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Benjamin Lenoir Bruno Christophe Serge Reynaud 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2013
The Gravity Advanced Package is an instrument composed of an electrostatic accelerometer called MicroSTAR and a rotating platform called Bias Rejection System. It aims at measuring with no bias the non-gravitational acceleration of a spacecraft. It is envisioned to be embarked on an interplanetary spacecraft as a tool to test the laws of gravitation. 相似文献
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F. Liorzou D. Boulanger M. Rodrigues P. Touboul H. Selig 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2014
The MICROSCOPE mission is fully dedicated to the in-orbit test of the Universality of free fall, the so-called Weak Equivalence Principle (WEP), with an expected accuracy better than 10−15. The test principle consists in comparing the accelerations of two proof masses of different composition in the Earth gravitational field. The payload embarks two pairs of test-masses made of Platinum Rhodium and Titanium alloys at the core of two dedicated coaxial electrostatic accelerometers. These instruments are under qualification for a launch in 2016. 相似文献
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Petro Abrykosov Roland Pail Thomas Gruber Nassim Zahzam Alexandre Bresson Emilie Hardy Bruno Christophe Yannick Bidel Olivier Carraz Christian Siemes 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2019,63(10):3235-3248
The state-of-the-art electrostatic accelerometers (EA) used for the retrieval of non-gravitational forces acting on a satellite constitute a core component of every dedicated gravity field mission. However, due to their difficult-to-control thermal drift in the low observation frequencies, they are also one of the most limiting factors of the achievable performance of gravity recovery. Recently, a hybrid accelerometer consisting of a regular EA and a novel cold atom interferometer (CAI) that features a time-invariant observation stability and constantly recalibrates the EA has been developed in order to remedy this major drawback. In this paper we aim to assess the value of the hybrid accelerometer for gravity field retrieval in the context of GRACE-type and Bender-type missions by means of numerical closed-loop simulations where possible noise specifications of the novel instrument are considered and different components of the Earth’s gravity field signal are added subsequently. It is shown that the quality of the gravity field solutions is mainly dependent on the CAI’s measurement accuracy. While a low CAI performance (10?8 to 10?9?m/s2/Hz1/2) does not lead to any gains compared to a stand-alone EA, a sufficiently high one (10?11?m/s2/Hz1/2) may improve the retrieval performance by over one order of magnitude. We also show that improvements which are limited to low-frequency observations may even propagate into high spherical harmonic degrees. Further, the accelerometer performance seems to play a less prominent role if the overall observation geometry is improved as it is the case for a Bender-type mission. The impact of the accelerometer measurements diminishes further when temporal variations of the gravity field are introduced, pointing out the need for proper de-aliasing techniques. An additional study reveals that the hybrid accelerometer is – contrary to a stand-alone EA – widely unaffected by scale factor instabilities. 相似文献
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印刷电路板的动力学特性直接影响机载电子设备在振动和冲击环境下的工作可靠性,有必要在设计阶段对其进行动力学分析.印刷电路板为薄壁结构,质量一般较小,在使用传统的加速度传感器测量时,传感器的附加质量会对模态测试结果造成影响.通过加速度传感器与激光测振仪测试数据的对比,分析了加速度传感器附加质量对模态测试结果的影响,验证了传感器附加质量消除方法的效果,结论认为传感器附加质量对印刷电路板模态测试的结果影响明显且这种影响不能被完全消除;使用扫描式激光测振仪可以得到精确详细的模态参数. 相似文献
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力矩器磁路性能决定了加速度计标度因数的性能,为此利用有限元方法对力矩器磁路的磁通密度进行分析,在此基础上提出了两种结构优化设计方案,并对其进行仿真计算。仿真结果表明,改变导磁帽的形状可以提高气隙磁场的磁通密度的稳定性和均匀性,但导磁帽易出现饱和现象;通过降低磁钢的高度,同时增加导磁帽的高度,既能大幅度的提高磁场的稳定性和均匀性,导磁帽也不会出现饱和现象,但气隙磁场的磁通密度均值会降低37.25%,非线性误差为1.83%,优化后气隙磁场存在着磁通密度稳定(径向均值为0.42868T)和均匀的区域。 相似文献