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An intelligent control method based on artificial neural network for numerical flight simulation of the basic finner projectile with pitching maneuver

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Defence Technology（防务技术） 2024年第2期32卷 663-674页

作者： Yiming Liang Guangning Li Min Xu Junmin Zhao Feng Hao Hongbo Shi northwestern Polytechnical University School of Astronautics Xi’an 710072China china north industries group corporation no 203 research institute Xi’an 710065China

In this paper,an intelligent control method applying on numerical virtual flight is *** proposed algorithm is verified and evaluated by combining with the case of the basic finner projectile model and shows a good application ***,a numerical virtual flight simulation model based on overlapping dynamic mesh technology is *** order to verify the accuracy of the dynamic grid technology and the calculation of unsteady flow,a numerical simulation of the basic finner projectile without control is carried *** simulation results are in good agreement with the experiment data which shows that the algorithm used in this paper can also be used in the design and evaluation of the intelligent controller in the numerical virtual flight ***,combined with the real-time control requirements of aerodynamic,attitude and displacement parameters of the projectile during the flight process,the numerical simulations of the basic finner projectile’s pitch channel are carried out under the traditional PID(Proportional-Integral-Derivative)control strategy and the intelligent PID control strategy *** intelligent PID controller based on BP(Back Propagation)neural network can realize online learning and self-optimization of control parameters according to the acquired real-time flight *** with the traditional PID controller,the concerned control variable overshoot,rise time,transition time and steady state error and other performance indicators have been greatly improved,and the higher the learning efficiency or the inertia coefficient,the faster the system,the larger the overshoot,and the smaller the stability *** intelligent control method applying on numerical virtual flight is capable of solving the complicated unsteady motion and flow with the intelligent PID control strategy and has a strong promotion to engineering application.

关键词： Numerical virtual flight Intelligent control BP neural network PID Moving chimera grid

Effects of carbon content on the microstructure and tensile properties of a low-density steel

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International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 391-401页

作者： Yongxuan Shang Mingyu Fan Shuyong Jiang Zhongwu Zhang Key Laboratory of Superlight Materials and Surface Technology Ministry of EducationCollege of Materials Science and Chemical EngineeringHarbin Engineering UniversityHarbin 150001China State Key Laboratory of Metal Material for Marine Equipment and Application Iron&Steel Research Institute of Ansteel Group CorporationAnshan 114009China

Carbon can change the phase components of low-density steels and influence the mechanical *** this study,a new method to control the carbon content and avoid the formation ofδ-ferrite by decarburization treatment was *** microstructural changes and mechanical characteristics with carbon content induced by decarburization were systematically ***-Jaoul(C-J)analysis was employed to examine the work hardening characteristics during the tensile *** decarburization by heat treatments,the carbon content within the austenite phase decreased,while Mn and Al were almost unchanged;this made the steel with full austenite transform into the austenite and ferrite dual ***,(Ti,V)C carbides existed in both matrix phase and the mole fraction almost the *** addition,the formation of other carbides *** loss induced a decrease in strength due to the weakening of the carbon solid *** the steel with the single austinite,the deformation mode of austenite was the dislocation planar glide,resulting in the formation of *** the dual-phase steel,the deformation occurred by the dislocation planar glide of austenite first,with the increase in strain,the cross slip of ferrite took place,forming dislocation cells in *** the late stage of deformation,the work hardening of austinite increased rapidly,while that of ferrite increased slightly.

关键词： low-density steels carbon content decarburization strengthening mechanisms work hardening behavior

Extended optimal guidance law with impact angle and acceleration constriants

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Journal of Systems Engineering and Electronics 2014年第5期25卷 868-876页

作者： Ran Li Qunli Xia Qiuqiu Wen Department of Aerospace Beijing Institute of Technology china north industries group corporation

The extended optima straints of miss distance and Schwartz inequality. To reduce guidance law with terminal conmpact angle is derived by the terminal acceleration and eliminate gravity disturbance absolutely, the object function, which designs the weight of control command to be the power function of time-to-go＇s reciprocal, is given. And the gravity is considered when building the state equation. Based on the parsing express of the guidance command change with varying time and adjoint system analysis method, the command characteristics and the non-dimensional miss distance of the guidance law are analyzed, a design principle of guidance order coefficients is discussed. Finally, based on the requirement of engineering, the method to calculate the guidance condition and maximal required acceleration of the guidance law is given. The simulation demonstrates that not only the guidance law can satisfy the terminal position and impact angle constraints, but also the terminal acceleration can be converged toward zero, which will support a good situation for the terminal angle of attacking control.

