姿态测量子系统外文翻译`.docVIP

毕业设计(论文)外文资料翻译 系 别： 电子信息系 专 业： 通信工程 班 级： B090310 姓 名： 贠鸽 学 号： 外文出处： 知网 附 件： 1. 原文； 2. 译文 2013年03月 Attitude Determination Subsystem Spacecraft attitude determination is the process of estimating the orientation of a spacecraft by making remote observations of other celestial bodies or reference points. Combinations of these sensor observations are used to generate a more accurate estimate of spacecraft rotational attitude. Attitude estimates must be calculated quickly and continuously during the entire operational life of the mission. During normal operations, the problem is recursive—the attitude filter basing new predictions on present and prior sensor information. The attitude filter must also estimate from activation when the spacecraft is first initiated and no prior data is available. Since spacecraft orientation will vary with time and task, orientation changes must be tracked, and rates and accelerative torques estimated. The systems designed to carry out 3-axis attitude determination are inevitably complex, but must still be designed with the utmost care to perform the task as reliably as possible. Any, even temporary malfunction is potentially serious, damaging fragile instruments, breaking communications links, upsetting measurements and disrupting power generation. 1.Conventional Systems Modern attitude systems carry a variety of different sensor instruments to cover the different modes of operation. Data processing is by a radiation-hardened computer of limited power and memory. Systems adopt a mode-oriented approach using different sensors and algorithms to derive attitude for each spacecraft activity. Changes between certain modes may occur automatically (particularly those associated with acquisition),