Concatenated Approach to Trajectory Optimization

Abstract

the covariance simulationincorporatesthe equations developedpreviously.Inasmuchasthe Tomahawkmissileis being considered,the terrain scene is a terminal area digital scene matching and area correlation(DSMAC) scene. Shown in Fig. 2 is a typical CEP plot from the covariance simulation, which illustrates that the highly accurate positional solution obtained from the relative GPS correction vector scheme degrades only minimally between the DSMAC scene and the target. For target penetration considerations, the results presented here incorporate a terminal trajectory with a high-angle dive to impact the target. At the target, the navigational error contributes 2.6%, the steering error 10.2%, the scene center location error 20.9%, and the relative target location error 66.3%, which is consistent with the earlier discussion regarding relative error magnitudes. An examination of Fig. 2 also reveals that the correction vector scheme affords a substantial improvement over the situation where the Kalman e lter accepts a high-quality DSMAC positional update and, subsequently, the missile e ies in a free inertial manner to the target (the mode of operation for the current Block III Tomahawk missile ). Because improvements in satellite imaging technology are expected to permit larger DSMAC scene to target separations while maintaining the same scene/target relative error, free inertial navigation to the target will clearly become less desirable, and relative GPS schemes such as the one proposed herein more desirable. Summary