SINS/GPS组合导航的扩展Kalman滤波算法

针对捷联惯性导航系统(SINS)无法长时间单独工作和GPS卫星信号易失锁而无法定位的问题,分析了两种导航系统的优缺点,提出了SINS/GPS组合导航的方法.建立了陀螺和加速度计的误差模型,采用松耦合方式,设计了扩展Kalman滤波器.以姿态、速度、位置的误差以及陀螺、加速度计的误差作为状态变量,对姿态、速度、位置进行校正.运用Matlab对组合导航系统进行了仿真.结果表明,该算法简单,容易实现,能满足导航精度要求.     

Kernel Entropy Based Extended Kalman Filter for GPS Navigation Processing

This paper investigates the kernel entropy based extended Kalman filter (EKF) as the navigation processor for the Global Navigation Satellite Systems (GNSS), such as the Global Positioning System (GPS). The algorithm is effective for dealing with non-Gaussian errors or heavy-tailed (or impulsive) interference errors, such as the multipath. The kernel minimum error entropy (MEE) and maximum correntropy criterion (MCC) based filtering for satellite navigation system is involved for dealing with non-Gaussian errors or heavy-tailed interference errors or outliers of the GPS. The standard EKF method is derived based on minimization of mean square error (MSE) and is optimal only under Gaussian assumption in case the system models are precisely established. The GPS navigation algorithm based on kernel entropy related principles, including the MEE criterion and the MCC will be performed, which is utilized not only for the time-varying adaptation but the outlier type of interference errors. The kernel entropy based design is a new approach using information from higher-order signal statistics. In information theoretic learning (ITL), the entropy principle based measure uses information from higher-order signal statistics and captures more statistical information as compared to MSE. To improve the performance under non-Gaussian environments, the proposed filter which adopts the MEE/MCC as the optimization criterion instead of using the minimum mean square error (MMSE) is utilized for mitigation of the heavy-tailed type of multipath errors. Performance assessment will be carried out to show the effectiveness of the proposed approach for positioning improvement in GPS navigation processing.     

光电跟踪系统非线性新息自适应卡尔曼滤波算法

为解决非线性部分状态卡尔曼滤波算法中由于线性化误差所导致的滤波精度下降问题,提出采用UT变换方法计算系统状态误差方差,及基于新息自适应调整系统噪声方差,进而构成一种新的非线性自适应部分状态卡尔曼滤波算法,并总结出详细算法结构.同时,将此方法应用到非线性测量光电跟踪系统中,并与U卡尔曼滤波和非线性部分状态卡尔曼滤波进行性...     

基于改进扩展卡尔曼滤波算法的静电目标跟踪

针对静电探测的数学模型结构复杂、强非线性以及实验测量数据存在极大不确定性的特点和 ExtendedKalman Filter(EKF)在处理强非线性的测量方程时会出现滤波发散的现象.为了提高滤波精度和减少计算复杂度,采用中心差分的方法计算EKF中的非线性函数的一阶导数,并结合球形静电探测器实际探测的特点形成一种新的改进的EKF算法.将改进后的EKF应用于静电目标的跟踪,建立目标跟踪滤波器.理论分析和仿真表明,采用改进后的EKF与EKF和Unscented Kalman Filter(UKF)相比较,虽然计算时间比EKF稍有增加,但比UKF的计算时间少;而计算精度比EKF有显著提高,与UKF的计算精度相当.     

基于自适应特征融合的多尺度相关滤波跟踪

为了减小目标跟踪中目标变形、光照影响、运动模糊以及目标旋转对跟踪效果的影响,在相关滤波KCF基础上,提出了一种基于自适应特征融合的多尺度相关滤波跟踪算法。首先,提取VGG19网络中conv2-2、conv3-4、conv5-4层的特征以及CN特征,并在conv2-2层加入CN特征;然后,将这3个特征分别代替HOG特征进行滤波学习,得到3幅响应图;进而对3幅响应图进行加权融合预测目标位置。最后,在尺度方面引入多尺度相关滤波器进行尺度的确定。该算法比KCF跟踪算法精确度和成功率分别提高了13.6%和11.8%。与现有的其他优异跟踪算法相比,该算法在应对运动模糊、背景杂乱、目标变形、平面旋转方面更具有较好的跟踪效果。     

基于自适应滤波的锂电池隔膜卷绕系统张力估计

锂电池隔膜卷绕系统的电机转速、放卷辊的卷材卷径和放卷张力等实时信号都带有高斯白噪声,易形成较大的滞后,从而导致控制系统的稳定性和精度降低。现以协方差匹配技术为滤波发散判据,再结合对于指数加权系数的表达式限定记忆滤波的次数,提高噪声初始值的分配权重,来保持滤波的自适应程度,提出一种基于改进型SageHusa自适应滤波估计张力的方法,实现对系统噪声协方差阵与测量噪声协方差阵的自适应变化。实验结果表明,所提出的方法不仅能更准确、稳定地估计出锂电池隔膜卷绕系统放卷张力,还能在一定范围内使其不受给定的噪声协方差阵初值影响,而且有较高的精度和较强的实时性,优于一般的扩展卡尔曼滤波算法。     

