动态卡尔曼滤波在导航试验状态估计中的应用

阐述了GPS动态试验的新方案,使用两个精度相差一个数量级的GPS接收平台,通过匀速运动车辆的DGPS及GPS的滤波对比试验,验证了卡尔曼滤波器的有效性.并针对传统EKF(extended Kalman filtering)滤波器动态滤波性能较差的缺陷,引入了一种基于非线性思想的动态无导数卡尔曼滤波器,并对其状态方差阵及随机噪声方差阵Cholesky分解更新公式做了改进,避免了导数的运算,加快了滤波速度,有效地确保方差矩阵平方根的正定性从而抑止了发散.将这种新的卡尔曼滤波器应用于实际动态定位状态估计问题上.试验结果表明:比起传统卡尔曼滤波器,新的卡尔曼滤波器有较高的精度,实用性更强.     

基于卡尔曼滤波器的索道轿厢相对定位方法及应用

索道轿厢的实时精准定位在客运索道安全运营中至关重要,而GPS信号在索道运营区域常常出现信号不稳定、定位精度不高等问题。提出了一种基于卡尔曼滤波器的索道轿厢相对定位方法,研究了GPS经纬度与索道轿厢位移的换算关系,建立了适合于索道轿厢GPS定位的卡尔曼滤波器模型。实验结果表明:所提出的方法不仅满足了定位精准度,又保证了数据的实时性,其结果符合索道的运营要求。本方法已成功应用于索道行业,为国内诸多知名景区的索道轿厢定位提供了解决方案。     

双渐消Kalman滤波补偿六维力传感器矩形板噪声模型误差

六维力传感器能够通过应变片及板梁结构实时检测空间六方向的力信息,但其输出信号不可避免地被噪声干扰所污染。为改善这一现象,同时针对过程噪声模型不精准致使经典卡尔曼滤波器性能差的问题,设计了一种双因子渐消卡尔曼滤波器。算法研究了加性噪声信号的统计特性,建立了矩形板主振型增广状态方程,分析了两种过程噪声模型偏差对滤波性能的影响。在经典卡尔曼滤波器的基础上,基于新息正交性原理,依据Sage开窗估计原理与最小二乘准则,构造了双渐消因子的解析式,阐述了滤波器的工作原理。研究表明:双渐消卡尔曼滤波器稳定性强,能够有效削弱噪声模型偏差的影响;对比抗差卡尔曼滤波器,精度提升38.66%。     

半主动悬架的无迹卡尔曼状态观测器设计

卡尔曼滤波器是线性动态系统中应用最广泛的一种状态估计方法。在非线性系统中,扩展卡尔曼滤波(EKF)和无迹卡尔曼滤波(UKF)被广泛应用,相比扩展卡尔曼滤波器,无迹卡尔曼滤波器准确度更高、更易于实现。在车辆动力学这种强的非线性系统中,无迹卡尔曼滤波器应用广泛。设计了一种基于无迹卡尔曼滤波器的半主动悬架系统状态观测器,讨论了不准确的过程噪声协方差Q和测量噪声协方差R、及测量信号组合的选择和不准确的模型参数对状态观测精度的影响,仿真结果表明不准确的过程噪声和测量噪声协方差、不合适的测量信号选择和模型参数不准确的干扰在不同程度上降低了状态估计精度。     

卡尔曼滤波器在高频信号注入法中的应用

高频信号注入法估计永磁同步电机转子位置的精度,依赖于高频电流信号的提取.卡尔曼滤波器是对付白噪声的有力工具,本文针对高频注入信号的特点,设计了卡尔曼滤波器,并进行了仿真和实验研究.结果表明,经过卡尔曼滤波器的处理,电流信号信噪比大大提高.     

基于遗传算法的模糊卡尔曼滤波

针对常规联合卡尔曼滤波存在的缺陷,提出基于遗传优化的模糊卡尔曼滤波方法,并运用于全球定位系统(GPS)/轨迹推算系统(DR)汽车组合导航的数据融合中.采用模糊逻辑自适应控制器对联合卡尔曼滤波器的噪声方差和信息分配系数进行在线自适应调整,避免了子滤波器的发散,保持了全局估计的高精度.同时,利用改进的遗传算法来优化模糊控制器的隶属函数,避免了以往完全凭经验获取隶属函数参数的缺陷.通过对GPS/DR组合导航系统的仿真和实验,验证了上述算法的可用性和有效性.     

移动机器人室内外无缝切换定位方法研究

为了实现移动机器人在室内外环境下的无缝精准定位,针对实验室的巡检机器人,安装惯性测量单元(IMU)、GPS、UWB定位传感器模块,在通过容积卡尔曼滤波器实现室内和室外融合定位的基础上提出了基于阈值机制和多传感器定位精度的室内外无缝切换定位方法,并设计实验验证算法在定位精度上的优越性和室内外定位切换上的平稳性.     

