AAS 97-661
OPTIMAL CONES INTERSECTION TECHNIQUE FOR ATTITUDE POINTING ERROR EVALUATION
D. Mortari - Universita degli Studi "La Sapienaz" di Roma, Italy
Abstract
This paper optimizes the method for computing the spin axis based on the intersection of two cones forcing it to satisfy the Wahba optimality criterion. This is accomplished thanks to a demonstrated co-planarity condition among the observed and referenced directions. The paper then show that the method can be used to the optimal evaluation of any pointing direction and demonstrates that the described estimation technique is only a particular subset and an application of a general "Optimal Cones Intersection Technique", here developed and presented, which optimally estimates any on-board direction when n>2 observed directions are available. Some numerical tests validate the technique by means of meaningful plots.