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针对双轴旋转惯导系统转位方案的设计问题,分析旋转式惯导系统自动补偿导航误差的本质,建立旋转式惯导系统误差模型,推导出初始对准状态方程和量测方程,提出16次序和32次序两种转位方案,在两种方案下对陀螺常值漂移引起的导航误差传播特性进行仿真分析,并对两种方案下的初始对准过程进行仿真。研究表明:与16次序转位方案相比,32次序转位方案能更好地补偿陀螺常值漂移引起的导航误差,初始对准过程中对天向陀螺常值漂移的估计精度更高,因此,32次序转位方案优于16次序转位方案。 相似文献
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本文以一台进口仪器的微机改造工作为例,介绍CAT技术在使用典型“小量程传感器”-电感测微头仪器中的应用。其经验在其它同类的轮廓仪,圆度仪和齿轮量仪等中显然也具有普遍意义。 相似文献
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通过高精度测量仪测得的螺纹反馈信息,经数控系统中二分法进行比较,可准确得出螺纹底径(小径),确定起刀点,完成螺纹磨床的自动对刀和磨削余量分析.也可采用三维测头,将三坐标信息反回数控系统实现.并以丝杠和圣维数控系统为例,详细阐述了自动对刀和磨削余量估计的方法.该方法还适用于内外圆磨,平磨. 相似文献
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为提升大直径回转件在旋转状态下的圆度测量精度,在分析3个测点的角度布置对精度影响基础上建立优化模型,提出了基于粒子群及遗传混合算法的三测点角度优化策略。结合外轮廓测量模型及圆度提取技术,分析传感器布置角度对圆度提取精度的影响,建立以误差传递系数为基础的测点位置优化函数;利用粒子群优化与遗传互补产生新粒子种群的混合算法,获取给定谐波级次下三传感器的周向角度值;计算给定谐波级次(160、240、480)下测点的周向布置角度,并对比测点角度优化前后的误差传递系数值,分别用虚拟工件及现场实物完成了测点角度与圆度提取精度的测试实验。结果表明:测点角度优化后的误差传递系数值小于其他布置状态,所提取圆度更接近于其真实圆度值,精度约0.010 mm;该三测点角度优化策略提升了回转件圆度信息的测量精度,为大直径回转件的高精度制作提供了有效检测手段。 相似文献
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邓辉 《兵器材料科学与工程》2017,40(3):21-25
利用脉冲光纤激光对粗粒度青铜金刚石砂轮进行切向整形与径向修锐,并用修整后的砂轮磨削硬质合金工件,对不同磨削阶段的砂轮磨损形式和磨削比、工件表面粗糙度进行研究。结果表明:经激光整形后,砂轮圆跳动和平行度误差分别由83.1、324.6μm下降至6.8、3.8μm;与用碳化硅砂轮修整相比,经激光修整后砂轮表面磨粒的脱落更少、等高性更好、出刃高度更合适;当累计磨削深度达到10、20、30 mm时,砂轮磨损形式为磨粒磨耗和脱落磨损、以磨粒磨耗磨损为主并伴有磨粒脱落和结合剂磨耗磨损、磨粒脱落和磨耗以及结合剂磨耗磨损,砂轮磨削比约为205.4、405.1、96.0,工件表面粗糙度为0.314、0.337、0.454μm。 相似文献
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Tetraacetyldibenzylhitane (TADBIW) was subjected to debenzylation by nitrosating with inorganic materials available commercially to synthesize tetraacetyldinitrosohexaazaisowurtzitane (TADNSIW). TADNSIW was purified, and its structure was determined by FTIR, 1H NMR, MS and element analysis. The debenzylation reaction of TADBIW gave quantitative benzaldehyde as a by-product. This indicates that the reaction produces an imine cation as an intermediate. Hexanitrohexaazaisowurtzitane (HNIW) was prepared from unpurified TADNSIW with the yield over 96.0 % and the purity more than 98.0 %. And the mechanism of the reaction from TADNSIW to HNIW is proposed to be oxidation of nitroso and nitration of acetyl on the molecule of TADNSIW, This reaction system involved is simple, and the reaction can complete within a short time and under mild conditions. The product can be easily to separate and the waste disposed readily. 相似文献
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The technique of watermarking has been introduced into 2D vector maps for many potential applications such as protecting the copyright of important GIS (geographical information system) data and tracing the data source of military maps. In most previous works, although the validity of the map data could be preserved during the embedding procedure, the shape-distortions of the map elements are usually neglected which would tend to degrade the invisibility of the watermarking schemes. A shape-preserving algorithm for watermarking 2D vector maps is presented in this paper. A 1D distance sequence extracted from the original map is adopted as the cover data instead of 2D coordinates. A watermark bit is represented by changing the distributions of the cover data. The embedding procedure induces lower shape-distortions than in former works. Experimental results indicate better invisibility of the proposed scheme, as well as its robustness to certain attacks such as map simplification, interpolation, additive noise and most geometric transforms. 相似文献
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Open rule-setting method advanced in this paper concentrates on providing designers of engines with a convenient way to express their design innovations and develop the expected prototypes in the early CAD stage, and constitute effective models for the following analysis process of CAE and CAPP. The problems arisen in the process of conceptual design with the traditional experience-based development method are analyzed. Based on those analyses, open rule-setting method is presented and some associated technical problems are discussed. The functional framework of open rule-setting system was built as software engineering methods. The speciality of the engine product as a kind of complex product and the requirement of the engine product based on its structural particularity to rule-setting system are considered carefully. A demonstration is supplied to illustrate how the open rule-setting method enhances the efficiency and quality of the engine conceptual design. 相似文献
