that it is necessary to include the effect of aeroelasticity in the optimization design of a wing.

关键词： Wings Adjoint matrix LIFT COEFFICIENTS Euler equations Optimal design unstructured grids (mathematics) aeroelasticity high fidelity shell element Rigid flexible airfoils sequential quadratic programming

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Optimization of multi-product economic production quantity model with partial backordering and physical constraints: SQP, SFS, SA, and WCA

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APPLIED SOFT COMPUTING 2016年 49卷 770-791页

作者： Khalilpourazari, Soheyl Pasandideh, Seyed Hamid Reza Niaki, Seyed Taghi Akhavan Kharazmi Univ Fac Engn Dept Ind Engn Tehran Iran Sharif Univ Technol Dept Ind Engn Tehran Iran

A multi-product economic production quantity model with several real-world technical and physical constraints is developed in this paper. The cost function includes ordering, holding, backordering, lost sale, and the cost caused by unused space in the warehouse. The goal is to minimize the total inventory cost, where shortages are allowed and partially backordered with fixed and linear costs. The aim is to determine the length of the inventory cycle, the length of positive inventory period, and the backordering rates of the products during the shortage period in order to minimize the total inventory costs while satisfying all constraints. Due to complexity and non-linearity of the proposed model, sequential quadratic programming (SQP), stochastic fractal search (SFS), simulated annealing (SA), and water cycle algorithm (WCA) are utilized for solution. Ninety numerical examples in small, medium, and large sizes are solved to evaluate the efficiency of the solution methods. The performances of the solution methods are compared statistically. Besides, sensitivity analysis is performed to determine the effect of change in the main parameters of the problem on the objective function value and decision variables. (C) 2016 Elsevier B.V. All rights reserved.

关键词： Economic production quantity Partial backordering sequential quadratic programming Stochastic fractal search Simulated annealing Water cycle algorithm

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Automatic calibration of fundamental diagram for first-order macroscopic freeway traffic models

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JOURNAL OF ADVANCED TRANSPORTATION 2016年第3期50卷 363-385页

作者： Zhong, Renxin Chen, Changjia Chow, Andy H. F. Pan, Tianlu Yuan, Fangfang He, Zhaocheng Sun Yat Sen Univ Sch Engn Guangzhou 510275 Guangdong Peoples R China Guangdong Prov Key Lab Intelligent Transportat Sy Guangzhou Guangdong Peoples R China Guangzhou Publ Transport Data Management Ctr Guangzhou Guangdong Peoples R China UCL Dept Civil Environm & Geomat Engn London England Hong Kong Polytech Univ Dept Civil & Environm Engn Hong Kong Hong Kong Peoples R China Sun Yat Sen Univ Sch Informat Sci & Technol Dept Automat Control Guangzhou 510275 Guangdong Peoples R China

Despite its importance in macroscopic traffic flow modeling, comprehensive method for the calibration of fundamental diagram is very limited. Conventional empirical methods adopt a steady state analysis of the aggregate traffic data collected from measurement devices installed on a particular site without considering the traffic dynamics, which renders the simulation may not be adaptive to the variability of data. Nonetheless, determining the fundamental diagram for each detection site is often infeasible. To remedy these, this study presents an automatic calibration method to estimate the parameters of a fundamental diagram through a dynamic approach. Simulated flow from the cell transmission model is compared against the measured flow wherein an optimization merit is conducted to minimize the discrepancy between model-generated data and real data. The empirical results prove that the proposed automatic calibration algorithm can significantly improve the accuracy of traffic state estimation by adapting to the variability of traffic data when compared with several existing methods under both recurrent and abnormal traffic conditions. Results also highlight the robustness of the proposed algorithm. The automatic calibration algorithm provides a powerful tool for model calibration when freeways are equipped with sparse detectors, new traffic surveillance systems lack of comprehensive traffic data, or the case that lots of detectors lose their effectiveness for aging systems. Furthermore, the proposed method is useful for off-line model calibration under abnormal traffic conditions, for example, incident scenarios. Copyright (c) 2015 John Wiley & Sons, Ltd.

关键词： the cell transmission model (CTM) fundamental diagram calibration and validation nonlinear programming least square (LS) sequential quadratic programming

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Off-line programming of six-axis robots for optimum five-dimensional tasks

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MECHANISM AND MACHINE THEORY 2016年 100卷 155-169页

作者： Leger, J. Angeles, J. McGill Univ Montreal PQ Canada

Five-degree-of-freedom (five-dof) tasks are of particular interest in industry, since machining, arc-welding and deburring operations all fall into this category. These tasks, normally conducted with industrial six-dof robots, render the robot functionally redundant. Upon exploiting this redundancy to minimize the condition number of the Jacobian matrix, it is expected that the accuracy of the performed task will be increased. Traditional methods for redundancy-resolution are normally used to solve the more frequent intrinsic redundancy;however, they are not applicable to functional redundancy. Five-dof tasks are formulated using an approach that leads to a system of six velocity-level kinematics relations in six unknowns, with a 6x6 Jacobianmatrix, of nullity 1, which reflects the functional redundancy of the problem at hand. To resolve the foregoing redundancy, a method based on sequential quadratic programming (SQP) is proposed. A novel method to compute the gradient of the condition number is also discussed, as it is a key element for finding the posture of minimum condition number using a gradient method. An example then shows how the SQP algorithm can be applied to offline robot trajectory-planning for five-dof tasks. In this example, a comparison is also made between the quasi-Newton and the Newton-Raphson methods to find the posture of minimum condition number for the robot. This is an essential step in finding the trajectory of minimum condition number. (C) 2016 Published by Elsevier Ltd.

