The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Aug. 27, 1991
Filed:
Aug. 11, 1989
James R Huddle, Chatsworth, CA (US);
Litton Systems, Inc., Beverly Hills, CA (US);
Abstract
A navigation method and apparatus for reducing substantially the measurement errors such as accelerometer bias, gyro drift rate, gyro scale factor errors, and gyro sensing axis orientation uncertainty. The navigation apparatus includes a first gimbal for rotating a triad of gyroscopes and accelerometers about a first gimbal axis at a predetermined angular rate. The axis is positioned in a plane whose orientation is fixed in inertial space (as, for example, parallel to the earth's equatorial plane). The direction of rotation about the first gimbal axis is periodically reversed. A second gimbal is provided for rotating the triad of gyroscopes and accelerometers at a predetermined control angular rate. The second gimbal axis is directed along an axis orthogonal to the plane described above whose orientation is fixed in inertial space (as, for example, the earth's polar axis if this plane is parallel to the equatorial plane of the earth). The direction of rotation about the second gimbal axis is periodically reversed.