一类抗冲击载荷的新型橡胶减振器

针对某惯测装置冲击环境恶劣的问题,采用理论分析和有限元模拟相结合的方法,研制了能同时兼顾缓冲和阻尼减振的减振器.试验表明,研制的新型橡胶减振器使惯性测量装置的冲击响应由100 g下降到30.3 g,同时兼有阻尼减振效果.     

Kalman filtering for GPS/magnetometer integrated navigation system

This paper investigated the data processing method for a GPS/IMU/magnetometer integrated system with Kalman filtering (KF). As a result of GPS/IMU/magnetometer land vehicle system, dead-reckoning of magnetometer and accelerometer integrated subsystem bridged very well the GPS signal outage due to the trees on the two sides of the road. Both differential GPS data processing method and the carrier-phase method with magnetometers’ outputs for predicting the car position, velocity, and acceleration (PVA) are presented. The results from DGPS with Kinematical Positioning (KINPOS) software shown that the averages of the north, east, and down direction standard deviation (short for “std”) are 0.014, 0.010, and 0.018 m, respectively. The std of velocities and accelerations derived by the position and velocity differentiation are 10, 7, 13 mm/s, 7, 5, 9 mm/s², respectively. This method for getting velocities and accelerations requires higher accurate position coordinates. But the position accuracy has frequently been degraded in this case when the car drove under the trees or other similar kinematical environments. That caused the larger velocity and acceleration errors. While the results from the carrier-phase method are std of the velocities = 2.1 mm/s, 1.3 mm/s, 3.7 mm/s in north, east, down, and std of the accelerations = 1.5 mm/s², 0.9 mm/s², 2.3 mm/s² for the static test period; as compared with KINPOS software results, std of the velocity difference between the carrier-phase method and the DGPS method = 7 mm/s, 6.9 mm/s, 9.7 mm/s in north, east, down direction, and std of acceleration difference = 5.0 mm/s², 4.5 mm/s², 7.5 mm/s² in north, east, down direction for the kinematical test period. Obviously, errors come from both the carrier-phase method and DGPS velocity and acceleration results derived directly by the position differentiation. In addition, better accuracy of positions than that before KF has been got by means of velocities and accelerations derived by the carrier-phase method after KF.     

激光陀螺捷联惯导系统旋转调制技术综述

激光陀螺旋转调制技术是一种系统级误差自补偿技术，能够有效调制陀螺和加速度计的误差，提高导航系统的精度。首先分析了旋转调制型捷联惯导系统的基本原理和类型，然后从转位方案的编排、惯性测量单元旋转速度和转停时间的选取、旋转机构的导航解算、旋转机构的误差分析、载体角运动隔离等多方面，对激光陀螺旋转调制技术进行了综述，并探讨了我国旋转调制技术的重点研究方向，提出了合理的建议。     

晃动基座初始对准环境建模与仿真

针对火箭初始对准时存在外界扰动,提出一种适用于风扰动的初始对准环境建模与仿真方法,可用于运载火箭扰动环境下初始对准仿真验证.根据风场特性和振动理论,分别建立了地面风和风干扰下的箭体振动模型,实现了晃动基座下的环境仿真和对捷联惯组测量输出的模拟.仿真结果显示,箭体振动特性与实测值一致,所模拟的惯组输出与箭体晃动吻合,表明模型正确有效.该方法能够为晃动环境下初始对准仿真研究提供更加符合实际特性的数据源.     

带FDI算法的无人机组合导航姿态确定控制系统设计

无人机导航系统的作用是提供导航数据给飞控计算机作为制导和控制用,因为飞控计算机的性能在很大程度上依赖于导航数据,导航系统的某一个错误可能会导致整个无人机的失败,因此,导航系统应具有故障检测和隔离(FDI)算法,介绍了一种用于无人机导航的FDI和低成本的组合导航系统,硬件包括低成本商业用MEMSIMU、GPS接收器、磁力计和导航计算机,软件包括带FDI算法的卡尔曼滤波。     

惯性组合误差射前等效补偿方法研究

为了解决原有的惯性组合工具误差有修正的不能准确分离加速度计零次项与一次项的缺点，在分析弹道特性和工具误差被偿模型的基础上，提出了加速度计误差射前等效补偿方法，实现了在导弹临射前对纵向加速度计零次项和一次顶误差的等效补偿。     

一种改进的IMU加表标定模型及快速标定方法

针对MEMS产品工程应用的需求,提出了一种改进的IMU加表标定模型,更清晰地分离出与安装误差有关的投影关系阵以及与器件误差有关的刻度转化阵。并且,在此模型的基础上给出了不需转台的快速标定方法。投影关系阵不变,该方法减少了观测量,只需6位置来估计加速度计的零位和标度因数,同时进行了现场误差补偿。     

Radiation testing of a commercial 6-axis MEMS inertial navigation unit at ENEA Frascati proton linear accelerator

We present the first results of a novel collaboration activity between ENEA Frascati Particle Accelerator Laboratory and University La Sapienza Guidance and Navigation Laboratory in the field of Radiation Hardness Assurance (RHA) for space applications.The aim of this research is twofold: (a) demonstrating the possibility to use the TOP-IMPLART proton accelerator for radiation hardness assurance testing, developing ad hoc dosimetric and operational procedures for RHA irradiations; (b) investigating system level radiation testing strategies for Commercial Off The Shelf (COTS) components of interest for SmallSats space missions, with focus on devices and sensors of interest for guidance, navigation and control, through simultaneous exploration of Total Ionizing Dose (TID), Displacement Damage (DD) dose and Single-Event Effects (SEE) with proton beams.A commercial 6-axis integrated Micro Electro-Mechanical Systems (MEMS) inertial navigation system (accelerometer, gyroscope) was selected as first Device Under Test (DUT). The results of experimental tests aimed to define an operational procedure and the characterization of radiation effects on the component are reported, highlighting the consequence of the device performance degradation in terms of the overall navigation system accuracy. Doses up to 50 krad(Si) were probed and cross sections for Single-Event Functional Interrupt (SEFI) evaluated at a proton energy of 30 MeV.     

激光捷联惯导减振系统设计与应用

针对激光陀螺捷联惯导系统在地面动态导航测试中圆概率误差偏大的现象,要求给激光陀螺捷联惯导系统设计出性能优良的减振系统。分析激光惯导的振动模型,结合对比原有惯导减振系统提出双层减振。在对双层减振系统的分析中,把整个安装支架作为减振系统的一部分,充分考虑弹载设备的可安装性,应用有限元法设计出动态性能良好的安装支架和减振器来改善减振效果。通过地面大量振动试验的验证以及反复对支架和减振器参数的优化设计,使得新构建的减振系统的谐振频率避开激光陀螺的机抖频率以及其它需要减振的频率段,减振效果达到了预期的设计要求,可以在飞行器上使用。     

用真实IMU/GPS数据进行机载SAR运动补偿处理

分析了机载SAR(Synthetic Aperture Radar)条带成像模式的运动补偿技术原理,通过对激光IMU/GPS(Inertial Measurement Units/Global Positioning System)组合提供的位置参数进行分析,表明Y12载机平台具有很大的运动误差,在此基础上利用高精度激光IMU/GPS组合提供的天线相位中心精确位置参数,结合距离-多普勒成像算法进行了机载SAR数据的运动补偿处理,试验表明利用此IMU/GPS提供的运动参数进行对具有很大运动误差的SAR数据运动补偿后,已不需要计算负担沉重的自聚焦类算法进行残留运动误差补偿,就能得到高质量的高分辨率SAR图像.