排序方式: 共有55条查询结果,搜索用时 15 毫秒
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介绍了一个由工业控制机和智能测量仪器组成的自动化检定系统,采用定角测时法,利用高精度光学棱体和激光测角技术,实现了对高精度低速回转台的自动化检定。阐述了自动化检定系统的组成、转速检定原理、软件设计和数据处理方法,并给出了实际应用的结果。 相似文献
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收敛转弯是目前国外普遍采用的试飞驾驶方法,通过与以往采用的试飞驾驶方法进行比较,说明收敛转弯方法的优越性,并阐述了收敛转弯的操纵要领,注意事项,安全措施及其适用范围。理论和实践证明,收敛转弯是一种较好的试飞驾驶方法,在试飞中有广泛的用途,值得推广。 相似文献
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《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2023,71(3):1769-1783
Lunar final approach navigation is critical for pin-point lunar landing in future missions. This study investigates the use of lunar gravity gradient measurements for autonomous navigation of a lunar probe during the final approach phase. As the spacecraft approaches the Moon, the strength of gravity gradient signals improves. A spaceborne gravity gradiometer can precisely measure local gravity gradients, and the latest lunar gravity model GL1500E is used to provide reference values. The employed truncation degree and order of the gravity model are increased stepwise considering the decreasing altitude of the spacecraft in order to reach a compromise between computational costs and model accuracy. An iterative Kalman filter is developed for coupled orbit and attitude estimation using gravity gradient measurements and attitude quaternions obtained from star sensors. A simulated spacecraft with a gradiometer noise level of 0.01 E is considered. Simulation results show that the spacecraft’s position converges rapidly and achieves an accuracy of less than 100 m at the last epoch. 相似文献