In order to meet the needs of microelectronic devices for EMP protection, a MEMS electromagnetic energy sparing mechanism based on the principle of microcorona discharge and MEMS process is proposed to provide a design solution for electromagnetic pulse protection of microelectronic devices. The MEMS electromagnetic energy channeling mechanism is small in size, with a fast response time and low cost, and it is the first choice of microelectronic devices for EMP protection. Based on the MEMS process, the fabrication process and response principle of the MEMS electromagnetic energy-sparing mechanism are introduced. After the design is completed, the MEMS electromagnetic energy channeling mechanism with different electrode parameters is simulated and analyzed. The simulation results show that the electrode width of 50μm produces a larger electric field strength under the same trigger voltage. The experimental results show that the electrode width of 30μm has more significant ablation effect after breakdown.

With the demand for high-safety, high-integration, and lightweight micro- and nano-electronic components, an MEMS electromagnetic energy-releasing component was innovatively designed based on the corona discharge theory. The device subverted the traditional device-level protection method for electromagnetic energy, realizing the innovation of adding a complex circuit system to the integrated chip through micro-nanometer processing technology and enhancing the chip’s size from the centimeter level to the micron level. In this paper, the working performance of the MEMS electromagnetic energy-releasing component was verified through a combination of a simulation, a static experiment, and a dynamic test, and a characterization test of the tested MEMS electromagnetic energy-releasing component was carried out to thoroughly analyze the effect of the MEMS electromagnetic energy-releasing component. The results showed that after the strong electromagnetic pulse injection, the pulse breakdown voltage of the MEMS electromagnetic energy-releasing component increased exponentially in terms of the pulse injection voltage, and the residual pulse current decreased significantly from one-third to one-half of the original, representing a significant protective effect. In a DC environment, the breakdown voltage of the needle–needle structure of the MEMS electromagnetic energy-releasing component was 144 V, and the on-time was about 0.5 ms.

Double ceramic layer thermal barrier coatings (DLC-TBCs) are favored for combining the benefits of top and bottom ceramic materials. The thickness ratio of the top and bottom ceramic layers significantly impacts the performance of the DLC-TBCs. In the design process, it is generally desired to balance its thermal insulation properties with a long service life. Therefore, this study establishes a multi-objective parameter optimization design method based on NSGA-II to optimize the thickness of the CeYSZ/Al2O3 DCL-TBCs. Experimental verification of the coating performance was conducted based on the optimization results. Firstly, based on theoretical and numerical models, a quantitative analysis was conducted on the effects of the thickness of each material in the CeYSZ/Al2O3 DCL-TBCs system on thermal insulation and thermal stress. Space parameters were obtained using optimal Latin hypercube sampling, and a radial basis function (RBF) neural network surrogate model was constructed based on the numerical calculation results. Sensitivity analysis was employed to evaluate the impact of the total thickness of the TBCs and the thickness of the Al2O3 ceramic layer on the objective function. Finally, NSGA-II was utilized for optimization. The obtained Pareto optimal solution set was validated, showing that the performance of the CeYSZ 190 μm/Al2O3 120 μm DLC-TBCs satisfied the requirements. Therefore, TBCs of different thicknesses were sprayed and subjected to thermal insulation and thermal shock experiments. The results demonstrated that the optimized TBCs significantly improved service life without compromising thermal insulation, providing a new approach for the subsequent design of DLC-TBCs structures.

Thermal barrier coatings (TBCs) have garnered significant attention as crucial protective components for turbine blades. However, the current use of TBCs is limited by their singular functionality and the inability to accurately obtain the temperature gradient distribution within the coatings. Addressing the aforementioned issues, this paper proposes an intelligent thermal barrier coating embedded with thin-film thermocouples. This method not only provides effective thermal protection but also facilitates the precise measurement of the internal temperature gradient within the coating. To mitigate the thermal mismatch in TBCs under high-temperature environments, which can compromise their lifespan, this study employs multi-objective optimization of structural parameters to design an optimal coating thickness. This strategy ensures both superior thermal protection and extended service life. The intelligent temperature-sensing TBCs were fabricated using atmospheric plasma spraying and magnetron sputtering, followed by comprehensive characterization. To validate the performance of the intelligent temperature-sensing TBCs, static tests were conducted in a muffle furnace. The results demonstrated that the sensors exhibit excellent repeatability and high-temperature durability. Furthermore, a test platform replicating the thermal shock conditions of an engine environment was developed. This platform confirmed that the intelligent temperature-sensing TBCs are capable of accurately measuring the internal temperature gradient within the coating under engine-like conditions, offering a novel methodology for engine monitoring and diagnostics.

