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空间微重力磁悬浮平台激励器研究 总被引:3,自引:0,他引:3
为满足空间实验室的科学实验载荷对微重力环境水平的要求,需要保证空间微重力实验载荷平台的振动隔离性能,即需要平台激励器能在控制系统的作用下适时地产生抑制平台扰动的激励力.本文提出了平台激励器的初步指标,从磁悬浮基本原理出发设计出多种结构形式,在此结构基础上完成有限元磁路仿真和激励器的线圈设计,并对各种结构形式进行比较,根据比较结果总结出各结构形式的优缺点,为激励器的具体设计提供了依据. 相似文献
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飞行器自适应控制参考模型建立方法研究 总被引:1,自引:0,他引:1
针对模型参考自适应控制中参考模型的建立问题,探讨了三种模型设计方法:经典控制设计、最优化控制设计和利用Wonham可控标准型设计,并通过仿真算例比较了三种方法在飞行品质、飞机特性、匹配性和算法性能上的优劣,为模型参考自适应控制系统中参考模型的建立提供了理论依据. 相似文献
85.
就如何撰写建标报告和正确填写申请表进行了详细的描述,并就作者在审核企事业单位建标报告和申请表的过程中所发现的问题进行了归纳总结,旨在帮助参与撰写工作的专业技术人员按照规范的要求和正确的思路完成高质量的技术报告撰写工作。 相似文献
86.
D. Mori A.V. Koustov 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2013
In this study SuperDARN Cross Polar Cap Potentials (CPCPs), collected over the year 2000, are investigated with a goal to statistically assess its relationship with various parameters of the solar wind and Interplanetary Magnetic Field (IMF). We show that SuperDARN CPCPs tend to cluster around discrete values, prescribed by the statistical model, unless the amount of points on each convection map is above ∼300. By selecting CPCP data obtained with radar coverage of >300 points, we investigate the CPCP relationship with IMF Bz and By, IMF clock angle, solar wind speed and dynamic pressure, Alfven velocity, Alfven–Mach number, and interplanetary electric field. Some reported tendencies, such as dependence upon IMF Bz, were found to be consistent with measurements by other instruments. We demonstrate that SuperDARN CPCPs show consistency with several theories/empirical models (predicting the CPCP) in terms of a linear trend but, on average, the slopes of the dependencies are at least two times smaller. We also determine the coupling function, out of those published in literature, best correlating with SuperDARN CPCPs. 相似文献
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Ovidiu Maris Georgeta Maris 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2005,35(12):2129-2140
The high-speed plasma streams in the solar wind are investigated during the solar cycles nos. 20–22 (1964–1996), separately on the two types of streams according to their solar origin: the HSPS produced by coronal holes (co-rotating) and the flare-generated, in keeping with the classification made in different catalogues. The analysis is performed taking into account the following high-speed stream parameters: the durations (in days), the maximum velocities, the velocity gradients and, the importance of the streams. The time variation of these parameters and the high-speed plasma streams occurrence rate show an 11-year periodicity with some differences between the solar cycles considered. A detailed analysis of the high-speed stream 11-year cycles is made by comparison with the “standard” cycles of the sunspot relative number (Wolf number). The different behaviour of the high-speed stream parameters between even and odd solar cycles could be due to the 22-year solar magnetic cycle. The increased activity of the high-speed plasma streams on the descendant phases of the cycles, regardless of their solar sources, proves the existence of some special local conditions of the solar plasma and the magnetic field on a large scale that allow the ejection of the high energy plasma streams. This fact has led us to the analysis the stream parameters during the different phases of the solar cycles (minimum, ascendant, maximum and, descendant) as well as during the polar magnetic field reversal intervals. The differences between the phases considered are pointed out. The solar cycles 20 and 22 reveal very similar dynamics of the flare-generated and also co-rotating stream parameters during the maximum, descendant and reversal intervals. This fact could be due to their position in a Hale Cycle (the first component of the 22-year solar magnetic cycle). The 21st solar cycle dominance of all co-rotating stream parameters against the 20th and 22nd solar cycle ones, during almost all phases, could be due to the same structure of a Hale Cycle – solar cycle 21 is the second component in a 22-year SC. During the reversal intervals, all high-speed stream parameters have comparable values with the ones of the maximum phases of the cycles even if this interval contains a small part of the descendant branch (solar cycles 20 and 22). 相似文献
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本文研究飞机极曲线试飞及其与风洞的相关性问题.主要通过动态飞行获得飞机极曲线(C_y≤0.3)的飞行数据.飞行条件:高度为3~12 km;M数为0.8,0.9,1.2,1.8.结果表明:动态飞行技术是可行的,飞行极曲线与风洞极曲线的相关性较好. 相似文献
89.
针对如何部署光学探测设备才能更好实现对空间目标的高精度高频度监视问题,考虑光照条件、相对关系及探测性能,构建了天/地基空间目标探测与成像仿真模型;按照轨道特征选取了94颗LEO(Low Earth Orbit,低地球轨道)卫星、63颗GEO(Geosynchronous Earth Orbit,地球同步轨道)卫星和18颗大椭圆轨道卫星,选用春夏秋冬典型季节的特定时间长度,仿真分析了国内地基、南北极科考站、LEO卫星、准GEO卫星等多平台光电手段的位置探测和成像观测能力;比对分析地基平台纬度和季节、天基平台轨道高度和倾角对探测能力的影响得出:南北极科考站相比于国内站点可提高重点季节的探测时效性,98°倾角LEO平台对低轨目标成像时效性方面更具优势,等.在此基础上,提出了我国空间目标光电观测设备天地一体的布局构想. 相似文献
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