关键词： sequential quadratic programming Redundancy-resolution Functional redundancy Trajectory planning Condition number

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NONLINEAR PRECONDITIONING TECHNIQUES FOR FULL-SPACE LAGRANGE-NEWTON SOLUTION OF PDE-CONSTRAINED OPTIMIZATION PROBLEMS

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SIAM JOURNAL ON SCIENTIFIC COMPUTING 2016年第5期38卷 A2756-A2778页

作者： Yang, Haijian Hwang, Feng-Nan Cai, Xiao-Chuan Hunan Univ Coll Math & Econometr Changsha 410082 Hunan Peoples R China Natl Cent Univ Dept Math Taoyuan 32001 Taiwan Univ Colorado Dept Comp Sci Boulder CO 80309 USA

The full-space Lagrange-Newton algorithm is one of the numerical algorithms for solving problems arising from optimization problems constrained by nonlinear partial differential equations. Newton-type methods enjoy fast convergence when the nonlinearity in the system is well-balanced;however, for some problems, such as the control of incompressible flows, even linear convergence is difficult to achieve and a long stagnation period often appears in the iteration history. In this work, we introduce a nonlinearly preconditioned inexact Newton algorithm for the boundary control of incompressible flows. The system has nine field variables, and each field variable plays a different role in the nonlinearity of the system. The nonlinear preconditioner approximately removes some of the field variables, and as a result, the nonlinearity is balanced and inexact Newton converges much faster when compared to the unpreconditioned inexact Newton method or its two-grid version. Some numerical results are presented to demonstrate the robustness and efficiency of the algorithm.

关键词： PDE-constrained optimizations flow control nonlinear elimination preconditioner inexact Newton method sequential quadratic programming

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A quasi-static interface damage model with cohesive cracks: SQP-SGBEM implementation

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ENGINEERING ANALYSIS WITH BOUNDARY ELEMENTS 2016年 62卷 123-140页

作者： Vodicka, Roman Tech Univ Kosice Fac Civil Engn Kosice 04200 Slovakia

A quasi-static model for crack-mode sensitive interface damage with linearly elastic bodies at small strains is developed. It invokes a cohesive type response of the interface interpreted as a thin layer of an adhesive. The damage model is defined with the aim to obtain stress-strain relations in the cohesive zone typically employed in engineering interface-models. The weak solution of the problem is sought numerically by a semi-implicit time-stepping procedure which uses recursive double minimization in displacements and damage separately. The spatial discretization is performed by the symmetric Galerkin boundary-element method. quadratic and sequential quadratic programming are implemented to resolve each partial minimization of the recursive scheme in the computation of the time-discretized solutions. Sample 2D numerical examples demonstrate applicability of the model as well as efficiency of the SGBEM and convex programming numerical implementations. (C) 2015 Elsevier Ltd. All rights reserved.

关键词： Cohesive contact Debonding Delamination Interface fracture Interface damage Mixed mode crack Symmetric Galerkin BEM sequential quadratic programming

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A Trust Region SQP Method for Coordinated Voltage Control in Smart Distribution Grid

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IEEE TRANSACTIONS ON SMART GRID 2016年第1期7卷 381-391页

作者： Sheng, Wanxing Liu, Ke-yan Cheng, Sheng Meng, Xiaoli Dai, Wei China Elect Power Res Inst Beijing 100192 Peoples R China

This paper investigates the coordinated voltage control problem for smart distribution grid with the integration of distributed generation (DG). By actively participating in voltage control together with under-load tap changer and shunt capacitors, DG can operate more effectively in the distribution network. The objective of the proposed control method is to minimize the active power loss in the distribution system and to decrease the number of switching device operations while maintaining the grid voltage within the allowable range. Nondispatchable and dispatchable DG are both considered in the control method. To solve the mixed integer nonlinear programming problem, the trust region sequential quadratic programming method is integrated with the branch and bound approach to iteratively approximate the optimization with trust region guidance. Numerical tests on a standard 10-kV distribution system, a real 10-kV distribution system in the Sichuan province of China, and the IEEE 13-bus demonstrate the applicability of the proposed coordinated voltage control method.

关键词： Coordinated voltage control distribution generation (DG) sequential quadratic programming smart distribution grid

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