A generalized Hough transform is used to acquire and track vehicular
targets for missile guidance. This is accomplished by recognizing that
most vehicles have silhouettes that may be described as a "rounded
rectangle". The position and shape of such rounded rectangles is
described in terms of 5 parameters (x.sub.c, y.sub.c, a, b, .theta.)
where x.sub.c, y.sub.c are the center coordinates, a,b are the major and
minor axis and .THETA. is the orientation. The computation of a five
dimensional Hough transform on an image including such a target will
produce the five parameters that provide the "best fit" rounded rectangle
to the target. These parameters are then passed to a missile tracker.
This capability can be used to improve track gate handoff from the
automatic target recognizer (ATR) to the missile tracker, changing aspect
ratios of maneuvering targets, limited lock-on after launch (LOAL),
aimpoint designation and fire control system to missile seeker handover.