Abstract: A surface sensing device is mounted on an articulating probe head of a coordinate measuring machine. The device includes an elongate probe holder which is rotatable about an axis. An elongate sensing module includes a surface finish or surface roughness probe with a stylus tip. This is connected to the probe holder via an adjustable knuckle joint. To determine the geometry of the surface sensing device, including the tip normal and drag vector of the stylus tip, the orientations of the probe holder and the sensing module are determined by probing points which are spaced along their lengths, using a separate probe.

Abstract: A surface sensing device is mounted on an articulating probe head of a coordinate measuring machine. The device includes an elongate probe holder which is rotatable about an axis. An elongate sensing module includes a surface finish or surface roughness probe with a stylus tip. This is connected to the probe holder via an adjustable knuckle joint. To determine the geometry of the surface sensing device, including the tip normal and drag vector of the stylus tip, the orientations of the probe holder and the sensing module are determined by probing points which are spaced along their lengths, using a separate probe.

Abstract: A surface sensing device is mounted on an articulating probe head of a coordinate measuring machine. The device includes an elongate probe holder which is rotatable about an axis. An elongate sensing module includes a surface finish or surface roughness probe with a stylus tip. This is connected to the probe holder via an adjustable knuckle joint. To determine the geometry of the surface sensing device, including the tip normal and drag vector of the stylus tip, the orientations of the probe holder and the sensing module are determined by probing points which are spaced along their lengths, using a separate probe.

Abstract: A method of determining sub-divisional error of an encoder apparatus, which is configured to measure relative position of relatively moveable parts of an apparatus on which an inspection device for inspecting an artefact is mounted, includes causing the inspection device to inspect a feature so as to obtain measurements of a surface of the feature by relatively moving the relatively moveable parts of the apparatus. The method also includes using the measurements of the surface of the feature obtained by the inspection device during the inspection of the feature to determine the sub-divisional error of the encoder apparatus.

Abstract: A method of determining the sub-divisional error of an encoder apparatus that is configured to measure the position of relatively moveable parts of an apparatus on which an inspection device for inspecting an artefact is mounted. The method includes causing the inspection device to obtain measurements which includes relatively moving the relatively moveable parts of the apparatus, and using the measurements to determine the encoder apparatus' sub-divisional error.

Abstract: A method of locating a feature of an object in which the method includes bringing a stylus of a contact probe mounted on a positioning apparatus into contact with the object to obtain at least first and second measurements of the object. Each which the measurements gives rise to a range of possible points of contact between the object and a part of the stylus along its length and therefore inherently containing uncertainty in the location of the object along said length. The at least first and second measurements are used to reduce the extent of said uncertainty which includes using stylus orientation related information associated with the at least first and second measurements.

Abstract: A method of locating a feature of an object in which the method includes bringing a stylus of a contact probe mounted on a positioning apparatus into contact with the object to obtain at least first and second measurements of the object. Each which the measurements gives rise to a range of possible points of contact between the object and a part of the stylus along its length and therefore inherently containing uncertainty in the location of the object along said length. The at least first and second measurements are used to reduce the extent of said uncertainty which includes using stylus orientation related information associated with the at least first and second measurements.

Abstract: A method of operating a coordinate positioning apparatus having a surface sensor that is rotatable about at least a first axis. The method comprises obtaining a first measurement with the surface sensor at a first angular orientation and obtaining a at least a second measurement with the surface sensor at a second angular orientation. The first and second angular orientations are different to each other such that any offset of the surface sensor from an expected position will have at least a partially opposing affect on the first and second measurements. The method then compensates and/or establishes for the offset using the first and second measurements.

Abstract: A method and apparatus for controlling or programming a measurement path for a probe mounted on a coordinate positioning apparatus (e.g. an articulating probe head mounted on a CMM) which enables both the position of the probe tip and the orientation of the probe to be varied. In a first mode, the position of the probe tip is adjusted. In a second mode the orientation of the probe is adjusted, while keeping the location of the probe tip unchanged. This may be achieved either online on the coordinate positioning apparatus or offline in software.

Abstract: A method for orienting a surface sensing device (SSD) uses an apparatus having a support attachable to a moveable arm of a machine, such as a coordinate measuring apparatus. The support includes a first member rotatable about a first axis of rotation and a SSD for sensing the surface of a workpiece; the SSD is releasably connectable to the first member for rotation therewith. The method includes the steps of disconnecting a SSD from a support, the SSD being connected to the support in a first orientation; rotating one of the SSD and the support relative to the other of the SSD and the support and reconnecting the SSD and the support into a second orientation. An apparatus for orienting a surface sensing device is further described.

