共查询到19条相似文献,搜索用时 187 毫秒
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一种鲁棒Sigma-point滤波算法及其在相对导航中的应用 总被引:2,自引:0,他引:2
研究了一种鲁棒Sigma-point滤波方法在无人机编队相对导航问题上的应用。该方法采用Huber估计方法,将Sigma-point滤波量测更新转化为求解线性回归问题,新的Sigma-point滤波方法是一种混合L1、L2范数最小估计,当量测噪声为受污染的高斯白噪声时,该方法具有一定的鲁棒性。给出了编队无人机相对惯导方程和相对视线矢量测量原理,应用鲁棒Sigma-point滤波方法融合相对惯导信息和相对视线矢量信息,估计出无人机之间的相对姿态、相对速度和相对位置。仿真结果表明,与扩展卡尔曼滤波和常规Sigma-point滤波相比,鲁棒Sigma-point滤波可以获得更高的估计精度。 相似文献
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针对非合作目标相对导航问题,为提高相对导航的精度和可靠性,采用双目视觉测量方法实现追踪器与目标器之间相对状态的测量,并基于鲁棒扩展卡尔曼滤波方法,提出了一种鲁棒相对导航滤波方法。仿真结果表明,该方法对相对导航系统模型中的不确定性具有良好的鲁棒性,且滤波精度较高。 相似文献
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提出了一种离散系统的优化鲁棒滤波方法。为了得到滤波的逼近计算式,通过优化加权矩阵得到了上界不等式逼近和等效系统矩阵,得到了鲁棒滤波的时间更新算法;通过优化加权矩阵得到了下界不等式逼近和等效观测矩阵,得到了鲁棒滤波的测量更新算珐,并且给出了鲁棒滤波算法收敛的条件。飞行试验数据处理的结果表明,提出的方法是有效的。 相似文献
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采用微小卫星姿态运动学、动力学方程,以磁强计/太阳敏感器为姿态敏感器进行姿态确定,研究了一种基于融合反馈的改进联邦滤波算法,提出了一种基于观测新息修改的信息分配原则。给出了由四元数描述卫星姿态的误差状态方程,并对观测矢量进行推导,获得了基于角速度的观测方程,丰富了观测模型。仿真结果表明:基于角速度观测方程的引入,增强了观测信息的利用率,进而提高了姿态确定的精度,降低了计算量,保证了可靠性。 相似文献
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针对存在建模误差及测量噪声干扰条件下的涡扇发动机性能参数估计问题,标准卡尔曼滤波及其改进算法滤波估计误差收敛速度慢,滤波估计精度低,对不确定测量噪声及建模误差较为敏感,为此本文提出了一种变参数鲁棒H_∞滤波器设计方法。该方法采用仿射参数依赖Lyapunov函数设计满足H_∞性能指标要求的鲁棒滤波器,通过引入凸多胞技术,将参数依赖线性矩阵不等式(Linear Matrix Inequality,LMI)中变参数Lyapunov矩阵与系统系数矩阵之间耦合乘积导致的非凸优化问题,转化为常规LMI约束下的凸优化问题进行求解,降低了线性变参数(Linear Parameter Varying,LPV)鲁棒滤波器设计的保守性,得到了全局解。针对涡扇发动机的仿真结果表明:与扩展卡尔曼滤波器对比,采用该方法设计的滤波器具有较快的动态跟踪速度和较高的滤波精度,ΔFn的稳态估计误差不大于0.1%,ΔFn的相对估计误差不大于2.5%,同时对建模误差和测量噪声干扰具有较强的抑制能力。 相似文献
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This article presents a near-Earth satellite orbit estimation method for pico-satellite applications with light-weight and low-power requirements. The method provides orbit information autonomously from magnetometer and sun sensor, with an extended Kalman filter (EKF). Real-time position/velocity parameters are estimated with attitude independently from two quantities: the measured magnitude of the Earth’s magnetic field, and the measured dot product of the magnetic field vector and the sun vector. To guarantee the filter’s effectiveness, it is recommended that the sun sensor should at least have the same level of accuracy as magnetometer. Furthermore, to reduce filter’s computation expense, simplification methods in EKF’s Jacobian calculations are introduced and testified, and a polynomial model for fast magnetic field calculation is developed. With these methods, 50% of the computation expense in dynamic model propagation and 80% of the computation burden in measurement model calculation can be reduced. Tested with simulation data and compared with original magnetometer-only methods, filter achieves faster convergence and higher accuracy by 75% and 30% respectively, and the suggested simplification methods are proved to be harmless to filter’s estimation performance. 相似文献
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针对低轨微纳卫星体积小、功耗低的设计约束,提出了基于低轨地磁的定轨/定姿全磁自主导航算法.该算法仅利用三轴磁强计测量值和卫星动力学方程建立Kalman滤波器,实现了低轨微纳卫星的全自主轨道确定和姿态测量,理论仿真结果表明,该全磁导航算法精度能够满足低轨微纳卫星的一般要求.利用高精度地磁模拟器搭建了微纳卫星全磁自主导航地面仿真验证系统,对算法进行了全物理仿真测试和实验误差分析,进一步验证了全磁自主导航算法的可行性,为低轨微纳卫星提供了一种低成本、高自主、高可靠性的导航方法. 相似文献
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A Cubesat mission with a deployable solar sail of 5 meter by 5 meter in a sun-synchronous low earth orbit is analyzed to demonstrate solar sailing using active attitude stabilization of the sail panel. The sail panel is kept parallel to the orbital plane to minimize aerodynamic drag and optimize the orbit inclination change caused by the solar pressure force normal to the sail surface. A practical control system is proposed, using a combination of small 2-dimensional translation of the sail panel and 3-axis magnetic torquing which is proved to have sufficient control authority over the gravity gradient and aerodynamic disturbance torques. Miniaturized CMOS cameras are used as sun and nadir vector attitude sensors and a robust Kalman filter is used to accurately estimate the inertially referenced body rates from only the sun vector measurements. It is shown through realistic simulation tests that the proposed control system, although inactive during eclipse, will be able to stabilize the sail panel to within ±2° in all attitude angles during the sunlit part of the orbit, when solar sailing is possible. 相似文献
