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General design principle of artillery for firing accuracy

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Defence Technology（防务技术） 2022年第12期18卷 2125-2140页

作者： linfang qian Guangsong Chen Minghao Tong Jinsong Tang School of Mechanical Engineering Nanjing University of Science and TechnologyNanjing210094China

In this paper,based on the topological description method,the kinematic and dynamic equations of the projectile flight and projectile-artillery coupling system during the whole process of firing are *** factors that can affect the projectile burst points,namely the state parameters of the projectile on the muzzle and state parameters of the barrel muzzle,as well as the factors that affect the barrel muzzle state parameters,are *** this basis,the design principle of artillery firing accuracy is *** error analysis and the corresponding inverse problem,the extraction method of key parameters affecting artillery implicated motion,the conformal and control method of rotating band are analyzed and ***,the presented method is verified through a vehicle mounted howitzer case,and the muzzle state parameter interval is obtained meeting the given firing *** addition,the sensitivity analysis of artillery parameters shows that the less the correlation between the parameters and the barrel,the less the influence on the projectile implicated *** analysis of the coupling effect between rifling and the rotating band shows that the uniform rifling is the optimal form for the conformal of the rotating band during firing.

关键词： Firing accuracy Projectile-artillery coupling Rotating band conformal Sensitivity analysis Error control

Production of Ammonium Lactate by Fed-batch Fermentation of Rhizopus oryzaefrom Corncob Hydrolysate

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Chemical Research in Chinese Universities 2004年第4期20卷 403-406页

作者： BAIDong-mei LIShi-zhong linfang-qian SchoolofChemicalEngineering＆Technology TianjinUniversityTianjin300072P.R.China DepartmentofEngineeringScience UniversityofOxfordOxfordOX13PJUK

L-(+)-Lactic acid production from corncob hydrolysate as a cheap carbohydrate source by fed-batch fermentation of Rhizopus oryzaeHZS6 was studied. After 96 h of fermentation in a 5 L fermentor, the final concentration of ammonium L-(+)-lactate, average productivity(based on initial xylose concentration) and maximum dry cell weight were 132.4 g/L, 1.38 g/(L·h), and 8.9 g/L respectively. The optical purity of L-(+)-lactate was 98.8%.

关键词： Corncob hydrolysate Ammonium lactate Rhizopus oryzae Fed-batch fermentation

Numerical Study of Parachute-Payload Land Site Distribution with Randomize Wind Gust Model

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Transactions of Nanjing University of Aeronautics and Astronautics 2018年第2期35卷 383-394页

作者： Tang Jianhua qian linfang Yin qiang Jiang Li School of Mechanical Engineering Wuyi UniversityJiangmen 529020 P. R. China School of Mechanical Engineering Nanjing University of Science and Technology Nanjing 210094 P.R. China

A parachute-payload model with randomize wind gust is developed to study the landing accuracy of the parachute decelerator system,which can be exactly described by the landing site *** research focuses on the steady descent phase of the parachute descent process,so the parachute and the payload suspension formulation during the phase are mainly *** addition,since the wind effects have a significant impact on the land site distribution of the passive decelerator system and it is difficult to obtain the exact wind profile in practice,major features of parachute-payload system are studied via the randomized wind gust *** the randomized wind gust formulation is adopted,the wind effect can be considered without the exact wind gust profile and the parachute aerodynamic simulation can be fulfilled with ***,the model is validated and discussed,and the parachute land site distributions with different wind randomize profiles are presented for *** results show that when parachute is less stable,the land site tends to have a larger variance.

