Abstract: Absolute multi-turn position sensing integrated within the structure of a hybrid stepper motor implemented by sharing the magnetic structure of the motor with the sensing means. An alternating magnetic field is obtained from a single magnet within the stepper motor rotor by use of alternating flux paths directed to large Barkhausen jump effect sensing elements. Pulses generated from the large Barkhausen sensing are decoded electronically and stored in a non-volatile memory to absolutely locate the motor position within a fraction of 1 electrical cycle of the motor over an arbitrary range. This coarse position sensing can optionally be extended by use of a higher resolution absolute within-electrical-cycle sensing means to provide integrated high resolution position sensing over an arbitrary number of revolutions.

Abstract: An integrated motor and position sensor achieves motion between a moving portion and a stationary portion by electrically energizing poles to interact with magnetics respectively on the moving and stationary portions. The position sensor includes a plurality of sensing coils placed to intercept the magnetic flux between a plurality of the poles and the magnetics. The outputs from these coils are fed to a microprocessor DSP through an internal or external A/D converter. The microprocessor or DSP decodes the measured voltages using resolver strategies to produce a position, velocity or acceleration measurement.

Abstract: An AC synchronous motor, also known as a stepper motor, uses its magnetics and drive coils to produce both motion and excitation for sets of position sensing coils. Each drive phase is equipped with one or more sensing coils, which may be differentially wound, with the coils configured to act as secondaries of a linear variable differential transformer (LVDT). The primary of the so-formed LVDT is the motor drive winding. The outputs from these coils are fed to a microprocessor or DSP through an internal or external A/D converter. The microprocessor or DSP decodes the measured voltages using resolver strategies to produce a position measurement. An alternate mode of operation uses these same coils to form a variable reluctance resolver. This alternative mode of operation could be used for sensing coarse position while the motor drive is not energized.

Abstract: An integrated motor and position sensor achieves motion between a moving portion and a stationary portion by electrically energizing poles to interact with magnetics respectively on the moving and stationary portions. The position sensor includes a plurality of sensing coils placed to intercept the magnetic flux between a plurality of the poles and the magnetics. The outputs from these coils are fed to a microprocessor or DSP through an internal or external A/D converter. The microprocessor or DSP decodes the measured voltages using resolver strategies to produce a position, velocity or acceleration measurement.

Abstract: An AC synchronous motor, also known as a stepper motor, uses its magnetics and drive coils to produce both motion and excitation for sets of position sensing coils. Each drive phase is equipped with one or more sensing coils, which may be differentially wound, with the coils configured to act as secondaries of a linear variable differential transformer (LVDT). The primary of the so-formed LVDT is the motor drive winding. The outputs from these coils are fed to a microprocessor or DSP through an internal or external A/D converter. The microprocessor or DSP decodes the measured voltages using resolver strategies to produce a position measurement. An alternate mode of operation uses these same coils to form a variable reluctance resolver. This alternative mode of operation could be used for sensing coarse position while the motor drive is not energized.