Abstract: A method builds a workpiece using an additive manufacturing process, wherein the workpiece is built up by consolidating material in a layer-by-layer manner. The method includes receiving an initial geometric model defining surface geometry of the workpiece, determining workpiece slices to be consolidated as layers of the workpiece during the additive manufacturing process from the initial geometric model, determining adjusted positions of the workpiece slices adjusted from initial positions of the workpiece slices as determined from the initial geometric model, the determination of the adjusted positions based upon warping of the workpiece expected to occur during or after the additive manufacturing process, and building the workpiece using the additive manufacturing process, wherein the workpiece slices are formed in the adjusted positions.

Abstract: A method of monitoring an additive manufacturing apparatus. The method includes receiving one or more sensor signals from the additive manufacturing apparatus during a build of a workpiece, comparing the one or more sensor signals to a corresponding acceptable process variation of a plurality of acceptable process variations and generating a log based upon the comparisons. Each acceptable process variation of the plurality of acceptable process variations is associated with at least one state of progression of the build of the workpiece and the corresponding acceptable process variation is the acceptable process variation associated with the state of progression of the build when the one or more sensor signals are generated.

Abstract: A powder bed fusion apparatus in which selected areas of a powder bed are solidified in a layer-by-layer manner to form a workpiece, the powder bed fusion apparatus including a build chamber for maintaining an inert atmosphere or (partial) vacuum, a build sleeve located within the build chamber, a build platform for supporting the powder bed movable in the build sleeve, a powder applicator for forming powder layers of the powder bed and a radiation device for generating and steering a radiation beam across a surface of the powder bed to solidify areas of each layer, wherein the build sleeve is mounted in the build chamber to be tiltable to cause displacement of powder from the build sleeve through an opening in the build sleeve.

Abstract: This invention concerns apparatus for generating instructions for machines of a manufacturing chain used to manufacture a workpiece. The apparatus comprising a processor arranged to receive a model based definition (MBD) of a workpiece including geometric dimensions and tolerances; receive inputs setting an additive build design for building the workpiece based upon the geometric dimensions; generate additive instructions for an additive manufacturing machine of the manufacturing chain based upon the additive build design; determine a prospective intermediate workpiece product expected from an additive build in accordance with the additive build design; determine differences between the prospective intermediate workpiece product and the model based definition of the workpiece; and generate further instructions for at least one further machine of the manufacturing chain based upon the differences.

Abstract: An additive manufacturing apparatus including a scanner for directing a laser beam on to layers of flowable material to selectively solidify the material to form an object in a layer-by-layer manner. The scanner includes an optical component operable under the control of a first actuator to reflect the laser beam over a first range of angles in a first dimension and the or a further optical component operable under the control of a second actuator to reflect the laser beam over a second range of angles in the first dimension, wherein the second actuator provides a faster dynamic response but a smaller range of movement of the laser beam than the first actuator.

Abstract: An additive manufacturing apparatus including a build chamber containing a support for supporting a material bed, a layering device for forming layers of the material bed, a laser or electron beam source for generating a laser or electron beam, a device for steering the laser or electron beam to solidify selected areas of each layer to form a part and a microwave or radio wave source controllable to generate a microwave or radio wave field to differentially heat the material bed based upon the selected areas.

Abstract: This invention concerns a selective solidification apparatus including a build chamber, a build platform lowerable in the build chamber, a wiper for spreading powder material across the build platform to form successive powder layers of a powder bed, an energy beam unit for generating an energy beam for consolidating the powder material, a scanner for directing and focussing the energy beam onto each powder layer and a processor for controlling the scanner. The processor is arranged to control the scanner to scan the energy beam across the powder bed to consolidate powder material either side of the wiper when the wiper is moving across the powder bed and to scan the energy beam across at least one of the powder layers during two or more strokes of the wiper across the powder bed.

Abstract: An error correction method for coordinate positioning apparatus is described. The method comprises (i) taking a first data set comprising one or more first data values, each first data value describing a position on the surface of a first object, (ii) taking a second data set comprising one or more second data values, each second data value describing a position on the surface of the first object, and (iii) calculating an error map comprising one or more error values, each error value describing a positional difference between the surface as described by the first data set and the surface as described by the second data set. The surface normal of the first object is known at each position described by each first data value and step (iii) comprises calculating each error value by determining the positional difference substantially in the direction of the known surface normal.

Abstract: Surgical apparatus is described that includes a surgical robot having a moveable arm for carrying a surgical tool. The apparatus also has x-ray imaging apparatus that includes at least one of an x-ray source and an x-ray detector. The moveable arm of the surgical robot is configured to carry at least one of the x-ray source and the x-ray detector. In this manner, the surgical robot can be used to perform x-ray imaging to allow patient registration. Methods of using the apparatus are also described.

