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由于半球谐振陀螺(HRG)特殊的工作原理、制作工艺及装配误差对陀螺精度和性能的影响,需控制电路对其进行修正和补偿,现有半球谐振陀螺控制电路对陀螺的精度提高有限,仅达0.07(°)/h。该文主要阐述了半球谐振陀螺在力平衡模式下的工作原理,对半球谐振陀螺的误差进行了分析,介绍了比例、积分、微分(PID)控制算法,并对所设计的数字控制回路进行分析。试验结果表明,采用该数字控制回路设计方案能有效改善半球谐振陀螺性能,与已有控制电路比,陀螺精度可达0.005(°)/h,更好地满足了其应用于航空领域的精度要求。 相似文献
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光纤陀螺惯导系统在进行空间自主导航时,需要经历长期复杂的空间环境,这会使惯性仪表的某些性能发生变化,光纤陀螺仪的光功率下降是一种比较典型的失效模式,这会导致光纤陀螺仪的带宽下降,当航天器进行变轨或姿态机动时其导航精度会降低。针对上述问题,文中提出了微粒群优化的光纤陀螺仪动态补偿方法,根据光纤陀螺仪和参考模型在相同输入下的响应,优化得到补偿环节的参数。但微粒群算法存在过早陷入局部最优解的缺陷,为提高算法的全局搜索能力,采用模拟退火算法使其以较大的概率跳出局部最优解。通过光纤陀螺导航系统的动态导航试验验证了该方法能够有效地补偿光纤陀螺仪的动态特性,提高机动条件下的导航精度,具有较强的工程实用价值。 相似文献
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为了提高捷联惯导导航精度,构建一种Kalman滤波模型来估计陀螺常值漂移和加速度计零偏。首先分析了载体作单轴正、反旋转运动时,捷联惯导的系统误差特性,然后以正、反旋转两过程中的姿态误差和速度误差为状态变量,以两过程中同一位置处的姿态误差差值和速度误差和值为观测变量,构建了一种Kalman滤波模型,来估计惯性器件常值误差;经可观测性分析,该模型是可观测的。仿真实验中,对于3个陀螺漂移均为0.1(°)/h、加速度计零偏均为9.78×10~(-3 )m/s~2的捷联惯导,陀螺漂移估计精度达到0.01(°)/h,水平方向加速计零偏估计误差均小于0.4×10~(-3 )m/s~2,实验证明该方案可行。 相似文献
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随着惯性系统对陀螺仪精度要求的不断提高,对陀螺漂移的研究日显重要。惯导系统的陀螺仪漂移包括系统性和随机性误差。其中随机性漂移误差是系统的主要误差源。建立陀螺仪随机时序模型,运用卡尔曼滤波算法来消除陀螺漂移中的随机噪声是提高捷联惯导精度的有效途径。卡尔曼滤波是一套由计算机实现的实时递推算法,它所处理的对象是随机信号,在实时性方面有突出的性能。本文将讨论卡尔曼滤波在陀螺仪漂移的滤波算法,并针对型号为ADXRS150的陀螺仪数据进行了处理,得到了较好的效果。 相似文献
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半球谐振陀螺是一种高精度的惯性器件,在航空航天等领域有着重要的应用,但其本征带宽较低,对其力平衡控制回路及带宽测试方法要求较高。该文提出一种新型的基于虚拟科里奥利力的半球陀螺带宽电学快速测试方法,可代替角振动台等昂贵仪器对半球陀螺进行迅速自标定,从而为半球陀螺的高性能控制回路设计方法和批量化测试提供一种新的技术解决方案。首先在基础理论层面分析半球谐振陀螺动力学方程,建立起本征带宽系统模型,为虚拟电旋转的引入和自标定方法提供了理论基础。随后设计了基于虚拟科氏力的电旋转激励信号,并将其集成到陀螺接口电路系统中。最后设计了力平衡控制回路,并对该电学自标定方法进行了实验验证。实验结果表明,虚拟电旋转法能在不借助外部设备的情况下,有效准确地对半球陀螺带宽进行测试和标定,从而有效地促进高性能力平衡控制方法的开发和提高半球陀螺带宽测试效率。 相似文献
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Michael Reilly 《半导体技术》2004,29(12)
DUV lithography, using the 248 nm wavelength, is a viable manufacturing option for devices with features at 130 nm and less. Given the low kl value of the lithography, integrated process development is a necessary method for achieving acceptable process latitude. The application of assist features for rule based OPC requires the simultaneous optimization of the mask, illumination optics and the resist.Described in this paper are the details involved in optimizing each of these aspects for line and space imaging.A reference pitch is first chosen to determine how the optics will be set. The ideal sigma setting is determined by a simple geometrically derived expression. The inner and outer machine settings are determined, in turn,with the simulation of a figure of merit. The maximum value of the response surface of this FOM occurs at the optimal sigma settings. Experimental confirmation of this is shown in the paper.Assist features are used to modify the aerial image of the more isolated images on the mask. The effect that the diffraction of the scattering bars (SBs) has on the image intensity distribution is explained. Rules for determining the size and placement of SBs are also given.Resist is optimized for use with off-axis illumination and assist features. A general explanation of the material' s effect is discussed along with the affect on the through-pitch bias. The paper culminates with the showing of the lithographic results from the fully optimized system. 相似文献
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Thomas M.Trexler 《半导体技术》2004,29(5)
From its emergence in the late 1980s as a lower cost alternative to early EEPROM technologies, flash memory has evolved to higher densities and speedsand rapidly growing acceptance in mobile applications.In the process, flash memory devices have placed increased test requirements on manufacturers. Today, as flash device test grows in importance in China, manufacturers face growing pressure for reduced cost-oftest, increased throughput and greater return on investment for test equipment. At the same time, the move to integrated flash packages for contactless smart card applications adds a significant further challenge to manufacturers seeking rapid, low-cost test. 相似文献
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The relation between the power of the Brillouin signal and the strain is one of the bases of the distributed fiber sensors of temperature and strain. The coefficient of the Bfillouin gain can be changed by the temperature and the strain that will affect the power of the Brillouin scattering. The relation between the change of the Brillouin gain coefficient and the strain is thought to be linear by many researchers. However, it is not always linear based on the theoretical analysis and numerical simulation. Therefore, errors will be caused if the relation between the change of the Brillouin gain coefficient and the strain is regarded as to be linear approximately for measuring the temperature and the strain. For this reason, the influence of the parameters on the Brillouin gain coefficient is proposed through theoretical analysis and numerical simulation. 相似文献
