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Unpowered approach and landing guidance with normal acceleration limitations

JOURNAL OF GUIDANCE CONTROL AND DYNAMICS 2007年第3期30卷 882-885页

作者： Kluever, C. A. Univ Missouri Columbia MO 65211 USA

An approach and landing (A&L) guidance scheme for an unpowered reusable launch vehicle (RLV) with diminished maneuverability in the vertical plane, is presented. The guidance method computes a new reference trajectory such that load factor is minimized during the A&L phase. Trajectory planning is done by performing a series of 1-D searches by iterating on a single guidance parameter and numerically propagating multiple paths to touchdown conditions. The guidance algorithm determines the minimum constant equilibrium-glide load factor such that the flight-path angle is continually increased during the A&L phase. The corresponding A&L trajectory of the calculated minimum load factor is used as the reference path for a closed-loop guidance scheme. The guidance method is a feasible technique for onboard generation of a new reference A&L trajectory.

关键词： Flight Path Angle Reusable Launch Vehicle Airspeed Proportional Integral Derivative Lift Coefficient Aerodynamic Coefficients Numerical Integration Dynamic Pressure sequential quadratic programming Guidance Algorithms

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quadratic surface reconstruction from multiple views using SQP

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IEICE TRANSACTIONS ON INFORMATION AND SYSTEMS 2004年第1期E87D卷 215-223页

作者： Gong, RB Xu, G Ritsumeikan Univ Dept Comp Sci Kusatsu 5258577 Japan

We propose using SQP (sequential quadratic programming) to directly recover 3D quadratic surface parameters from multiple views. A surface equation is used as a constraint. In addition to the sum of squared reprojection errors defined in the traditional bundle adjustment, a Lagrangian term is added to force recovered points to satisfy the constraint. The minimization is realized by SQP. Our algorithm has three advantages. First, given corresponding features in multiple views, the SQP implementation can directly recover the quadratic surface parameters optimally instead of a collection of isolated 3D points coordinates. Second, the specified constraints are strictly satisfied and the camera parameters and 3D coordinates of points can be determined more accurately than that by unconstrained methods. Third, the recovered quadratic surface model can be represented by a much smaller number of parameters instead of point clouds and triangular patches. Experiments with both synthetic and real images show the power of this approach.

关键词： quadratic surface reconstruction constrained minimization sequential quadratic programming bundle adjustment error analysis

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Game-Based Hierarchical Cooperative Control for Electric Vehicle Lateral Stability via Active Four-Wheel Steering and Direct Yaw-Moment Control

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ENERGIES 2019年第17期12卷 3339页

作者： Zhao, Lin Lu, Shaobo Zhang, Bohan Chongqing Univ Sch Automot Engn Chongqing 400040 Peoples R China Chongqing Univ State Key Lab Mech Transmiss Chongqing 400040 Peoples R China

A Stackelberg game-based cooperative control strategy is proposed for enhancing the lateral stability of a four-wheel independently driving electric vehicle (FWID-EV). An upperlower double-layer hierarchical control structure is adopted for the design of a stability control strategy. The leaderfollower-based Stackelberg game theory (SGT) is introduced to model the interaction between two unequal active chassis control subsystems in the upper layer. In this model, the direct yaw-moment control (DYC) and the active four-wheel steering (AFWS) are treated as the leader and the follower, respectively, based on their natural characteristics. Then, in order to guarantee the efficiency and convergence of the proposed control strategy, a sequential quadratic programming (SQP) algorithm is employed to solve the task allocation problem among the distributed actuators in the lower layer. Also, a double-mode adaptive weight (DMAW)- adjusting mechanism is designed, considering the negative effect of DYC. The results of cosimulation with CarSim and Matlab/Simulink demonstrate that the proposed control strategy can effectively improve the lateral stability by properly coordinating the actions of AFWS and DYC.

关键词： active four-wheel steering direct yaw-moment control lateral stability control Stackelberg game theory sequential quadratic programming

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Fast Estimation of Perturbed Impulsive Rendezvous via Semi-Analytical Equality-Constrained Optimization

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JOURNAL OF GUIDANCE CONTROL AND DYNAMICS 2020年第12期43卷 2383-2390页

作者： Huang, An-Yi Luo, Ya-Zhong Li, Heng-Nian Natl Univ Def Technol Coll Aerosp Sci & Engn Changsha 410073 Peoples R China Xian Satellite Control Ctr State Key Lab Astronaut Dynam Xian 710043 Peoples R China Xian Satellite Control Ctr Xian Peoples R China

Researchers involved initial and final coasting arcs and obtained a contour plot of the cost versus separation angle and transfer time to find the global optimal two-impulse solution in a study. They proposed an analytical method to solve the out-of-plane rendezvous problem between two close elliptic orbits. The study described how to formulate and solve the equality-constrained optimization problem when only the right ascension of the ascending node (RAAN) difference between the chaser and target is considered using a J₂-perturbed analytical dynamics model. The equality-constrained optimization problem is first extended to include the differences of orbital semi-major axis, inclination, and RAAN together. The proposed estimation method was verified by comparing with Jet Propulsion Laboratory’s (JPL’s) champion solution for a debris removal mission and the recently reported solutions for the 2003/2005 Mars sample return (MSR) mission.

