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Aircraft Optimal Separation Allocation Based on Global Optimization Algorithm

Transactions of Nanjing University of Aeronautics and Astronautics 2022年第6期39卷 707-720页

作者： REN Xuanming TANG Xinmin College of Civil Aviation Nanjing University of Aeronautics and AstronauticsNanjing 211106P.R.China College of Transportation Science and Engineering Civil Aviation University of ChinaTianjin 300300P.R.China

A dynamic programming-sequential quadratic programming(DP-SQP)combined algorithm is proposed to address the problem that the traditional continuous control method has high computational complexity and is easy to fall into local optimal *** solve the globally optimal control law sequence,we use the dynamic programming algorithm to discretize the separation control decision-making process into a series of sub-stages based on the time characteristics of the separation allocation model,and recursion from the end stage to the initial *** sequential quadratic programming algorithm is then used to solve the optimal return function and the optimal control law for each *** simulations of the combined algorithm and the traditional algorithm are designed to validate the superiority of the combined ***-following and cross-conflict simulation examples are created to demonstrate the combined algorithm’s adaptability to various conflict *** simulation results demonstrate the separation deploy strategy’s effectiveness,efficiency,and adaptability.

关键词： optimal separation allocation sequential quadratic programming dynamic programming globally optimal control optimal control law

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On a cellular developmental method for layout optimization via multi-fidelity analyses and the two-point topological derivative

On a cellular developmental method for layout optimization v...

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AIAA Aviation Forum and Exposition

作者： Kobayashi, Marcelo H. Canfield, Robert A. Kolonay, Raymond M. Univ Hawaii Manoa Dept Mech Engn 2540 Dole StHolmes Hall 302 Honolulu HI 96822 USA Virginia Polytech Inst & State Univ Kevin T Crofton Dept Aerosp & Ocean Engn Randolph HallRm 214460 Old Turner StMC 0203 Blacksburg VA 24061 USA Air Force Res Lab Multidisciplinary Sci & Technol Ctr 2210 8th StBldg 146Room 218 Wright Patterson AFB OH 45433 USA

ISBN: (数字)9781624106101

ISBN: (纸本)9781624106101

Handling multidisciplinary responses during structural topology optimization is important to a field that has grown rapidly in the last decade, spurred by additive manufacturing and 3D printing. The cellular division method for topological design is more general than conventional optimality criterion methods used most often in industrial structural topology design;however, it is a discrete approach that is daunting due to the curse of dimensionality. The innovative approach presented here formulates the design problem as a more tractable gradient-based one that exploits a new two-point topological derivative. Promising results are presented for benchmark test cases using the multi-fidelity approach using two-point topological derivatives to drive cellular development.

关键词： Topology Optimization Shape Optimization Cantilever Poisson's Ratio sequential quadratic programming Stress Distribution Energy Distribution Evolutionary Algorithm Structural Analysis Aspect Ratio

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Use of Control Systems in the Correction of Static and Thermal Aberrations

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JOURNAL OF SURFACE INVESTIGATION 2023年第SUPPL 1期17卷 S244-S249页

作者： Petrakov, E. V. Chkhalo, N. I. Russian Acad Sci Inst Phys Microstruct Nizhnii Novgorod 603950 Russia

Growth in the power of laser systems and synchrotron emitters increases the need for adaptive optical systems to form wavefronts of the required quality. The correction of static aberrations is implemented using deformable mirrors, and phase distortions due to the heating of active elements (bumps) are corrected by cooling radiator systems. Mirrors are deformed either by a system of a large number of piezoelectric actuators, which, when voltage is applied, generate transverse forces of the order of kN and displacements of tens of microns, or by means of attached piezoelectric bimorphs, which create a small bending moment (about 1 N m), but have the ability to move by millimeters. The number of degrees of freedom of a deformable mirror is related to the number of piezoelectric drives, and, accordingly, to the complexity of theoretical and practical implementation. In the course of this work, we will consider the problem of static aberrations and distortions due to heating as a control problem using a system of piezoelectric bimorphs and piezoelectric actuators. To search for the optimal parameters of the actuators, the method of optimization of sequential quadratic programming will be used, which satisfies the limitations of piezoelectric actuators. The standard deviation for the entire reflective element relative to the required shape will be taken as the minimization criterion.