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Based on magnetometer measurements only, three-axis attitude, rate, and orbit estimation are successfully achieved. A single Augmented Dynamics Extended Kalman Filter (ADEKF) is configured by combining the spacecraft nonlinear attitude dynamics and quaternion kinematics with orbital mechanics. The filter design is adopted for three-axis stabilized spacecraft in low Earth orbits where the aerodynamic drag is the dominant source of disturbances in addition to the spacecraft magnetic residuals. To reduce the computational burden, another Interlaced Extended Kalman Filter (IEKF) is developed to uncouple the attitude/rate from the orbit dynamics. Both filters are implemented using the magnetometer measurements and their corresponding time derivatives. As a part of EgyptSat-1 flight scenario, detumbling and standby modes are used for performance testing of the ADEKF. The concept of local observability is applied to the basic filter and the stability is investigated by incorporating extensive Monte Carlo simulations with uniformly distributed initial conditions. The filter shows the capability of estimating the attitude better than 5 deg and rate of order 0.03 deg/s in each axis. In orbit estimation, the filter is capable of estimating the position with accuracy less than 8 km and velocity upto 5 m/s in each axis. 相似文献
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采用高精度卫星导航速度、位置信息以及星敏感器提供的姿态信息设计十表冗余捷联惯组的标定模型,包含陀螺和加速度计的零次项和标度因数,对卫星和星敏感器辅助的冗余激光陀螺捷联惯组进行实时在轨标定.利用标准Kalman滤波和Sage-Husa自适应滤波作为估计算法,对十表冗余捷联惯组参数进行在线估计.数值仿真结果表明:参数标定精度均在7%以内,是一种实时的在轨标定方法,满足误差补偿要求.冗余惯组在轨标定方法为航天器高精度定姿和定轨提供了一种理论参考. 相似文献
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In order to determine an appropriate attitude of three-axis stabilized communication satellites, this paper describes a novel attitude determination method using direction of arrival (DOA) estimation of a ground signal source. It differs from optical measurement, magnetic field measurement, inertial measurement, and global positioning system (GPS) attitude determination. The proposed method is characterized by taking the ground signal source as the attitude reference and acquiring attitude information from DOA estimation. Firstly, an attitude measurement equation with DOA estimation is derived in detail. Then, the error of the measurement equation is analyzed. Finally, an attitude determination algorithm is presented using a dynamic model, the attitude measurement equation, and measurement errors. A developing low Earth orbit (LEO) satellite which tests mobile communication technology with smart antennas can be stabilized in three axes by corporately using a magnetometer, reaction wheels, and three-axis magnetorquer rods. Based on the communication satellite, simulation results demonstrate the effectiveness of the method. The method could be a backup of attitude determination to prevent a system failure on the satellite. Its precision depends on the number of snapshots and the input signal-to-noise ratio (SNR) with DOA estimation. 相似文献
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微小型无人机用微磁数字罗盘集成系统的设计 总被引:4,自引:1,他引:3
针对现有微磁数字罗盘成本高、输出频率低、动态定姿时易发散等问题,结合微小型无人机(MUAV)导航与控制系统的组成特点,设计了一种利用MUAV机载微惯性测量单元(MIMU)中的天向陀螺输出判断无人机的运动状态,采用MIMU中的3轴加速度计组件测量的地球重力矢量,配合3轴磁阻传感器测量的地球磁场矢量,共同进行姿态确定的微磁数字罗盘集成系统。对传统的环境干扰磁场校正方法进行了完善与验证,使之适合于空间三维定姿。试验结果表明:系统总体性能良好,航向精度可达0.5°,成本为同类产品的1/5,输出响应可达50 Hz,满足应用于MUAV导航控制系统的微磁数字罗盘的高精度、低成本和实时性的要求。 相似文献