A general purpose maneuver turns computer program

The theory, functional description, and operating instructions of a general purpose maneuver analysis program are described. The program computes the maneuver turns required to point a given spacecraft-fixed vector in the direction of a given inertially-fixed vector. Any two-turn maneuver sequence may be arbitrarily chosen. If it is not possible to accomplish the desired orientation with a two-turn sequence, a three-turn sequence can be specified. The coordinates of an arbitrarily selected inertially-fixed reference vector are computed before and after each turn that is performed. Two program options provide the reference vector coordinates throughout each turn at selected points and the reference vector positions before and after each turn of an arbitrarily prescribed set of maneuver turns.