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Rapid transfer alignment for SINS of carrier craft

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Journal of Systems Engineering and Electronics 2013年第2期24卷 303-308页

作者： Jingshuo Xu Yongjun Wang Zhicai Xiao Qingdao Campus of Naval Aeronautical and astronautical University department of Control Engineering Naval Aeronautical and Astronautical University

In order to improve the survival ability and rapid response ability of the carrier craft,a new rapid transfer alignment method of the strapdown inertial navigation system（SINS） on a rocking base is put *** the method,the aircraft carrier does not need any form of ***,interfering motions such as rolling,pitching,and yawing motions caused by sea waves are effectively ***,the deck flexure deformation model is ***,the state space model of transfer alignment is ***,the feasibility of this method is validated by the *** results show that the misalignment angle error can be estimated and reach an anticipated precision-0.2 mrad in 5 s,while the deck deformation angle error can be estimated and reach a better precision- 0.1 mrad in 20 s.

关键词： strapdown inertial navigation system(SINS) transfer alignment carrier aircraft carrier moored.

Guidance law with impact time and impact angle constraints

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Chinese Journal of Aeronautics 2013年第4期26卷 960-966页

作者： Zhang Youan Ma Guoxin Liu Aili department of Control Engineering Naval Aeronautical and Astronautical University

A novel closed-form guidance law with impact time and impact angle constraints is pro- posed for salvo attack of anti-ship missiles, which employs missile＇s normal acceleration （not jerk） as the control command directly. Firstly, the impact time control problem is formulated as tracking the designated time-to-go （the difference between the designated impact time and the current flight time） for the actual time-to-go of missile, and the impact angle control problem is formulated as tracking the designated heading angle for the actual heading angle of missile. Secondly, a biased proportional navigation guidance （BPNG） law with designated heading angle constraint is constructed, and the actual time-to-go estimation for this BPNG is derived analytically by solving the system differential equations. Thirdly, by adding a feedback control to this constructed BPNG to eliminate the time-to-go errorthe difference between the standard time-to-go and the actual time-to-go, a guidance law with adjustable coefficients to control the impact time and impact angle simultaneously is developed. Finally, simulation results demonstrate the performance and feasibility of the proposed approach.

关键词： Feedback control Guidance law Impact angle Impact time Missiles Proportional navigation guidance

Lifetime prediction based on Gamma processes from accelerated degradation data

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Chinese Journal of Aeronautics 2015年第1期28卷 172-179页

作者： Wang Haowei Xu Tingxue Mi Qiaoli Graduate Students’ Brigade Naval Aeronautical and Astronautical University department of Ordnance Science and Technology Naval Aeronautical and Astronautical University

Accelerated degradation test is a useful approach to predict the product lifetime at the normal use stress level, especially for highly reliable products. Two kinds of the lifetime prediction based on Gamma processes were studied. One was to predict the lifetime of the population from accelerated degradation data, and the other was to predict the lifetime of an individual by taking the accelerated degradation data as prior information. For an extensive application, the Gamma process with a time transformation and random effects was considered. A novel contribution is that a deducing method for determining the relationships between the shape and scale parameters of Gamma processes and accelerated stresses was presented. When predicting the lifetime of an individual, Bayesian inference methods were adopted to improve the prediction accuracy, in which the conjugate prior distribution and the non-conjugate prior distribution of random parameters were studied. The conjugate prior distribution only considers the random effect of the scale parameter while the non-conjugate prior distribution considers the random effects of both the scale and shape parameter. The application and usefulness of the proposed method was demonstrated by the accelerated degradation data of carbon-film resistors.

关键词： conjugate accelerated prior lifetime Bayesian determining illustrated likelihood acceleration fitting

A distributed cooperative guidance law for salvo attack of multiple anti-ship missiles

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Chinese Journal of Aeronautics 2015年第5期28卷 1438-1450页

作者： Zhang Youan Wang Xingliang Wu Huali department of Control Engineering Naval Aeronautical and Astronautical University

The consensus problem of impact time is addressed for multiple anti-ship missiles. A new distributed cooperative guidance law with the form of biased proportional navigation guidance （BPNG） is presented. The proposed guidance law employs the available measurements of relative impact time error as the feedback information to achieve the consensus of impact time among mis- siles and, by exploiting the special structure of the biased cooperative control term, it can handle the seeker＇s field-of-view （FOV） constraint. The proposed scheme ensures convergence to consensus of impact time under either fixed or switching sensing/communication network, and the topological requirements are less restrictive than those in the existing results. Numerical examples are provided to illustrate the effectiveness of the proposed guidance law.

关键词： Cooperative Distributed Field-of-view constraint Missile guidance Missile trajectory control

Highly maneuvering target tracking using multi-parameter fusion Singer model

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Journal of Systems Engineering and Electronics 2017年第5期28卷 841-850页

作者： Shuyi Jia Yun Zhang Guohong Wang Research Institute of Information Fusion Naval Aeronautical and Astronautical University department of Aircraft Engineering Naval Aeronautical and Astronautical University

An algorithm of highly maneuvering target tracking is proposed to solve the problem of large tracking error caused by strong maneuver. In this algorithm, a new estimator, named as multi-parameter fusion Singer (MF-Singer) model is derived based on the Singer model and the fuzzy reasoning method by using radial acceleration and velocity of the target, and applied to the problem of maneuvering target tracking in strong maneuvering environment and operating environment. The tracking performance of the MF-Singer model is evaluated and compared with other manuevering tracking models. It is shown that the MF-Singer model outperforms these algorithms in several examples.

