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.

A method for controlling a planar drive system includes determining values of magnetic stator fields for different energizing currents and spatial regions in a two-dimensional array of magnetic field sensors, generating at least one magnetic stator field by applying energizing currents to stator conductors to electrically control a rotor, determining measured values of a total magnetic field via the magnetic field sensors for a plurality of the spatial regions to determine a position of the rotor, compensating contributions of the magnetic stator fields to the measured values of the total magnetic field determined by the magnetic field sensors, generating measured values of the magnetic field determined by the respective magnetic field sensors for the respective space regions, and determining a position of the rotor based on the generated measured values of the magnetic fields. The planar drive system includes at least a controller, a stator module, and a rotor.

The embodiments described herein are directed to systems and devices for electronically measuring the absolute position of one or more moving targets e.g., along the length of a metal beam using mutual capacitive sensing. The beam may be made of metal and may have a limited inset area to fit a position detection sensor device along its length. The moving targets may have no active elements and the position of multiple targets may be detected simultaneously along the beam. The systems and devices described herein do not utilize electronic position feedback and instead rely on an integrated ruler and minimize the total number of sensors required to support recalibration, thereby minimizing scan time (more sensors results in a linear increase in scan time).

The invention relates to a method for determining shifts in position in at least two different spatial directions between a first element and a second element which are movable relative to each other, with at least two sensors which measure contactlessly and are spaced, in the at least two different spatial directions, from at least two standards which are fixed to the second element, sensor areas of the at least two sensors opposing the at least two standards in the respective spatial direction and sensing said standards, wherein: —the at least two sensors scan the at least two standards and generate, in interaction with the at least two standards, output signals with which in combination an absolute position of the second element is determined, said absolute position being associated with a linear movement in a further spatial direction or with a rotary movement, and —wherein the output signals of the at least two sensors are also used to determine values which characterise the distance between the respective sensor and the corresponding standard of the second element in the associated spatial direction, are corrected as a function of the determined absolute position of the second element, and from which the shift in position of the second element relative to the first element in the respective spatial direction is determined.

An encoder is provided that is capable of suppressing accuracy deterioration even if a scale is disposed in a tilted manner with respect to a receiving unit by being rotated around an axis (i.e., a rotation axis) orthogonal to a receiving surface. The encoder 1 includes scale 2 and detection head 3. The detection head 3 includes light source (transmitting unit) 4 and light-receiving unit (receiving unit) 5. The light-receiving unit includes light-receiving surface (receiving surface) 50 and converts light received at the light-receiving surface 50 into differential detection signals with two phases and outputs the same. The light-receiving surface 50 includes element array group 7 including four element arrays 71-74 provided in a parallel manner along an orthogonal direction, with each element array 71-74 including a plurality of light-receiving elements (receiving elements) 500. The plurality of element arrays 71-74 in the element array group 7 are disposed at positions where the sum of: (i) a distance in the orthogonal direction from a reference position to a positive phase signal element array 71, 72; and (ii) a distance in the orthogonal direction from the reference position to the negative phase signal element array 73, 74, is the same for all the phases of the at least two phases.

An angle measuring device includes first and second component groups and a bearing. The first component group includes a scale element having a first graduation. The second component group has a first modular unit, including a position sensor, and a second modular unit, including first, second, and third position transducers, and a compensation coupling. The first and second modular units are connected in a torsionally stiff but axially and radially flexible manner. The angle measuring device is operable in first and second modes. In the first mode, the first graduation is scannable by the position sensor to determine a first angular position. In the second mode, the first graduation or a further graduation situated on the scale element is scannable by the position transducers to determine further angular positions. A corrected relative angular position is determinable based on the first angular position and the further angular positions.

An optical position-measuring device for determining a relative position of scales includes a light source, the scales and a detector. The scales are movable relative to each other along measurement directions and disposed in different planes in crossed relation to each other, and each have a graduation having grating regions which are arranged periodically and have different optical properties. At the first scale, the illumination beam is split into sub-beams, the sub-beams subsequently impinge on the second scale and are reflected back toward the first scale, and the reflected-back sub-beams strike the first scale again, where they are recombined, so that a resulting signal beam subsequently propagates toward the detector. The measuring graduation of one or more of the scales is configured as a two-dimensional cross grating which has a filtering effect that suppresses disturbing higher diffraction orders.

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.

Position information of a movable body within an XY plane is measured with high accuracy by an encoder system whose measurement values have favorable short-term stability, without being affected by air fluctuations, and also position information of the movable body in a Z-axis direction orthogonal to the XY plane is measured with high accuracy by a surface position measuring system, without being affected by air fluctuations. In this case, since both of the encoder system and the surface position measuring system directly measure the upper surface of the movable body, simple and direct position control of the movable body can be performed.

An encoder includes a disc and a sensor. The disc has a circular surface with a central axis and is rotatable around the central axis. The disc has a slit row provided on the circular surface. The slit row includes slits arranged in a circumferential direction of the circular surface around the central axis and in a radial direction of the circular surface. The sensor is provided opposite to the slit row on circular surface. The sensor has a first light receiver and a second light receiver. The first light receiver is configured to output a first light receiving signal as the slit row rotates along the circumferential direction when the disc rotates around the central axis. The second light receiver is configured to output a second light receiving signal as the slit row moves along the radial direction when the disc rotates around the central axis.