A rotary, electromechanical device used to perform trigonometric computations by varying the magnetic couplings between its primary and secondary windings. It is generally used in circuits that solve vector problems, such as analog computers and conversion equipment. The resolver solves three different type problems: (1) Resolution - separating a vector into two mutually perpendicular components; (2) Composition - combining two components of a vector to produce a vector sum; and (3) Combination - the process of resolution and composition taking place simultaneously [15].