A position sensor according to some embodiments includes a first position sensor board having first sensor coils and a first transmit coil; a second position sensor board having second sensor coils stacked with, and separated from by a distance Z, the first position sensor; and at least one target positioned relative to the stacked first position sensor and second position sensor. A redundant position sensor according to some embodiments includes a plurality of stacked sensor boards, each of the plurality of sensor boards including sensor coils, wherein one of the plurality of stacked sensor boards includes an active transmit coil; and a target positioned over the plurality of stacked sensor boards.

An inductive absolute position sensor has a scale with planar conducting features on a pattern repeating every spatial period T.sub.C along a measuring path and a reading head with planar windings: multipolar sine and cosine sense windings of spatial period T.sub.F=T.sub.C/M, M an integer, a unipolar first drive winding surrounding the sense windings and a multipolar second drive winding of spatial period T.sub.C/N along the measuring path, with N=M±1. An electronic circuit makes a first mode measurement using the first drive winding and a second mode measurement using the second drive winding. The absolute position in a range T.sub.C is computed from both modes' measurements. The sensor may be as compact as the incremental sensor it replaces, as the scale pattern and second drive winding needed for making it absolute do not need extra space.

The described techniques are directed to inductive torque sensors that implement independent target coil and pickup coil systems. By utilizing the various principles of inductive angle sensors, and as a result of the specific physical arrangement of target coils, the inductive torque sensor may independently obtain a rotational position (i.e., mechanical angle) of the rotatable input shaft via one pickup coil system, and a rotational position (i.e., mechanical angle) of the rotatable output shaft via another pickup coil system. Combiner circuitry is also provided to calculate the torsion angle using the signals induced in each of two separate pickup coil systems. By using different k-fold symmetry periodicities in the target coils with respect to the coil configurations, the inductive torque sensor advantageously reduces or eliminates mutual coupling between the different target coil systems and provide robustness to stray or external electromagnetic fields.

The present invention provides a signal processor that improves a resolution of a phase detection without increasing a clock frequency of a controller or decreasing a frequency of an excitation signal. A signal processor 10 includes a comparator 11 that compares a signal obtained by phase modulating a carrier frequency at a rotor rotation angle of a resolver with a dither signal.

An encoder scale, displaced relative to a detector head, includes: an insulating substrate; a conductive adhesive layer that is formed on the insulating substrate; and conductive pattern layers that are formed on the adhesive layer in a shape enabling the detector head to detect a position, wherein: the adhesive layer electrically connects all the pattern layers and includes an out-of-detection-range pattern that extends outward from a position detection range of the detector head; and the out-of-detection-range pattern is grounded via a conductive member.

A method that includes: providing a structure that is movable along a first axis; coupling a sensor assembly to the structure, the sensor assembly comprising first and second eddy current sensors and first and second targets that are mounted to the structure for movement along the first axis; sensing the first target with the first eddy current sensor and responsively generating a first sensor signal; sensing the second target with the second eddy current sensor and responsively generating a second sensor signal; and using the first and second sensor signals to determine a location of the structure along the first axis in a manner that is insensitive to coordinated movement of the first and second targets along a second axis that is perpendicular to the first axis and a third axis that is perpendicular to both the first and second axes.

A system and method for monitoring analog front-end (AFE) circuitry of an inductive position sensor. A redundant AFE channel is provided and alternatively utilized with a sine AFE channel or a cosine AFE channel of the AFE circuitry to obtain a voltage difference that may result in a detection angle error at the electronic control unit (ECU) of the inductive position sensor.

A position sensor is presented. Some embodiments of a position sensor according to some embodiments includes a position sensor that includes a transmission coil; receive coils, the receive coils including at least one polarity change; a target configured to transit across the receive coils; and a controller configured to drive the transmission coil, receive signals from the receive coils, and provide a position response indicative of the target position over the receive coils, wherein the position response exhibits a first linear region of a first slope and a second linear region of a second slope.

The present invention relates to an unwound rotor (1) for an inductive angular displacement sensor, which rotor is rotatably movable about a first axis (X1) and symmetrical with respect to the first axis (X1), the rotor (1) having: —a central portion (10), —two active portions (20) on either side of the central portion (10) relative to the first axis (X1), each active portion (20) comprising an outer surface (21) and two connecting walls (221, 222) connecting the outer surface (21) to the central portion (10), the rotor (1) being characterised in that in a plane (P) normal to the first axis (X1), each connecting wall (221, 222) forms an angle (a) greater than 45° with a second axis (X2). The invention also describes an inductive angular displacement sensor comprising such a rotor.

In some embodiments, a method of correcting for errors in a rotational position sensor having a sine signal and a cosine signal is presented. The method includes compiling data from the sine signal and the cosine signal over a period of rotation of a motor shaft; determining offset correction parameters from the data; correcting the data with the offset correction parameters; determining amplitude difference parameters from the data; correcting the data with the amplitude difference parameters; determining phase difference parameters from the data; correcting the data with the phase difference parameters; and using the offset correction parameters, the amplitude difference parameters, and the phase difference parameters to correct the sine signal and the cosine signal.