In aerospace engine applications, high-temperature thin-film strain gauges play a crucial role in the field of material damage state detection and the assessment of the condition of high-temperature turbine blades for aerospace engines. However, several obstacles still exist toward their broad applications, such as low sensitivity, vulnerability to ambient temperature variations, and inaccuracies due to resistance temperature drift. In this work, we introduce an optimized structural strategy to improve the sensitivity of high-temperature thin-film strain gauges. In simulations, structures with varying sensitive grid and cavity sizes were designed, and optimization resulted in improved strain transfer efficiency on the sensitive grid. Subsequently, the strain gauge was fabricated on an aluminum oxide substrate via micro-electromechanical system (MEMS) technology, and the sputtered PdCr thin film was annealed in different gas atmospheres to evaluate their impact on sensor performance. The results indicate that during annealing in an air environment, PdO and Cr2O3 oxides are formed in advance in PdCr. This will adversely affect the performance of the strain gauge, leading to inaccurate measurement results. Furthermore, the sensor demonstrated excellent stability across a wide range of temperature conditions. At room temperature, both single- and pair-cavity designs exhibited high strain sensitivity, with gauge factors of 1.91 and 1.90, respectively. This work presents a strategy for simultaneously improving sensitivity, paving the way for broader applications of high-temperature thin-film strain gauges.

With the increasing application of thin-film sensors in high-temperature applications, there is an escalating demand for insulation layers that provide enhanced resistance to elevated temperatures. However, failure often occurs because of the mismatch in thermal expansion coefficients between the insulation layer and the substrate. This study proposes an underlayer comprising a double ceramic layer of CeYSZ and Al2O3, which preserves the high thermal expansion coefficient and corrosion resistance of CeYSZ while enhancing its electrical insulating properties. The high-temperature electrical insulation performance of underlayers with different ceramic layer structures was experimentally evaluated. The results indicate that the CeYSZ/Al2O3 double ceramic layer exhibits an electrical resistance of 2.1*106 Omega at 800 degrees C and minimal drift after 5 h, demonstrating high stability. Finally, PdCr thin-film strain gauges were fabricated on CeYSZ/Al2O3 double ceramic layer, revealing the stability of the electrical resistance at high temperatures. The porosity of the underlayer cross-sections was also compared, revealing that the double ceramic layer coating effectively fills pores and cracks inherent in singlelayer coatings. This mitigation of conductive pathways reduces the occurrence of such defects, thereby enhancing the high-temperature insulation performance of the underlayer. (c) 2014 xxxxxxxx. Hosting by Elsevier B.V. All rights reserved.

A microelectromechanical systems (MEMS) solid-state logic control chip with three layers—diversion layer, control layer, and substrate layer—is designed to satisfy fuse miniaturization and integration requirements. A mathematical model is established according to the heat conduction equation, and the limit conditions of different structures are presented. The finite element multi-physical field simulation method is used to simulate the size and the action voltage of the diversion layer of the control chip. Based on the surface silicon process, fuse processing, and testing with the MEMS solid-state fuse-logic control chip, a diversion layer constant current, maximum current resistance test, and a control layer of different bridge area sizes, the bridge area size is 200 × 30 μm, and the minimum electrical explosion voltage is 23.6 V. The theoretical calculation results at 20 V and 100 μF demonstrate that the capacitor energy is insufficient to support the complete vaporization of the bridge area, but can be partially vaporized, consistent with the experimental results.

In order to realize that the fuze micro system has both high security and miniaturization characteristics, the spark gap research of Micro-Electro-Mechanical System safety system is carried out. So that to solve the safe and reliable function of the spark gap switch under the low power supply voltage (35 V) of the fuze micro system, the gas gap size and electrode radius are shown to significantly affect the gas breakdown voltage using streamer theory. Based on these results, a spark gap switch with triggering electrodes is designed. The triggering electrode gap is 2 μ m and the main electrode gap is 10 μ m. A spark gap switch test circuit is designed based on the RLC circuit. Through finite element simulation, it is verified that the gas breakdown voltage increases nonlinearly with increasing gap size. Pre-breakdown spark gap switches were fabricated based on the surface silicon process and tested. The test results show that the conduction voltage values of the triggering electrode and the main electrode are basically consistent with the simulation and calculation results. The breakdown voltage of the main electrode can be greatly reduced by applying a certain voltage to the triggering electrode, realize the reliable function in the micro fuze system.