关键词： adaptive optical systems phase distortions deformable mirrors piezoelectric bimorphs piezoelectric actuators sequential quadratic programming thermal aberrations static aberrations optimization mathematical model of deformation synchrotron radiation laser systems

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A Bayesian Approach to Collaborative Optimization with Application to Tailless Aircraft Range Maximization

A Bayesian Approach to Collaborative Optimization with Appli...

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AIAA Aviation Forum and Exposition

作者： de Becdelievre, Jean Kroo, Ilan Stanford Univ Dept Aeronaut & Astronaut Stanford CA 94305 USA

ISBN: (数字)9781624106101

ISBN: (纸本)9781624106101

Collaborative Optimization is a two-level design optimization architecture that allows the solution of multidisciplinary problems as a series of single-disciplinary problems with very little infrastructure overhead. It can be a very practical option in cases where practitioners do not have a fully coupled multidisciplinary optimizers at hand, but have access to multiple single-disciplinary optimizers. However, in its current form the method can require a large number of single-disciplinary evaluations and be slow to converge. In this work, we propose an improvement to the original method. We show how, at each iteration of the Collaborative Optimization framework, orthogonal projections on the feasible set of every discipline are performed. Mimicking the Bayesian Optimization framework, we propose to learn probabilistic representations of the feasible sets with the projection information, and use them to choose the next sample point in a principled manner. We also show that ensembles of Lipshitz neural networks are well performing probabilistic representations in this case. The approach is applied to a tailless aircraft range maximization problem.

关键词： Tailless Aircraft Feedforward Neural Network Bayesian Optimization Bayesian Approach Lift Distribution Lift Coefficient Surrogate Model Probability Distribution sequential quadratic programming Multidisciplinary Design Optimization

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Flying Complex Maneuvers with Model Predictive Path Integral Control

Flying Complex Maneuvers with Model Predictive Path Integral...

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AIAA Science and Technology Forum and Exposition (AIAA SciTech Forum)

作者： Pravitra, Jintasit Theodorou, Evangelos A. Johnson, Eric N. Georgia Inst Technol Sch Aerosp Engn Atlanta GA 30332 USA Penn State Univ Dept Aerosp Engn University Pk PA 16802 USA

ISBN: (数字)9781624106095

ISBN: (纸本)9781624106095

The model predictive path integral (MPPI) control algorithm is applied to fixed-wing aircraft. Because MPPI imposes no restriction on the form of the cost function, arbitrarily complex maneuvers can be crafted through cost function design. MPPI works by propagating (thousands of) trajectories forward in time using random control inputs. This procedure is done in parallel using a graphics processing unit (GPU). The optimal control is computed by weight-averaging the controls from these trajectories (with each weight corresponds to the respective trajectory cost). A nonlinear wind-axes aircraft model is used in the MPPI propagation step. This choice of model offers two benefits. First, the model remains nonlinear which is appropriate for aggressive flights. Second, the model does not require parameters. Prediction error due to parametric uncertainty can be eliminated. We demonstrate our method in a simulated air racing scenario. Despite the simulated result, the real-time feasibility is validated because 1) the implementation is done in a flight-capable software framework, and 2) the simulation is done in a high fidelity flight dynamics simulator. We show that MPPI offers superior performances compared to a typical waypoint guidance. These include a smaller altitude drop in tight turns, a better ability to stay on course, and a lower maximum load factor.