关键词： impact angle constraint optimal guidance law accel- eration command guidance order.

Optimal guidance of extended trajectory shaping

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Chinese Journal of Aeronautics 2014年第5期27卷 1259-1272页

作者： Wang Hui Lin Defu Cheng Zhenxuan Wang Jiang School of Aerospace and Engineering Beijing Institute of Technology china north industries group corporation

To control missile＇s miss distance as well as terminal impact angle, by involving the timeto-go-nth power in the cost function, an extended optimal guidance law against a constant maneuvering target or a stationary target is proposed using the linear quadratic optimal control *** extended trajectory shaping guidance（ETSG） law is then proposed under the assumption that the missile-target relative velocity is constant and the line of sight angle is small. For a lag-free ETSG system, closed-form solutions for the missile＇s acceleration command are derived by the method of Schwartz inequality and linear simulations are performed to verify the closed-form results. Normalized adjoint systems for miss distance and terminal impact angle error are presented independently for stationary targets and constant maneuvering targets, respectively. Detailed discussions about the terminal misses and impact angle errors induced by terminal impact angle constraint, initial heading error, seeker zero position errors and target maneuvering, are performed.

关键词： Extended trajectory shaping Impact angle error Miss distance Missile Optimal guidance Terminal constraint

Time-to-go weighted optimal trajectory shaping guidance law

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Journal of Beijing institute of Technology 2011年第3期20卷 317-323页

作者：王辉林德福程振轩 School of Aerospace Engineering Beijing Institute of Technology china north industries group corporation

For maneuvering target, the optimal trajectory shaping guidance law which can simultaneously achieve the designed specifications on miss distance and final impact angle was deduced using optimal control theory based on the time-to-go weighted function. Based on the same cost function, the closed-form solutions of the guidance law were derived when the initial displacement of missile, final impact angle, heading error and target maneuver was introduced into the lag-free guidance system. To validate the closed-form solutions, the simulation of the lag-free system was done and the simulation results exactly matched the closed-form solutions and only when the exponent is greater than zero, the final acceleration approaches to zero.

关键词： trajectory shaping guidance optimal control time-to-go close-form solution

Extended trajectory shaping guidance law considering a first-order autopilot lag

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Journal of Beijing institute of Technology 2015年第3期24卷 291-297页

作者：王辉王江程振轩 School of Aerospace Engineering Beijing Institute of Technology china north industries group corporation

To satisfy the terminal position and impact angel constraints,an optimal guidance problem was discussed for homing missiles. For a stationary or a slowly moving target on the ground,an extended trajectory shaping guidance lawconsidering a first-order autopilot lag（ ETSG L-C FAL） was proposed. To derive the ETSG L-C FAL,a time-to-go- nth power weighted objection function was adopted and three different derivation methods were demonstrated while the Schwartz inequality method was mainly *** performance of the ETSG L-C FAL and the ETSG L guidance laws was compared through *** results showthat although a first-order autopilot is introduced into the ETSG L-C FAL guidance system,the position miss distance and terminal impact angle error induced by the impact angle is zero for different guidance time.