Abstract: An additive manufacturing machine for building objects by layerwise melting of powder material includes a build chamber containing a build platform, a powder dispenser depositing the powder material in layers across the platform, a high energy beam selectively melting powder material in each layer and a control device controlling a property of the powder material given by build particles in the powder material below a specified upper particle size limit. A method includes controlling a property of the powder material given by build particles below a specified upper particle size limit. A method carries out successive builds, wherein in-between the builds, particles are added to or removed from the powder material to effect a property of the powder material given by build particles below a specified upper particle size limit. Further, adding or removing particles ensure that a sufficient proportion of micro build particles are present in the powder.

Abstract: An additive manufacturing apparatus for building objects by layerwise consolidation of material. The apparatus includes a build chamber containing a working area, a plurality of high energy beams for consolidating material deposited in the working area in layers and an optical unit for controlling transmission of the high energy beams onto material in the working area. The optical unit includes a plurality of independently controllable optical elements each optical element for controlling transmission of at least one of the high energy beams onto the material in the working area, the optical unit movable in the build chamber.

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 manufacturing at least one component in at least one component area on a substrate using a machine that has a substrate processing part relatively moveable with respect to the substrate. The method includes, at least when the substrate processing part and substrate are in a positional relationship in which the substrate processing part can process the at least one component area on said substrate, measuring the position of the substrate processing part relative to the substrate, by reading at least a first metro logical scale provided by the substrate.

Abstract: A coordinate positioning apparatus including: a coordinate positioning machine having a measuring probe for interacting with an artefact to obtain measurement data regarding the artefact. The measuring probe and artefact are moveable relative to each other in at least one machine degree of freedom. The apparatus further includes a hand-held device, moveable in free-space in a plurality of device degrees of freedom, for controlling movement of the measurement probe relative to the artefact. The hand-held device includes at least one motion sensor for sensing movement of the hand-held device in free-space. The apparatus is configured such that the relative movement of the measurement probe and artefact is controlled by said movement of the hand-held device in free-space.

Abstract: Apparatus for a co-ordinate positioning machine is described that comprises an articulating probe head for supporting a measurement probe. The articulating probe head comprises at least one electric motor. Heating means are provided for generating heat in the articulating probe head. The heating means may be the motors or discrete heating elements. Temperature sensing means, such as one or more temperature sensors, is also provided for determining the temperature at the articulating probe head. The apparatus allows the temperature of the articulating probe head to be controlled.

Abstract: A rotary gas bearing is described that comprises a first part rotatable relative to a second part. The first part comprises a support member and a first portion and a second portion attached to the support member. The first portion comprises a first bearing surface and the second portion comprising a second bearing surface. Both the first portion and the second portion are attached to the support member by screw thread connections. The second part may comprise complimentary bearing surfaces. Epoxy may be used to fix the first and/or second portions to the support member. A method of determining the bearing working gap by measuring gas flow through the bearing is also described.

Abstract: An error correction method for coordinate positioning apparatus is described. The method comprises (i) taking a first data set comprising one or more first data values, each first data value describing a position on the surface of a first object, (ii) taking a second data set comprising one or more second data values, each second data value describing a position on the surface of the first object, and (iii) calculating an error map comprising one or more error values, each error value describing a positional difference between the surface as described by the first data set and the surface as described by the second data set. The surface normal of the first object is known at each position described by each first data value and step (iii) comprises calculating each error value by determining the positional difference substantially in the direction of the known surface normal.

Abstract: A method and apparatus for measuring a surface using a surface sensing device mounted on a scanning head on a member of a coordinate positioning apparatus. The coordinate positioning apparatus may be operated to produce relative movement between the scanning head and the surface profile and the scanning head includes a drive for producing rotational movement of the surface sensing probe about one or more axis. The coordinate positioning apparatus is driven to provide relative movement between the member and the surface profile in a circular path and the scanning head is driven to move the surface sensing device about said one or more axes, such that the surface sensing device maintains a nominally constant lead angle. The motion of the coordinate positioning apparatus and scanning head is synchronous.

Abstract: A surface sensing device for use in position determining apparatus has an elongate stylus with a tip for scanning the surface of a workpiece to be measured. Lateral displacements of the stylus tip are detected by a light beam which passes along the stylus from a light source to a retroreflector. This reflects the beam back via a beamsplitter to a position sensitive detector. The stylus is mounted for longitudinal displacement on a carriage. The longitudinal displacement is measured by another light beam projected by the beamsplitter onto a second position sensitive detector.

Abstract: A surface sensing device for use in position determining apparatus has an elongate stylus (74) with a tip (82) for scanning the surface of a workpiece to be measured. Lateral displacements of the stylus tip are detected by a light beam which passes along the stylus from a light source (66) to a retroreflector (78). This reflects the beam back via a beamsplitter (70) to a position sensitive detector (76). The stylus is mounted for longitudinal displacement on a carriage (72). The longitudinal displacement is measured by another light beam projected by the beamsplitter (70) onto a second position sensitive detector (84).