Accession Number:

AD0759294

Title:

Unobservability in Attitude Estimation.

Descriptive Note:

Technical operating rept.,

Corporate Author:

AEROSPACE CORP EL SEGUNDO CALIF ENGINEERING SCIENCE OPERATIONS

Personal Author(s):

Report Date:

1971-03-16

Pagination or Media Count:

34.0

Abstract:

The report presents a general condition under which certain perturbation variables involved in spacecraft attitude estimation become unobservable. The attitude estimation system considered here is assumed to include a three-axis gyro package which senses attitude rate and a star sensor which provides discrete attitude measurements. The equations of motion are linearized about a nominal spacecraft attitude not necessarily the gyro-measured attitude reference. The linearized equations involve 12 perturbation quantities which are considered independent state variables to be estimated from measurements provided by the star sensor. The perturbation quantities include attitude errors, gyro bias and scale factor errors, and star sensor misalignment errors. Author Modified Abstract

Subject Categories:

  • Unmanned Spacecraft

Distribution Statement:

APPROVED FOR PUBLIC RELEASE