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Tu H.,Northeastern University China | Tu H.,Ordnance Science and Research Academy of China | Lou W.,Beijing Institute of Technology | Sun Z.,Northeastern University China | And 2 more authors.
Advances in Engineering Software | Year: 2017

Based on the deterministic performance analysis of latching mechanism in MEMS (micro-electro-mechanical system)-based Safety and Arming device (S&A device), probabilistic algorithms and Kriging approximation method coupling with finite element simulation are used to quantify the effect of input uncertainties on the response metrics of the mechanism. It firstly uses performance function to represent the failure of the latching mechanism mathematically, and then constructs the corresponding reliability model according to structural reliability theory. In order to relieve the burden of further reliability and sensitivity calculations, Kriging interpolation technique is adopted to approximate the performance function and hence simplify the reliability model. Samples of input variables and the corresponding response, which all together serve as the inputs of Kriging approximation, are gotten through finite element simulations based on the design of experiments. An efficient CAE software integration method is proposed to facilitate the repetitive FE-based calculations of those samples. Finally, FORM (First Order Second Moment Method) is utilized to get the reliability index and its sensitivities with respect to the input random variables and their parameters, which can not only be employed for reliability assessment of the latching mechanism, but also can help to identify key factors for additional structural improvements. © 2017 Elsevier Ltd


Zhang X.-P.,China North Vehicle Research Institute | Wang Y.-L.,Ordnance Science and Research Academy of China | Du M.-G.,China North Vehicle Research Institute | Yang Y.,China North Vehicle Research Institute
Binggong Xuebao/Acta Armamentarii | Year: 2016

The life and reliability of integrated transmission device may be significantly affected by the vibration, harshness and quality of the device. The relationship between the internal excitation and vibration of the device is one of the important research works. An experimental scheme is presented to obtain the relationship between the internal excitation and vibrations of an integrated transmission device. A coupling signal analysis method is also proposed to investigate the signals from the multiple measurement points and experimental conditions. The relationship between the internal excitation and vibration of the device is obtained based on the proposed experimental method, which can provide some guidance for the structure optimization of the device. The results show that the experimental analysis method can be used to not only determine the vibration source location of the integrated transmission device, but also find the dominant frequency which should be controled, which can provide some guidance for the structure optimization of the device. © 2016, Editorial Board of Acta Armamentarii. All right reserved.


Li G.P.,Beijing Institute of Technology | Shen L.H.,Beijing Institute of Technology | Zheng B.M.,Ordnance Science and Research Academy of China | Xia M.,Beijing Institute of Technology | Luo Y.J.,Beijing Institute of Technology
Advanced Materials Research | Year: 2014

AP-based nano-limit growth energetic materials(NLGEM) were prepared by using SiO2 gel as nano-limit growth skeleton materials and using sol-gel method combining solution crystallization to make AP recrystallized in the nanopores of SiO2 gel skeleton to form AP/SiO2 NLGEM. The chemical and physical structure and properties of AP/SiO2 NLGEM were studied in detail. AP with nanoscale particles size range from 69nm to108nm was recrystallized in the pore of SiO2 gel skeleton and the particle size of AP increased with the amount of AP in NLGEM increasing. Moreover, the preparation method didn't change the crystal form of AP and bring impurities to NLGEM. The decomposition of AP/SiO2 NLGEM was a one-step process, which was indicated its decomposition was more concentrate than pure AP and AP/SiO2 simple physical mixture (AP/SiO2 SPM), whose decomposition was a two-step process. At the time, the decomposition heat of AP/SiO2 NLGEM was higher than that of pure AP and AP/SiO2 SPM. The sensitivity of AP/SiO2 NLGEM was lower than those of the pure energetic components and physical mixtures according to the impact sensitivity test. © (2014) Trans Tech Publications, Switzerland.


Liu J.-H.,Beijing Institute of Technology | Shan J.-Y.,Beijing Institute of Technology | Zhao X.,Ordnance Science and Research Academy of China
Binggong Xuebao/Acta Armamentarii | Year: 2014

Disturbance torque directly affects the tracking and measuring accuracies of seeker and the guidance precision. To analyze the degradation of gyro-stabilized seeker tracking accuracy due to disturbance torque, the dynamics models of seeker, seeker gimbal friction and seeker cable disturbance torques are established. To reduce the influence of disturbance torque on seeker tracking accuracy, a practical disturbance observer (DOB) is designed to compensate the disturbance torques. Multi-rate sampling problem due to the difference between sampling and hold times of seeker system and DOB is considered. A discrete DOB design method is proposed based on Nyquist stability theory, so the conservation of small gain design method can be removed. Sampling, hold and filter time constants of DOB are specified by balancing system stability, disturbance torque compensation and sensor noise reduction. An extracting method of information which is required by DOB is proposed by integrating the measurement information of missile and seeker. The mathematical simulation results show that the designed DOB can improve the seeker tracking accuracy efficiently.


Gao X.-X.,Nanjing University of Science and Technology | Su Z.-Z.,Ordnance Science and Research Academy of China | Sun H.-G.,Institute of Armament Technology | Hou B.-L.,Nanjing University of Science and Technology
Binggong Xuebao/Acta Armamentarii | Year: 2014

An optimization design method is proposed to indirectly improve the reliability of positioning precision for shell transfer arm in ammunition automatic loading system with uncertain parameters. The main uncertain factors that influence the positioning performance are analyzed. Space is transformed, and Latin hypercube sampling is applied for the uncertain variables. The error weights are calculated according to the distances from sampling points to the mean point in the transformed space. An electromechanical model is established with MATLAB/Simulink, and the simulations are run for every sampling point to get the positioning errors. The weighted sum of these errors is calculated as a performance index. This performance index is optimized using particle swarm algorithm. This method has remarkable optimization effect and good computational efficiency.