基于卡尔曼控制的滑模振动力输出跟随系统

针对振动力输出跟随系统无误差跟随和消除控制系统中经常伴有随机噪声和过程噪声的问题,提出了一种基于卡尔曼滤波器的滑模控制器。设计了滑模面以保证振动力输出的无静差跟踪;采用了指数趋近律提高趋近速度并削弱抖振。针对具有噪声干扰的场合,在控制系统中加入了卡尔曼滤波器消除了传感器测量带来的随机噪声和过程噪声。在Matlab/Simulink平台上,进行了振动正弦输出力跟随控制仿真研究,并且比较了有卡尔曼滤波器和无卡尔曼滤波器的跟踪效果。研究结果表明:基于卡尔曼控制的滑模振动力输出跟随系统具有较强的抗噪性、鲁棒性以及良好的稳态性能。     

一种带遗忘因子的自适应卡尔曼滤波器及其在移动机器人中的应用

在移动机器人姿态估计过程中,由于难以建立准确的系统模型,导致参数量测不准确。采用一种自适应卡尔曼滤波器,通过加入遗忘因子的方式改变滤波器对状态估计的信任程度,改善了系统中噪声统计模型不准确对测量结果的影响。仿真结果表明,当经验知识不足导致建立姿态测量模型不准确时,自适应卡尔曼滤波器的滤波效果优于传统卡尔曼滤波器,提高了姿态信号的估计精度。     

基于LabWindows/CVI的GPS数据采集处理系统

文章在虚拟仪器技术的基础上,设计了GPS数据采集处理系统。介绍了系统设计的关键技术,阐述了其搭建的过程及实现的主要功能。采用LabWindows/CVI 8.0作为系统的软件开发平台,实现了GPS25LVS与上位机的数据通信,并建立了GPS静态定位数据处理的卡尔曼滤波器,提高了GPS的静态定位精度。     

Analysis of a robust Kalman filter in loosely coupled GPS/INS navigation system

GPS/INS integrated system is very subject to uncertainties due to exogenous disturbances, device damage, and inaccurate sensor noise statistics. Conventional Kalman filer has no robustness to address system uncertainties which may corrupt filter performance and even cause filter divergence. Based on the INS error dynamic equation, a robust Kalman filter is analyzed and applied in loosely coupled GPS/INS integration system. The norm bounded robust Kalman filter, with recursive form by solving two Riccati equations, guarantees a estimation variance bound for all the admissible uncertainties, and can evolve into the conventional Kalman filter if no uncertainties are considered. This paper will analyze the suitable case for the robust Kalman filter in GPS/INS system, the filter characteristics including parameter setting, parameter meaning, and filter convergence condition are discussed simutaneously. The robust filter performance will be compared with conventional Kalman filter through simulation results.     

GPS单点定位精度优化方法研究

针对GPS单点定位精度低的问题,提出了一种基于卡尔曼滤波和模糊C-均值聚类的联合定位优化方法.该方法首先对GPS采集到的经纬度数据进行卡尔曼滤波,消除较大的数据波动,然后采用模糊C-均值聚类算法确定数据中心.最后通过实验证明了这种优化方法的合理性和有效性.     

Novel hybrid of strong tracking Kalman filter and wavelet neural network for GPS/INS during GPS outages

Aiming to improve positioning precision of the GPS/INS integrated navigation system during GPS outages, a novel model combined with strong tracking Kalman filter (STKF) and wavelet neural network (WNN) algorithms for INS errors compensation is proposed and tested. STKF is used to estimate INS errors as a replacement of Kalman filter (KF), and WNN is applied to establish a highly accurate model based on STKF when GPS works well and to predict INS errors during GPS outages. Performance of the proposed model has been experimentally verified using GPS and INS data collected in a land vehicle navigation test. The comparison results indicate that the proposed model combined with STKF/WNN algorithms can effectively provide high accurate corrections to the standalone INS during GPS outages.     

一种基于图优化的行人协同定位方法

基于手机惯性传感器的行人航位推算方法是行人导航的核心方法之一。 然而由于传感器噪声等因素,航位推算获取 的位置信息误差往往随着时间发散,通常将航位推算和卫星导航通过卡尔曼滤波构成组合导航系统,利用卫星提供的高精度定 位信息补偿航位推算误差。 提出一种基于图优化的行人协同定位方法,将状态转移、量测和协同测距信息都作为状态的约束, 统一进行优化估计。 为验证方法的有效性,分别在卫星信号良好、无卫星环境下进行了实验验证。 实验分析结果表明,基于图 优化的行人协同定位方法在有无卫星信号情况下,都可以有效地提升系统的定位精度。 和基于卡尔曼滤波的协同方法相比,最 大水平定位误差都减少了 30% 以上。     