交互式多模型集自适应协同滤波目标跟踪算法研究

为了解决传统交互式多模型算法静态模型集带来的精度低等局限问题,提出了一种多模型集自适应协同滤波算法.通过比较目标与当前模型集中不同模型之间的模型匹配概率,自动确定当前模型匹配中的最好模型与最坏模型,利用激活、保留和剔除策略改变固定模型集的结构以达到模型集自适应的过程.通过与其他已经提出的交互式多模型算法进行比较,实验结...     

基于在线学习的自适应粒子滤波视频目标跟踪

传统的粒子滤波视觉跟踪算法采用固定模型和大量粒子表征目标后验概率,不能满足复杂条件下的视频目标实时跟踪.为了提高跟踪的鲁棒性和稳定性及计算效率,本文提出将自适应状态演化方程和在线增量学习观测似然模型嵌入到粒子滤波算法;并采用在线自动调整粒子数目的策略,提高粒子滤波视觉跟踪的计算效率.室内外实验结果表明,文中提出的视觉跟踪算法不仅能准确、高效地跟踪序列图像中的运动目标,而且对光照、姿态变化引起的目标表观变化具有良好的鲁棒性.     

基于模糊逻辑的两步卡尔曼滤波器设计

在对惯性运动跟踪系统的建模分析中,常采用基于计算机的集中式卡尔曼滤波算法进行数据处理。由于该方法存在算法复杂,处理数据速度慢等问题,难以在嵌入式系统中实现高速运动跟踪,提出一种基于模糊逻辑的自适应两步卡尔曼滤波算法。该方法根据人体不同的运动状态调整卡尔曼滤波器,实验结果证明所提的方法能够更好地估计各个传感器的测量精度,减少了运算量,并在一定程度上提高了滤波器的容错性能。     

基于当前统计模型的一种双自适应模糊滤波算法

在当前统计模型的基础上,提出一种双自适应模糊滤波算法.该算法利用模糊推理机制及结合升半正态形模糊分布函数,对最大加速度和过程噪声协方差矩阵进行双自适应调整.针对阶跃机动,引入强跟滤波器达到增强跟踪机动目标的能力.仿真结果表明,该算法提高了机动模型与目标实际机动模型的匹配程度以及对强机动目标跟踪的精度,改善了滤波器的跟踪性能,克服了对弱机动目标跟踪性能的不足.     

Optimization of Adaptive Fuzzy Controller for Maximum Power Point Tracking Using Whale Algorithm

The advantage of fuzzy controllers in working with inaccurate and nonlinear inputs is that there is no need for an accurate mathematical model and fast convergence and minimal fluctuations in the maximum power point detector. The capability of online fuzzy tracking systems is maximum power, resistance to radiation and temperature changes, and no need for external sensors to measure radiation intensity and temperature. However, the most important issue is the constant changes in the amount of sunlight that cause the maximum power point to be constantly changing. The controller used in the maximum power point tracking (MPPT) circuit must be able to adapt to the new radiation conditions. Therefore, in this paper, to more accurately track the maximum power point of the solar system and receive more electrical power at its output, an adaptive fuzzy control was proposed, the parameters of which are optimized by the whale algorithm. The studies have repeated under different irradiation conditions and the proposed controller performance has been compared with perturb and observe algorithm (P&O) method, which is a practical and high-performance method. To evaluate the performance of the proposed algorithm, the particle swarm algorithm optimized the adaptive fuzzy controller. The simulation results show that the adaptive fuzzy control system performs better than the P&O tracking system. Higher accuracy and consequently more production power at the output of the solar panel is one of the salient features of the proposed control method, which distinguishes it from other methods. On the other hand, the adaptive fuzzy controller optimized by the whale algorithm has been able to perform relatively better than the controller designed by the particle swarm algorithm, which confirms the higher accuracy of the proposed algorithm.     

光电跟踪的非线性卡尔曼滤波算法

为得到最小方差意义下的光电跟踪目标的最优状态估计,提出将部分状态卡尔曼滤波和非线性系统的一阶线性化思想相结合,构成一种适用于非线性光电跟踪目标的卡尔曼滤波算法,并总结出详细算法结构.同时将此方法应用到非线性测量光电跟踪系统中,并与扩展卡尔曼滤波和U卡尔曼滤波进行性能对比.仿真实验结果证明,将部分状态卡尔曼滤波和非线性系统的一阶线性化思想相结合是有效可行的,而且其性能明显优于扩展卡尔曼滤波和U卡尔曼滤波.     