关键词： parachute decelerator system wind profile Monte Carlo land site distribution

Numerical integration of rotation with geometry propagators

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International Journal of Modeling, Simulation, and Scientific Computing 2016年第3期7卷 150-170页

作者： Jianhua Tang linfang qian qiang Yin School of Mechanical Engineering Nanjing University of Science and Technology Nanjing P.R.China

Commutator free method is an effective method for solving rotating *** examples show that the use of the proposed combining method can achieve the same order accuracy with less computation than other geometry integration ***,it is difficult to be directly applied to mechanic dynamics *** this paper,commutator free method which is often applied to rotation integration and classical Runge–Kutta(RK)method which is usually operated in Linear space are combined to solve the multi-body dynamic *** explicit Runge–Kutta coefficients are reconstructed to meet different order accuracy integration *** reconstruction method is discussed and coefficients are *** this method,the dynamic equations can be solved accurately and economically without much modification on the classical numerical ***,CG method and CF method can also be combined with adaptive RK method without many ***,the results of the examples show that with less computation,fourth-order combining method is as accurate as fourth-order Crouch–Grossman algorithm.

关键词： Runge-Kutta method geometry propagators commutator free method

High-dimensional uncertainty quantification of projectile motion in the barrel of a truck-mounted howitzer based on probability density evolution method

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Defence Technology（防务技术） 2024年第2期32卷 209-221页

作者： Mingming Wang linfang qian Guangsong Chen Tong Lin Junfei Shi Shijie Zhou Nanjing University of Science and Technology Nanjing 210094JiangsuChina Northwest Institute of Mechanical and Electrical Engineering Xianyang 712099ShaanxiChina Nanjing Vocational University of Industry Technology Nanjing 210023JiangsuChina

This paper proposed an efficient research method for high-dimensional uncertainty quantification of projectile motion in the barrel of a truck-mounted ***,the dynamic model of projectile motion is established considering the flexible deformation of the barrel and the interaction between the projectile and the ***,the accuracy of the dynamic model is verified based on the external ballistic projectile attitude test ***,the probability density evolution method(PDEM)is developed to high-dimensional uncertainty quantification of projectile *** engineering example highlights the results of the proposed method are consistent with the results obtained by the Monte Carlo Simulation(MCS).Finally,the influence of parameter uncertainty on the projectile disturbance at muzzle under different working conditions is *** results show that the disturbance of the pitch angular,pitch angular velocity and pitch angular of velocity decreases with the increase of launching angle,and the random parameter ranges of both the projectile and coupling model have similar influence on the disturbance of projectile angular motion at muzzle.

关键词： Truck-mounted howitzer Projectile motion Uncertainty quantification Probability density evolution method

Uncertainty quantification of mechanism motion based on coupled mechanism—motor dynamic model for ammunition delivery system

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Defence Technology（防务技术） 2024年第3期33卷 125-133页

作者： Jinsong Tang linfang qian Longmiao Chen Guangsong Chen Mingming Wang Guangzu Zhou Nanjing University of Science and Technology Nanjing 210094China Northwest Institute of Mechanical and Electrical Engineering Xianyang 712099China

In this paper,a dynamic modeling method of motor driven electromechanical system is presented,and the uncertainty quantification of mechanism motion is investigated based on this *** main contribution is to propose a novel mechanism-motor coupling dynamic modeling method,in which the relationship between mechanism motion and motor rotation is established according to the geometric coordination of the *** advantages of this include establishing intuitive coupling between the mechanism and motor,facilitating the discussion for the influence of both mechanical and electrical parameters on the mechanism,and enabling dynamic simulation with controller to take the randomness of the electric load into *** simulation considering feedback control of ammunition delivery system is carried out,and the feasibility of the model is verified *** on probability density evolution theory,we comprehensively discuss the effects of system parameters on mechanism motion from the perspective of uncertainty *** work can not only provide guidance for engineering design of ammunition delivery mechanism,but also provide theoretical support for modeling and uncertainty quantification research of mechatronics system.

关键词： Ammunition delivery system Electromechanical coupling dynamics Uncertainty quantification Generalized probability density evolution

A novel multi-resolution network for the open-circuit faults diagnosis of automatic ramming drive system

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Defence Technology（防务技术） 2024年第4期34卷 225-237页

作者： Liuxuan Wei linfang qian Manyi Wang Minghao Tong Yilin Jiang Ming Li School of Mechanical Engineering Nanjing University of Science and TechnologyNanjing 210094JiangsuChina Northwest Institute of Mechanical and Electrical Engineering Xianyang 712099China

