SELF-CONTAINED ONBOARD CONTROL SYSTEM OF "GASAD-2A" SPACECRAFT Russian patent published in 2007 - IPC B64G1/24 B64G1/28 B64G1/26 

FIELD: astro-navigation, control of attitude and orbital position of spacecraft.

SUBSTANCE: proposed system includes control computer, star sensor, Earth sensor, storage and timing device, processors for control of attitude, processing angular and orbital data, inertial flywheels and spacecraft orbit correction engine plant. Used as astro-orienters are reference and navigational stars from celestial pole zone. Direction of spacecraft to reference star and direction of central axis of Earth sensor to Earth center are matched with plane formed by central axes of sensors with the aid of onboard units. Shift of direction to reference star relative to central axis of Earth sensor is considered to be latitude change in orbital position of spacecraft. Turn of navigational star around reference star read off sensor base is considered to be inertial longitude change. Point of reading of longitude is point of spring equinox point whose hour angle is synchronized with the board time. This time is zeroed upon completion of Earth revolution. Stochastic measurements by means of static processing are smoothed-out and are converted into geographic latitude and longitude parameters. Smoothed inertial parameters are compared with parameters of preset turn of spacecraft orbit found in storage. Revealed deviations of orbit are eliminated by means of correction engine plant.

EFFECT: enhanced accuracy of determination of spacecraft attitude and orbital position; automatic elimination of deviation from orbit.

44 dwg