关键词： maneuvering target multi-parameter fusion Singer (MF-Singer) fuzzy reasoning Singer model

Distributed H_∞ control of multi-agent systems with directed networks

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Chinese Physics B 2015年第9期24卷 73-79页

作者：刘伟柳爱利周绍磊 department of Control Engineering Naval Aeronautical and Astronautical University

This paper studies the distributed H∞control problem of identical linear time invariant multi-agent systems subject to external disturbances. A directed graph containing a spanning tree is used to model the communication topology. Based on the relative states of the neighbor agents and a subset of absolute states of the agents, distributed static H∞controllers are proposed. The concept of an H∞performance region is extended to the directed graph situation. Then the results are used to solve the leader–follower H∞consensus problem. Sufficient conditions are proposed based on bounded real lemma and algebraic graph theory. The effectiveness of the theoretical results is illustrated via numerical simulations.

关键词： multi-agent systems H∞ control performance region leader–follower H∞ consensus

Atomistic simulations of the tensile and melting behavior of silicon nanowires

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Journal of Semiconductors 2009年第6期30卷 20-24页

作者：荆宇航孟庆元赵伟 department of astronautical Science and Mechanics Harbin Institute of Technology

Molecular dynamics simulations with Stillinger-Weber potential are used to study the tensile and melting behavior of single-crystalline silicon nanowires（SiNWs）.The tensile tests show that the tensile behavior of the SiNWs is strongly dependent on the simulation temperature,the strain rate,and the diameter of the *** a given diameter,the critical load significantly decreases as the temperature increases and also as the strain rate ***,the critical load increases as the diameter ***,the melting tests demonstrate that both melting temperature and melting heat of the SiNWs decrease with decreasing diameter and length,due to the increase in surface *** melting process of SiNWs with increasing temperature is also investigated.

关键词： Si nanowires molecular dynamics tensile behavior melting behavior

Combined forecast method of HMM and LS-SVM about electronic equipment state based on MAGA

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Journal of Systems Engineering and Electronics 2016年第3期27卷 730-738页

作者： Jianzhong Zhao Jianqiu Deng Wen Ye Xiaofeng Lü department of Ordnance Science and Technology Naval Aeronautical and Astronautical University

For the deficiency that the traditional single forecast methods could not forecast electronic equipment states, a combined forecast method based on the hidden Markov model（HMM） and least square support vector machine（LS-SVM） is presented. The multi-agent genetic algorithm（MAGA） is used to estimate parameters of HMM to overcome the problem that the Baum-Welch algorithm is easy to fall into local optimal solution. The state condition probability is introduced into the HMM modeling process to reduce the effect of uncertain factors. MAGA is used to estimate parameters of LS-SVM. Moreover, pruning algorithms are used to estimate parameters to get the sparse approximation of LS-SVM so as to increase the ranging performance. On the basis of these, the combined forecast model of electronic equipment states is established. The example results show the superiority of the combined forecast model in terms of forecast precision,calculation speed and stability.

关键词： parameter estimation hidden Markov model(HMM) least square support vector machine(LS-SVM) multi-agent genetic algorithm(MAGA) state forecast

CT local reconstruction of solid rocket motor based on PI-POCS-TVM

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航空动力学报 2017年第2期32卷 470-476页

作者： LU Hong-yi CHEN Qing-gui ZHU Min LI Peng ZHAO Ru-yan WANG Bin Airborne Vehicle Engineering department Naval Aeronautical and Astronautical University Yantai Shandong 264001 China Qingdao Branch Naval Aeronautical and Astronautical University Qingdao Shandong 266041 China No. 7 department Naval Aeronautical and Astronautical University Yantai Shanctong 264001 China

In order to test the defects of solid rocket motor(SRM)accurately and efficiently,the computed tomography(CT)inspection scheme for SRM's defects was investigated and a CT local reconstruction algorithm called prior information-projection onto convex sets-total variation minimization(PI-POCS-TVM)was *** SRM was first inspected by industrial CT(ICT)to generate a low-resolution SRM image used as the prior information,then high-resolution local inspection was carried out for SRM's *** validate the effectiveness of the CT inspection scheme for SRM's defects,one SRM was inspected by a narrow fan beam ICT *** back projection(FBP)algorithm,POCS,POCS-TVM and PI-POCS-TVM algorithms were applied to reconstruct CT *** performance of these algorithms was also *** demonstrated the effectiveness of the CT inspection scheme for SRM's ***,the PI-POCS-TVM algorithm has better local reconstruction image quality than the other three algorithms,showing great significance for accurate measurement of SRM's defects.

关键词： interior tomography exterior tomography compressed sensing prior information projection onto convex sets-total variation minimization(POCS-TVM) solid rocket motor