As a result of the unpredictable nature of extreme environments (including temperature, humidity, impact, and other factors), micro-electro-mechanical systems (MEMS) solid-state fuze control modules have an urgent requirement for a MEMS solid-state switch (MEMS-S3). In particular, this switch must remain stable without any energy input after a state transition (i.e., it must be bistable). In this paper, a MEMS bistable solid-state switch (MEMS-bS3) is designed that is based on the concept of producing a micro-explosion. The reliable state switching of the MEMS-bS3 is studied via heat conduction theory and verified via both simulations and experimental methods. The experimental results show that these switches can produce micro-explosions driven by 33 V/47 μF pulse energy. However, the metal film bridge (MFB) structures used in this switch with smaller dimensions (80×20 μm2, 90×30 μm2, and 100×40 μm2) could not enable the switch to realize a reliable state transition, and the state transition rate was less than 40%. When the MFB dimensions reached 120×60 μm2 or 130×70 μm2, the state transition rate exceeded 80%, and the response time was on the μs-scale.

In this paper, in order to make the micro-high explosive train more integrated and reliable, the motion state of flyer driven by two-point initiation copper azide (primary explosive) is studied, and a metal film bridge for two-point ignition is designed. The simulation tests of explosion model and metal bridge model are carried out by AUTODYN and COMSOL respectively. The results show that: 1) the appropriate two-point initiation distance can make the flyer obtain sufficient kinetic energy in a shorter acceleration chamber; 2) the parallel metal bridge structure has more intense temperature rise and higher initiation instantaneity.

为解决传统机电引信在弱环境力条件下无法实现保险解除及传统固态开关无法实现低压驱动(5～35 V)的问题,提出了基于硅基MEMS加工工艺与电晕放电效应的微型引信固态保险设计.结构采用微米尺度设计思想,实现固态保险与引信控制系统能量与信息联通.通过建立电晕放电数学模型,借助COMSOL等有限元分析方法,完成基于低电压驱动的固态保险控制层设计,并结合实验室静态测试实现控制层平均驱动电压(33.1 V)设计.结合电容放电模式与电学与焦耳热仿真,其中,电容储能指标(10 V,10 μF).完成执行层在不同电流强度环境下结构设计.借助MEMS加工工艺,最终实现弱环境力微型引信固态保险设计与制备.

随着MEMS技术的不断发展,对于引信中MEMS安全系统的可靠性提出了更高要求.为了解决目前MEMS安全可靠性分析中存在着各机构可靠度数据不全面,主要依赖于大量实验或专家经验的现状,对MEMS安全系统的失效状况进行分析,构建了MEMS安全系统的故障树,并计算了各重点机构的可靠度功能函数.以此为基础,提出了一种将故障树与贝叶斯网络进行转化的可靠性分析方法.同时针对各失效机理进行了概率重要度和结构重要度计算,从可靠性重要度角度提出了MEMS安全系统设计中的重点优化机构,并进行了计算实例分析.借助于MEMS加工工艺,实现了MEMS安全系统的加工,通过可靠性测试实验,证明了本方法计算的快速准确性.

Abnormal voltages such as electrostatic, constant current, and strong electromagnetic signals can erroneously trigger operation of MEMS pyrotechnics and control systems in a fuze, which may result in casualties. This study designs a solid-state micro-scale switch by combining the corona gas discharge theory of asymmetric electric fields and Peek’s Law. The MEMS switch can be transferred from “off” to “on” through the gas breakdown between the corona electrodes. In the model, one of the two electrodes is spherical and the other flat, so a non-uniform electric field is formed around the electrodes. The theoretical work is as follows. First, the relation among the radius of curvature of the spherical electrode, the discharge gap, and the air breakdown voltage is obtained; to meet the low voltage (30–60 V) required to drive the MEMS switch, the radius of curvature of the spherical electrode needs to be 10–50 μm and the discharge gap between the two electrodes needs to be 9–11 μm. Second, the optimal ratio ε is introduced to parameterize the model. Finally, the corona discharge structural parameters are determined by comparing the theoretical and electric field simulation results. The switch is then fabricated via MEMS processing. A hardware test platform is built and the performing chip tested. It is found that when the electrode gap is 9 μm, the electrostatic voltage is at least 37.3 V, with an error of 2.6% between the actual and theoretical air breakdown voltages. When the electrode gap is 11 μm, the electrostatic voltage is at least 42.3 V, with an error of 10.5% between the actual and theoretical air breakdown voltages. Both cases meet the design requirements.

