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基于巨磁阻抗效应(GMI)的磁强计是近年来磁强计研究领域的热点. 相比其他类型磁强计, GMI磁强计具有微型化、高灵敏度、快速响应、高温度 稳定性和低功耗的优点. 本文以铁基纳米晶带材为敏感材料, 设计并实现了GMI 磁强计传感器与后续信号处理电路, 组成一台GMI磁强计. 实验结果表明, 该磁 强计在-25000~25000nT量程内灵敏度为0.176mV·nT-1, 满足实际弱磁场测量要求, 并且具有体积小及功耗低的特点, 有望应用于空间 探测等磁测量领域. 相似文献
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火星磁场测量是国际火星探测任务的焦点之一,中国首次火星磁测任务通过在巡视器(即火星车)和环绕器上同时搭载磁强计,实现对火星磁场的火–空联合观测。巡视器磁强计载荷选用双探头三轴磁通门磁强计,采用亥姆霍兹补偿线圈型探头技术和全数字闭环反馈电路技术,实现空间磁场的高精度同点测量。单机在设计上考虑了可靠性安全性设计和空间环境适应性设计。经地面标定,单机量程可达到±6.5万nT,噪声水平优于0.01 nT/√Hz,分辨率达到了0.01 nT。 相似文献
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针对铯光泵磁强计对原子气室温度高稳定性及无磁干扰的要求,设计了一种用于铯光泵磁强计的无磁恒温控制系统。该系统主要包括无磁加热器件与无磁恒温控制电路。无磁加热器件采用微机电系统工艺的双层对称四线结构,可有效抑制电流产生的磁场;无磁恒温控制电路通过交流加热进一步减小恒定磁场干扰,以现场可编程门阵列为核心,使用直接数字式频率合成技术产生高频加热信号,再经功率放大进行无磁恒温控制,减少硬件电路资源。测试结果表明,气室恒温控制的温度噪声峰峰值可达到0.02 ℃,满足光泵磁强计的性能要求。 相似文献
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萤火一号卫星将对火星空间环境磁场实施探测. 火星磁场对火星弓激波、磁鞘、电离层、大气等绝大多数空间环境效应都具有重要影响, 萤火一号对火星磁场的探测是通过搭载于其上的科学载荷磁强计来实现的. 此磁强计在工作原理及具体设计上, 考虑了火星轨道严酷的工作环境和科学目标所需的测量要求. 通过装星前的地面标定测试, 验证了萤火一号磁强计可以在-130~75°C温度范围内测量±256 nT以内的磁场, 分辨率可达到0.01 nT, 带宽内总噪声小于0.03 nT, 能够满足萤火一号对火星空间环境探测的需求. 相似文献
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介绍一种用于原子磁强计原子气室的无磁加热温控系统设计。针对温控系统加热电流产生的磁场干扰,设计了双层加热丝加热膜结构的加热器件,该加热器件利用同层平行反向电流和层间平行反向电流产生的磁场相互抵消以减小加热电流磁场噪声;设计了滑动平均滤波器对采集的温度信号实施滤波以减小随机噪声的干扰;结合设计的高频加热信号的产生电路、幅度控制电路和功率放大电路开展了实验测试。测试结果表明,研制的双层加热丝加热膜结构加热器件相比单层加热丝加热膜结构加热器件的电流磁场噪声抑制能力提高了约16倍,实现的无磁加热温控系统的温控能力达到1. 2‰。 相似文献
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介绍一种用于原子磁强计原子气室的无磁加热温控系统设计。针对温控系统加热电流产生的磁场干扰,设计了双层加热丝加热膜结构的加热器件,该加热器件利用同层平行反向电流和层间平行反向电流产生的磁场相互抵消以减小加热电流磁场噪声;设计了滑动平均滤波器对采集的温度信号实施滤波以减小随机噪声的干扰;结合设计的高频加热信号的产生电路、幅度控制电路和功率放大电路开展了实验测试。测试结果表明,研制的双层加热丝加热膜结构加热器件相比单层加热丝加热膜结构加热器件的电流磁场噪声抑制能力提高了约16倍,实现的无磁加热温控系统的温控能力达到1.2‰。 相似文献
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火星空间环境磁场探测研究——高精度磁强计 总被引:2,自引:0,他引:2
萤火一号卫星将对火星空间环境磁场实施探测。火星磁场对火星弓激波、磁鞘、电离层、大气等绝大多数空间环境效应都具有重要影响,萤火一号对火星磁场的探测是通过搭载于其上的科学载荷磁强计来实现的。此磁强计在工作原理及具体设计上,考虑了火星轨道严酷的工作环境和科学目标所需的测量要求。通过装星前的地面标定测试,验证了萤火一号磁强计可以在-130~75℃温度范围内测量±256nT以内的磁场,分辨率可达到0.01 nT,带宽内总噪声小于0.03 nT,能够满足萤火一号对火星空间环境探测的需求。 相似文献
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C. Sumners P. Reiff W. Weber 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2008
The Houston Museum of Natural Science, in collaboration with Rice University has an outreach program taking portable digital theaters to schools and community sites for over five years and has conducted research on student learning in this immersive environment. By using an external independent evaluator, the effectiveness of NASA-funded Education and Public Outreach (EPO) projects can be assessed. This paper documents interactive techniques and learning strategies in full-dome digital theaters. The presentation is divided into Evaluation Strategies and Results and Interactivity Strategies and Results. All learners from grades 3–12 showed statistically significant short-term increase in knowledge of basic Earth science concepts after a single 22-min show. Improvements were more significant on items that were taught using more than one modality of instruction: hearing, seeing, discussion, and immersion. Thus immersive theater can be an effective as well as engaging teaching method for Earth and Space science concepts, particularly those that are intrinsically three-dimensional and thus most effectively taught in an immersive environment. The portable system allows taking the educational experience to rural and tribal sites where the underserved students could not afford the time or expense to travel to museums. 相似文献
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C.H. Jaroschek M. Hoshino H. Lesch R.A. Treumann 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2008,41(3):481-490
We address the problem of interacting relativistic current sheets in self-consistent kinetic plasma simulations within the framework of the Particle-In-Cell model. The interaction is enforced in head-on collisions of up to 10 current sheets at relativistic bulk speeds. The simulations are motivated by the general problem of Poynting flux dissipation in ‘striped wind’ configurations presumably governing the relativistic outflows pervasive in pulsar winds and gamma-ray bursts. We identify the generation of non-thermal particles and formation of a stable power-law shape in the particle energy distributions f(γ) dγ ∝ γ−s dγ. In 1D, a spectral index s ∼ 2 is observed and attributed to a stochastic Fermi-type acceleration mechanism. In 2D, the generic index of s ∼ 3–4 is retained as in previous simulations of individual current sheets. Whereas in 2D the high energy cut-off is constrained by the limited dissipation of magnetic energy, in 1D the process converts the bulk motion of current sheets towards directed particle momentum of an exclusive class of non-thermal particles. 相似文献
