Measuring distance along a wire rope, by steps that include moving the wire rope across a sensor head; counting rotations of a rotary encoder driven by the moving wire rope; detecting a first distance marker crossing the sensor head at a first position of the wire rope; detecting a second distance marker crossing the sensor head at a second position of the wire rope; and establishing calibration parameters for producing a calibrated distance measurement corresponding to any output of the rotary encoder, based at least on correlating a known distance between the first and second distance markers to a counted number of pulses of the rotary encoder between the first and second positions of the wire rope.

A position sensor arrangement, comprising: a magnetic source and a position sensor device movably arranged relative to each other; the latter comprising at least three magnetic sensors for measuring said magnetic field; a processing unit for determining a position based on a ratio of a first pairwise difference and a second pairwise difference, the first pairwise difference being a difference of a first pair of two signals, the second pairwise difference signal being a difference of a second pair of two signals. A method of determining a position, by performing said measurements, and by calculating said differences and said ratio. A method of calibrating said position sensor, including the step of storing at least one parameter or a look-up table in a non-volatile memory. A method of auto-calibration.

A method for calibrating a rotary encoder for measuring a rotary angle position of a machine shaft. The method includes rotating a machine shaft; measuring a start measuring point with a sensor unit; activating a timer module to measure a time value; measuring an intermediate measuring point with the sensor unit; storing the actual rotary angle position of the intermediate measuring point and the time value associated therewith; measuring an end measuring point with the sensor unit; recording a time value incremented by the timer module which reflects a runtime for a rotary motion of the start to the end measuring point; calculating at least one time-dependent reference rotary angle position; calculating a deviation between the actual rotary angle position measured and the at least one time-dependent reference rotary angle position calculated for at least one time value; and correcting an output signal from the rotary encoder via the deviation.

The various embodiment of the present disclosure provides a system to define and identify an absolute mechanical reference position for a rotating element, The system comprises a radial ring magnet comprising plurality of pole pairs mounted to the rotating element, a first magnetic sensor in proximity of the radial ring magnet to detect angular position of said rotating element, at least one second magnetic sensor in proximity of the radial ring magnet to detect the passage of each of the pole pair and a control module adapted to define said absolute mechanical position by computing a unique first set of feature values for each of said plurality of pole pairs based on responses of said first magnetic sensor and said second magnetic sensor. The first set of feature values is stored in a memory unit.

A method is for calibrating a multiturn sensor for determining the position of a spindle of a clutch actuator, in which the multiturn sensor (5) is operatively connected to a magnetic field of a permanent magnet (12) in that the multiturn sensor (5) is combined with an actuator transmission (3) which comprises a spindle (9) bearing the permanent magnet (12). In a calibration method which can be carried out particularly quickly and cost-effectively, during the assembly of the multiturn sensor (5), arranged on a carrier element (4), with the actuator transmission (3) bearing the spindle (9), the multiturn sensor (5) is operated outside its specified rotational range (0, n), wherein a position, set by actuating the actuator transmission (3), of the spindle (9) bearing the permanent magnet (12) provided for an operating case of the clutch actuator (1), is assigned to a specified end position of the rotational range (0, n) of the multiturn sensor (5), as a result of which a magnetic field of the permanent magnet (12) is aligned with the multiturn sensor (5).

A method for determining runout error includes generating a first magnetic field to interact with a second magnetic field generated by four or more poles of a magnet ring mounted to a first platform. The interaction may cause the first platform to rotate relative to a second platform. The method may further include receiving, from a magnetic field sensor, data including respective boundaries between neighboring poles of the four or more poles relative to a corresponding nominal boundary defined by substantially uniform boundary spacing. The method may include determining a magnetic field pattern from the data and, based on the pattern, determining an angular position of the four or more poles. The method may further include determining an angular difference between the determined angular position and a nominal angular position. The method may also include determining a runout error based on an amplitude of the angular difference.

One example method involves generating a calibration control signal for controlling an actuator configured to rotate a first platform about an axis. The calibration control signal causes the actuator to rotate the first platform at least one complete rotation about the axis. The method also involves receiving encoder output signals. The encoder output signals are indicative of angular positions of the first platform about the axis about the axis. The method also involves receiving sensor output signals from an orientation sensor mounted on the first platform. The sensor output signals are indicative of a rate of change to an orientation of the orientation sensor. The method also involves determining calibration data based on given sensor output signals received from the orientation sensor during the at least one complete rotation. The calibration data is for mapping the encoder output signals to calibrated measurements of the angular positions of the first platform about the axis.

A method for automatic calibration of a camshaft sensor for a motor vehicle engine. The sensor includes a processing module configured to generate, from a raw signal indicative of the variations in a magnetic field which are caused by a rotation of a target and measured by a primary cell, an output signal indicative of the moments at which teeth of the target pass past the primary cell. The sensor further includes two secondary measurement cells. The calibration method therefore makes it possible to determine two different switching thresholds for each tooth from a differential signal indicative of a difference in magnetic field measurement by the secondary cells. Also disclosed are a camshaft sensor implementing such a method, and a motor vehicle including such a sensor.

A method for calibrating a position measurement system includes receiving measurement data from the position measurement system and determining that the measurement data includes periodic distortion data. The position measurement system includes a nonius track and a master track. The method also includes modifying the measurement data by decomposing the periodic distortion data into periodic components and removing the periodic components from the measurement data.

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.