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By analyzing the working principle of Linux network device driver, discussing the Linux network driver structure and its key technologies, the general network driver structure and its design methodologies in Linux system are summarized. Through modifying the network device driver of Linux device driver 3rd version snull, c and improving the COW technology, the Zero-Copy technology in Linux (kernel version 2.6.11 ) is implemented. In the end, the success test tells us that the thorough analysis of network device driver is the foundation of many applications, and it also provides a certain improvement to a lot of real applications, even to military application development. 相似文献
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For measuring velocity and impacting position of single fragment of warhead, a non-contact measuring method is proposed, in which a six-light-screen array, a position indicator, a multi-channel chronograph and a computer are used.The principle of measurement is described. The key device of the system is a light screen array sensor which consists of six light screens allocated with certain geometrical parameters. When the fragment flies through the light screen array, the time of passing through each of the screens is recorded by the multi-channel chronograph. According to the time data and the geometrical parameters of the array, the velocity vector and the location of the fragment can be calculated immediately. The presented method can be used to locate the fragment and to measure the real velocity on its flying direction. It can also be used to measure the velocity of a fragment swarm after the system is engineered further. 相似文献
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阐述了数码电子雷管中,点火药剂细结晶三硝基间苯二酚铅(LTNR)的制备工艺;从点火药剂的种类、加入黏合剂的质量分数、桥丝直径、点火头的电阻值、防潮漆的蘸涂等方面对点火头性能的影响因素进行了探讨;通过震动试验、并联起爆试验、延期精度检测与考核,试验结果表明:一次性合成的细结晶LTNR是制造数码电子雷管点火头较为理想的点火药剂,按技术要求生产的点火头性能指标能够满足行业标准要求。 相似文献
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By analyzing the influencing factors of part quality making of sheet alloy of titanium by vibra cutter, the shape of upper reamer is set as cylinder and wedge-shaped form, and the lower reamer as plain and hemicycle form, and its main structural parameters are defined as well. Then it is validated further that such improved vibra cutter reamer can be used to process curve-edged parts of titanium alloy sheet. The experimental result shows that the titanium alloy sheet parts processed by above equipment have no sharpen angles for convex parts and evident crevasse of concave-edged part. In summary, such improvement can eliminate the free-waved edge and improve the manufacture quality of titanium alloy sheet parts greatly. 相似文献
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The initiating behavior of fine-grained explosives by small flyer is studied. The diameter of small flyer in this device is 1 ram. The test results indicate that the granularity of explosives has great effect on its flyer initiating sensitivity.The flyer initiating sensitivity of the fine-grained explosives is higher and the critical initiating energy is lower than that of common explosives. For common explosive, the flyer initiating sensitivity increases as the density is reduced. But for the fine-grained explosive, the test results are exactly opposite. 相似文献
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Multi-laser-target tracking is an important subject in the field of signal processing of laser warners. A clustering method is applied to the measurement of laser warner, and the space-time fusion for measurements in the same cluster is accomplished. Real-time tracking of multi-laser-target and real-time picking of multi-laser-signal are introduced using data fusion of the measurements. A prototype device of the algorithm is built up. The results of experiments show that the algorithm is very effective. 相似文献
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A method to calculate the surface shape error, which is caused by the installing error between the workpiece and the lapping tool in the process of form lapping, is proposed. The mathematical model which the installing translation error influences on the workpiece surface shape error is established. The changing rule of the error is simulated through the calculating example of the paraboloid workpiece. The results indicate that the surface shape error of the workpiece is increasing with the increase of the installing translation error, it is also increasing gradually along the center point of the curve surface to the edge, and the influence is severer to the curve surface with great curvature than that of the small curvature when the translation error is the same. 相似文献