Abstract: A tool or attachment jig for mounting an optical triangulation sensor on a turbine blade in a position to measure the gap between the distal tip of the turbine blade and the adjacent shroud. The tool includes a device for indicating the orientation of the sensor. This means that the tool can match a measurement from the optical triangulation sensor with a position on the circumference of the shroud. By taking a plurality of measurements as the turbine blade is rotated with respect to the annular casing, an angular profile for the gap between the turbine blade and the casing can be obtained in a much quicker and more efficient way than a conventional system.

Abstract: A tool or attachment jig for mounting an optical triangulation sensor on a turbine blade in a position to measure the gap between the distal tip of the turbine blade and the adjacent shroud. The tool includes a device for indicating the orientation of the sensor. This means that the tool can match a measurement from the optical triangulation sensor with a position on the circumference of the shroud. By taking a plurality of measurements as the turbine blade is rotated with respect to the annular casing, an angular profile for the gap between the turbine blade and the casing can be obtained in a much quicker and more efficient way than a conventional system.

Abstract: The invention provides a positioning device for locating a planar light beam emitted by an optical triangulation sensor across a diameter of a hole formed in a surface of an object. The positioning device has an adjustable guiding element which is capable of locating an optical triangulation sensor at the same distance away from holes have a range of diameters. The guiding element is movably mounted relative to a platform that is fixed to the optical triangulation sensor. The guiding element comprises a body which is insertable into the hole, the body having a pair of contact surfaces for contacting diametrically opposed portions of the hole, the pair of contact surfaces being opposed to each other in a direction orthogonal to the plane of the planar light beam.

Abstract: The invention provides a positioning device for locating a planar light beam emitted by an optical triangulation sensor across a diameter of a hole formed in a surface of an object. The positioning device has an adjustable guiding element which is capable of locating an optical triangulation sensor at the same distance away from holes have a range of diameters. The guiding element is movably mounted relative to a platform that is fixed to the optical triangulation sensor. The guiding element comprises a body which is insertable into the hole, the body having a pair of contact surfaces for contacting diametrically opposed portions of the hole, the pair of contact surfaces being opposed to each other in a direction orthogonal to the plane of the planar light beam.

Abstract: An optical, such as a laser, triangulation sensor is disclosed in which a configuration of an output light beam is controlled using a mask in front of a light source. The configuration may include a plurality of coplanar spatially separated planar light beams. The mask may be movable to provide different light beam configurations. Masking parts of the light beam enables unwanted features on the measurement surface to be omitted. Also disclosed is a guide element for an optical sensor for facilitating hole diameter measurement. The guide element has contact surfaces lying on a virtual conical surface which abut the hole edge to enable consistent placement of the light beam with respect to the hole centre. Also disclosed is a guide element for an optical sensor having an aperture for framing surface features, such as a rivert to permit accurate location of the light beam therewith.

Abstract: An optical e.g. laser triangulation sensor is disclosed in which a configuration of an output light beam is controlled using a mask (19) in front of a light source. The configuration may include a plurality of coplanar spatially separated planar light beams. The mask may be movable to provide different light beam configurations. Masking parts of the light beam enables unwanted features on the measurement surface to be omitted. Also disclosed is a guide element (200) for an optical sensor for facilitating hole diameter measurement. The guide element has contact surfaces (212, 214, 216) lying on a virtual conical surface which abut the hole edge to enable consistent placement of the light beam with respect to the hole centre. Also disclosed is a guide element (300) for an optical sensor having an aperture for framing surface features (e.g. rivet) to permit accurate location of the light beam therewith.