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Improved bias proportional navigation with multiple constraints for guide ammunition

第32届中国控制与决策会议

作者： Ziqi Wang Qingei Hu Tuo Han Kewei Zhong School of Automation Science and Electrical Engineering Beihang University Beijing Advanced Innovation Center for Big-Data Based Precision Medicine Beihang University Shanghai Aerospace Control Technology Institute

In this paper,a guidance law considering impact angle constraint for missiles with time-varying velocity is proposed via geometric methods.The guidance concept is based on the geometric property of the circle involute.A simple path planning approach is proposed to find the desired involute trajectory that connects the missile and target while satisfying the impact angle constraint.Once the desired involute trajectory is determined,the reference line-of-sight（LOS） profiles with respect to the downrange are obtained consequently.Then,a robust guidance law is constructed to achieve the precise tracking of the reference LOS profiles that finally guides missiles with time-varying velocity to meet the impact angle constraint.Nonlinear simulations under various scenarios are conducted to validate the proposed guidance law.

关键词： Guidance Law Path Planning impact angle Geometric Methods

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Journal of Systems Engineering and Electronics 2017年第6期28卷 1193-1202页

作者： Wei Pang Xiaofang Xie Tao Sun Department of Ordnance Science and Technology Naval Aeronautical and Astronautical University Yantai 264001 China

According to the infrared guidance ammunition(GA)attacking non-maneuvering targets on the ground or sea level,an improved bias proportional navigation(IBPN) is put forward,which can meet the constraints of the impact angle and the angle of attack(AOA). The motion equations and the collision triangle for the GA and the target are established in the two-dimensional plane. In accordance with the collision triangle, the integral value of the bias term is solved and BPN is designed on the basis of the relative velocity. To ensure the new method can be solved, closedloop equation of the IBPN is deduced. Considering the limitation of the AOA and the seeker angle, a four-phase IBPN is improved by setting different phases of the bias term. At the same time, the guidance law will make the impact angle achieve the desired angle and the normal acceleration also converges to zero. The simulation results show that the improved guidance law can be applied to various flight tasks and has great potential for engineering applications.

关键词： improved proportional navigation impact angle bias term look angle normal acceleration

Three-dimensional adaptive finite-time guidance law for intercepting maneuvering targets

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Chinese Journal of Aeronautics 2017年第6期30卷 1985-2003页

作者： Yujie SI Shenmin SONG Center for Control Theory and Guidance Technology Harbin Institute of Technology Harbin 150001 China

To intercept maneuvering targets at desired impact angles, a three-dimensional terminal guidance problem is investigated in this study. Because of a short terminal guidance time, a finitetime impact angle control guidance law is developed using the fast nonsingular terminal sliding mode control theory. However, the guidance law requires the upper bound of lumped uncertainty including target acceleration, which may not be accurately obtained. Therefore, by adopting a novel reaching law, an adaptive sliding mode guidance law is provided to release the drawback. At the same time, this method can accelerate the convergence rate and weaken the chattering phenomenon to a certain extent. In addition, another novel adaptive guidance law is also derived; this ensures systems asymptotic and finite-time stability without the knowledge of perturbations bounds.Numerical simulations have demonstrated that all the three guidance laws have effective performances and outperform the traditional terminal guidance laws.

关键词： Adaptive control Finite-time guidance law impact angle Sliding mode control Three-dimensional guidance law

Optical flow based guidance system design for semi-strapdown image homing guided missiles

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Chinese Journal of Aeronautics 2016年第5期29卷 1345-1354页

作者： Huang Lan Song Jianmei Zhang Minqiang Cai Gaohua Key Laboratory of Dynamics and Control of Flight Vehicle Ministry of Education School of Aerospace Engineering Beijing Institute of Technology Beijing 100081 China Beijing Aerospace Automatic Control Institute Beijing 100854 China

This paper focuses mainly on semi-strapdown image homing guided （SSIHG） system design based on optical flow for a six-degree-of-freedom （6-DOF） axial-symmetric skid-to-turn missile. Three optical flow algorithms suitable for large displacements are introduced and compared. The influence of different displacements on computational accuracy of the three algorithms is analyzed statistically. The total optical flow of the SSIHG missile is obtained using the Scale Invariant Feature Transform （SIFT） algorithm, which is the best among the three for large displacements. After removing the rotational optical flow caused by rotation of the gimbal and missile body from the total optical flow, the remaining translational optical flow is smoothed via Kalman filtering. The circular navigation guidance （CNG） law with impact angle constraint is then obtained utilizing the smoothed translational optical flow and position of the target image. Simulations are carried out under both disturbed and undisturbed conditions, and results indicate the proposed guidance strategy for SSIHG missiles can result in a precise target hit with a desired impact angle without the need for the time-to-go parameter.

关键词： Guidance strategy impact angle Optical flow Scale Invariant Feature Transform （SIFT） Semi-strapdown image homing guided （SSIHG） missile

Trajectory shaping guidance law based on virtual angle with terminal constraints

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Journal of Systems Engineering and Electronics 2013年第6期24卷 992-1002页

作者： Xijing Hu Xuemei Huang Beijing Institute of Control and Electronic Technology Science and Technology on Information Systems Engineering Laboratory

A trajectory shaping guidance law based on virtua angle （TSGLBVA） is proposed for a re-entry vehicle with the constraints of terminal impact angles and their time derivatives. In the view of differential properties of the maneuvering trajectory, a virtual angle and a virtual radius are defined. Also, the shaping trajectory of the vehicle is established by the polynomials of the virtual angle. Then, four optimized parameters are selected according to the theorem of parameters transformation presented in this paper. Finally, a convergent variant of the Nelder-Mead algorithm is adopted to obtain the reference trajectory, and a trajectory feedback tracking guidance law is designed. The simulation results demonstrate that the TSGLBVA ensures the re-entry vehicle to impact a target precisely from a specified direction with smal terminal load factor command, as well as to obtain a maximum or constrained terminal velocity according to various requirements.

关键词： re-entry guidance law trajectory shaping virtual angle terminal constraint impact angle

Erosion Resistance of CaO-Al_2O_3-SiO_2 System Glass-Ceramics

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Journal of Wuhan University of Technology(Materials Science) 2004年第3期19卷 51-53页

作者：何峰 Wuhan University of Technology

The erosion resistance tests were used to research the erosion wear behavior of CaO-Al-2O-3-SiO-2 system glass-ceramic. With the orthogonal test method, the factors that affect the erosion wear of CaO-Al-2O-3-SiO-2 system glass-ceramic such as particles property, impact angle, impact time, size of particles were discussed.The results show that erosion rate rises along a straight line at the early period of erosion wear.With the impact time increased,the erosion rate deviates from original staight line,tendency of the erosion rate increases.With the size of paricle increased,it will have more kinetic energy,the erosion rate of the surface of glass-ceramics ploate rises.

关键词： glass-ceramic erosion resistance impact angle

Nonlinear FEM Analysis of Dropped Risers in Offshore Platform Operations

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Nonlinear FEM Analysis of Dropped Risers in Offshore Platfor...