An example method includes: receiving a sine feedback signal and a cosine feedback signal from a resolver; generating a rectified sine signal and a rectified cosine signal; determining a direction of rotation of a shaft of an electric motor using the sine feedback signal, the cosine feedback signal, the rectified sine signal, and the rectified cosine signal; converting the rectified sine signal and the rectified cosine signal into a signed sine signal and a signed cosine signal, respectively, using information associated with determining the direction of rotation; determining a speed of rotation of the shaft using the signed sine signal and the signed cosine signal; comparing the direction and the speed of rotation to respective direction and respective speed of rotation determined by a resolver-to-digital converter; and operating the electric motor based on the comparing.

Methods and systems for encoding position markings are provided. A plurality of markings are identified, and are encoded by a processor. Each of the plurality of markings corresponds to one of a sequence of positions. The plurality of markings are encoded via the processor using a first digit representing a current position of the sequence of positions, and a plurality of additional digits, each of the plurality of additional digits representing a previous one of the positions of the sequence, such that the current position can be determined based on the first digit in combination with the additional digits.

An absolute encoder includes: a scale on which plural marks are arrayed; plural detecting devices each configured to detect a mark group of the plural marks and output a signal corresponding to the mark group; and a processor configured to obtain a coordinate of the scale based on outputs of the detecting devices. The plural marks are arrayed such that a signal obtained by adding plural signals respectively output from the detecting devices includes a periodic signal corresponding to plural periods. The processor obtains first position data based on a magnitude of at least one signal of the plural signals, obtains second position data having a resolution higher than that of the first position data based on a phase of the periodic signal, and generates data representing the coordinate based on the first and second position data.

An encoding sequence is configured to detect the position and direction of motion of an actuator. The actuator includes at least two members where one of the members moves with respect to the other. Two sets of binary indicators are either affixed to or integrally assembled along one of the members. Each pair of indicators defines a position of the actuator and each binary indicator is configured to identify one of two states, such as a magnetic pole or a graphical mark where each state corresponds to a logical zero or a logical one. The indicators are arranged on the actuator such that at least one of the indicators transitions between one of the two states at each position along the actuator. At least one sensor is provided to detect the state of the binary indicators as the two members of the actuator move with respect to each other.

A high-precision multi-pole magnetoelectric encoder includes a mounting seat, a rotating shaft, a single-pole magnet ring, a single-pole signal processing board, a shielding shell, an n-pole magnet ring, an n-pole signal processing board, a housing, a conductive rubber pad, an aviation plug, bearings, copper columns, Hall components, and assembly screws. The magnetoelectric encoder improves the environmental adaptability and replaceability of the high-precision multi-pole magnetoelectric encoder by redesigning the structure of the multi-pole encoder. It eliminates errors caused by changes in the position of magnets and Hall sensors during the replacement process, reduces interference caused by the multi-pole magnet encircling the single-pole magnet, enhances resistance to electromagnetic interference, thereby increasing the detection accuracy of the magnetoelectric encoder, and improves the performance and competitiveness of the product.

An encoding sequence is configured to detect the position and direction of motion of an actuator. The actuator includes at least two members where one of the members moves with respect to the other. Two sets of binary indicators are either affixed to or integrally assembled along one of the members. Each pair of indicators defines a position of the actuator and each binary indicator is configured to identify one of two states, such as a magnetic pole or a graphical mark where each state corresponds to a logical zero or a logical one. The indicators are arranged on the actuator such that at least one of the indicators transitions between one of the two states at each position along the actuator. At least one sensor is provided to detect the state of the binary indicators as the two members of the actuator move with respect to each other.

In a length or position measuring system which has an at least locally substantially linear measuring gauge and at least one sensor to be moved relative to the measuring gauge, wherein the measuring gauge includes an incremental track and at least one absolute track and wherein the incremental track and the at least one absolute track have poles arranged in the longitudinal direction of the measuring gauge, the poles of the at least one absolute track form at least two regions in the sensor with different field strengths or signal amplitudes.

In a length or position measuring system which has an at least locally substantially linear measuring gauge and at least one sensor able to be moved relative to the measuring gauge wherein the measuring gauge includes an incremental track and at least one absolute track and wherein the incremental track and the at least one absolute track have pole pairs arranged in the longitudinal direction of the measuring gauge, it is provided in particular that at least one pole pair of the absolute track is phase-shifted relative to a corresponding pole pair of the incremental track.

An absolute position detection device includes: a scale unit having a first member and disposed on a mover or a stator; a sensor unit having detection elements disposed at a first interval to detect position correspondence information corresponding to the first member; and a computation unit that: detects a distortion boundary position of output based on a comparison result between the position correspondence information by first and second detection elements; based on element coordinates of either the first or second detection element, element coordinates of a third detection element, the first interval, a length of the output pairs, and the position correspondence information by the third detection element, calculates a position of the third detection element to an end position of the first member; and calculates a positional relationship between the mover and the stator based on the calculated position and a length of the first member.

Provided are an absolute position measurement method, an absolute position measurement apparatus, and a scale. The scale includes a scale pattern formed by replacing repeatedly arranged pseudo-random-codes with a sequence of a linear feedback shift register of N stages using a first symbol with first width representing a first state and a second symbol with second width representing a second state. The first is divided into two or more first symbol areas of different structures, and the second symbol is divided into two or more second symbol areas of different structures. There is at least one overlap area in which the first symbol and the second symbol overlap each other to have the same structure.