Abstract:
A sensor, sensor disk, sensor measurement correction system, and method used in measuring a parameter in the refining zone. The sensor includes a spacer that spaces its sensing element from the disk. In one preferred embodiment, the spacer is made of an insulating material that insulates the sensing element from the thermal mass of the disk to prevent the thermal mass from affecting sensor measurement. The sensor includes a housing carried by the spacer that, in turn, carries the sensing element. Where the sensing element is a temperature sensing element, the housing is thermally conductive and the housing and spacer enclose the sensing element. Each sensor is disposed in the refining surface, preferably in its own separate bore in the disk and flush with or below axial refiner bar height. Signals from one or more sensors are processed by a processing device linked to a module containing calibration data that is applied to make sensor measurements more accurate. The module holds calibration data from sensors that are precalibrated before the sensor disk in which they are assembled is shipped, along with the module, to a fiber processing plant where the disk is installed in a refiner and the module connected to the processing device. In one preferred embodiment the sensor or sensors are carried by a sensor module that can be a removable segment of a refiner disk.
Abstract:
The present invention relates to a device for checking and calibrating high precision inclinometric sensors. It comprises a substantially quadrangular planar base body made of highly rigid material, set to float on mercury placed inside a tank; a pair of micrometric positioning means of known weights, situated in proximity to concurrent edges of the base body, on the respective axes of symmetry of the base body, able to allow to change the baricentre and the inclination on the mercury of the base body by a value determined by the variation in the applied moment; a pair of screws for adjusting the zero point, situated on said base body and a seat located centrally to the base body for positioning an inclinometric sensor to be calibrated.
Abstract:
For calibrating a spectrophotometer having a monochromator with a rotary mechanism to rotate a diffraction grating for producing a monochromatic beam of light of a specified target wavelength, transmission errors by the rotary mechanism are preliminarily measured to obtain an error curve having peaks corresponding to feed angles. A smallest angular interval, greater than an allowable limit, between a pair of feed angles corresponding to a mutually adjacent pair of peaks in the error curve is selected. One or more lamps emitting bright lines with wavelength interval which corresponds to motion of the rotary mechanism by less than one half of the selected smallest angular interval are used as a light source. Control values to be supplied to the rotary mechanism for obtaining monochromatic beams of light from the bright lines emitted from the selected lamps are determined by measurements. A calibration table, from which a required control value corresponding to a specified wavelength value can be retrieved, is produced from these control values and wavelength values of the bright lines and is stored in a memory device.
Abstract:
A method of detecting errors in air data sensing systems having multi-function probes being used in combinations to define probe systems includes a step (A) of, for each probe system, making a first prediction of an aircraft parameter as a function of local angles of attack at two member probes of the particular system, and making a second prediction of the aircraft parameter as a function of local pressure ratios at the two member probes of the particular system. A step (B) is performed in which, for each of the probe systems, the first and second predictions of the aircraft parameter are compared to determine whether the first and second predictions are within a predetermined threshold of each other. Then, a step (C) is performed in which, for each of the probe systems, if the first and second predictions of the aircraft parameter are not within the predetermined threshold of each other, then the particular probe system is identified as having a malfunctioning member probe.
Abstract:
The invention is a method and apparatus for improving the accuracy of an inertial navigation system. The method comprises (1) obtaining a measure of the angular velocity of a body frame of reference having a first axis, a second axis, and a third axis, (2) obtaining a measure of the acceleration of a first reference point in the direction of the first axis, a second reference point in the direction of the second axis, and a third reference point in the direction of the third axis, the first, second, and third reference points being fixed in the body frame, and (3) determining compensated acceleration values. A compensated acceleration value is the difference of the measure of acceleration of a reference point and a compensation quantity. A compensation quantity is an estimate of the portion of the acceleration of the reference point resulting from the rotation of the body frame. The method further comprises establishing the optimum navigation center based on a criterion of goodness. The criterion of goodness is minimal weighted acceleration error where acceleration error is a function of the direction of the angular velocity vector and weighted acceleration error is obtained by multiplying the acceleration error by a weighting function and integrating the result over all directions of the angular velocity vector.
