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基于BP神经网络的光纤陀螺仪温度建模研究 总被引:6,自引:2,他引:6
目前光纤陀螺应用广泛,但是其性能容易受到环境温度影响,从而影响到惯性导航系统的性能.光纤陀螺的温度特性具有非常复杂的非线性特点,而BP神经网络具有良好的逼近复杂非线性函数能力。使用BP神经网络建立光纤陀螺温度特性的黑箱模型,不对零漂和标度因子进行补偿,而直接对陀螺输出进行校正.经实际数据检验,该建模补偿方法比未经补偿和经过传统工程补偿方法的精度提高了两个数量级.与传统的线性模型相比较,本文基于BP神经网络建立的光纤陀螺温度模型具有补偿方法简单,精度高,通用性好等优点. 相似文献
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捷联惯性导航系统误差参数标定的准确程度对于系统的导航和定位精度具有重要影响.针对常规速率标定法不能辩识陀螺零偏,未充分预热时光纤陀螺的误差标定易受温度变化影响这两个问题,提出了一种用于光纤陀螺捷联惯性导航系统的新标定算法--自适应递推最小二乘法(ARLS).在建立光纤陀螺误差及其补偿模型的基础上,通过大量温度实验研究了自适应遗忘因子的求取方法,详细推导了ARLS算法及其实现思路.最后通过算法仿真和速率试验证明了在器件特性不稳定条件下,ARLS算法能有效辨识陀螺的误差参数及减小温度变化对光纤陀螺误差标定的影响. 相似文献
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高精度光纤陀螺信号的在线建模与滤波 总被引:2,自引:1,他引:2
针对高精度光纤陀螺随机误差,在分析其一般时间序列模型的基础上,提出了一种改进型二阶自回归AR(2)模型,可以在线建立光纤陀螺随机误差模型.根据该模型,采用卡尔曼滤波算法,实现了光纤陀螺惯导系统在对准与导航过程中光纤陀螺随机误差的实时滤波.滤波结果和Allan方差分析证明,光纤陀螺信号中角随机游走、零偏不稳定性、速率随机游走、速率斜坡和量化噪声五项噪声源误差系数都小于滤波前的二分之一,有效减小了光纤陀螺随机误差,提高了光纤陀螺精度. 相似文献
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弹载光纤陀螺旋转惯组误差自补偿技术 总被引:1,自引:1,他引:0
目前弹载惯性测量组合测试标定精度受外界干扰影响较大,特别是光纤陀螺温度稳定性低,易受环境温度影响参数变化,导致误差补偿效果不好。针对该问题,提出设计一种光纤陀螺旋转惯性测量组合。在惯性测量组合外加旋转轴,在导弹飞行过程中使惯性测量组合绕旋转轴连续旋转,将射前补偿不完全误差调制为周期项,从而达到误差自补偿的效果。理论分析和仿真结果表明,通过旋转不仅能自动补偿与转轴垂直方向惯性仪表的常值误差和部分安装误差,而且能补偿加速度计部分一次项误差、二次项误差和部分交叉轴耦合项误差,选择合适的旋转方案还可以完全消除旋转速度与陀螺仪标度因数误差、安转误差的耦合误差。 相似文献
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A novel adaptive forward linear prediction (FLP) denoising algorithm and a temperature drift modeling and compensation concept based on ambient temperature change rate for fiber-optic gyroscope (FOG) are presented to calibrate the errors caused by intense ambient temperature variation. The intense ambient temperature variation will bring large temperature errors, which will degrade the performance of FOG. To analyze the temperature variation, characteristics of FOG temperature experiments are developed at first. Then the adaptive FLP denoising algorithm is employed to eliminate the noise aiming at reducing noise interference. After that, a simple modeling concept of building the compensation model between temperature drift and ambient temperature change rate is first to be given (we have not found a report of better results in any literature). The semiphysical simulation results show that the proposed method significantly reduces the noise and drift caused by intense ambient temperature variation. 相似文献
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Xiaobin Xu Zhihao Zhang Xiong Pan Ningfang Song Chunxi Zhang 《Journal of Modern Optics》2017,64(5):451-456
We propose a double-eigenfrequency-based method to determine the magnitude of the mode-mismatch-induced secondary waves in integrated optic chip in a fibre optic gyroscope (FOG). The experimental results show that the mode-mismatch-induced secondary waves have a magnitude corresponding to power coupling of ~?91.5 dB in the IOC. Based on the obtained secondary waves’ magnitude, the effect of secondary wave-induced intensity modulation on the FOG performance is investigated, and the simulation results show that it causes a scale factor error of ~0.01 ppm for a high-precision FOG (bias stability ~0.001 °/h). 相似文献
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提高混凝土无损测强曲线拟合精度的措施研究 总被引:1,自引:0,他引:1
研究了提高混凝土无损检测测强曲线拟合精度的方法.提出,在最小二乘法的基础上,选用合适的函数形式,采用分段拟合,以相对误差最小为目标,消除异常值的影响或采用人工神经网络等方法,提高测强曲线拟合的精度. 相似文献
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本文旨在论述一种新的、简便有效的曲面拟合方法,该方法是建立在拉格朗日三次曲线拟合方法之上,通过在x和y两个方向同时作曲线拟合,构成一个空间曲面。文中还讨论了该空间曲面的成像技术。经编程验证,此法具有计算量小,拟合精度高,拟合出的曲面光滑等优点,有很好的实用价值。 相似文献
