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Hang Guo Min Yu Chengwu Zou Wenwen Huang 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2010
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. 相似文献
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James R. Drummond Jiansheng Zou Florian Nichitiu Jayanta Kar Robert Deschambaut John Hackett 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2010
The MOPITT (Measurements of Pollution in the Troposphere) instrument has provided more than nine years of global carbon monoxide (CO) measurements on a continuous basis since its launch aboard the Terra Spacecraft on December 18th, 1999. This paper gives an overview of the core sub-system performance and major issues of the in-flight instrument over the mission period. Some of the instrument anomalies are also discussed. The major successes are: (1) the concept of using a combination of correlation systems such as Length Modulated Cells (LMCs) and Pressure Modulated Cells (PMCs) to retrieve CO profiles in the troposphere; (2) the redundant design in the instrumentation which was crucial for coping with unexpected in-flight anomalies and for continuing the mission in the case of component failure; (3) the thermal environment on orbit that is so stable that some calibration procedures are not necessary; and (4) the recent production of CO total column retrieved from the MOPITT 2.3 μm channel. 相似文献
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二级倒立摆是一种典型的非线性不稳定系统,被广泛用于研究和验证各种控制方法。基于H∞理论控制方法的特点是鲁棒性很强,以尝试采用基于H∞理论控制方法对二级倒立摆进行运动控制,经过仿真实验证明,该控制方法可行并且有效。 相似文献
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介绍一种国内最新的智能测压系统,这是一个模块化、小型化的电子压力自动扫描系统。它包括电子扫描阀、工作传感器组合、标准传感器、自动校准单元、放大电路、A/D转换、采样接口及单片微机系统。用它可以实现多点压力的实时数据采集与处理、实时对传感器的零点(Z)、工作点(O)、及标准点(C)等状态进行自动转换,并实时地对传感器的零点、灵敏度、线性度、温漂、时漂等误差进行自动补偿与修正。 对该系统的原理、结构特点及实验结果分析进行了简要叙述。这种系统测量精度高、自动化程度高,特别适用于航空发动机试车台及风洞试验中的压力测量与处理。 相似文献
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