关键词： Trajectory Optimization Fixed Wing Aircraft Air Racing Graphics Processing Unit Control Algorithm Flight Dynamics Model Predictive Control Autopilot sequential quadratic programming Parallel Computing Framework

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Non-Stochastic Robust Design of Airfoils - a New Paradigm

Non-Stochastic Robust Design of Airfoils - a New Paradigm

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AIAA Science and Technology Forum and Exposition (AIAA SciTech Forum)

作者： Piperni, Pat Tricic, Almir Clarkson Univ Mech & Aeronaut Engn Dept Potsdam NY 13699 USA

ISBN: (数字)9781624106095

ISBN: (纸本)9781624106095

Uncertainties inherent in aircraft manufacturing and operations can have significant impact on performance. These include manufacturing deviations, in-service wear-and-tear, uncertainty in ambient flight conditions, variations in control-surface rigging and deflections under load, and the effects of ice and non-ice contamination. It is therefore imperative to develop design processes that strike the right balance between robustness and performance. However, the application of robust design techniques using high-fidelity aerodynamic analysis is still prohibitively expensive. The main reason for this is that robust design processes typically employ statistical distributions to model uncertainties, and relatively large sample sizes are required to obtain accurate estimates of the moments of the distributions. The consequence of this is that the resources required to complete a robust design optimization can be orders of magnitude greater than that required for deterministic optimizations, unless reduced-order or surrogate modeling is employed. In the work presented herein, a novel non-stochastic approach is proposed to enforce design robustness. This is accomplished by constraining the second derivative of the design objective with respect to the design variables, thereby removing the need for uncertainty propagation in the design process. Sample optimizations are included to demonstrate the viability of the new approach, in which robust airfoil designs are achieved in a small fraction of the time and resources required by traditional methods.

关键词： Robust Design Airfoil Statistical Distributions Surrogate Model Aircraft Manufacturing Lift to Drag Ratio Shape Functions Monte Carlo Simulation Airfoil Geometry sequential quadratic programming

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High-Order Implicit Shock Tracking with Targeted Mesh Optimization and PDE-Based Smoothing

High-Order Implicit Shock Tracking with Targeted Mesh Optimi...

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AIAA Aviation Forum and Exposition

作者： Huang, Tianci Zahr, Matthew J. Univ Notre Dame Dept Aerosp & Mech Engn 321 Cushing Hall Notre Dame IN 46556 USA Univ Notre Dame Dept Aerosp & Mech Engn 300B Cushing Hall Notre Dame IN 46556 USA

ISBN: (数字)9781624106101

ISBN: (纸本)9781624106101

Implicit shock tracking is a class of numerical methods to approximate solutions of conservation laws with non-smooth features, e.g., contact lines, shock waves, and rarefactions. These methods align elements of the computational mesh with non-smooth features to represent them perfectly, allowing high-order basis functions to approximate smooth regions of the solution without the need for nonlinear stabilization, which leads to accurate approximations on traditionally coarse meshes. In this work, instead of optimizing over all nodal coordinates of the mesh during the implicit tracking iterations, we select a subset of the nodal degrees of freedom to optimize to reduce the cost per iteration of implicit tracking. The remaining nodal coordinates are determined using PDE-based smoothing. This approach effectively reduces the size of the linear system that must be solved at each optimization iteration without sacrificing solution and mesh quality. It has the added benefit of reducing unnecessary mesh motion, which accelerates convergence to an aligned mesh. The approach is demonstrated using two-dimensional test cases, one of which is compressible flow over a diamond in a tunnel that features a complex flow field with reflecting, intersecting, and curved shocks.

关键词： Curved Shocks Compressible Flow Dirichlet Boundary Condition Linear Elasticity Rankine Hugoniot Conditions sequential quadratic programming Total Variation Diminishing Stiffness Matrices Discontinuous Galerkin Method Mesh Parameterization

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Numerical treatment for the nonlinear fifth kind of multi-singular differential model: a neuro-swarming approach

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PHYSICA SCRIPTA 2022年第7期97卷 075203-075203页

作者： Sabir, Zulqurnain Ali, Mohamed R. Alhazmi, Sharifah E. Raja, Muhammad Asif Zahoor Sadat, R. Hazara Univ Dept Math & Stat Mansehra Pakistan Future Univ Fac Engn & Technol Cairo Egypt Benha Univ Benha Fac Engn Basic Engn Math Dept Banha Egypt Umm Al Qura Univ Al Qunfudah Univ Coll Math Dept Mecca Saudi Arabia Natl Yunlin Univ Sci & Technol Future Technol Res Ctr 123 Univ RdSect 3 Touliu 64002 Yunlin Taiwan Zagazig Univ Zagazig Fac Engn Dept Math Zagazig Egypt

