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以高冲击、高速环境下的某口径火炮反后坐装置为研究对象,讨论了后坐阻力对火炮静止性和射击稳定性的影响,研究了磁流变阻尼器对火炮后坐运动的控制作用。设计了火炮磁流变后坐阻尼器及冲击试验平台;考虑冲击载荷激励下惯性力的影响,建立了火炮反后坐装置动力学模型并进行了计算仿真,对所设计长行程磁流变阻尼器进行了冲击试验,测试其在冲击载荷下的动态特性,并进行了后坐过程半实物仿真控制。试验结果表明设计的长行程火炮用磁流变阻尼器可有效抑制冲击载荷激励作用,为进一步实现火炮后坐力与行程控制的一体化设计和工程应用奠定了基础。 相似文献
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为获取最优的后坐阻力规律FR(t)以提高射击稳定性,基于多体系统动力学建模理论,建立了全炮动力学模型;以火炮射击时跳动量最小为目标,节制杆各圆锥段直径为设计变量,基于优化设计方法对优化问题进行了求解。优化结果表明:最大后坐阻力和火炮跳高都小于优化前,后坐阻力曲线更加平缓,火炮射击稳定性得到明显改善。 相似文献
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重力对火炮动力偶臂测量与计算影响研究 总被引:1,自引:0,他引:1
动力偶臂是影响火炮射击稳定性和射击精度的关键参数.采用结构有限元方法建立了重力载荷作用下的火炮后坐部分变形计算模型,得到了不同射角条件下火炮后坐部分重力载荷作用变形结果,给出了重力对火炮后坐部分动力偶臂的影响规律,分析了火炮后坐部分方向质量偏心不影响其动力偶臂测量结果的原因,指出了专用夹具实验测试方法没有反映重力效应引起的身管弯曲使后坐部分质心变化的不足,提出了重力对火炮动力偶臂影响的修正方法,传统的专用夹具实验测试结果必须经过修正才能得到精确值. 相似文献
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火炮磁流变阻尼器工作在高速高冲击条件下,其动力特性及其力学模型与常用的磁流变阻尼器存在较大不同。针对某型号火炮设计了反后坐用磁流变阻尼器,并进行了5种不同电流下的动态测试,验证了该阻尼器对反后坐控制的可行性。由试验分析得,火炮磁流变阻尼器的输出力不仅与控制电流和后坐速度有关,还与高冲击条件下的磁流变效应的复杂性、惯性力、腔体内气体压力等因素有关。提出了用改进的多项式模型描述火炮磁流变阻尼器,该模型具有形式简洁,易于求解逆模型,便于实时控制等优点。通过参数辨识后的模型能较好的描述火炮反后坐过程中阻尼器的输出力。 相似文献
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基于永磁式电涡流阻尼技术对火炮反后坐装置的制退机结构进行了全新的设计,通过原理试验验证了同极相对永磁阵列方案具有良好的缓冲制动性能。建立永磁式电涡流制退机仿真模型,针对强冲击载荷下的火炮后坐过程分析制退机在不同磁轭、气隙、导体筒以及导磁筒厚度参数影响下的后坐阻力特性。建立多目标后坐阻力优化模型,并基于BP(back propagation)神经网络和遗传算法下的现代优化计算方法,在Pareto解集中寻找改善去磁效应影响下后坐阻力曲线马鞍形特征的最优解。研究结果表明:电涡流阻尼器冲击响应试验验证了磁路方案的可行性和仿真结果的正确性;磁轭与导体筒厚度这两项电涡流制退机参数对后坐阻力和去磁程度影响较大;优化后的后坐阻力曲线马鞍形特征减弱,曲线充满度从79.51%提高到88.05%,验证优化策略可行。 相似文献
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针对枪炮冲击型MR阻尼器的特点,以某单管25mm火炮为研究对象,基于Herschel-Bulkley本构模型,建立了该25mm火炮磁流变后坐阻尼器的轴对称一维层流模型。同时运用ANSYS软件,建立了该阻尼器MR阀的电磁有限元模型,求得了环状流口间MR流体的磁通密度。将MR流体流动模型和MR阀有限元结果相结合,求得了不同MR流体行为指数和不同磁场作用下阻尼力随活塞速度的变化规律。建立了火炮后坐运动方程,评价了MR流体行为指数对后坐阻尼器性能的影响。 相似文献
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A. J. N. Batista A. M. P. Rodrigues J. Basí lio Sim es C. M. B. A. Correia J. Sousa C. A. F. Varandas 《Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment》1996,370(2-3):484-489
This paper describes a fully programmable, VME based, eight channel, arbitrary waveform generator, specially adequate for the control of operation of high temporal resolution diagnostics of nuclear physics experiments. Each channel is built around an 1 Mega-sample-per-second, 12 bit, digital-to-analog converter and it is provided with 8 kWords of FIFO memory allowing operation in a free running mode. The main operational features of this module are described. Methods for assessing its performance are discussed and the test results are presented. Application of this multiple waveform generator on the operation of two diagnostics of the tokamak ISTTOK is referred. 相似文献
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In this contribution the problem of maximizing the efficiency of a hybrid power unit at a specified output power level by optimizing the generator current trajectory as well as the design variables that can be chosen during the machine design process is investigated. The concept is demonstrated based on a hybrid single-cylinder diesel engine that is coupled to an electric generator. By developing a model of the system and using open-loop optimal control the optimal operating strategy and the optimal machine design are determined. Besides that, the problems occurring in the application of this strategy to a test rig are discussed. For this purpose, a model-free real-time optimization concept based on extremum seeking control is presented. The effectiveness of both the model-based and the model-free concept are demonstrated by simulation and experimental results. 相似文献
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《Science, Measurement & Technology, IET》2008,2(6):485-492
