共查询到18条相似文献,搜索用时 125 毫秒
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由于静电场的负刚度导致控制回路系统的不稳定,因此静电力闭环硅微加速度计控制系统设计是硅微加速度计技术的关键核心技术,也是硅微加速度计设计的难点技术之一。在硅微加速度计项目研制过程中,我们解决了仪表回路系统的稳定性问题、高增益和带宽的问题,保证了仪表启动的快速性、精度和稳定性。 相似文献
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微机械加速度计发展现状浅析 总被引:1,自引:0,他引:1
自微机电系统(MEMS)技术以IC工艺为基础发展以来,微机械加速度计便作为其中一个耀眼的应用实例大放异彩。在国外,上世纪九十年代就有低精度微加速度计产品,同时国内也开始了相关研究。时至今日,微加速度计已经按高精度、中精度、低精度三个精度等级分别发展。以麻省理工大学(MIT)Draper实验室为代表的一些国外机构已经研制出10-7g级别的高精度微加速度计样机并尝试在潜射导弹、洲际导弹再入等方面取得应用,乃至将来替代高精度摆式积分陀螺加速度计(PIGA);以COLIBRYS、Honeywell等公司为代表的商业机构,依托自身科研能力,致力于将中精度微机械加速度计推出量产化的单表和组合成品并推向低端军用和高端民用市场;以AD、ST等公司为代表的跨国公司,依托自身工艺线,推出大量的微机械加速度计,占领了消费电子市场。国内的研制分工也越来越细化,技术路线、行业分工、研究内容、需求牵引都越来越明确,其中压阻式、热对流式微机械加速度计已经产业化,微机械加速度计已有小批量的产品,硅微谐振式加速度计也显示了很好的发展前景。本文试对发展现状进行了简单评析。 相似文献
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硅微加速度计作为一种新型惯性传感器,它在体积、重量、成本、功耗、可靠性和寿命方面都具有传统加速度计无可比拟的优势。本文阐述了MS8000硅微加速度计结构和工作原理,并对其重要性能参数进行了测试和分析。 相似文献
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微型仿生飞行器的研究涉及仿生学原理、准稳态气动力和原理样机的研制等。概述了上海交通大学针对昆虫尺度的微型仿生飞行器的新颖的设计和加工方法。该方法确保了零部件空间位置的合理安排,从而减少了零部件的装配难度。具体来说,压电驱动器的设计考虑了电气隔离和装配问题;传动机构与机身整合成一个部件,避免了相互之间的装配。翅脉的纤维方向进行了合理的布置,使得翅膀拥有高强度和高刚度。最终,研制的压电驱动微型仿生飞行器重84mg,翼展35mm,在100Hz的拍打共振频率下可以产生±60°的拍打角度,能产生足够的升力实现起飞。 相似文献
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In order to satisfy the machining requirements of aero-engine casing in modern aviation industry, this paper investigates three main issues during the design and development process of a five-axis machine tool with high accuracy, stiffness and efficiency, including whole structure design,key components design, and supporting stiffness design. First, an appropriate structure of five-axis machine tool is determined considering the processing characteristics of aero-engine casing. Then, a dual driv... 相似文献
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G. L. Tyler I. R. Linscott M. K. Bird D. P. Hinson D. F. Strobel M. Pätzold M. E. Summers K. Sivaramakrishnan 《Space Science Reviews》2008,140(1-4):217-259
The New Horizons (NH) Radio Science Experiment, REX, is designed to determine the atmospheric state at the surface of Pluto and in the lowest few scale heights. Expected absolute accuracies in n, p, and T at the surface are 4?1019 m?3, 0.1 Pa, and 3 K, respectively, obtained by radio occultation of a 4.2 cm-λ signal transmitted from Earth at 10–30 kW and received at the NH spacecraft. The threshold for ionospheric observations is roughly 2?109 e??m?3. Radio occultation experiments are planned for both Pluto and Charon, but the level of accuracy for the neutral gas is expected to be useful at Pluto only. REX will also measure the nightside 4.2 cm-λ thermal emission from Pluto and Charon during the time NH is occulted. At Pluto, the thermal scan provides about five half-beams across the disk; at Charon, only disk integrated values can be obtained. A combination of two-way tracking and occultation signals will determine the Pluto system mass to about 0.01 percent, and improve the Pluto–Charon mass ratio. REX flight equipment augments the NH radio transceiver used for spacecraft communications and tracking. Implementation of REX required realization of a new CIC-SCIC signal processing algorithm; the REX hardware implementation requires 1.6 W, and has mass of 160 g in 520 cm3. Commissioning tests conducted after NH launch demonstrate that the REX system is operating as expected. 相似文献
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分体式石英谐振加速度传感器在性能提升上受到装配误差等因素的影响较大,故提出一种全石英谐振加速度计芯片结构,包括下层的硅结构和上层的石英结构。下层的硅基底仅作为支撑结构进行加工制作,敏感单元为全石英材料,硅结构与石英结构键合到一起,结构加工完成后去除硅材料,以释放石英敏感单元。整体结构为中心对称,包括质量块、音叉结构、微杠杆结构和应力分配梁,芯片通过微杠杆结构来增大传感器的灵敏度,并通过应力分配梁使石英音叉两根振梁上的内应力均匀一致。通过仿真验证了设计的有效性,仿真的差动灵敏度为35Hz/g。 相似文献
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Marcia Neugebauer 《Space Science Reviews》2013,176(1-4):125-132
A survey of propagating interplanetary shocks reveals the following properties: (1) More shocks are observed around solar-activity maximum than minimum. (2) The maximum frequency of shock occurrence is between 2 and 5 AU. (3) Shocks slow down in the inner solar system, but in the outer solar system some may get a boost in speed when overtaken by a following shock. (4) The average shock strength (as measured by either the Mach number or the density ratio) also reaches peak values at distances of 2–5 AU. (5) Shocks are stronger at their noses than at their flanks. (6) At 1 AU, there are many more quasiperpendicular than quasiparallel shocks with the frequency of occurrence roughly constant with the cosine of the angle between the upstream field and the shock normal. 相似文献