The open-circuit fault is one of the most common faults of the automatic ramming drive system(ARDS),and it can be categorized into the open-phase faults of Permanent Magnet Synchronous Motor(PMSM)and the open-circuit faults of Voltage Source Inverter(VSI). The stator current serves as a common indicator for detecting open-circuit faults. Due to the identical changes of the stator current between the open-phase faults in the PMSM and failures of double switches within the same leg of the VSI, this paper utilizes the zero-sequence voltage component as an additional diagnostic criterion to differentiate *** the variable conditions and substantial noise of the ARDS, a novel Multi-resolution Network(Mr Net) is proposed, which can extract multi-resolution perceptual information and enhance robustness to the noise. Meanwhile, a feature weighted layer is introduced to allocate higher weights to characteristics situated near the feature frequency. Both simulation and experiment results validate that the proposed fault diagnosis method can diagnose 25 types of open-circuit faults and achieve more than98.28% diagnostic accuracy. In addition, the experiment results also demonstrate that Mr Net has the capability of diagnosing the fault types accurately under the interference of noise signals(Laplace noise and Gaussian noise).

关键词： Fault diagnosis Deep learning Multi-scale convolution Open-circuit Convolutional neural network

Research on simulation of gun muzzle flow field empowered by artificial intelligence

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Defence Technology（防务技术） 2024年第2期32卷 196-208页

作者： Mengdi Zhou linfang qian Congyong Cao Guangsong Chen Jin Kong Ming-hao Tong School of Mechanical Engineering Nanjing University of Science and TechnologyNanjing210094China Northwest Institute of Mechanical and Electrical Engineering Xianyang712099ShaanxiChina School of Automation Nanjing University of Science and TechnologyNanjing210094China

Artificial intelligence technology is introduced into the simulation of muzzle flow field to improve its simulation efficiency in this paper.A data-physical fusion driven framework is ***,the known flow field data is used to initialize the model parameters,so that the parameters to be trained are close to the optimal *** physical prior knowledge is introduced into the training process so that the prediction results not only meet the known flow field information but also meet the physical conservation *** two examples,it is proved that the model under the fusion driven framework can solve the strongly nonlinear flow field problems,and has stronger generalization and *** proposed model is used to solve a muzzle flow field,and the safety clearance behind the barrel side is *** is pointed out that the shape of the safety clearance under different launch speeds is roughly the same,and the pressure disturbance in the area within 9.2 m behind the muzzle section exceeds the safety threshold,which is a dangerous *** with the CFD results shows that the calculation efficiency of the proposed model is greatly improved under the condition of the same calculation *** proposed model can quickly and accurately simulate the muzzle flow field under various launch conditions.

关键词： Muzzle flow field Artificial intelligence Deep learning Data-physical fusion driven Shock wave

Adaptive Sliding-Mode Tracking Control for an Uncertain Nonlinear SISO Servo System with a Disturbance Observer

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Journal of Shanghai Jiaotong university(Science) 2018年第3期23卷 376-383页

作者： YUE Caicheng CHEN Hongbina qian linfang KONG Jianshoub a. School of Mechanical Engineerin b. School of Automation Nanjing University of Science and Technology Nanjing 210094 China

An adaptive sliding mode controller with a disturbance observer （ASMC-DO） is proposed for the control of a single-input and single-output （SISO） servo system which has uncertain parameters, nonlinear friction, disturbance and input saturation. It is difficult to choose the suitable value of the parameters. The newly designed adaptive method is used to reduce the effects of system time-varying parameters, such as the moment of inertia and the damp coefficient. The robustness of object is improved. A DO is selected to approximate the compound disturbance and to render the estimate error convergent in finite time. The stability and the convergence of the closed-loop system are proved by using the Lyapunov theory. Experimental results show that the proposed ASMC-DO can better satisfy the influence of variable parameters and external disturbance to the control precision of the SISO servo system than other two controllers. The effectiveness of the proposed controller is showed. The control input stability and robust performances of is reduced. the input saturation system are enhanced and the chattering

关键词： adaptive sliding mode controller disturbance observer input saturation uncertain nonlinear SISO servo system