An investigation to reduce harmonic content in the air-gap flux density of a high-temperature superconducting synchronous generator with a coreless rotor is reported. Three-dimensional finite-element field simulation has been used to predict the voltage waveform of the machine. A simple technique was applied to guide the design process. This allowed the waveform to be improved using a small number of finite-element models. 相似文献
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为设计出符合消费者感性需求的产品,提出基于支持向量机的产品感性意象值预测方法。先确定产品的感性意象、造型设计要素以及感性评价矩阵。在此基础上,以造型设计要素为自变量,以感性意象评价值为因变量,利用LIBSVM软件,通过对惩罚函数、不敏感损失函数以及核函数等相关参数的分析设置,建立产品感性意象值的预测模型。结合办公座椅进行研究,结果表明支持向量机具有较高的预测精度,所提出的方法是正确可行的。 相似文献
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目的探索人本化包装设计的本质内涵及评价方法,为客观评价和提高产品包装的人本化设计水平提供理论支持和实现方法。方法运用文献研读、理论提炼和逻辑推演等方法,提炼出人本化包装设计的评价指标体系,在此基础上,引入支持向量机,构建了人本化包装设计的量化评价模型。结果验证了支持向量机评价模型的可行性和有效性。结论该评价模型具有广泛的应用前景,为提升产品包装的人本化设计水平提供了理论依据。 相似文献
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针对现有烫印设备存在自动化水平低和人机界面交互性差的问题,采用三维参数化设计方法对全自动烫印机的结构进行设计,以三菱新一代FX3GE系列PLC (programmable logic controller,可编程逻辑控制器)和T5L智能触摸屏为核心搭建了全自动烫印机的网络化控制系统,实现了伺服电机与气缸的高速、高精度驱动,PID (proportion integration differentiation,比例积分微分)温度控制以及多参数人机数据交互。针对传统固定路径顺序指令编程模式无法满足小批量定制化生产模式的要求的问题,提出了基于有限状态机(finite state machine, FEM)模型的全自动烫印机控制程序设计方法。首先,对全自动烫印工艺和运动工位的分布、数量和逻辑顺序关系进行功能规划与模块化设计,建立了层次化有限状态机模型;然后,根据状态迁移事件与状态转换条件构造了烫印动作的状态转换图;最后,结合图论思想,将状态转换图映射到邻接链表变量空间,并采用变量配置方式驱动邻接链表,从而完成对状态转换图的遍历和拓扑扩展。仿真结果表明,与传统的指令编程模式相比,基于有限状态机模型的全自动烫印机控制程序设计方法不仅提升了开发效率和组态化编程水平,有效降低了控制程序的维护成本,还保证了伺服电机与气缸的时序动作不会干涉和交叉,提高了控制系统的可靠性,具有广阔的工程应用前景。 相似文献
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Hale P.D. Dienstfrey A. Wang J. Williams D.F. Lewandowski A. Keenan D.A. Clement T.S. 《IEEE transactions on instrumentation and measurement》2009,58(10):3554-3568
We describe a method for calibrating the voltage that a step-like pulse generator produces at a load at every time point in the measured waveform. The calibration includes an equivalent-circuit model of the generator that can be used to determine how the generator behaves when it is connected to arbitrary loads. The generator is calibrated with an equivalent-time sampling oscilloscope and is traceable to fundamental physics via the electro-optic sampling system at the National Institute of Standards and Technology. The calibration includes a covariance-based uncertainty analysis that provides the uncertainty at each time in the waveform vector and the correlations between the uncertainties at the different times. From the calibrated waveform vector and its covariance matrix, we calculate pulse parameters and their uncertainties. We compare our method with a more traditional parameter-based uncertainty analysis. 相似文献
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《IEEE transactions on instrumentation and measurement》1983,32(3):398-403
The purpose of this paper is to describe the design and characteristics of an arbitrary waveform generator, built at the Biophysical and Electronic Engineering Division of the Electrical Engineering Department of the University of Genoa, which exhibits the following features: a) The signal waveform is any band-limited periodic signal, whose frequency content ranges from 0.125 mHz up to 30 MHz. The low-frequency limit has been chosen in order to meet the needs of bioengineering, mechanical, and chemical applications. The high-frequency limit covers, for instance, TV and image processing applications. b) The noise level is at least 66 dB below the maximum signal level. c) Typical distortion is less than -66 dB. d) The generator's performance can be easily improved, depending on the availability of up-to-date solid-state devices, without changing its design. 相似文献