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The parallel thinning algorithm with two subiterations is improved in this paper. By analyzing the notions of connected components and passes, a conclusion is drawn that the number of passes and the number of eight-connected components are equal. Then the expression of the number of eight-connected components is obtained which replaces the old one in the algorithm. And a reserving condition is proposed by experiments, which alleviates the excess deletion where a diagonal line and a beeline intersect. The experimental results demonstrate that the thinned curve is almost located in the middle of the original curve connectivelv with single pixel width and the processing speed is high. 相似文献
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Today, micro-system technology and the development of new MEMS (Micro-Electro-Mechanical Systems) are emerging rapidly. In order for this development to become a success in the long run, measurement systems have to ensure product quality. Most often, MEMS have to be tested by means of functionality or destructive tests. One reason for this is that there are no suitable systems or sensing probes available which can be used for the measurement of quasi inaccessible features like small holes or cavities. We present a measurement system that could be used for these kinds of measurements. The system combines a fiber optical, miniaturized sensing probe with low-coherence interferometry, so that absolute distance measurements with nanometer accuracy are possible. 相似文献
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Qi-jiang Ran Pei-de Han Yu-jun Quan Li-peng Gao Fan-ping Zeng Chun-hua Zhao 《光电子快报》2008,4(4):239-242
This paper presents a new method to increase the waveguide coupling efficiency in hybrid silicon lasers. We find that the propagation constant of the InGaAsP emitting layer can be equal to that of the Si resonant layer through improving the design size of the InP waveguide. The coupling power achieves 42% of the total power in the hybrid lasers when the thickness of the bonding layer is 100 nm. Our result is very close to 50% of the total power reported by Intel when the thickness of the thin bonding layer is less than 5 nm. Therefore, our invariable coupling power technique is simpler than Intel's. 相似文献
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Teleportation of an arbitrary unknown N-qubit entangled state under the controlling of M controllers
A new quantum protocol to teleport an arbitrary unknown N-qubit entangled state from a sender to a fixed receiver under M controllers(M < N) is proposed. The quantum resources required are M non-maximally entangled Greenberger-Home-Zeilinger (GHZ) state and N-M non-maximally entangled Einstein-Podolsky-Rosen (EPR) pairs. The sender performs N generalized Bell-state measurements on the 2N particles. Controllers take M single-particle measurement along x-axis, and the receiver needs to introduce one auxiliary two-level particle to extract quantum information probabilistically with the fidelity unit if controllers cooperate with it. 相似文献
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A continuous-wave (CW) 457 nm blue laser operating at the power of 4.2 W is demonstrated by using a fiber coupled laser diode module pumped Nd: YVO4 and using LBO as the intra-cavity SHG crystal With the optimization of laser cavity and crystal parameters, the laser operates at a very high efficiency. When the pumping power is about 31 W, the output at 457nm reaches 4.2 W, and the optical to optical conversion efficiency is about 13.5% accordingly. The stability of the out putpower is better than 1.2% for 8 h continuously working. 相似文献
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It is well known that adding more antennas at the transmitter or at the receiver may offer larger channel capacity in the multiple-input multiple-output(MIMO) communication systems. In this letter, a simple proof is presented for the fact that the channel capacity increases with an increase in the number of receiving antennas. The proof is based on the famous capacity formula of Foschini and Gans with matrix theory. 相似文献
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《中国通信》2014,(7)
正Wireless Body-area Networks The last decade has witnessed the convergence of three giant worlds:electronics,computer science and telecommunications.The next decade should follow this convergence in most of our activities with the generalization of sensor networks.In particular with the progress in medicine,people live longer and the aging of population will push the development of wireless personal networks 相似文献