An encoder includes a base portion, a scale portion that is provided to be relatively rotatable with respect to the base portion, and has a plurality of marks, an imaging element that is disposed in the base portion, and images the marks, and an estimation portion that performs template matching on a captured image in the imaging element by using a reference image, in which the plurality of marks include a first mark and a second mark, and the estimation portion counts the number of pixels of the imaging element corresponding to a rotation angle of the scale portion with respect to the base portion until a position of the second mark is detected from detection of a position of the first mark, and performs calibration on the basis of the counted number of pixels and the rotation angle.

Template matching with an image captured by the first imaging element is performed to obtain a first movement amount in a circumferential direction of the first mark, template matching with an image captured by the second imaging element is performed to obtain a second movement amount in a circumferential direction of the second mark, and a rotation angle is calculated and output by using the first movement amount and the second movement amount.

A code plate including a pattern thereon is provided. The pattern includes a first set of codes and a second set of codes. The first set of codes is associated with a first waveform. The second set of codes is associated with a second waveform.

The present disclosure may be embodied as an optical encoder system comprising a first optical sensor, a second optical sensor, a first up-down counter, a second up-down counter, and an I/O expander. The optical encoder system may further include a buffer. The present disclosure may also be embodied as an optical encoder system comprising an optical encoder, and a monostable multivibrator. The present disclosure may also be embodied as a method for encoding optical data comprising generating a first optical sensor signal and a second optical sensor signal, converting the first optical sensor signal and second optical sensor signal into four first counter signals, generating a borrow output signal and a carry output signal, converting the borrow output signal and the carry output signal into four second counter signals, and converting the first counter signals and second counter signals into a serial data signal and a serial clock signal.

The present invention relates to a system and method for modelling the physical characteristics of a building. Models of buildings, such as floor plans, are often produced when renovation work or other work is planned. Manual measurements maybe taken (e.g. using a tape measure or an optical distance meter), and these measurements are subsequently used by a draftsman to construct a model of the measured space. This is time consuming. The present invention provides a system and method which includes a measurement and modelling process which assigns a unique identifier to openings that are shared by adjoining rooms when plotting measurements. These room associations are then used to determine the layout of the rooms within a building model. There is significantly less time and cost involved in generating a computer model of the measured space, using the present system and method.

An encoder includes a measurement target and circuitry. The measurement target includes an absolute pattern and is rotatable. The circuitry is configured to generate, via a processing scheme, a signal representing an absolute position of the measurement target based on the absolute pattern. The circuitry is configured to detect, based on the absolute pattern, whether the measurement target rotates or not. The circuitry is configured to change the processing scheme based on whether the measurement target rotates or not.

A position detection method includes obtaining a first phase value of a first signal that repetitively changes by a first cycle number, a second phase value of a second signal that repetitively changes by a second cycle number larger than the first cycle number, and a third phase value of a third signal that repetitively changes by a third cycle number larger than the second cycle number, selecting one cycle corresponding to the first phase value from cycles of the second cycle number, selecting one cycle corresponding to the second phase value and the cycle selected from the cycles of the second cycle number, obtaining a fourth phase value of the third signal corresponding to the second phase value of the cycle selected from the cycles of the second cycle number, and obtaining a position of the scale by using the third phase value and the fourth phase value.

By configuring an encoder scale as an angled or inclined magnet or pair of oppositely arranged, adjacent magnets, a magnetic field sensor in a travel path of the scale can detect an absolute position of the scale for use in an industrial control system. Due to the angle or incline, when a first side of the scale is proximal to the sensor, the sensor can detect an angle of 180. As the scale moves to center with respect to the sensor, the sensor can detect an increasing angle to 0. Then, as a second side of the scale becomes proximal to the sensor, the sensor can detect an increasing angle to +180. The angle changes linearly with position. In one aspect, the pair of oppositely arranged magnets can be rotated with respect to the travel path to provide the angle. In another aspect, the pair of oppositely arranged magnets can be magnetized diagonally to provide the angle.

A pattern for calibration of a detector, including of a series of contrasting light and dark segments; the segments being arranged such that the absolute position of any point on the pattern is determinable from a window portion of the pattern including the point; the window portion having a predetermined minimum number of segments, the predetermined minimum number of segments being less than the total number of segments in the series.

A position detecting apparatus includes a signal detecting unit that detects a plurality of periodic signals, a correction unit configured to correct the plurality of periodic signals using a correction value to generate a plurality of correction signals, a first calculating unit configured to generate a plurality of displacement signals based on the plurality of correction signals and to calculate the position based on the plurality of displacement signals, a second calculating unit configured to calculate a reliability based on the plurality of displacement signals, and a correction value adjusting unit configured to adjust the correction value based on the reliability. The second calculating unit calculates a first reliability corresponding to a first correction value and a second reliability corresponding to a second correction value, and changes the first correction value to the second correction value when the second reliability is higher than the first reliability.