By determining the state variables of a fuze safety system,some mathematical models——the system of ordinary differential and functional differential equations about the system's arming process are founded in a s...By determining the state variables of a fuze safety system,some mathematical models——the system of ordinary differential and functional differential equations about the system's arming process are founded in a state space.Also,the arming states and restricted relations of the safety factors are described and some demonstrations are presented.展开更多
A Bayesian method is used to evaluate the component safety failure model parameter of the safe arming system of an air faced missile in flight. It was proved that Bayes estimation of the model parameter is coinciden...A Bayesian method is used to evaluate the component safety failure model parameter of the safe arming system of an air faced missile in flight. It was proved that Bayes estimation of the model parameter is coincident with the physical explanation of the prior probability density distribution of the random parameter.展开更多
As an essential component of ammunition, pyrotechnics can control ignition with high reliability.However, due to limits of fabrication technology, traditional pyrotechnics are bulky. To achieve both functionality and ...As an essential component of ammunition, pyrotechnics can control ignition with high reliability.However, due to limits of fabrication technology, traditional pyrotechnics are bulky. To achieve both functionality and miniaturization, MEMS pyrotechnics integrate initiator, safety-and-arming(S&A) device and lead charge and keep all components within a small size. MEMS S&A devices, as the core component to ensure system safety, are difficult to achieve active and rapid response to control signals with high safety and reliability. In order to overcome the difficulty, we propose the design and characterization of a MEMS pyrotechnic with a double-layer barrier S&A device. The MEMS pyrotechnic is a high-integrated device with an overall size of 13.4 × 8.5 × 5.2 mm^(3). The initiator is a Ni Cr bridge foil covered with an Al/Cu O energetic film, which can generate flame when ignited by an excitation voltage.To match the flame energy, lead styphnate is chosen in this study as the lead charge. The S&A device contains four semi-circular barriers, which are directly driven by V-shape electro-thermal actuators to gain active control of the pyrotechnics’ ignition condition with rapid response. To improve the system’s reliability, the four barriers are axisymmetrically placed in two layers, two barriers for each layer, to constitute a double-layer structure with a thickness of 100 μm. The ignition test results show that the S&A device can prevent the initiator from detonating the lead charge in safety condition. In arming condition, the lead charge will be detonated.展开更多
The delay arming process of initiating explosive （ IE ） brakes for fuse is complex and hard to be verified. A numerical simulation model of IE brakes was established based on the arbitrary La- grange-Euler method. T...The delay arming process of initiating explosive （ IE ） brakes for fuse is complex and hard to be verified. A numerical simulation model of IE brakes was established based on the arbitrary La- grange-Euler method. The model included the structure, the air filed, etc. The simulation boundary conditions were defined, including the contacts, blasting parameters of the explosive and the fluid- solid coupling interface. The simulation results show that the shear pin of the chosen IE can be cut off. When the piston needs to move 0.8 cm, the time set to the delay arming of the IE brakes model is about 40μS. The maximum displacement of the piston is 1. 17 cm. The model provides basis for parameters design and further improvement of IE brakes.展开更多
文摘By determining the state variables of a fuze safety system,some mathematical models——the system of ordinary differential and functional differential equations about the system's arming process are founded in a state space.Also,the arming states and restricted relations of the safety factors are described and some demonstrations are presented.
文摘A Bayesian method is used to evaluate the component safety failure model parameter of the safe arming system of an air faced missile in flight. It was proved that Bayes estimation of the model parameter is coincident with the physical explanation of the prior probability density distribution of the random parameter.
基金the National Key R&D Program of China(2017YFB1102900)the Fundamental Research Funds for the Central Universities(xzy012019004).
文摘As an essential component of ammunition, pyrotechnics can control ignition with high reliability.However, due to limits of fabrication technology, traditional pyrotechnics are bulky. To achieve both functionality and miniaturization, MEMS pyrotechnics integrate initiator, safety-and-arming(S&A) device and lead charge and keep all components within a small size. MEMS S&A devices, as the core component to ensure system safety, are difficult to achieve active and rapid response to control signals with high safety and reliability. In order to overcome the difficulty, we propose the design and characterization of a MEMS pyrotechnic with a double-layer barrier S&A device. The MEMS pyrotechnic is a high-integrated device with an overall size of 13.4 × 8.5 × 5.2 mm^(3). The initiator is a Ni Cr bridge foil covered with an Al/Cu O energetic film, which can generate flame when ignited by an excitation voltage.To match the flame energy, lead styphnate is chosen in this study as the lead charge. The S&A device contains four semi-circular barriers, which are directly driven by V-shape electro-thermal actuators to gain active control of the pyrotechnics’ ignition condition with rapid response. To improve the system’s reliability, the four barriers are axisymmetrically placed in two layers, two barriers for each layer, to constitute a double-layer structure with a thickness of 100 μm. The ignition test results show that the S&A device can prevent the initiator from detonating the lead charge in safety condition. In arming condition, the lead charge will be detonated.
基金Supported by the National Natural Science Foundation of China(11372047)
文摘The delay arming process of initiating explosive （ IE ） brakes for fuse is complex and hard to be verified. A numerical simulation model of IE brakes was established based on the arbitrary La- grange-Euler method. The model included the structure, the air filed, etc. The simulation boundary conditions were defined, including the contacts, blasting parameters of the explosive and the fluid- solid coupling interface. The simulation results show that the shear pin of the chosen IE can be cut off. When the piston needs to move 0.8 cm, the time set to the delay arming of the IE brakes model is about 40μS. The maximum displacement of the piston is 1. 17 cm. The model provides basis for parameters design and further improvement of IE brakes.