关键词： Numerical Optimization sequential quadratic programming Trajectory Optimization Mars Orbit Rendezvous Orbital Elements Jet Propulsion Laboratory Argument of Latitude Perigee FORTRAN Monte Carlo Simulation

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Displacement-based optimization for truss structures subjected to static and dynamic constraints

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AIAA JOURNAL 2002年第1期40卷 154-161页

作者： Missoum, S Gürdal, Z Virginia Polytech Inst & State Univ Dept Aerosp & Ocean Engn Blacksburg VA 24061 USA Virginia Polytech Inst & State Univ Dept Engn Sci & Mech Blacksburg VA 24061 USA

The use of displacements as design variables for truss structure optimization is considered as an alternative to the conventional finite-element-analysis-based design approach. A two-level nested optimization has been developed;in an inner level, cross-sectional areas of truss members are designed for a given displacement field, and, at an outer level, optimal displacements corresponding to the minimum weight designs are searched through the use of sequential quadratic programming. The computational efficiency of the method is, demonstrated through three examples, and the evolutions of the cross-sectional areas and optimal weight as a function of the displacements are studied. Static, dynamic, and topology problems are considered. It is shown that the method is highly efficient compared to the conventional design approaches. It is also demonstrated that the weight is always continuous throughout the design history, although areas might exhibit large discontinuities.

关键词： Planar Truss sequential quadratic programming Stiffness Matrices Structural Analysis Young's Modulus Topology Optimization Structural Optimization Composite Materials Undamped Vibrations Structural Modeling

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Guidance strategy for radially accelerated trajectories

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JOURNAL OF SPACECRAFT AND ROCKETS 2005年第4期42卷 677-683页

作者： Yamakawa, H Japan Aeroap Explorat Agcy Kanagawa 2298510 Japan

A guidance scheme is proposed for orbital motion under continuous outward radial acceleration that is inversely proportional to the square of the radial distance from the sun. Such an acceleration regime would be realized under the minimagnetospheric plasma propulsion. The maximum attainable radial distance of the outbound trajectory is investigated, and a guidance scheme for achieving this target maximum distance is established under radial acceleration disturbances. The scheme not only provides a control law for continuous radial acceleration but also yields the amount and timing of impulsive maneuvers required to satisfy the guidance requirement at the terminal point.

关键词： Astronomical Unit Space Law Earth Monte Carlo Simulation Low Thrust Propulsion Orbital Period Nonlinear programming Solar Wind Japan Aerospace Exploration Agency sequential quadratic programming

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Modeling magnetic soft continuum robot in nonuniform magnetic fields via energy minimization

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INTERNATIONAL JOURNAL OF MECHANICAL SCIENCES 2024年 282卷

作者： Li, Jiyu Wang, Liu Chinese Acad Sci Univ Sci & Technol China Dept Modern Mech Key Lab Mech Behav & Design Mat Hefei Peoples R China Chinese Acad Sci Inst Mech State Key Lab Nonlinear Mech Beijing Peoples R China

The emerging magnetic soft continuum robots (MSCRs) - a type of slender and soft rods with embedded hardmagnetic particles - hold great promise in endovascular intervention via remote magnetic actuation. Although numerous advantages of using permanent magnets have been demonstrated for manipulating MSCRs (e.g., simple systems with high actuation force, large operating workspace), the magneto-mechanical behavior of MSCRs in nonuniform magnetic fields, particularly those generated by permanent magnets, remains largely unexplored. In this work, a systematic study of MSCRs in the nonuniform field is presented, which includes theoretical modeling using hard-magnetic elastica theory, numerical analyses by energy minimization method, finite element simulations using ABAQUS user element (UEL), and experimental validation. Without solving governing differential equations, the large deflection of MSCRs is efficiently obtained via the minimization of the total potential energy using sequential quadratic programming (SQP). This efficient modeling method offers insights into the control of MSCRs using nonuniform magnetic fields. Two practical strategies are provided for precisely controlling MSCRs by manipulating a cubic magnet through the adjustment of the actuation distance, rotation angle, and spin angle, laying the foundation for applications of magnetically-assisted endovascular intervention.