Wen Q.-Q.,Beijing Institute of Technology | Liu D.-W.,Ordnance Science and Research Academy of China | Xia Q.-L.,Beijing Institute of Technology | Li R.,Beijing Institute of Technology
Binggong Xuebao/Acta Armamentarii | Year: 2014

An extended optimal guidance law with terminal miss distance and impact angle constrains is derived. The guidance law is obtained as the solution of a linear quadratic optimal control problem with the goal function weighted by a power of the time-to-go. Based on the analytical expression for the change of guidance command with time and the adjoint system analysis method, the command characteristics and dimensionless miss distance of guidance law are analyzed. The result shows that the acceleration command of guidance law can be converged into zero in the final time of guidance, which may create a good situation for terminal angle of attack control. A design principle for selection of guidance law gain is discussed. Finally, according to the requirements of engineering application, the methods on calculating the guidance initial condition and maximal required acceleration are given. The effectiveness and practicality of the guidance law are demonstrated through simulation.


Zhang W.-Y.,Beijing Institute of Technology | Xia Q.-L.,Beijing Institute of Technology | Liu D.-W.,Ordnance Science and Research Academy of China
Binggong Xuebao/Acta Armamentarii | Year: 2015

A guidance law with multiple constraints (GLMC) is derived in light of the effect of disturbance rejection rate of seeker on the stability and guidance accuracy of the multi-constraint guidance system, and a multi-constraint guidance model is established, in which the disturbance rejection rate of seeker is considered. The effect of disturbance rejection rate and guidance parameters on the stability of guidance system is analyzed. In addition, the adjoint function is employed to analyze the guidance performance variations of the multi-constraint guidance law with or without the influence of disturbance rejection rate of seeker. The results indicate that any decrease in guidance time constant or flight remaining time as well as increase in the disturbance rejection rate will lead to a decrease in the stability of guidance system. The GLMC can sustain a disturbance rejection rate of about 1%. In the practical applications, it is essential to control the level of disturbance rejection rate of seeker strictly and reduce the effect of parasitical loop on the stability of guidance system so that a superior guidance performance of the multi-constraint guidance law can be ensured. © 2015, China Ordnance Society. All right reserved.


Zhang D.-C.,Beijing Institute of Technology | Sun J.,Ordnance Science and Research Academy of China | Wen Q.-Q.,Beijing Institute of Technology | Xia Q.-L.,Beijing Institute of Technology
Beijing Ligong Daxue Xuebao/Transaction of Beijing Institute of Technology | Year: 2016

A guidance method was proposed, considering seeker field of view constraints and impact angle constraint, for the reason that the seeker look angle of air to ground weapon may overstep the field of view and lose the target when it follows the optimal trajectory shaping guidance law to achieve large impact angle. An analytic expression of seeker look angle was deduced based on the assumption of linearization model and small angle. The factors that influence seeker look angle and the range of maximum seeker look angle were analyzed. On this basis, the guidance method satisfied the seeker field of view constraints through changing the initial line of sight angle or relaxed impact angle constraints was put forward for different air to ground weapons. The select principle of initial line of sight value and the maximum impact angle calculation method were also presented. Numerical simulations verified the effectiveness of the seeker look angle theoretical expressions and the proposed guidance method. © 2016, Beijing Institute of Technology. All right reserved.


Zhao B.,Beijing Institute of Technology | Zhang M.-D.,Beijing Institute of Technology | Ju D.-M.,Ordnance Science and Research Academy of China
Binggong Xuebao/Acta Armamentarii | Year: 2015

A dynamics model for the navigating pose of amphibious vehicle in water is established. The dynamic mesh technology and the hybrid coupled algorithm are used to study the change rule of navigating pose of amphibious vehicle in sailing, and the navigating pose of amphibious vehicles in still water are discussed. The numerical results are consistent with the experimental results. The result shows that the vehicle undergoes a sharp motion and a smooth motion during movement before achieving the ultimate navigating pose. After achieving the ultimate navigating pose, the center-of-gravity and the pitch angle slightly change. During the process of sailing from drainage state to coasting state, the body center of gravity gradually increases; the dynamic buoyancy to support the vehicle weight increases, and the static buoyancy decreases. ©, 2015, China Ordnance Society. All right reserved.


Qi Y.,Beijing Jiaotong University | Chang Q.-Y.,Beijing Jiaotong University | Wang B.,Beijing Jiaotong University | Li J.,Ordnance Science and Research Academy of China
Binggong Xuebao/Acta Armamentarii | Year: 2015

Surface of specimen is textured with a LM-YLP-20F-II laser marking machine to develop regularly arranged micro-dimples. Ring-block line contact friction tests are performed to study the influence of laser textures' area density on friction and wear behaviors under dry sliding. The morphologies of textures are examined with a stylus profiler and a scanning electron microscope. A simplified finite element contact model of friction pair with surface textures is developed to simulate sliding friction, and the stress distribution is obtained to analyze the effects of surface textures on tribological properties. The results show that the effect of laser surface texturing on the surface hardness of specimen is remarkable. Both the wear losses of two mating specimens are reduced compared with non-textured specimens when the area density of laser surface textures is less than 20%, and the wear rate of textured specimen still goes down. However the wear rate of the mating specimen goes up when the area density of laser surface textures is over 20%. High stress location and magnitude shift with the change in the dimples on contact surfaces, which is beneficial to wear resistance. ©, 2015, China Ordnance Society. All right reserved.

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