Abstract: A measurement system has a surface sensing device mounted on an articulating probe head, which in turn is mounted on a coordinate positioning apparatus. The surface sensing device is moved relative to a surface by driving at least one of the coordinate positioning apparatus and probe head in at least one axis to scan the surface. The surface sensing device measures its distance from the surface and the probe head is driven to rotate the surface sensing device about at least one axis in order to control the relative position of the surface sensing device from the surface to within a predetermined range in real time.

Abstract: A method of calibrating an articulating probe head comprising the steps of measuring an artefact of known dimensions with the workpiece sensing probe mounted on the articulating probe head, in which the articulating probe head is unlocked. An error functional map is generated corresponding to the difference between the measured and known dimensions of the artefact. Subsequent workpieces are measured with the articulating probe head unlocked and the corresponding correction applied. The true dimensions of the artefact may be determined by measuring it with a probe mounted on an articulating probe head in which the axes of the articulating probe head are locked. A mechanical lock is provided to lock the axes of the articulating probe head.

Abstract: A method is described for calculating an optimum stand-off distance for surface position measurements to be acquired by a coordinate positioning apparatus including a measurement probe. The coordinate positioning apparatus may include a machine tool and the measurement probe may include a touch trigger probe having a deflectable stylus. The method includes the step of calculating an optimum stand-off distance using at least one measured acceleration characteristic of the coordinate positioning apparatus. In this manner, measurement cycle times may be optimised.

Abstract: A detecting system for detecting flaws in a sample includes an illumination assembly and detecting assembly. The illumination assembly has an infra-red light source and illumination optics for directing a beam of light from the light source to a spot on or within a sample. The detection assembly has a detector for detecting light from an illuminated spot on or within a sample and detection optics for directing light from an illuminated spot on or within a sample to the detector. Such a system may be used for determining flaws in a sample such as a thermal barrier coating on a turbine blade, or a dental or other medical part. In particular the system may be used for determining flaws in a ceramic sample. A method for detecting flaws in a sample is further described.

Abstract: A coordinate positioning apparatus is described. The coordinate positioning apparatus comprises a mounting surface, a motion guide mountable on the mounting surface, a first member comprising a sensor for sensing scale markings, the first member being mountable on the motion guide, and an encoder scale member comprising a first set of scale markings which are, in use, sensable by the sensor. At least part of the encoder scale member is retained between the mounting surface and the motion guide such that the encoder scale member is supported by the mounting surface at least in the vicinity of the first set of scale markings. The motion guide may be a guide rail or a bearing, for example. En encoder scale member for use with such a coordinate positioning apparatus is also described.

Abstract: An encoder scale is a piston rod for use in a pneumatic or hydraulic cylinder. The method includes the steps of providing a mask defining a required groove pattern on an encoder scale member that is formed from a first material (e.g. steel) and etching material from the encoder scale member, through the mask, to form a plurality of grooves in the outer surface of the encoder scale member. A second material such as copper is then deposited on to the encoder scale member to substantially fill the grooves, the second material having a different magnetic permeability than the first material. A machining process (e.g. grinding) is then used to remove any excess second material and thereby provide an encoder scale member having a substantially smooth outer surface. A step of coating the outer surface of the encoder scale member with a metal, such as chronium, is then performed.

Abstract: A magnetic scale includes a scale member having a plurality of grooves. The scale member defines a passive magnetic scale track. The plurality of grooves include grooves of at least a first groove type and a second groove type, the magnetic properties of the scale member in the locality of grooves of the first groove type being different than the magnetic properties of the scale member in the locality of grooves of the second groove type. The scale member is arranged to carry or encode absolute position information in the form of at least one codeword comprising a sequence of data bits, wherein each of the data bits is provided by a groove of the scale member, the data bit taking a first value if the groove is of the first groove type and a second value if the groove is of the second groove type.

Abstract: A computer-implemented method for determining a course of motion between an artefact (10) and device (28) for interacting with the artefact (10) that arc moveable relative to each other in at least one linear (X, Y, Z) and one rotational (A1, A2) degree of freedom, the method comprising: receiving geometric data representing the artefact (10); receiving geometric data representing the device; and determining, from the geometric data, how the device (28) and artefact (10) can be oriented relative to each other along an interaction path so as to comply with one or more optimisation criteria.

Abstract: A frequency tuneable or chirped laser device is described that includes a laser cavity formed from a plurality of optical components. The optical components include a laser source for generating a beam of light, a spectral tuning element and one or more further optical components for directing the beam of light on to the spectral tuning element. At least one of the plurality of optical components is moveable in a first degree of freedom; such movement simultaneously altering the effective optical path length of the laser cavity and the tuning frequency of the spectral tuning element. The effective optical path length and the tuning frequency of the device are substantially insensitive to any movement of said at least one moveable optical component in degrees of freedom other than the first degree of freedom. This provides frequency tuning in which mode hopping is suppressed.