关键词： Nonuniform magnetic field Magneto-mechanical behavior Energy minimization Magnetic soft continuum robot Hard-magnetic elastica sequential quadratic programming

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Simultaneous reconstruction of space-dependent optical and thermophysical parameter fields based on a laser irradiation technique

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APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING 2022年第6期128卷 514-514页

作者： Zhang, Pei Sun, Chuang Xia, Xin-Lin Wang, Fei Harbin Inst Technol Sch Energy Sci & Engn Key Lab Aerosp Thermophys MIIT 92 West Dazhi St Harbin 150001 Heilongjiang Peoples R China

A secondary reconstruction technique based on multi-section reconstruction is proposed to simultaneously reconstruct the space-dependent absorption coefficient, scattering coefficient, and thermal conductivity fields without any priori information in the participating medium. In the forward model, the finite volume method (FVM) is used to solve the coupled radiative-conductive problem. The radiative and temperature signals on one side of the medium boundary induced by laser irradiation heating are served as input measurements for the inverse analysis. In the inverse model, the sequential quadratic programming (SQP) algorithm is employed to solve the optimization problems. By this technique, more measurement signals can be obtained, which is necessary for exactly reconstructing the space-dependent optical and thermophysical parameters fields. All the retrieval results show that the proposed secondary reconstruction technique based on multi-section reconstruction can be adopted to reconstruct the complex space-dependent absorption coefficient, scattering coefficient, and thermal conductivity fields accurately and efficiently. This proposed technique will play an important role in practical application, such as non-destructive testing of materials, biology imaging in clinical medicine and optimization and design of composites.

关键词： Absorption coefficient field Scattering coefficient field Thermal conductivity field sequential quadratic programming Simultaneous reconstruction

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A zeroing neural network model for form-finding problems: A nonlinear optimization approach

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ENGINEERING APPLICATIONS OF ARTIFICIAL INTELLIGENCE 2024年 128卷

作者： Zhao, Liming Heng, Taotao Liu, Keping Sun, Zhongbo Changchun Univ Technol Dept Mech & Elect Engn Changchun 130012 Peoples R China Changchun Univ Technol Dept Control Engn Changchun 130012 Peoples R China Jilin Engn Normal Univ Sch Elect & Informat Engn Changchun 130052 Peoples R China

How to establish a simple and efficient nonlinear optimization problem form-finding model in noise environments is the main concern of this paper, thereby, a sequential quadratic programming form-finding (SQP) approach via a noise-tolerant zeroing neural network (NTZNN) is presented to solve the proposed problem. First, the rank of force density matrix is selected as optimization objective due to its crucial physical property. In addition, linear relations between the force density vectors and force density matrix are selected as the constraint conditions, which can ensure the tensegrity mechanism in a stable status. Furthermore, the simulations are shown that the presented SQP-NTZNN algorithm has superiority with anti-noise performance and computation efficiency, which by comparing the computational rate in the same noise environment with the novel form-finding algorithm. Eventually, the form-finding simulations under different initial conditions are formed to verify the importance of the constrained conditions, it can prove the high efficiency of the proposed nonlinear constrained optimization model which is transformed from the form-finding problem.

关键词： Tensegrity Form-finding Noise-tolerant zeroing neural network sequential quadratic programming Force destiny method

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Uncertainty Propagation by Linear Regression Kalman Filters for Stochastic NMPC

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IFAC-PapersOnLine 2021年第6期54卷 76-82页

作者： Rien Quirynen Karl Berntorp Mitsubishi Electric Research Laboratories Cambridge MA 02139 USA

Stochastic nonlinear model predictive control (SNMPC) allows to directly take model uncertainty into account, e.g., by including probabilistic chance constraints. This paper proposes linear-regression Kalman filtering to perform high-accuracy propagation of mean and covariance information for the nonlinear system dynamics in a tractable approximation of the stochastic optimal control problem. In addition, a tailored adjoint-based sequential quadratic programming (SQP) algorithm is presented to considerably reduce the computational cost and allow a real-time implementation of the resulting SNMPC. The prediction accuracy and control performance of the proposed approach are illustrated on a vehicle control application subject to external disturbances, while highlighting a worst-case computation time of 10 ms for SNMPC which is close to that of deterministic NMPC for this particular case study.

关键词： Stochastic nonlinear model predictive control linear-regression Kalman filtering sequential quadratic programming real-time optimization algorithms

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