Multiple star sensor timing sequence synchronization processing method based on time division multiplexing

Abstract

The invention provides a multiple star sensor timing sequence synchronization processing method based on time division multiplexing. The multiple star sensor timing sequence synchronization processing method includes the steps of controlling relationship between attitude and orbit control system control cycle and star sensor image processing cycle, on one hand, finishing read and write synchronization operations between a satellite attitude and orbit control system and a plurality of star sensors through designing of a time operation sequence based on the control cycle, and on the other hand, switching over data updating rate of the star sensors used in the attitude and orbit control system according to needs through the time sequence arrangement. Therefore, the multiple star sensor timing sequence synchronization processing method can periodically finish data acquisition and sending of instructions for all star sensors on the premise of ensuring normal mode control links, and can ensure that the star sensor data can be updated in every circle and can be used in attitude determining calculation according to a mode with attitude high precision requirements (generally is a station keeping mode), meets the requirements for star sensor data update rate in different modes of the attitude and orbit control system, and ensures attitude determining accuracy of the satellite attitude and orbit control system to a certain extent.

Description

technical field [0001] The invention relates to a control method of a star sensor, in particular to a star sensor data collection and synchronous processing method which can be applied to high-orbit satellites with a short control period. Background technique [0002] The star sensor is currently the most accurate attitude measurement component in satellite applications. It can be directly applied to attitude calculation, and can also be used for calibration of inertial measurement components (such as gyroscopes). In order to ensure the availability of star sensor data, generally 2 to 3 star sensors are installed in the satellite attitude and orbit control system. The external interface of the star sensor is RS422 interface, and the built-in ASIC chip of the computer of the attitude and orbit control system communicates with each star sensor. The application software of the attitude control system reads the data of the star sensor through the ASIC chip, forwards the operati...

AI Technical Summary

Problems solved by technology

However, it cannot be realized for high-orbit satellites. Within the control period of high-orbit satellites, the star sensor cannot complete a period of calculation. Therefore, high-orbit satellites cannot continuously obtain the effective attitude of the star sensor, which requires high attitude accuracy. As far as the system is concerned, the following problems are brought about:

[0004] (1) The attitude data of the star sensor is the data used periodically by the satellite attitude and orbit control system. In addition to the state data of other star sensors, the required transmission time is long. It is unrealistic to use the traditional waiting communication method, and it is possible Cause task overtime; at the same time, multiple star sensors share the ASIC chip, and only a single star sensor can communicate with the ASIC chip within a fixed period of time. Due to the large amount of data of the star sensor, this also makes it impossible to complete the communication with the star sensor within a single control cycle. Communication of multiple star sensors;

[0005] (2) In order to use the star sensor normally, it is necessary to send relevant instructions to the star sensor from time to time. The sending of the command also needs to be completed through the ASIC chip. Simultaneous reading and writing of serial ports

Under normal circumstances, the update time of the star sensor data is allowed to be a fixed period. In special modes (such as high-precision control modes such as position protection mode), it is required that the updated star sensor data participate in the attitude calculation in each control cycle. It will cause high-orbit satellites to be unable to retrieve the data of all star sensors at one time in the same cycle when processing star sensor data, especially for special control modes, which will affect the accuracy of attitude determination

At the same time, the reading and writing of star sensor data in different modes requires different timing. The mode switching process needs to coordinate the connection between the two types of timing, which also increases the difficulty of star sensor operation.

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