Rotary position sensor and method for determining a position of a rotating body

A rotary position sensor, comprising:

• a rotatable member comprising a first non-magnetic body portion and a plurality of magnets;
• a stator assembly comprising a second non-magnetic body portion with an aperture therein for receiving the rotatable member, the stator assembly further comprising a plurality of coils, the plurality of coils configured to generate waveform signals indicative of a position of the rotatable member in response to rotation of the rotatable member;
• and
• a housing comprising an interior region for enclosing at least a portion of the rotatable member and the stator assembly wherein the housing is constructed from aluminum and the housing comprises an alignment groove extending from an exterior surface of the housing inwardly into the housing, for positioning the housing.

A core extraction system for extracting a core from an earth formation, the core extraction system comprising:

• a drilling device used for extracting the core;
• and
• a system for controlling the drilling device, the drilling device comprising a rotating body, comprising:
• a position sensor comprising a rotatable member and a stator assembly, the rotatable member being operably coupled to the rotating body, the rotatable member comprising a first non-magnetic body portion and a plurality of magnets, the stator assembly comprising a second non-magnetic body portion configured to receive the rotatable member, the stator assembly further comprising a plurality of coils configured to generate waveform signals indicative of a position of the rotatable member in response to rotation of the rotatable member;
• and
• a controller operably communicating with the position sensor, the controller configured to control operation of the drilling device based on the signals of the position sensor.