In this study, a numerical scheme is proposed for the fifth order (FO) singular differential model (SDM), FO-SDM. The solutions of the singular form of the differential models are always considered difficult to solve and huge important in astrophysics. A neural network study together with the hybrid combination of global particle swarm optimization and local sequential quadratic programming schemes is provided to find the numerical simulations of the FO-SDM. An objective function is constructed using the differential FO-SDM along with the boundary conditions. The correctness of the scheme is observed by providing the comparison of the obtained and exact solutions. The justification of the proposed scheme is authenticated in terms of absolute error (AE), which is calculated in good measures for solving the FO-SDM. The efficiency and reliability of the stochastic approach are observed using the statistical performances to solve the FO-SDM.

关键词： fifth order singular models neural network sequential quadratic programming particle swarm optimization statistical measures

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Predictive Cruise Control of Full Electric Vehicles: A Comparison of Different Solution Methods 6th

Predictive Cruise Control of Full Electric Vehicles: A Compa...

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6th IFAC Conference on Engine Powertrain Control, Simulation and Modeling (E-COSM)

作者： Chu, Hongqing Dong, Shiying Hong, Jinlong Chen, Hong Gao, Bingzhao Tongji Univ Sch Automot Studies Shanghai Peoples R China Jilin Univ Dept Control Sci & Engn Chuangchun Peoples R China

The integration of electrification and intelligence is of great significance to alleviating range anxiety of electric vehicles. Predictive cruise control (PCC), which optimizes the longitudinal driving strategies by using the upcoming road traffic information, can further improve the vehicle economy. The paper gives the comparison of different solution methods regarding PCC problem of electric vehicles. The car-following optimization problem is formulated as a constrained nonlinear optimization problem. For ease of presentation, the car-following optimization problem is reformulated as a standard form of the optimization problem in continuous time domain. Then, the standard form of the optimization problem is transformed from a continuous form to a discrete form by using Euler method and Gauss pseudospectral method. Two common solution methods, that is dynamic programming and sequential quadratic programming, are used to solve the optimization problem in discrete form. Simulations are performed to demonstrate the comparison of different solution schemes. Copyright (C) 2021 The Authors.

关键词： Predictive cruise control electric vehicle model predictive control Euler method Gauss pseudospectral method dynamic programming sequential quadratic programming

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A Post-Flutter Response Constraint for Gradient-Based Aircraft Design Optimization

A Post-Flutter Response Constraint for Gradient-Based Aircra...

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AIAA Aviation Forum and Exposition

作者： Riso, Cristina Cesnik, Carlos E. S. Epureanu, Bogdan, I Teufel, Patrick Univ Michigan Dept Aerosp Engn 1320 Beal Ave Ann Arbor MI 48109 USA Univ Michigan Dept Mech Engn 2350 Hayward St Ann Arbor MI 48109 USA Airbus Operat GmbH Blagnac France

ISBN: (数字)9781624106101

ISBN: (纸本)9781624106101

Considering flutter as a constraint in aircraft design optimization has the potential to enable energy-efficient vehicle designs with high-aspect-ratio wings while meeting flutter requirements early in the design cycle. However, nonlinear aeroelastic effects in high-aspect-ratio wings may cause self-sustained oscillations to arise even before flutter occurs (subcritical bifurcation). To address this problem, this paper presents a novel post-flutter response constraint for gradientbased aircraft design optimization. The constraint prevents self-sustained oscillations inside the flight envelope independent of the flutter boundary. Moreover, it avoids transient or iterative calculations and can handle discontinuities due to mode switches and hump modes. The formulation is demonstrated by optimizing a typical aeroelastic section with a nonlinear torsion spring and an initially subcritical bifurcation. The results show that the post-flutter response constraint suppresses the subcritical bifurcation while keeping the flutter constraint active, so avoiding a conservative solution.

关键词： Aircraft Design High Aspect Ratio Flight Envelope Transient Response Nonlinear Aeroelastic Systems Computing Stiffness Matrices Structural Damping Aerodynamic Shape Optimization sequential quadratic programming

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