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改进粒子滤波与预测滤波相结合的单星敏姿态估计 总被引:1,自引:0,他引:1
针对卫星姿态估计的非线性、非高斯特性,提出一种粒子滤波和预测滤波相结合的估计方法,在无角速率测量时,首先利用预测方法在线估计系统模型误差和姿态角速度,再通过改进的规则化粒子滤波器估计姿态四元数.粒子初始化和重要性函数等的设计加快了算法的收敛速度,预测方法的引入有效降低了粒子维数.在某通用小卫星平台上进行仿真,并与扩展卡尔曼滤波(EKF)比较,所得结果表明,算法在不同初始姿态估计时具有较好的稳定性和收敛精度.算法还为粒子滤波和无陀螺定姿的研究提供了参考. 相似文献
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为研究无陀螺卫星控制优化问题的新方法,针对环境干扰力矩和估计误差等不确定因素导致滤波器稳定性和估计精度降低,提出了使用星敏感器测量值在线估计模型参数和卫星姿态的非线性预测滤波方法.根据预测滤波理论推导了关于模型误差的损失函数,利用线性化的测量方程求得使损失函数最小化的模型误差值,代人状态方程求数值积分,得到卫星的姿态估计参数.仿真结果证明,不仅简化了计算,且适应性更强.而应用四元数描述卫星姿态,避免了欧拉角法的奇异性问题.仿真结果还表明,方法收敛速度较EKF更快,状态估计精度与EKF相当,并对非线性模型误差具有良好的跟踪性能. 相似文献
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针对动态系统目标跟踪问题,RBPF算法通过将高维状态空间分解成易于处理的线性子部分与非线性子部分,并采取不同策略进行滤波估计。为了提高RBPF的计算效率,提出将粒子群优化思想融入到RBPF滤波估计中,凭借粒子群算法卓越的全局搜索能力,对于状态空间中非线性部分,通过粒子群算法驱使所有采样粒子向高似然区域(最优适应值区域)移动;对于线性状态部分,依然利用卡尔曼滤波进行处理。通过多组实验仿真结果对比,PSO-RBPF利用较少采样粒子、耗费较少时间即能获得极佳的估计精度。 相似文献
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针对非线性工业过程测量的滞后性和模型不确定性给系统状态估计和模型参数估计造成的困难,在扩展Kalman滤波器(EKF)的基础上,引入有限差分滤波器(FDEKF)和次优渐消因子,提出了一种强跟踪有限差分滤波状态和参数二元估计算法。该二元估计算法将滤波器分解为参数滤波和状态滤波两个过程,分别估计模型参数和系统状态。最后,将该算法应用于一化学反应过程的仿真,结果表明,这种强跟踪有限差分滤波的二元估计算法在原模型或参数存在偏差的情况下,仍能较准确地估计系统状态和模型参数,并具有较强的数值鲁棒性。 相似文献
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姿态确定算法是卫星姿态确定系统的重要组成部分。在姿态确定系统中广泛采用卡尔曼滤波作为姿态确定算法,但是卡尔曼滤波依赖于噪声统计特性的先验知识,采用不精确的噪声统计特性设计卡尔曼滤波器可能会导致较大的估计误差,甚至造成滤波发散。本文针对噪声统计特性的不确定性分别采用了自适应卡尔曼滤波器和预测滤波器估计卫星姿态,通过数学仿真验证在噪声统计特性不确定的情况下。这两种滤波器仍然可以较精确地估计卫星姿态。 相似文献
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为了提高中心差分卡尔曼粒子滤波(CDKFPF)算法跟踪时的估计精度,提出了一种基于迭代测量更新CDKF的粒子滤波(ICDKFPF)新算法。该算法利用迭代中心差分卡尔曼滤波的最大后验概率估计产生粒子滤波的重要性密度函数,并用Levenberg-Marquardt方法对状态协方差进行修正,使粒子的观测信息得到充分有效的利用,更加符合真实状态的后验概率分布。仿真结果表明,所提出算法的估计性能要明显优于标准的粒子滤波(PF)和中心差分卡尔曼粒子滤波(CDKFPF)。 相似文献
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An algorithm based on the marginalized particle filters (MPF) is given in details in this paper
to solve the spacecraft attitude estimation problem: attitude and gyro bias estimation using the
biased gyro and vector observations. In this algorithm, by marginalizing out the state appearing
linearly in the spacecraft model, the Kalman filter is associated with each particle in order to
reduce the size of the state space and computational burden. The distribution of attitude vector
is approximated by a set of particles and estimated using particle filter, while the estimation of
gyro bias is obtained for each one of the attitude particles by applying the Kalman filter.