Abstract:
An apparatus for measuring three-dimensional volumetric errors in a multiaxis machine tool is disclosed. The apparatus comprises a kinematic ball bar provided with two balls at both ends thereof as a basic construction. A U-shaped bar with two extension arms is integrated with the ball bar. A vertical post is positioned relative to the U-shaped bar and is integrated with one of the two balls. A sleeve is fitted over the post and two guide bars is fixedly and longitudinally assembled with an external surface of the sleeve at opposite positions. Each of the guide bars is provided with a slot at a lower portion thereof for movably receiving an operating pin.
Abstract:
A sensor array is bonded to or molded together with a micro-lens array to form a sensor cartridge. The micro-lenses of the micro-lens array are configured to focus light incident on the sensors, into the sensors. An alignment structure has a mating profile that receives and engages one or more micro-lenses from the micro-lens array to laterally align the cartridge to enable repeatable precise positioning of the cartridge.
Abstract:
An imaging sensor includes a defect marker allowing an imaging device in which the imaging sensor is installed to determine which pixels in the CMOS sensor are defective. During manufacturing, the pixels in the imaging sensor are tested. Defect markers are used for defective pixels, preferably using a non-volatile marking technique. After the imaging sensor is installed in the imaging device, the imaging device reads the defect markers from the imaging sensor to determine the defective pixels. The defect markers are read by exposing the pixels in the imaging sensor to photons. Eventually, all pixels in the imaging sensor should show some exposure. Pixels that still read as unexposed are then defective pixels. The imaging device can then compensate for defective pixels: e.g., by interpolating the defective pixels from their neighbors.
Abstract:
A method and apparatus for the calibration of vehicle wheel alignment sensors or optical targets and for the detection and correction of wear or damage to no-compensation type wheel adapters to which the vehicle wheel alignment sensors are attached during a vehicle wheel alignment procedure. A first aspect of the present invention is a method for electronically storing separate calibration values associated with a vehicle wheel alignment sensor or optical target for a variety of types of vehicle wheel adapters. A second aspect of the present invention is a method and apparatus for detecting and compensating for wear or damage to no-compensation type wheel adapters by utilizing a known flat surface against which the contact points of the adapter are placed, any misalignment of the sensor mounting shaft axis from the plane is detected and corrected for, either by adjustment of the contact points or by adjustment of the sensor mounting shaft. An additional aspect of the present invention is the inclusion of more than three contact points on the wheel adapter to which the vehicle wheel alignment sensor is attached to facilitate detection of damage or wear to the wheel adapter by providing a visual indication of the damage or wear when the wheel adapter is placed on the flat surface.
Abstract:
A sensor, sensor disk, sensor measurement correction system, and method used in measuring a parameter in the refining zone. The sensor includes a spacer that spaces its sensing element from the disk. In one preferred embodiment, the spacer is made of an insulating material that insulates the sensing element from the thermal mass of the disk to prevent the thermal mass from affecting sensor measurement. The sensor includes a housing carried by the spacer that, in turn, carries the sensing element. Where the sensing element is a temperature sensing element, the housing is thermally conductive and the housing and spacer enclose the sensing element. Each sensor is disposed in the refining surface, preferably in its own separate bore in the disk and flush with or below axial refiner bar height. Signals from one or more sensors are processed by a processing device linked to a module containing calibration data that is applied to make sensor measurements more accurate. The module holds calibration data from sensors that are precalibrated before the sensor disk in which they are assembled is shipped, along with the module, to a fiber processing plant where the disk is installed in a refiner and the module connected to the processing device. In one preferred embodiment the sensor or sensors are carried by a sensor module that can be a removable segment of a refiner disk.