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The perturbed gamma process (PGP) has recently been widely used in modeling the noisy degradation data collected from engineering structures and components since it can simultaneously consider the temporal variability of degradation and measurement uncertainty. As a result of the sampling and inspection uncertainty in engineering practice, it is necessary to account for the resulting parameter uncertainty. Meanwhile, the flexibility of the form of measurement error motivates a potential demand for quantifying the model uncertainty and selecting the most fitting error model for the given inspection data. The Bayesian approach is well-suited to quantity the parameter uncertainty induced by imperfect inspection and limited inspection data, but its practical implementation is extremely challenging due to the intractable likelihood function of PGP. In the paper, a novel Bayesian framework for quantifying parameter and model uncertainty of PGP is presented, where the simulated likelihood that is an unbiased estimator generated by Sequential Monte Carlo (SMC) is introduced to overcome the intractable likelihood of PGP. More specifically, an Adaptive Particle Markov chain Monte Carlo (APMCMC) is proposed to perform the Bayesian sampling from the posterior distributions of parameters, achieving the requirement for the quantification of parameter uncertainty. By utilizing the posterior samples from APMCMC, a model selection method based on the Bayes factor is employed to determine the most fitting one from some alternative error models. Finally, two simulation examples are presented to illustrate the efficiency and accuracy of the proposed framework and its applicability is confirmed by a practical case involving the corrosion modeling of a group of pipelines. 相似文献
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基于AutoCAD的齿轮造型方法研究 总被引:6,自引:0,他引:6
为解决渐开线齿轮的精确造型问题,提出了齿廓渐开线曲线的计算公式。基于 AutoCAD 的 ActiveX Automation 接口与 Visual Basic 编程语言,采用非均匀有理 B 样条拟合方法,实现了齿廓曲线的自动生成。在齿廓基础上,利用 AutoCAD 实体建模功能创建齿轮三维模型。该方法可以提高渐开线齿轮造型精度与效率,从而为渐开线齿轮的有限元分析提供了必要条件。 相似文献
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针对传统最近迭代点(ICP)算法存在配准精度较低的问题进行算法改进。首先,考虑到三坐标测量机测量数据呈现有序排列、且一一对应的特点,使用了一种基于矢量对齐法的型线数据初配准方法进行初配准;其次,在传统ICP算法配准的基础上,对待配准数据进行非均匀有理化B样条(NURBS)曲线拟合,再利用自适应粒子群算法对测量数据进一步精配准;最后,采用基于最小区域的叶片型线轮廓度误差评定方法进行误差评定。实验分析结果表明:改进方法相对于传统ICP算法,可在原有收敛值基础上达到进一步收敛的效果,轮廓度误差相对减小28.57%。该方法有效提高了叶片型线轮廓度误差评定的精确度,可为叶片的加工质量提供可靠判定。 相似文献
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Identification of material constitutive parameters is critical for accurate representation of the mechanical behavior of materials at high strain rates. However, customary characterization procedures based on curve fitting of stress‐strain curves, in some cases, are not accurate when the mechanical response exhibits strain rate dependency. In this paper, an inverse characterization technique based on the Taylor impact test is proposed. The technique uses a data reduction operator based on line moments and genetic algorithm optimization to determine the optimum constitutive parameters. Material parameters for a low carbon steel associated with the Plastic Kinematic model were determined using the proposed method. 相似文献
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在分析炭黑/橡胶复合材料生热率随温度、频率变化的基础上,建立了人工神经网络模型,并将神经网络模型与二次回归拟合公式相比较,进行误差分析,仿真结果表明神经网络模型的精度高于二次回归拟合公式的精度.并探讨了将人工神经网络理论引入到炭黑/橡胶复合材料热物性参数研究领域的可行性. 相似文献