The efficiency of this modified MPF estimator is verified through numerical simulation of a fully
actuated rigid body. For comparison, unscented Kalman filter (UKF) is also used to gauge the
performance of MPF. The results presented in this paper clearly demonstrate that the MPF is superior
to UKF in coping with the nonlinear model. 相似文献
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An algorithm based on the marginalized particle filters (MPF) is given in details in this paper to solve the spacecraft attitude estimation problem: attitude and gyro bias estimation using the biased gyro and vector observations. In this algorithm, by marginalizing out the state appearing linearly in the spacecraft model, the Kalman filter is associated with each particle in order to reduce the size of the state space and computational burden. The distribution of attitude vector is approximated by a set of particles and estimated using particle filter, while the estimation of gyro bias is obtained for each one of the attitude particles by applying the Kalman filter. The efficiency of this modified MPF estimator is verified through numerical simulation of a fully actuated rigid body. For comparison, unscented Kalman filter (UKF) is also used to gauge the performance of MPE The results presented in this paper clearly derfionstrate that the MPF is superior to UKF in coping with the nonlinear model. 相似文献
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针对难以配置高精度部件的皮纳卫星姿态测量系统,当卫星处于阴影区或任何太阳敏感器不可用的状态下,MEMS陀螺与磁强计的组合便成为卫星在轨姿态测量精度的重要保障.本文基于MEMS陀螺与磁强计的低功耗、全轨、全天时、最小姿态敏感组合,提出一种适用于皮纳卫星在轨运行的滤波系统方案.该方案通过滑窗ARMA建模降低陀螺随机噪声的影响,并由姿态滤波器估计所得的零偏在线去除陀螺常值分量,以保证其建模的长期有效性.本文以浙江大学皮星二号卫星搭载的敏感部件以及姿态测量算法为研究基础,结合在轨实测数据,仿真对比表明,该系统方案有效降低了陀螺随机噪声,抑制比达50%以上;陀螺零偏估计精度提高310%,可达到0.001°/s;姿态确定精度提升190%,可达1.2127°.该系统方案是对皮纳卫星姿态确定最小系统精度提升及实用方案设计的有益探索. 相似文献
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In this paper an unscented Kalman filter based procedure for the bias estimation of both the magnetometers and the gyros carried onboard a pico satellite, is proposed. At the initial phase, biases of three orthogonally located magnetometers are estimated as well as the attitude and attitude rates of the satellite. During the initial period after the orbit injection, gyro measurements are accepted as bias free since the precise gyros are working accurately and the accumulated gyro biases are negligible. At the second phase estimated constant magnetometer bias components are taken into account and the algorithm is run for the estimation of the gyro biases that are cumulatively increased by time. As a result, six different bias terms for two different sensors are obtained in two stages, where attitude and attitude rates are estimated regularly. For both estimation phases of the procedure an unscented Kalman filter is used as the estimation algorithm. Copyright © 2011 John Wiley and Sons Asia Pte Ltd and Chinese Automatic Control Society 相似文献
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In recent years particle filters have been applied to a variety of state estimation problems. A particle filter is a sequential Monte Carlo Bayesian estimator of the posterior density of the state using weighted particles. The efficiency and accuracy of the filter depend mostly on the number of particles used in the estimation and on the propagation function used to re-allocate weights to these particles at each iteration. If the imprecision, i.e. bias and noise, in the available information is high, the number of particles needs to be very large in order to obtain good performances. This may give rise to complexity problems for a real-time implementation. This kind of imprecision can easily be represented by interval data if the maximum error is known. Handling interval data is a new approach successfully applied to different real applications. In this paper, we propose an extension of the particle filter algorithm able to handle interval data and using interval analysis and constraint satisfaction techniques. In standard particle filtering, particles are punctual states associated with weights whose likelihoods are defined by a statistical model of the observation error. In the box particle filter, particles are boxes associated with weights whose likelihood is defined by a bounded model of the observation error. Experiments using actual data for global localization of a vehicle show the usefulness and the efficiency of the proposed approach. 相似文献
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Jun Kyu Lim Kwang Rok Choi Chan Gook Park 《International Journal of Control, Automation and Systems》2012,10(5):1070-1076
The aim of this paper is to improve state estimation and FDI performance. We proposed an algorithm using a model based multi-hypothesis filter (MHF). With this method, we can detect and identify the fault on a satellite actuator. Also, we can improve the attitude estimation performance of a satellite attitude control system. In this method, there are several models for a possible failure situation and the model probabilities are decided from the residuals of each filter. The master filter finds the most suitable state estimation result from the weighting sum of each filter based on probabilities. And a probability crossing detection algorithm and thresholding algorithm based on probabilities are introduced for fault detection and identification of satellite actuators. The simulation results demonstrate the advantages of the MHF-based method proposed. 相似文献
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目前扩展目标跟踪算法大都假设其系统为线性高斯系统,针对非线性系统的多扩展目标跟踪问题,提出了采用粒子滤波技术对目标状态和关联假设进行联合估计的多扩展目标跟踪算法。首先,提出了将多扩展目标状态和关联假设进行联合估计的思想,解决了在估计目标状态和数据关联时相互牵制的问题;其次,根据扩展目标演化模型、量测模型建立多扩展目标状态和关联假设的联合建议分布函数,并利用粒子滤波技术实现联合估计的Bayes框架;最后,为解决直接采用粒子滤波实现时存在的维数灾难问题,将目标联合状态粒子的产生和演化分解为各个目标状态粒子的产生和演化,对每个目标的粒子集根据与其相关的权重单独进行重抽样,这样在抑制目标状态估计较差部分的同时使每个目标都保留了对其状态估计较好的粒子。仿真实验结果表明,与扩展目标概率假设密度滤波器的高斯混合实现方式和序贯蒙特卡洛实现方式相比,所提算法的状态估计精度较高,形状估计的Jaccard距离分别降低了30%、20%左右,更适合于非线性系统的多扩展目标跟踪。 相似文献