Abstract: An apparatus for measuring a surface of a workpiece is described. The apparatus comprises a support, attachable to the moveable arm of a machine, such as a coordinate positioning machine, and rotatable about first and second axes of rotation, the axes driven by first and second motors respectively. The apparatus additionally comprises a surface sensing device for sensing the surface of a workpiece, rotatable about a third axis of rotation. This third axis of rotation is alignable with the first axis of rotation, and when aligned, rotation of the support relative to the surface sensing device is actuatable by the first motor. A method for using an apparatus for measuring a surface of a workpiece is also described.

Abstract: A method and apparatus for controlling or programming a measurement path for a probe mounted on a coordinate positioning apparatus (e.g. an articulating probe head mounted on a CMM) which enables both the position of the probe tip and the orientation of the probe to be varied. In a first mode, the position of the probe tip is adjusted. In a second mode the orientation of the probe is adjusted, whilst keeping the location of the probe tip unchanged. This may be achieved either online on the coordinate positioning apparatus or offline in software.

Abstract: A method for orienting a surface sensing device (SSD) uses an apparatus having a support attachable to a moveable arm of a machine, such as a coordinate measuring apparatus. The support includes a first member rotatable about a first axis of rotation and a SSD for sensing the surface of a workpiece; the SSD is releasably connectable to the first member for rotation therewith. The method includes the steps of disconnecting a SSD from a support, the SSD being connected to the support in a first orientation; rotating one of the SSD and the support relative to the other of the SSD and the support and reconnecting the SSD and the support into a second orientation. An apparatus for orienting a surface sensing device is further described.

Abstract: A method for planning the trajectory of an apparatus, such as an articulating probe head, mounted on a coordinate positioning apparatus, such as a CMM. It is determined whether for a given trajectory, the angular velocity or acceleration of the apparatus about a rotational axis of the apparatus will exceed a predetermined threshold. If so, parameters are adjusted so that the angular velocity or acceleration do not exceed the threshold.

Abstract: A method of operating a coordinate positioning apparatus having a surface sensor that is rotatable about at least a first axis. The method comprises obtaining a first measurement with the surface sensor at a first angular orientation and obtaining a at least a second measurement with the surface sensor at a second angular orientation. The first and second angular orientations are different to each other such that any offset of the surface sensor from an expected position will have at least a partially opposing affect on the first and second measurements. The method then compensates and/or establishes for the offset using the first and second measurements.

Abstract: An apparatus for measuring a surface of a workpiece is described. The apparatus comprises a support, attachable to the moveable arm of a machine, such as a coordinate positioning machine, and rotatable about first and second axes of rotation, the axes driven by first and second motors respectively. The apparatus additionally comprises a surface sensing device for sensing the surface of a workpiece, rotatable about a third axis of rotation. This third axis of rotation is alignable with the first axis of rotation, and when aligned, rotation of the support relative to the surface sensing device is actuatable by the first motor. A method for using an apparatus for measuring a surface of a workpiece is also described.

Abstract: A method for planning the trajectory of an apparatus, such as an articulating probe head, mounted on a coordinate positioning apparatus, such as a CMM. It is determined whether for a given trajectory, the angular velocity or acceleration of the apparatus about a rotational axis of the apparatus will exceed a predetermined threshold. If so, parameters are adjusted so that the angular velocity or acceleration do not exceed the threshold.

Abstract: A method of calibrating an analogue probe (10) having a stylus (12) with a workpiece-contacting tip (14) or a non-contact probe (26). A calibration artefact such as a calibration sphere (16) is mounted on a coordinate measuring machine (CMM) (18). The probe (10,26) is mounted on an arm (8) of the CMM and the probe is moved along a path whilst continually scanning the surface of the calibration artefact such that the probe is exercised throughout its working range. For an analogue probe (10) having a workpiece-contacting stylus (12), the path is such that the deflection of the stylus varies along the path. For a non-contact probe (26) the path is such that there is variation of the radial distance between the path and the calibration artefact. The probe path may comprise a path parallel to a chord of the calibration sphere or a curved, e.g. a sinusoidal, path.

Abstract: A method of calibrating an analogue probe (10) having a stylus (12) with a workpiece-contacting tip (14) or a non-contact probe (26). A calibration artefact such as a calibration sphere (16) is mounted on a coordinate measuring machine (CMM) (18). The probe (10,26) is mounted on an arm (8) of the CMM and the probe is moved along a path whilst continually scanning the surface of the calibration artefact such that the probe is exercised throughout its working range. For an analogue probe (10) having a workpiece-contacting stylus (12), the path is such that the deflection of the stylus varies along the path For a non-contact probe (26) the path is such that there is variation of the radial distance between the path and the calibration artefact. The probe path may comprise a path parallel to a chord of the calibration sphere or a curved, e.g. a sinusoidal, path.