Navigation computation in terrestrial strapdown inertial navigation systems
Abstract
Various computational schemes for computing the translational velocity and position relative to earth, a computation which has to be performed by the processor of a strapdown inertial navigation system, are compared. A splitcoordinate approach was selected in which the differential equations are solved at different computational rates. The differential equations of this scheme are developed and the assumptions on which the development is founded are stated. It is shown that the splitcoordinate approach can be used only if the gravitational acceleration is assumed to be piecewise constant and is updated at the slowest computational rate. Then the intermediaterate computation has to be carried out in an earthfixed coordinate system rather than in a locallevel, localnorth system.
 Publication:

IEEE Transactions on Aerospace Electronic Systems
 Pub Date:
 November 1977
 DOI:
 10.1109/TAES.1977.308509
 Bibcode:
 1977ITAES..13..679B
 Keywords:

 Differential Equations;
 Digital Navigation;
 Inertial Navigation;
 Signal Processing;
 Strapdown Inertial Guidance;
 Acceleration (Physics);
 Angular Velocity;
 Cartesian Coordinates;
 Computation;
 Gravitational Effects;
 Position Errors;
 Space Communications, Spacecraft Communications, Command and Tracking