Abstract: A position determining system for determining a position of a rotor of a rotating motor has sensors that are coupled to the rotor. The sensors generate, in response to a rotation of the rotor, a quadrature signal that has sine and cosine components. The position determining system calculates a sum (A2) of a squared value of the sine component (A2sin2x) and a squared value of the cosine component (A2cos2x). An amplitude correction factor (A) is calculated as the squared root of the sum (A2). An amplitude corrected sine component (sin(x)) is obtained by dividing the sine component (Asin(x)) by the amplitude correction factor (A). An amplitude corrected cosine component (cos(x)) is obtained by dividing the cosine component (Acos(x)) by the amplitude correction factor (A).

Abstract: The present invention relates to a rotary encoder for detecting an angle, and more particularly to an absolute encoder which can read a pattern even when rotating at high speed. The present invention also relates to an encoder reading device that projects a pattern formed on an encoder onto a light receiving means using light emitted from a light source means so as to read a position of the encoder. The light source means is configured to emit a pulse that is synchronized with a shift pulse for moving an electric charge to a transfer gate of the light receiving means, and that is sufficiently shorter than a time interval (accumulation time) of the shift pulse.

Abstract: A method, a selector switch and selector device, is provided for secure position detection of a selector switch, which can be operated in at least two positions, particularly in a vehicle. In the method, a code word composed of a data part and a test part is assigned to each selector switch position. The code word is generated in each selector switch position by a number of switches corresponding to the number of bits of the code word. The data part already indicates an unambiguous selector switch position. In each code word, the test part is determined corresponding to a defined imaging rule from the data part. The test part generated by the switches is compared with the test part formed on the basis of the imaging rule from the data part, and, from a comparison of the two test parts, a conclusion is drawn with respect to a correct or erroneous position detection of the selector switch.

Abstract: A magnetic encoder includes a magnetic drum having, on the outer peripheral surface thereof, magnetized portions spaced at equal pitches; a magnetic sensor unit opposed to the outer peripheral surface of the magnetic drum; magnetic sensors are provided in the magnetic sensor unit spaced at a distance smaller than one pitch of the magnetized portions; a calculation device for calculating two sets of vectorial signals, from detection-signal output levels of the magnetic sensors generated upon rotation of the magnetic drum or the magnetic sensor unit, using the following equations (1) and (2):

Abstract: An encoding system is described for a media handling system including an endless belt. The encoding system includes encoding indicia associated with the endless belt. A first encoder transducer is responsive to the encoding indicia to provide a first encoder signal. A second encoder transducer is responsive to the encoding indicia to provide a second encoder signal, the second encoder transducer spatially separated from the first encoder transducer. An encoder processor is responsive to the first encoder signal and the second encoder signal to determine position data regarding the endless belt. Interruption of indicia due to a belt seam is accommodated by transferring belt position calculation from one transducer to the other as the seam passes between the two transducers. The processor is adapted to compensate for variations in the encoder indicia pitch caused by belt temperature differentials.

Abstract: This invention describes encoding methodology for the encoder assembly 18 which senses position of a shift motor 14 in a shift system 10. The basic motivation is robust operation of the shift system 10 in the event of an open circuit (OC) fault in the encoder output signal bus 20 or any fault in the encoder power supply line 80. It is assumed here that the controller 40 is unable to detect the said faults in a manner that is direct and independent of the sensed position code. The most important aspect of the encoding scheme is that the likely motor positions (main-stop positions) should be assigned as many logically high bits as possible. Next, no main-stop position should look like either Neutral or any of the two adjacent positions when an OC fault takes place in the bus 20. Finally, no position in the complete range of the travel of motor 14 should possess code which is identical to the power loss code (all logical zero's).

Abstract: A digital encoder control method of a digital control apparatus having a driving unit, a frequency signal generating unit for generating a pulse signal of a frequency according to a driving velocity of a driven member which is driven by the driving unit, an edge detecting unit for detecting a rising-up edge and a falling-down edge of the pulse signal, and a period data detecting unit for counting period data between edges detected by the edge detecting unit, wherein each time the edges are detected by the edge detecting unit, the period data between the same edges as the detected edges is outputted as control velocity data of the driving unit.

Abstract: An absolute-value encoder device for detecting a plurality of rotation quantities is disclosed. An A/B phase forming portion 610 forms an A-phase pulse signal and a B-phase pulse signal, based on light passing through a slit rotating together with a rotary shaft. One period of each of those pulse signals corresponds to one revolution of a rotary shaft. The A- and B-phase pulse signals are displaced in phase by 90° from each other. When an A/B-phase state detecting portion 640 detects a state change of each of those pulse signals, a clock forming portion 66 changes a frequency of a clock pulse signal to another frequency.

