Accession Number : AD0679906

Title :   OPTIMUM ALIGNMENT OF INERTIAL NAVIGATION SYSTEMS,

Corporate Author : MASSACHUSETTS UNIV AMHERST SCHOOL OF ENGINEERING

Personal Author(s) : Hutchinson, C. E. ; De Sousa, E. A.

Report Date : NOV 1968

Pagination or Media Count : 88

Abstract : At present, the accuracy of an inertial navigation system is limited by the accuracy of the initial platform alignment process. The accuracy of the platform is further degraded by instrument errors; namely, gyro drifts, accelerometer errors, and independent velocity error sources. The specific alignment problem under consideration consists of placing the platform in a prescribed orientation as rapidly as possible under the constraints of maximum allowable error. The desire to align rapidly may be essential to successful mission accomplishments, so that limited restrictions are placed on the vehicle being navigated by inertial system. Consequently, it becomes necessary to design a control system to minimize the effect of these errors as rapidly as possible. This report compares two control schemes; namely, the Kalman estimator and the classical velocity feedback system, so that the best possible alignment be achieved. Presently the application of simple velocity feedback is the method employed in practice. However, with recent advances in modern control theory, the ability of the estimation scheme of Kalman to provide superior performance can be illustrated. The comparison is made with respect to two criteria: the ability of the control system to provide accurate alignment, and speed of response. A computer program has been developed to analyze and evaluate the relative merits of the optimum Kalman estimator and the classical feedback system. (Author)

Descriptors :   (*INERTIAL NAVIGATION, ALIGNMENT), INSTRUMENTATION, OPTIMIZATION, ACCURACY, ERRORS, CONTROL SYSTEMS, VELOCITY, FEEDBACK, CORRELATION TECHNIQUES, TIME, COMPUTER PROGRAMS, GYROSCOPES.

Subject Categories : Navigation and Guidance

Distribution Statement : APPROVED FOR PUBLIC RELEASE