Design And Research On The Key Technologies For Small Electro-mechanical Fuze

In the current situation of modern wars, especially where the terrorist activities are rampant, it has become the emphasis of many nations to research on small-caliber air-burst ammunition, which is perfect for city wars and street wars; To a small-caliber air-burst ammunition, the special type small electro-mechanical fuze is the brain that determines the location and damage power of the explosion. The realization of the smart design of special type small electro-mechanical fuze can improve the combating performance of small-caliber weaponry system greatly.Smart designing of special type small electro-mechanical fuze means the fuze that is miniaturized and intelligentized. This essay conducts systematic researches into smart designing of the special type fuze in the application background of a small-caliber weapon adopting air-burst ammunition. The researches include those on:small-caliber air burst fuze design, MEMS fuze technology, technology of electromagnetic inductive power supplying and information setting field in bore, and hardware and software design of fuze circuit.For the demands, design requirements, and technical difficulties of small-caliber ammunition fuze, this essay analyzes on the four aspects of fuze in detail:small safe and arming(S&A) device, the action principle of aerial bombardment, programmable setting method and fuze power. Basing on the analyses, a small-caliber grenade fuze design framework is constructed and its key technologies are proposed.The safe and arming device is an indispensable part of fuze. The technology of fuze-downsizing, which focuses on the MEMS safe and arming device, is discussed in this essay. Two kinds of MEMS safe and arming devices and theirs parts are analyzed and designed, such as components of energy storage, zigzag setback time delay device, and electromagnetic drive mechanism. Furthermore, with the help of national synchronic radiation laboratory, the micro fabrication technique of the MEMS safe and arming device is in the process on the basis of researches on MEMS fabrication technique.Inductive setting technology is the core of the realization of fuze smart designing. In this essay, the technology of electromagnetic inductive setting and inductive power supplying in bore is adopted to construct the small-caliber induction fuze. Equipped with this technology, on one hand, battlefield information can be promptly delivered into fuze to realize the programmable function; on the other hand, electromagnetic energy can be restored for the fuze working in the whole trajectory. Which saves additional power source equipment, and realizs the fuze-downsizing still further.The realization of electromagnetic inductive power supplying and information setting field in bore, in essence, is the energy transfer through the medium of alternate electromagnetic field. And because of that, eddy current is generated in the metal barrel, reducing efficiency of energy transfer. Electromagnetic penetration equation is deduced from Maxwell's basic equations of electromagnetic field. Analysis on the diffusion process of the electromagnetic field of small caliber metal launch barrel wall from electromagnetic field time domain and frequency domain respectively leads to the result that:the magnetic field frequency of excitation coil must be less than 2.5kHz to guarantee the internal magnetic field strength of about 80% of the external. The higher the frequency rises, the faster the penetration attenuates. Also, the calculation of eddy current's wasted power in small caliber metal launch barrel wall is discussed from the current solving model.The circuit system of small-caliber air burst fuze is the core of special type small electro-mechanical fuze, who's features, design requirements, module composing as well as module selecting and design ideas are analyzed in this essay. About low-power consumption design, its significance is discussed and a fuze circuit power model is constructed to analyze the influence factors from aspects of static power and dynamic power; about EMC (electromagnetic compatibility) design, its design methods are discussed from the aspects of hardware and software.A prototype model of special type small electro-mechanical is designed from aspects of hardware, software, low power consumption and EMC of the circuit. The outcomes of both static and dynamic experiments indicate that the special type small electro-mechanical fuze meet the performing requirements. This system realizes the inductive energy supplying and data setting within 1 s with the 100% accuracy, and the restored energy meets the requirement of providing power to work no less than 8s for the fuze in the whole trajectory.