Abstract: A method of decoding a quadrature encoded signal where position tracking is implemented which decouples the position calculations from the encoder edges. In one embodiment of the present invention, a uni-directional pulse accumulator is used to count encoder edges, and a periodic interrupt timer is used to update the position information, where interrupts are generated independent from encoder edges. At slow speeds, the mode switches to monitor each encoder edge to check for direction reversal without requiring position information. This decodes bi-directional quadrature position information using a uni-directional counter and a count compensation method for resolving changes in direction.

Abstract: The present invention discloses an optical sensing system which uses a plurality of detectors installed at various positions next to an optical panel to generate a position signal for indicating the position of the optical panel. The optical sensing system has an optical panel having a plurality of sensing areas each having a plurality of encoding holes arranged in a predetermined direction, a sensing device having a plurality of detectors for detecting movements of the optical panel corresponding to the sensing device, each of the detectors being corresponded to one of the sensing areas of the optical panel for detecting movements of the encoding holes along the predetermined direction and generating correspondent sensing signals, and a control circuit electrically connected to the sensing device for collecting the sensing signals generated by the detectors of the sensing device to form a position signal so as to indicate the optical panel's position.

Abstract: A quadrature encoding device with slope-triggered digitizing circuit is provided for use in a mechanical mouse. The quadrature encoding device is capable of producing two square-wave signals indicative of the current mouse movement for position control of the mouse cursor on the computer screen. The slope-triggered digitizing circuit includes a delay circuit and an analog comparator, which is capable of generating a first voltage output when the slope of the opto-electrical signal from the photo detector is positive, and a second voltage output when the slope is negative. It is characteristic feature of the quadrature encoding device that the output characteristic of the slope-triggered digitizing circuit would not be affected by any deviations in the output characteristic of the associated photo detectors, and also would not be affected by the ambient light.

Abstract: A technique for hiding of data, including watermarks, in human-perceptible images, that is, image host data, is disclosed. In one embodiment a method comprises three steps. In the first step, data to be embedded is inputted. In the case of a watermark, this data is a unique signature, and may be a pseudo-noise (PN) code. In the case of hidden data to be embedded in the host data, this data is the hidden data itself, or the hidden data as spread against the frequency spectrum by a pseudo-noise (PN) code. In the second step, the inputted data is embedded within the host data, in accordance with a perceptual mask of the host data. The perceptual mask determines the optimal locations within the host data to insert the inputted data. In the case of images, these optimal locations are determined by reference to the human visual system. In the third step, the host data, with the embedded data, is further masked by a non-frequency mask. In the case of image data, the non-frequency mask is a spatial mask.

Abstract: An absolute position detection apparatus which comprises sine and cosine wave generators for generating one or more sets of sine and cosine waves within a cycle, analog-to-digital converters for converting the incoming sine and cosine waves generated by the sine and cosine wave generators into digital values. An arithmetic unit is used for calculating a compensation for errors including offset, amplitude and phase errors on the basis of the digital values from the analog-to-digital converters. In the apparatus, the arithmetic unit operates on a phase angle from phase angles found by the arithmetic performed prior to or during said error compensations and the digital values from the analog-to-digital converters, whereby a low-priced, highly reliable absolute position detection apparatus can be achieved without the addition of compensation circuits to the hardware.

Abstract: A system for controlling a plurality of function-specific modules in a high-volume electronic printing apparatus involves assigning a unique connection code to each physical connection between a pair of modules in the system. In order for a central control system to identify specific modules when the system is operating, each module is assigned a unique identification code which is a concatenation of the connection codes for the connections to other modules. Each module in a large system is thus identified by a unique code determined by its neighboring modules.

Abstract: A magnetic-type absolute position encoder includes a magnetic drum having a magnetic material magnetized on a circumferential surface thereof is rotated and absolute position in one revolution is calculated based on sinusoidal and cosinusaoidal signals outputted by a magnetic reluctance element arranged to oppose the circumferential surface. The polarities of a magnetic material (2) magnetized on the circumferential surface of a magnetic drum (1) are aligned in the direction of the rotational axis of the magnetic drum to form a magnetization track (3). In a case where a sinusoidal signal having n cycles per revolution is to be generated, the magnetization track is made to undulate n cycles per revolution in the direction of the rotational axis. A sinusoidal signal and a cosinusoidal signal having a phase difference of 90.degree.

Abstract: An optical code reading device, including a unit having, for each of the tracks of the coded element, a pair of photodiodes, a differential amplifier receiving the outputs of the photodiodes and the trigger connected to the output of the amplifier, a shift register receiving the outputs from the unit, a control unit, a clock and apparatus for feeding to said unit signals adapted for simulating at will, for each channel, the bit level "0" or the bit level "1".

Abstract: An incremental optical code reader of the wholly integrated type including a reading assembly, a pair of photodiodes, a differential amplifier receiving the outputs of the photodiodes and a trigger connected to the output of the amplifier. An electronic assembly with "exclusive OR" logic gates, AND logic gates and OR logic gates, receiving the outputs of the triggers for the channels and feeding into the outputs.