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G.E. Dorrington 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2011
Various aerial platforms intended for long endurance survey of the Titan surface are presented. A few novel concepts are introduced, including a heated methane balloon and a balloon with a tethered wind turbine. All the concept options are predicted to have lower scientific payload fractions than the Huygens probe. It is concluded that the selection of the best aerial platform option depends on more accurate mass estimates and a clear decision on whether, or not, in situ surface composition measurements are required in conjunction with aerial remote sensing. 相似文献
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H. Cottin P. Coll D. Coscia N. Fray Y.Y. Guan F. Macari F. Raulin C. Rivron F. Stalport C. Szopa D. Chaput M. Viso M. Bertrand A. Chabin L. Thirkell F. Westall A. Brack 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2008
To understand the evolution of organic molecules involved in extraterrestrial environments and with exobiological implications, many experimental programs in the laboratory are devoted to photochemical studies in the gaseous phase as well as in the solid state. The validity of such studies and their applications to extraterrestrial environments can be questioned as long as experiments conducted in space conditions, with the full solar spectrum, especially in the short wavelength domain, have not been implemented. The experiments that are described here will be carried out on a FOTON capsule, using the BIOPAN facility, and on the International Space Station, using the EXPOSE facility. Vented and sealed exposition cells will be used, which will allow us to study the chemical evolution in the gaseous phase as well as heterogeneous processes, such as the degradation of solid compounds and the release of gaseous fragments. 相似文献
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基于LuGre模型的电液加载系统摩擦补偿 总被引:4,自引:2,他引:2
为了提高电液加载系统控制精度,针对摩擦问题提出了基于LuGre摩擦模型的前馈补偿方法.建立了用于摩擦仿真分析和补偿器设计的电液加载系统数学模型;通过实验获取并分析了相关的摩擦数据;基于实验数据进行LuGre模型参数辨识,把LuGre模型和辨识结果引入电液加载系统数学模型,并进行仿真结果与实际摩擦数据的对照,证明了LuGre摩擦模型的准确性.设计前馈补偿器,进行了实验对比,实验结果表明前馈补偿器可将摩擦产生的控制误差有效地降至未补偿时的30%左右. 相似文献
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S. Hekker 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2013
The space-borne observatories CoRoT (Convection Rotation and planetary Transits) and Kepler have provided photometric time series data of unprecedented precision for large numbers of stars. These data have revolutionized the fields of transiting exoplanets and asteroseismology. In this review some important asteroseismic results obtained using data from the CoRoT and Kepler space missions concerning stars that show solar-like oscillations are discussed. These results comprise, among others, measurements of the location of the base of the convection zone and helium second-ionization zone in main-sequence stars, the presence (or not) of core-helium burning in red-giant stars, as well as differential rotation in these stars. 相似文献
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K. Bennett 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1984,3(10-12)
The ESA scientific programme has, so far, provided several significant astrophysics experiments and further important missions are scheduled for execution during the next decade. These missions are briefly summarised together with several astrophysics investigations presently under study. 相似文献
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R.D. Bentley A. Csillaghy J. Aboudarham C. Jacquey M.A. Hapgood K. Bocchialini M. Messerotti J. Brooke P. Gallagher P. Fox N. Hurlburt D.A. Roberts L. Sanchez Duarte 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2011
Heliophysics is a new research field that explores the Sun–Solar System Connection; it requires the joint exploitation of solar, heliospheric, magnetospheric and ionospheric observations. 相似文献
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Yu.A. Surkov 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1981,1(8):21-38
In this report the main results of the study of radioactivity of the solar sistem bodies are considered. The radioactivity of the Moon and planets was measured by means of vehicles in situ. The radioactivity of the lunar samples, brought to the Earth was studied with laboratory equipment. 相似文献
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为了在毫米波波段准确测量波导器件的反射系数,提出了一种应用在反射系数测试前端(反射计)中的校准方法.该校准方法采用基于多项式的误差模型,使得每一个误差项的求解都转化成一个求解轨迹圆圆心的问题,同时不影响求解精度.采用一个滑动负载、一个滑动短路和一个短路器,在毫米波波段降低了对标准件理想程度的要求.实验中搭建了一个Ka波段的反射计,图解误差项的求解过程,分析了误差项的物理意义.把校准后的测量结果与商用矢量网络分析仪(VNA,Vector Network Analyzer)进行比较,吻合较好.同样比较了一组W波段反射计对波纹喇叭的测量结果,进一步验证了方法的合理性. 相似文献