Abstract: The invention relates to the transmission of power and/or data from/to a stationary part of a machine tool 200 to/from an accessory 100 mounted in the spindle 210 of the machine tool 200. A first electrical link or interface 1a,1b,1c,1d provides electrical communication between the stationary part 200 and the spindle 210, and a second electrical link or interface 3 is provided electrically connected to the first electrical link at the accessory mounting area 230. The second link 3 is in the form of electrical contacts. The invention extends to an accessory shank 360 for mounting to the spindle 210 of the machine tool, and also to an accessory 100 e.g. in the form of a measurement probe, connected to the said shank 360.

Abstract: Rotary encoder apparatus is described that comprises an encoder scale or ring and an encoder scale reader. The encoder scale includes an incremental scale and one or more reference marks. The encoder scale reader comprises at least a first readhead and a second readhead that each produce a reference mark signal when passed over a reference mark of the encoder scale. The apparatus also comprises a reference position setter for determining, as the encoder scale reader is rotated relative to the encoder scale, at least one angularly repeatable reference position of the encoder scale relative to the encoder scale reader using a first reference mark signal produced by the first readhead and second reference mark signal subsequently produced by the second readhead.

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 measurement system has a surface sensing device mounted on an articulating probe head, which in turn is mounted on a coordinate positioning apparatus. The surface sensing device is moved relative to a surface by driving at least one of the coordinate positioning apparatus and probe head in at least one axis to scan the surface. The surface sensing device measures its distance from the surface and the probe head is driven to rotate the surface sensing device about at least one axis in order to control the relative position of the surface sensing device from the surface to within a predetermined range in real time.

Abstract: A spectroscopic analysis method in which spectral data of mixtures obtained from a plurality of points on a sample surface are resolved into component spectra and concentrations. A new alternating least squares multivariate curve resolution technique is presented which iteratively resolves the components. The technique starts from an initial estimate that the spectral values of a first component of the sample are all equal (an ‘empty model’), and resolves that component. Then successive further components are iteratively resolved, from initial ‘empty model’ estimates of those components and from previously resolved spectra. In the common case where the main component is present in nearly pure form in the data set, this empty modelling technique results in more accurate resolution of the components. This is due to the ability of the technique to resolve the pure spectra of minor components without modelling concentrations of the main component into them.

Abstract: A method of calibrating an articulating probe head comprising the steps of measuring an artefact of known dimensions with the workpiece sensing probe mounted on the articulating probe head, in which the articulating probe head is unlocked. An error functional map is generated corresponding to the difference between the measured and known dimensions of the artefact. Subsequent workpieces are measured with the articulating probe head unlocked and the corresponding correction applied. The true dimensions of the artefact may be determined by measuring it with a probe mounted on an articulating probe head in which the axes of the articulating probe head are locked. A mechanical lock is provided to lock the axes of the articulating probe head.

Abstract: An apparatus for mounting a coordinate positioning apparatus accessory, such as a tool setter, to the workpiece mounting surface of a coordinate positioning apparatus, the workpiece mounting surface having a slot formed in it. The apparatus includes an insert for inserting into the slot of the workpiece mounting surface, and a mount attachable to a coordinate positioning apparatus accessory. The insert includes structure to fix the insert within the slot; the insert is substantially contained within the slot when inserted therein. The mount includes at least one protruding member for engaging the insert when contained within the slot, thereby fixing the mount, and therefore any coordinate positioning apparatus accessory attached to the mount, to the workpiece mounting surface of the coordinate positioning apparatus.

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: This invention relates to a method for measuring a feature of an object that comprises obtaining a representation of at least the feature on the object by acquiring multiple data points via surface measurement of at least the feature. A model substantially replicating at least the feature of the object is fitted to the representation. The model comprises parameters defining at least two independently alterable portions that are linked at a common point. The fitting comprises changing the form of the model by altering at least one of the at least two independently alterable portions. The method also comprises obtaining information regarding at least the feature from the fitted model.

Abstract: A back-lit vision machine apparatus is described that includes an imaging sensor for imaging an object. A radiation source for generating radiation having a first property and a radiation converter for converting radiation having the first property into radiation having a second property are also provided. The radiation source is arranged to project radiation having the first property onto the radiation converter thereby producing radiation having the second property, whilst the radiation converter is arranged to illuminate an object to be imaged by the imaging sensor with radiation having the second property. An object to be imaged is locatable between the radiation converter and the imaging sensor and such an object is thus back-lit by radiation having the second property produced by the radiation converter. The radiation source is arranged to project radiation having the first property onto the object to be imaged and onto the radiation converter.

Abstract: A connector is described that comprises a male connector portion that is releasably connectable to a complimentary female connector portion. The male fluid connector portion comprises a plurality of hollow needles that are each in fluid communication with a lumen of the associated tubing. The female connector portion comprises plurality of chambers or apertures that comprise a septum seal through which a hollow needle can be passed. Tubing having a plurality of lumens is coupled to the female connector portion and each lumen is in fluid communication with one of said chambers. The male and/or female connector portions also include an alignment guide that allows the hollow needles of the male part to be uniquely aligned with the corresponding septum seals of the female part. The use of the connector for medical purposes is described.