无人飞艇平台摄像机防振研究

无人飞艇作为理想的信息平台,在预警、反恐、侦察监视和通信等方面发挥着重要作用。而艇载侦察监视设备CCD摄像机受到飞艇发动机振动的影响,会对成像产生消极影响。为此,分析了影响飞艇摄像机的成像质量的因素,采用被动减振的方案,达到了有效克服振动的目的。     

Multi-objectives nonlinear structure optimization for actuator in trajectory correction fuze subject to high impact loadings

This paper presents an actuator used for the trajectory correction fuze, which is subject to high impact loadings during launch. A simulation method is carried out to obtain the peak-peak stress value of each component, from which the ball bearings are possible failures according to the results. Subsequently, three schemes against impact loadings, full-element deep groove ball bearing and integrated raceway, needle roller thrust bearing assembly, and gaskets are utilized for redesigning the actuator to effectively reduce the bearings' stress. However, multi-objectives optimization still needs to be conducted for the gaskets to decrease the stress value further to the yield stress. Four gasket's structure parameters and three bearings' peak-peak stress are served as the four optimization variables and three objectives, respectively. Optimized Latin hypercube design is used for generating sample points, and Kriging model selected according to estimation result can establish the relationship between the variables and objec-tives, representing the simulation which is time-consuming. Accordingly, two optimization algorithms work out the Pareto solutions, from which the best solutions are selected, and verified by the simulation to determine the gaskets optimized structure parameters. It can be concluded that the simulation and optimization method based on these components is effective and efficient.     

Multi-objective design optimization of composite submerged cylindrical pressure hull for minimum buoyancy and maximum buckling load capacity

This paper presents the design optimization of composite submersible cylindrical pressure hull subjected to 3 MPa hydrostatic pressure. The design optimization study is conducted for cross-ply layups [0s/90t/0u], [0s/90t/0u]s, [0s/90t]s and [90s/0t]s considering three uni-directional composites, i.e. Carbon/Epoxy, Glass/Epoxy, and Boron/Epoxy. The optimization study is performed by coupling a Multi-Objective Genetic Algorithm (MOGA) and Analytical Analysis. Minimizing the buoyancy factor and maximizing the buckling load factor are considered as the objectives of the optimization study. The objectives of the optimization are achieved under constraints on the Tsai-Wu, Tsai-Hill and Maximum Stress composite failure criteria and on buckling load factor. To verify the optimization approach, optimization of one particular layup configuration is also conducted in ANSYS with the same objectives and constraints.     

无线电引信超宽带电磁脉冲效应研究

利用超宽带(UWB)电磁脉冲发生器对不同姿态的某型无线电引信进行了超宽带电磁脉冲辐照实验研究。实验表明:电点火头本身在UWB辐照下是安全的,当超宽带电磁脉冲峰峰值场强达到106 kV/m时,在引信加电工作情况下可以使实验引信全部引爆;此外,引信-弹体自身等效天线长度增加会导致无线电引信超宽带电磁脉冲效应更加明显。     

某压力容器壳体水压爆裂原因分析

针对某压力容器壳体生产过程中出现的水压试验异常爆裂问题,通过材料成分、热处理组织、力学性能、宏观和微观断口分析,确定了裂源位置、裂纹缺陷性质、产生原因及断裂机理;通过断裂力学分析,确定了水压爆裂的原因。提出了淬火工艺改进建议和防范措施。     

基于MSP430单片机的海浪水压场自动测量系统

提出了基于MSP430单片机的水压场自动测量系统的设计方案和实现方法并进行了实际测量.解决了自动测量系统中的低噪声、低功耗、高分辨率、大容量存储等关键技术.实验结果表明:该系统具有自动运行、电池供电、记录时间长等特点.适于高海况条件下的海浪水压场的测量.     

高精度气压源的Fuzzy-PID控制研究

设计了Fuzzy-PID双模控制器并应用到高精度气源压力控制系统中.试验表明,单纯采用PID控制的高精度气源压力控制系统具有精度高的优点,但不适应系统参数的变化.Fuzzy-PID双模控制器具有响应速度快、稳态误差小、鲁棒性强的优点.通过试验比较了传统PID、Fuzzy控制和Fuzzy-PID双模控制3种控制策略,试验结果表明,Fuzzy-PID双模控制器综合了Fuzzy控制和PID控制的优点,适用于高精度气源压力控制系统.     

弹引系统膛内纵向过载测试与仿真

设计了弹丸膛内纵向过载直接测试系统,加工特制弹丸及假引信体,保证其质量、外形、长度与原弹丸及相应的引信体保持一致,保证其与原弹丸及相应引信膛内运动过程相同.采用弹载存储测试技术,将加速度传感器安装在弹丸内部,然后采用软回收技术回收弹体,取出弹载测试存储模块,将弹载测试存储模块通讯串口与微机串口相连,并将弹载存储器存储的数据导入计算机并分析处理,获取弹丸膛内纵向过载动态分布规律.并数值仿真了引信膛内纵向过载,仿真结果与试验结果吻合较好,为引信安全性问题的研究提供了可靠的数据支持,同时也说明了理论仿真的正确性和试验方法的可靠性.     

Theoretical study of an energetic material di-1H-1,3,4-triazole derivatives

Computations by density functional theory (DFT) method are performed on a series of di-1H-1,3,4-triazole derivatives with different substituents and linkages. The heat of formation (HOF) is predicted by the designed isodesmic reactions. The predicted results reveal that –N₃ and –NN– groups are effective structural units for increasing the HOF values of the di-1H-1,3,4-triazole derivatives. The HOMO–LUMO gap is affected by the substituents and linkage groups. Detonation performance is evaluated using the Kamlet–Jacobs approach based on the calculated density and HOF. The results indicate that –NO₂, –NF₂, –NH–, –NH–NH– and –NN– groups are helpful for enhancing the detonation properties of di-1H-1,3,4-triazole derivatives. The bond dissociation energy and bond order of the weakest bonds are analyzed to investigate their stability. It is observed that the –CH₂–, –CH₂–CH₂– and –CHCH– groups are effective structural units for improving the stabilities of these derivatives. Considering the detonation performance and the stability, five compounds are screened as the potential candidates for high energy density materials.     

管道机器人在三通处的通过性分析

三通是管道机器人经常遇到的典型障碍之一,克服该障碍的能力用管道机器人在三通处通过性来描述。文中提出一种描述差压驱动式管道机器人三通通过性的数学模型,该模型由一组组合约束构成。通过对约束方程的分析讨论、与管道机器人弯道通过性的对比分析,得出了规律性的结论。管道机器人在三通处的姿态、单元体的几何尺寸、行走轮结构形式对其通过性都有不同程度的影响。所提出数学模型是管道机器人三通自主行走控制策略设计和相应结构设计的理论基础。