A vernier sensor including a coarse sensor and a fine sensor may require calibration to ensure accurate position measurements. Calibration may include determining coefficients for harmonics that can be added to the coarse sensor output and the fine sensor output to reduce harmonic distortion. The disclosure describes using the offset and variance of a difference signal as the basis for calibration. This approach is possible at least because the frequencies of the coarse sensor and fine sensor can be selected to reduce the complexity of these calculations.

A scale for inductive position measurement along a measurement direction X includes a support channel made of electrically conductive material having two interconnected spaced-apart side walls extending parallel to the measurement direction X and enclosing an interstitial space therebetween. A succession of first graduations made of electrically conductive material are disposed on the support channel, located in the interstitial space opposite and spaced from one of the two side walls and extending parallel to the measurement direction X. A succession of second graduations made of electrically conductive material are disposed on the support channel, located in the interstitial space opposite and spaced from the other one of the two side walls and extending parallel to the measurement direction X. The succession of first graduations and the succession of second graduations form a gap configured to receive a scanner operable to inductively scan the first graduations and the second graduations.

Aspects of this disclosure relate to a magnetic sensor system for measuring any desired combination of measuring torque, rotation angle, and turn count of a shaft. The shaft may include two portions connected by a torsion element. The system can measure rotation angle using a magnetic target coupled to the shaft that produces a magnetic field that varies as a function of rotation angle. The system can measure torque applied to the shaft by measuring the difference in rotation angles between the two portions of the shaft and factoring in a torsion coefficient. The system can track a turn count of the shaft using a multi-turn sensor. The magnetic sensor system may be part of an electric power assisted steering (EPAS) system.

The present invention provides an apparatus for sensing rotor location, the apparatus comprising: a sensing magnet; and a substrate arranged above the sensing magnet, wherein the sensing magnet comprises a main magnet and sub-magnet, the substrate comprises a first sensor and second sensor arranged along the same circular path with respect to the center of the sensing magnet, the first sensor comprises a plurality of first hole sensors adjacent to each other on the circular path, the second sensor comprises a plurality of second hole sensors adjacent to each other on the circular path, the plurality of first hole sensors are arranged separated by a first angle along the circumference of the circular path, the plurality of second hole sensors are arranged separated by the first angle along the circumference of the circular path, and the adjacent first hole sensor and second hole sensor are arranged separated by a second angle different from the first angle along the circumference of the circular path.

The present disclosure relates to a sensor assembly for simultaneously capturing an angular position and a torque of a rotatable shaft. The sensor assembly comprises, for determining the angular position, a main body, two additional bodies, which are arranged coupled for rotation on the main body, and two angle resolvers, which are arranged on a circuit board in the immediate vicinity of the additional bodies. In this arrangement, the angles of the additional bodies are determined by the angle resolvers and passed as an angle signal to an evaluation unit arranged on the circuit board. The sensor assembly further comprises a direct coating, which captures a torque signal from the rotating shaft and passes this signal over a connection line to the evaluation unit. The connection line has a section wound multiple times around the shaft to permit a rotation of the shaft by at least +/?900?.

A position sensor system is arranged for determining a position of a sensor device movable along a predefined path relative to a magnetic source. The system includes the magnetic source and the sensor device. The magnetic source has a first plurality of magnetic pole pairs arranged along a first track and a second plurality of magnetic pole pairs arranged along a second track, centrelines of the tracks are spaced apart by a predefined track distance. The sensor device is configured for measuring at least two orthogonal magnetic field components at a first sensor location, and at least two second orthogonal magnetic field components at a second sensor location. The first and second sensor location are spaced apart by a predefined sensor distance smaller than the predefined track distance, in a direction transverse to the tracks.

A multi-turn non-contact sensor includes a rotationally mounted driver magnet, and a rotationally mounted driven magnet. The driver magnet has a first number (P.sub.1) of magnetic poles and is configured to selectively receive a rotational drive torque and, upon receipt of the drive torque, to rotate about a first rotational axis. The driven magnet is spaced apart from, and is coupled to receive a magnetic force from, the driver magnet. The driven magnet has a second number (P.sub.2) of magnetic poles and is responsive to rotation of the driver magnet to rotate about a second rotational axis that is parallel to the first rotational axis. The driven magnet rotates one complete revolution each time the driver magnet rotates a predetermined number (N) of complete revolutions, P.sub.2>P.sub.1, and N=(P.sub.2/P.sub.1).

A rotary encoder for measuring absolute rotation around an axis of the rotary encoder, comprising: a magnetised element comprising first and second surfaces at an angle to one another; a first magnetic track provided on the first surface and a second magnetic track provided on the second surface, wherein the first and second magnetic tracks subtend an angle around the axis of the rotary encoder, wherein each magnetic track comprises a number of magnetic pole pairs, a magnetic pole pair being formed of two poles defining regions of opposite magnetic polarization, wherein the number of magnetic pole pairs in each track are different and have a greatest common factor of one; and first and second magnetic sensor arrangements, the first magnetic sensor arrangement arranged to detect a magnetic field of the first magnetic track and the second magnetic sensor arrangement arranged to detect a magnetic field of the second magnetic track, wherein the magnetic sensor arrangements are rotatably coupled to the magnetised element around the axis of the rotary encoder.

A steering angle detecting apparatus includes a steering angle sensor and a diagnostic unit. The steering angle sensor includes two relative steering angle detectors and an absolute steering angle processor. The two relative steering angle detectors detect a plurality of two relative steering angles. The absolute steering angle processor calculates absolute steering angles. The diagnostic unit determines whether an angular signal indicating an absolute steering angle of the absolute steering angles is outputted from the absolute steering angle processor. The diagnostic unit stores a latest absolute steering angle, determines which of the two relative steering angle detectors outputs one of the two relative steering angles, and, where one of the two relative steering angle detectors is determined as outputting the one of the two relative steering angles, update the latest absolute steering angle by adding outputted one of the two relative steering angles to the stored latest absolute steering angle.

The invention relates to a sensor arrangement (7) for detecting a position and/or a displacement of a flux element assembly (8) along a longitudinal direction, with a coil assembly (1) and the flux element assembly (8), wherein the coil assembly (1) comprises at least two flat coils (2a, b), wherein the flux element assembly (8) comprises at least two flux elements (9a, b), wherein the at least two flux elements (9a, b) are arranged adjacent to one another in the longitudinal direction and offset in transverse direction, wherein the flux element assembly (8) and the coil assembly (1) are movable and/or displaceable relative to one another in the longitudinal direction, wherein the flat coils (2a, b) are designed, such that an actual inductance (L.sub.1, L.sub.2) of each flat coil (2a, b) is dependent on the actual displacement of the flux element assembly (8) relative to the coil assembly (1), with an evaluation device, which is set up to determine the actual inductance (L.sub.1, L.sub.2) for each flat coil (2a, b) and determine the actual displacement based on the determined actual inductances (L.sub.1, L.sub.2).