基于多基站IMMKF-DOA辅助车辆协同定位算法研究

针对传统卡尔曼滤波算法在进行车辆实时运动过程中难以精准定位问题,提出一种基于运动状态自适应的交互多模型卡尔曼滤波(Interacting multiple model Kalman filter,IMMKF)与多基站到达方向(Direction-of-arrival,DOA)相融合进行车辆位置实时估计算法。基于无偏估计器对测量噪声协方差进行实时更新并将其嵌入标准卡尔曼滤波算法中实现自适应交互多模型卡尔曼滤波。针对车辆不同运动状态及动态行驶环境对车辆定位估计精度的影响,构建自适应交互多模型卡尔曼滤波器与多基站信息融合算法进行车辆位置实时估计,考虑不同车速与不同基站数等行驶工况下车辆定位精度的变化趋势,实现车辆实时位置的准确估计。利用PreScan-Simulink联合仿真平台进行虚拟仿真验证和实车试验验证。结果表明,基于交互多模型卡尔曼滤波与到达方向角的融合算法相对标准的卡尔曼滤波估计精度高,较好地改善了传统单一模型的卡尔曼滤波算法在进行车辆实时运动状态估计过程中精准定位问题,实车试验验证了提出算法对车辆定位精度较传统卡尔曼滤波算法的精度提高了一个数量级,实现了更精确的车辆位置估计。     

Ellipsoid bounding estimation for kinematic geodetic positioning

In kinematic position estimation, a Kalman filter procedure is often used to provide improved solution benefiting from the history information. However, the optimal Kalman filtering solutions are subject to precise function models and statistic knowledge of noises, which may be difficult to obtain in advance. As a result, Kalman filter does not necessarily provide better performance for kinematic positioning solutions. In real world situations, a bound of the noise distribution would be easily and more reasonably determined than noise statistics. This paper studies ellipsoid bounding estimation for kinematic position estimation. In this estimation, neither process nor measurement noise characteristics are necessary, as long as the noises at each sample points can be confined in a bound (ellipsoid). A general trace criteria is adopted to choose the optimal estimator. For a the special case that only scalar measurement is available, e.g., a position measurement, we designed a modified intersection approach to reduce the estimation conservatism. Numerical results are given in each estimation step to illustrate the algorithm. A flight trajectory data is processed and the estimation results are compared under three different measurement noise cases: Gaussian white noise, uniformly noise (non-Gaussian) and the real measurement noise. Kalman filter results are also given for comparison. Results demonstrate the ellipsoid estimation indeed offers improved kinematic position solution in the sense of robustness for non-Gaussian noises, and retains nearly the same estimation error variance.     

Practical constraints on real time Bayesian filtering for NDE applications

An experimental evaluation of Bayesian positional filtering algorithms applied to mobile robots for Non-Destructive Evaluation is presented using multiple positional sensing data – a real time, on-robot implementation of an Extended Kalman and Particle filter was used to control a robot performing representative raster scanning of a sample. Both absolute and relative positioning were employed – the absolute being an indoor acoustic GPS system that required careful calibration. The performance of the tracking algorithms are compared in terms of computational cost and the accuracy of trajectory estimates. It is demonstrated that for real time NDE scanning, the Extended Kalman Filter is a more sensible choice given the high computational overhead for the Particle filter.     

交互多模型在车辆组合定位系统中的应用（英文）

为解决扩展卡尔曼滤波器(extended Kalman filter,EKF)在车辆组合定位系统中因车辆加减速、转弯(以下简称机动)而存在的精度低、稳定性差等问题,设计了一种将交互多模型(interacting multiple model,IMM)算法与非线性卡尔曼滤波器相融合的自适应滤波算法。该算法使用三种状态空间模型来描述车辆的运动模式,采用多个非线性滤波器对每个模型并行滤波,通过模型匹配似然函数对滤波结果进行加权融合,最终得到系统的定位信息。该方法具备非线性系统滤波器优点,克服了单一模型滤波算法对机动目标定位效果差的缺点。利用该方法和EKF算法分别对GPS/INS/DR车辆组合定位系统中进行了仿真实验,结果表明,该算法的滤波定位精度明显优于目前组合定位系统中所用的EKF滤波器,大幅提高了组合定位系统的稳定性和定位精度。     

Outdoor position estimation based on a combination system of GPS-INS by using UPF

This paper proposes a technique that global positioning system(GPS)combines inertial navigation system(INS)by using unscented particle filter(UPF)to estimate the exact outdoor position.This system can make up for the weak point on position estimation by the merits of GPS and INS.In general,extended Kalman filter(EKF)has been widely used in order to combine GPS with INS.However,UPF can get the position more accurately and correctly than EKF when it is applied to real-system included non-linear,irregular distribution errors.In this paper,the accuracy of UPF is proved through the simulation experiment,using the virtual-data needed for the test.