A capacitance sensation unit of plane position measurement device for performing measurement with submicron definition is able to measure both two-dimensional position and rotational angle relative to a plane object. The main application of the capacitance sensation unit is exemplified with the position measurement of the mover of a flat motor. The capacitance sensation unit is able to measure the position and rotational angle of the mover relative to the surface of a stator in the form of a flat plate.

An optical detecting device includes a reflecting element, a main body, a light source and a plurality of photosensitive elements. The reflecting element has a reflecting surface. The main body has an installing, surface. The installing surface at least partially faces to the reflecting surface. The main body is configured to move along, a moving direction relative to the reflecting element. The moving direction is substantially parallel with the reflecting surface. The light source is disposed on the installing surface and is configured to emit a light ray towards the reflecting surface. The photosensitive elements are disposed on the installing surface. Sides of the photosensitive elements close to the light source surround the light source to form a light source region. The light source is at least partially located in the light source region.

Methods and systems for measuring an axial position of a rotating component of an engine are described herein. The method comprises obtaining a signal from a sensor coupled to the rotating component, the rotating component having a plurality of position markers distributed about a surface thereof, the position markers having an axially varying characteristic configured to cause a change in a varying parameter of the signal as a function of the axial position of the rotating component. Based on the signal, the method comprises determining a rotational speed of the rotating component from the signal, determining the varying parameter of the signal, and finding the axial position of the rotating component based on a known relationship between the axial position, the rotational speed, and the varying parameter of the signal.

A dynamic displacement error compensation system by which detection error information obtained based on calibration detection of first and second axes, is respectively made into first and second compensation tables for compensating displacement on the axes by using positional information of the axes as variables, the first compensation table is stored in a first driver of a first motor device for driving a first moving element to move linearly on the first axis, the second compensation table is stored in a second driver of a second motor device for driving a second moving element to move linearly on the second axis, the drivers simultaneously or successively obtain a first dynamic positional information of the first moving element on the first axis and a second dynamic positional information of the second moving element on the second axis, and the moving elements are respectively displaceably compensated according to the compensation tables.

Apparatus and method estimate a position of a movable stage. The apparatus comprises: a stator comprising 2D array of sensors arranged relative to one another to provide a plurality of stator-Y oriented sensor columns and a plurality of stator-X oriented sensor rows; a movable stage comprising a first Y-magnet array comprising a plurality of first magnetization segments generally linearly elongated in a stage-Y direction, each first magnetization segment having a stage-Y direction length, L.sub.yy, and a magnetization direction generally orthogonal to the stage-Y direction, the magnetization directions of the plurality of first magnetization segments exhibiting a first magnetic spatial period λ.sub.x over a stage-X direction width, W.sub.yx, of the first magnet array; and a controller connected to receive information based on an output from each of the sensors and configured to use the information to determine a stator-X direction position of the movable stage.

Disclosed is an alternating electric field based plane 2D time-grating displacement sensor which includes two parts: the base of fixed ruler and the base of moving ruler, and the two parts are installed in parallel. The base of fixed ruler is arranged with square excitation electrodes that are respectively staggered coded along axis X and Y, and the base of moving ruler is arranged with induction electrodes arranged adjacently along X-axis and Y-axis, and the four induction groups respectively output four traveling wave signals through electric field coupling, and summation of adjacent output signals with an adder can simultaneously decouple two traveling wave signals with opposite phases and only containing X-axis displacement and two traveling wave signals with opposite phases and only containing Y-axis displacement; two traveling wave signals in either direction are differenced by a subtractor to eliminate common mode interference.

Disclosed is an alternating electric field based plane 2D time-grating displacement sensor which includes two parts: the base of fixed ruler and the base of moving ruler, and the two parts are installed in parallel. The base of fixed ruler is arranged with square excitation electrodes that are respectively staggered coded along axis X and Y, and the base of moving ruler is arranged with induction electrodes arranged adjacently along X-axis and Y-axis, and the four induction groups respectively output four traveling wave signals through electric field coupling, and summation of adjacent output signals with an adder can simultaneously decouple two traveling wave signals with opposite phases and only containing X-axis displacement and two traveling wave signals with opposite phases and only containing Y-axis displacement; two traveling wave signals in either direction are differenced by a subtractor to eliminate common mode interference.

An angle measuring device includes first and second component groups and a bearing. The first component group includes a scale element having first and second graduations. The second component group has a first modular unit, having a position sensor, a second modular unit, having first to sixth position transducers, and a compensation coupling. To determine the relative angular position between the component groups, the first graduation is scannable with the aid of the position sensor. Using the first to third position transducers, the first graduation or a further graduation disposed on the scale element is scannable to determine a displacement of the scale element in a plane. Using the fourth to sixth position transducers, the second graduation is scannable to determine tilting of the scale element about a tilting axis, the position sensor being situated in a torsionally stiff but axially and radially flexible manner relative to the position transducers.

A sensor system and a joystick including the sensor system. The sensor system comprises a magnetic field sensor, and first and second magnetic sources. The first magnetic source is rotatable relative to a sensitive surface of the sensor and generates a first magnetic field contribution of at least quadrupolar order. The second magnetic source is pivotable with respect to the sensitive surface and generates a second magnetic field contribution. The sensor is configured for detecting at least an in-plane component of a superimposition field of the first and second magnetic contributions at a plurality of lateral measurement locations on the sensitive surface, obtaining measurements, and determining a rotation angle for the first source from the field gradient measurements and two angular directions for the second source from the field mean measurements. Lateral measurement locations are arranged into two pairs of diametrically opposite measurement locations with respect to the sensitive surface.

An inductive position measuring device includes a scanning element and a scale element. The position measuring device is able to determine positions of the scanning element relative to the scale element in a first direction and in a second direction. The scale element includes graduation structures arranged next to one another along the first direction, and the graduation structures have a periodic characteristic with a second period length along the second direction. The scanning element has a first receiver track, a second receiver track, a third receiver track, and an excitation lead. Each of the three receiver tracks has two receiver circuit traces. The receiver circuit traces have a periodic characteristic with a first period length along the first direction, and the receiver tracks are arranged at an offset from one another in the second direction.