To solve the problem that the rigid material in the existing MEMS safety-and-arming (S&A) device is prone to fracture and low reliability when facing the instantaneous impact under the detonation, we propose an electrothermal driven MEMS safety-and-arming device based on the flexible material. We combined theoretical analysis and finite element analysis to verify the feasibility of electrothermal driven MEMS safety-and-arming device based on flexible materials. And to make the structure easy to realize, we simplified the assembly process. The simulation results show that the output displacement of the electrothermal actuator increases with the increase of the span length and thickness of the V-beam. The output displacement of the micro displacement amplification mechanism is proportional to the input displacement, which meets the requirements of MEMS safety-and-arming device for the output displacement of the explosion-proof slider. Compared with the nickel slider, the material covered with flexible film can absorb and intercept the detonation energy better.

Traditional silicon-based micro-electro-mechanical system (MEMS) safety and arming devices, such as electro-thermal and electrostatically driven MEMS safety and arming devices, experience problems of high insecurity and require high voltage drive. For the current electromagnetic drive mode, the electromagnetic drive device is too large to be integrated. In order to address this problem, we present a new micro electromagnetically driven MEMS safety and arming device, in which the electromagnetic coil is small in size, with a large electromagnetic force. We firstly designed and calculated the geometric structure of the electromagnetic coil, and analyzed the model using COMSOL multiphysics field simulation software. The resulting error between the theoretical calculation and the simulation of the mechanical and electrical properties of the electromagnetic coil was less than 2% under the same size. We then carried out a parametric simulation of the electromagnetic coil, and combined it with the actual processing capacity to obtain the optimized structure of the electromagnetic coil. Finally, the electromagnetic coil was processed by deep silicon etching and the MEMS casting process. The actual electromagnetic force of the electromagnetic coil was measured on a micro-mechanical test system, compared with the simulation, and the comparison results were analyzed.

This paper studies the guidance and control problem of fixed-wing UAV landing on the ground moving platform. Although many studies should be conducted on the problem of helicopter or quadrotor landing on the mobile platform, but it's always been a challenge of recovering a fixed- wing UAV because of the high speed of UAV and the uncertainty of the motion of the ground moving platform. In this paper, an algorithm of UAV recovery based on differential game method is proposed. With the linear kinematics equation of UAV, the optimal evasion control of ground moving platform is regarded as the worst situation faced by UAV in the process of UAV recovery. The simulation results show that the proposed method can successfully accomplish the UAV recovery task in the worst dynamic environment.

This paper mainly expounds the commonly used UAV recovery methods nowadays and explains the necessity of effective evaluation of the UAV recovery system according to the previous studies; fully considers the influence factors and construct the evaluation system of the UAV recovery system with six evaluation indexes of safety, cost, personnel requirement, landing environment, time as well as UAV's own scale; and determines the influence weight of the UAV recovery system using the analytic hierarchy process. By combining the qualitative and quantitative analysis, the effective evaluation is conducted on the UAV recovery system with the grey relational degree of the recycle system under different indexes calculated with the grey relational analysis. Due to the subjective influence of experts in scoring, the rationality of the evaluation system and the validity of the evaluation results can be verified through controlling the variables, adjusting the weights of different indexes, and painting the line chart, in which the evaluation results change with the indexes, and evaluating all recovery systems at different indexes.

When the missile guidance and control law is implemented in a specific hardware platform, different sampling frequencies occur among the guidance and control components due to the limitation of hardware performance. However, the current missile guidance control law design ignores this problem. This paper comparing the performance of classical control theory and multi-sampling rate control theory in missile platform by testing the response speed and accuracy in serval control channels, simulation results show that the multi-sampling rate control method has obvious advantages over the traditional method.

介绍了当前常用的无人机回收方式,根据已有的研究说明了对无人机回收系统进行有效评估的必要性.充分考虑了当前常用无人机回收系统影响因素,选取了安全性、成本、人员需求、降落环境、时间以及无人机自身条件六个评估指标,构建无人机回收系统评估指标体系,采用层次分析法确定了无人机回收系统的评估指标影响权重.定性与定量相结合,利用灰色关联分析法计算各回收系统在不同指标下的灰色关联度,对无人机回收系统进行有效评估.由于专家打分带有一定的主观因素影响,通过控制变量,改变不同指标的权重,绘制评估结果随指标变化的折线图,针对不同指标进一步评估各回收系统,验证了评估模型的合理性以及评估结果的有效性.