An Extended Kalman filter for collaborative supply chains

Supply chains can often be complex due to the large mesh of interconnected suppliers, manufacturers, distributors and customers. Recent advances in communication technologies can help participants collaborate across a supply chain. However, the huge amount of data generated can impede effective decision-making, particularly since some data may be incomplete or have errors. Inaccurate estimates of the state of the supply chain system can lead to incorrect decisions, with consequent adverse effects on product availability, lead times and inventory levels. What would be beneficial in overcoming this problem is an approach to obtain a better state estimation of the supply chain system. The paper aims to address this issue by proposing an approach that combines an extended Kalman filter with a network approach that models the supply chain as an abstraction. This approach is termed Augmented Trans-Nets and has several potential advantages: multiple participants in a supply chain can be modelled without undue complexity; and different considerations can be examined, such as cost and lead time. Furthermore, by using this approach, it is relatively straightforward to achieve an improved system estimation, which can help in managing the supply chain effectively.     

卷积伏安法实验数据的自适应卡尔曼滤波 Ⅰ.数据的平滑

本文研究了自适应卡尔曼滤波技术在新极谱法中的应用。通过极谱法拟合数据试验结果表明,1∶N自适应卡尔曼滤波器用于消除新极谱法实验数据中噪声的干扰,效果极好,其滤波结果具有良好的线性关系。应用于Cd(Ⅱ)的半微分电分析实测数据的处理,取得令人满意的结果。     

基于几何特征点的扩展目标跟踪方法

提出了一种基于几何特征点的扩展目标跟踪方法,该方法借鉴模板匹配跟踪的思想,以目标的几何特征点作为模板进行目标跟踪.把多尺度Harris特征点检测与SIFT描述子相结合,用于几何特征点的提取和描述,接着引入加权相似性度量公式和更新策略以提高特征点的匹配精度,从而实现更加稳定的跟踪.试验表明,该算法可以稳定地跟踪姿态剧烈变化的扩展目标.     

适用于快速扩展目标的跟踪算法

提出了一种算法──偏移质心算法,阐述了偏移质心算法的原理及实现过程。该算法适用于对高速运动扩展目标的跟踪,已成功地用于ＯＦＤ－６３０电视跟踪器,并通过了连云港动态打靶试验。由于这种算法快速简捷、方便易行,且能实时稳定的对目标进行跟踪,在图象跟踪系统中不失为一种简单实用的跟踪算法。     

Extended Kalman filter for estimating aircraft orientation from velocity measurements

A coordinated flight model for estimating the orientation of an aircraft under track from velocity measurements into an extended Kalman filter (EKF) framework is placed here. In doing so, it makes two contributions. First, the EKF provides a rigorous framework for addressing this problem, blending modelling error and measurement error. Second, the EKF supplements the estimated orientation with a measure of the uncertainty in that estimate. Such estimates of uncertainty are crucial in a number of applications, including using the orientation estimates to approximate the radar cross section of the aircraft under track, in an attempt to identify targets. The EKF's performance is demonstrated using both a straight-and-level manoeuvre and a complicated manoeuvre recorded on-board a manoeuvring F-15. In both cases, the state estimates of the EKF are similar to the results obtained from a coordinated flight model. The true orientations almost always fall within one standard deviation of the estimates, as determined by the estimated covariance.     

基于车辆组合导航的集中卡尔曼滤波方法研究

讨论了适用于车辆组合导航的集中卡尔曼滤波方法,根据车辆组合导航的实际情况建立了集中卡尔曼滤波方程,选取了滤波初始值,并进行了位置仿真、速度仿真、位置+速度仿真.由仿真结果对比可以看出位置组合的纬度误差曲线有一定波动,速度组合的经、纬度误差曲线都比较平稳,位置+速度组合的滤波效果优于其它两种组合.     

基于小波分析的惯性传感器信号Kalman滤波

针对光电跟踪系统惯性传感器信号特点,本文提出通过小波分析的方式确定相关Kalman滤波的模型及参数.该方法利用小波分析的优良特性,采用先将信号进行去噪处理,然后对去噪后的信号进行AR建模.根据小波去噪后的信号比较接近真实信号,将得到的观测噪声方差乘以一个小于1的系数后作为系统的过程噪声方差,从而确定模型的噪声参数.仿真实验结果表明,该方法不仅对惯性传感器的静态数据有很好的效果,而且对其动态观测数据也有良好的效果.同时,该方法不仅对光电跟踪系统有效,而且还具有一定的通用性.     

改进的UKF在SINS/GPS/地磁组合导航中的应用

针对SINS(Strapdown Inertial Navigation System)/GPS组合导航系统中出现的滤波发散问题,研究自适应渐消卡尔曼滤波对于滤波发散的抑制作用,引入了一种新的渐消矩阵计算方法.为了提高导航精度,增加了地磁量,作为观测量对运载体的姿态、速度、位置进行校正,有效地解决了SINS初始状态的导航精度下降问题.车载实验证明,该算法简单,容易实现,能够有效抑制滤波发散,满足组合导航的精度要求.