关键词： extended trajectory shaping guidance law time-to-go first-order autopilot guidance performance

Event-Triggered Consensus for Discrete-Time Multi-agent Systems with Parameter Uncertainties Based on a Predictive Control Scheme

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Journal of Systems Science & Complexity 2020年第3期33卷 706-724页

作者： LIU Xiaoyu XUAN Yongbo ZHANG Zhongyu DIAO Zhaoshi MU Zhenxing LI Zhitao china north industries group corporation Limited china Ordnance Industry Navigation and Control Technology institute Beijing 100821China Beijing Aeronuatical Technology research Center Beijing 100076China

In this paper,the event-triggered consensus for linear discrete-time multi-agent systems with parameter uncertainties is *** parameter uncertainty is assumed to be *** event-triggered consensus protocol based on the predictive control method is proposed to make the multi-agent system achieve *** for the design of the consensus protocol,the problem of estimating the control input is transformed into the problem of estimating state differences between ***,the event-triggered consensus protocol proposed in this paper only demands each agent to mornitor its state to determine its event-triggered instants.A sufficient existence condition for the consensus protocol is proposed based on the linear matrix *** a sufficient condition for the nonexistence of the Zeno-like behaviour is also ***,a numerical example is given to illustrate that the event-triggered consensus protocol proposed in this paper can make the multi-agent system with parameter uncertainties achieve consensus effectively.

关键词： Consensus event-triggered strategy multi-agent systems predictive scheme

A high-efficient triboelectric-electromagnetic hybrid nanogenerator for vibration energy harvesting and wireless monitoring

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Science china(Information Sciences) 2022年第4期65卷 229-237页

作者： Jian HE Xueming FAN Dongyang ZHAO Min CUI Bing HAN Xiaojuan HOU Xiujian CHOU Science and Technology on Electronic Test and Measurement Laboratory North University of China College of Mechatronic Engineering North University of China Beijing institute of Computer Application China North Industries Group Corporation Limited

Scavenging mechanical vibration energy by combining triboelectric nanogenerators(TENGs) and electromagnetic generators(EMGs) is a renewable and low-carbon way to generate electric power. In this paper, we fabricate a cylindrical structure hybrid nanogenerator based on spring structure to effectively scavenge vibration energy. The introduction of spring structure not only enhances the space utilization, but also supports the moving magnet. Owing to its innovative structure, the instantaneous output power of TENG and EMG are 0.88 mW at a load of 10 MΩ and 216.7 mW at a load of 60 Ω, respectively. With the aids of a power management circuit, the hybrid nanogenerator can provide continuous power for two hygrothermographs connected in series. In addition, a self-powered wireless acceleration sensing monitoring system(SWAM) is developed to measure the acceleration signals of vibration sources. This study provides a novel guideline for harvesting mechanical vibration energy.

关键词： mechanical vibration energy spring structure triboelectric electromagnetic wireless monitoring system

3D direct writing and micro detonation of CL-20 based explosive ink containing O/W emulsion binder

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Defence Technology（防务技术） 2022年第8期18卷 1340-1348页

作者： Zhan-xiong Xie Chong-wei An Bao-yun Ye Jia-qing Mu Chun-yan Li Min-jie Li Song-jin Liu School of Environment and Safety Engineering North University of ChinaTaiyuanShanxi030051China Shanxi Engineering Technology research Center for Ultrafine Powder North University of China030051TaiyuanChina No.55 Research Institute of China North Industries Group CorporationChangchun130012China

The booming development of DIW technology present an unprecedented prospect in energetic materials field and has attracted great interest due to its relative simplicity and high flexibility of ***,a novel CL-20 based explosive ink formulation have been developed successfully for MEMS initiation systems via DIW *** designed PVA/GAP into an oil-in-water(O/W)emulsion,in the way that the aqueous solution of PVA as water phase,the ethyl acetate solution of GAP as oil phase,the combination of Tween 80 and SDS as emulsifier,BPS as a curing agent of *** ideal formulation with good shear-thinning rheology properties and clear gel point was prepared using only 10 wt%*** dual-cured network formed during the curing process made the printed sample have good mechanical *** printed samples had satisfactory molding effect without cracks or fractures,the crystal form of CL-20 not changed and the thermal stability have *** of explosive inks via DIW in micro-scale grooves had excellent detonation performances,which critical detonation size was 1×0.045 mm,detonation velocity was 7129 m/s and when the corner reaching 150°can still detonated *** study may open new avenues for developing binder systems in explosive ink formulations.

关键词： Direct writing Explosive ink Emulsion binder system CL-20 based energetic composites Micron detonation