Encoder system and method for determining absolute rotor position by taking a mid value of the multiple coil output sinusoidal signals

A method for determining absolute angular position of a rotor, the method comprising:

• generating at an inductance sensor a plurality of variable inductance values corresponding to the position of the rotor, the inductance values including mid values having near linear regions with determinable slopes and offsets;
• generating digital values of said inductance values corresponding to the angular position of the rotor;
• storing in a microcomputer having memory calibration data corresponding to said variable inductance values;
• and
• generating at said microcomputer an output signal responsive to said mid values and said calibration data, said output signal having a value corresponding to the angular position of the rotor.

A method for determining absolute angular position of a rotor, the method comprising:

• connecting an inductance sensor to the rotor, said inductance sensor generating phase separate pseudo-sinusoidal waveforms having near linear regions for mid values between a maximum value and a minimum value;
• exciting said inductance sensor to generate said phase-separated pseudo-sinusoidal waveforms, at least one of said waveforms having said mid values;
• storing calibration data for said inductance sensor in a memory of a computer, said calibration data including the slopes of said near linear regions and offsets for each of said waveforms;
• and
• generating with said computer a signal having a value indicative of the angular position of the rotor, in response to said at least one mid value and said calibration data.