Patent ID: 6108593
Filing Date: 2000-08-22
Classification: B64G

Abstract:
A spacecraft attitude sensor error correction apparatus comprising:an attitude sensor that generates attitude-related position information based on a position of said attitude sensor with respect to a reference object, wherein said attitude-related position information contains a measurement error;an attitude reference source that generates reference position information regarding a position of said reference object with respect to a reference coordinate system based on temporal information;a spacecraft control processor that receives said attitude-related position information, along with said reference position information, and generates a measurement error estimate of said measurement error present in said attitude-related position information, and said spacecraft control processor using said measurement error estimates to null said measurement error present in said attitude-related position information;a bias correction block that receives said attitude-related position information from said attitude sensor and said measurement error estimate, and generates a difference signal representative of said difference between said attitude-related position information and said measurement error estimate;a measurement processing block that receives said reference position information and said difference signal and generates a spacecraft attitude estimate and measurement residuals; anda bias estimation block that receives said difference signal and said measurement residuals and generates said measurement error estimate that is used by said bias correction block.