Abstract: In a system for controlling or monitoring an object, wherein a position of the object must be determined, the system includes a first and second multispeed sensor, the first sensor having a speed of N and the second sensor having a speed of N-1. A method for determining the position of the object comprises the steps of obtaining position data as measured by the first and second multispeed sensor, respectively. A parameter, N.sub.A, a weighted difference between the obtained position data, is determined to ascertain whether a first or second case exists. If the first case exists, a first set of constants based on a first set of equations is generated; otherwise the first set of constants is generated based on a second set of equations. A second set of constants is then generated. Finally, the position of the object is determined by calculating the weighted average of the second constants, thereby obtaining the position of the object, utilizing the data provided by both sensors.

Abstract: An apparatus for generating phase modulated angular positional signals in digital form. A phase tracking loop receives a phase modulated signal from the rotor of a resolver whose stator windings are excited in quadrature. The phase output of the resolver is proportional to the angular displacement of the rotor. Signals for exciting the stator windings of the resolver are applied in phase quadrature to a phase detector to develop an analog error signal when combined with the rotor output signal. The analog phase error signal provides an output indicative of the angular displacement of the rotor. The error signal is applied to a voltage controlled oscillator, converted to digital form, and combined with the excitation signals in a closed loop to force the error signal to a null, whereupon the indicated digital output angle is in coincidence with the angular displacement of the rotor shaft.