A method of measuring geometric parameters of through holes in a thin substrate includes acquiring images of select sub-volumes of the substrate using an optical system having a field of depth greater than a thickness of the substrate. The acquired images are processed to determine the desired geometric parameters.

A method of measuring geometric parameters of through holes in a thin substrate includes acquiring images of select sub-volumes of the substrate using an optical system having a field of depth greater than a thickness of the substrate. The acquired images are processed to determine the desired geometric parameters.

The disclosure provides a technical solution for determining centers and the spatial course of the centers of a hollow shaft rotatably clamped as a workpiece in a machine tool, which is machined on its outer surface at least in sections. The disclosure provides a technical solution in this respect using methods other than ultrasound. This aim is solved by using a sensor operating according to the eddy current principle, whereby process-engineering and device-engineering features are described in more detail.

The disclosure provides a technical solution for determining centers and the spatial course of the centers of a hollow shaft rotatably clamped as a workpiece in a machine tool, which is machined on its outer surface at least in sections. The disclosure provides a technical solution in this respect using methods other than ultrasound. This aim is solved by using a sensor operating according to the eddy current principle, whereby process-engineering and device-engineering features are described in more detail.

A downhole borehole imaging tool and methods for determining a borehole size includes a magnetoresistive system and a hub moveably coupled to a fixed tool string. The hub includes a magnet. The magnetoresistive system includes magnetoresistive sensors disposed within the fixed tool string and segregated from the magnet. During operation, a routine scan of all sensors measures, for example, the output voltage V, angle θ of magnetic field, and temperature. Measurements from each sensor may then be characterized to account for temperature and input voltages variation of the sensors. The most accurate measurement can be used to derive the position of the hub 44 using the previous baseline parameters stored in the tool.

A downhole borehole imaging tool and methods for determining a borehole size includes a magnetoresistive system and a hub moveably coupled to a fixed tool string. The hub includes a magnet. The magnetoresistive system includes magnetoresistive sensors disposed within the fixed tool string and segregated from the magnet. During operation, a routine scan of all sensors measures, for example, the output voltage V, angle θ of magnetic field, and temperature. Measurements from each sensor may then be characterized to account for temperature and input voltages variation of the sensors. The most accurate measurement can be used to derive the position of the hub 44 using the previous baseline parameters stored in the tool.

A system and method for measuring an inside diameter of a pipe to determine if it exceeds a predetermined value using a plurality of fingers operatively connected to a spring. When in a fully extended position, the distance between opposite fingers is the predetermined value. The fingers are pivotable between a starting position, through the fully extended position, and to a failing position. In the starting position, an outer end of each finger engages an inside surface of the pipe to compress the spring. If the diameter exceeds the predetermined value as the system moves through the pipe, the pipe inside surface will no longer engage the fingers, which releases the spring causing the fingers to pivot to the failing position, where they remain until the system is removed from the pipe and manually reset.

A caliper tool for measuring a shape of a wellbore may include a sensor assembly and a movable measurement component including a hub and a measurement arm extending from the hub, and a magnetically-permeable target coupled to the hub and configured to rotate with the hub upon movement of the measurement arm. A sensor assembly includes primary coil and one or more secondary coils spaced apart from the primary coil, wherein output signals from the secondary coils facilitates measurement of the shape of the wellbore.

A caliper tool for measuring a shape of a wellbore may include a sensor assembly and a movable measurement component including a hub and a measurement arm extending from the hub, and a magnetically-permeable target coupled to the hub and configured to rotate with the hub upon movement of the measurement arm. A sensor assembly includes primary coil and one or more secondary coils spaced apart from the primary coil, wherein output signals from the secondary coils facilitates measurement of the shape of the wellbore.

A method and system for estimating parameters of pipes. The method may comprise disposing an electromagnetic (EM) logging tool into a pipe string, creating a log from a first set of one or more measurements, and creating a synthetic model of one or more nested pipes based at least in part on a well plan. The method may further comprise adding a modeled pipe to the synthetic model, estimating one or more parameters of the modeled pipe through model calibration to form a calibrated model, and performing an inversion with the calibrated model to estimate one or more pipe parameters of the pipe string. The system may comprise an electromagnetic logging tool that may comprise a transmitter, wherein the transmitter is a first coil and is operable to transmit an electromagnetic field, and a receiver, wherein the receiver is a second coil and is operable to measure the electromagnetic field.