Abstract: An additive manufacturing powder recirculation apparatus including: a powder recirculation loop having: an inlet for receiving powder from an additive manufacture apparatus; an outlet for supplying powder to the additive manufacture apparatus; and a powder flow path extending between the inlet and outlet. A diverter valve in the powder flow path is configured to selectively place the powder flow in fluid communication with either the downstream powder recirculation loop or a hopper outside of the powder recirculation loop.

Abstract: A coordinate positioning machine includes a drive frame and a metrology frame. The drive frame includes a drive arrangement for moving a structure around a working volume of the machine. The metrology frame includes a metrology arrangement for measuring the position of the structure within the working volume. The metrology arrangement is a hexapod metrology arrangement and the drive arrangement is a non-hexapod drive arrangement. The metrology frame has a coefficient of thermal expansion that is lower than that of the drive frame. The drive frame is coupled to the metrology frame via a coupling arrangement which prevents at least some distortion associated with any extra thermal expansion and contraction of the drive frame from being transferred to the metrology frame. The drive arrangement moves the structure around the working volume, and the metrology arrangement measures the position of the structure within the working volume.

Abstract: A shadow-cast encoder apparatus includes a scale and a readhead. The readhead includes at least one electromagnetic radiation source for illuminating the scale in order to produce a shadow-cast fringe pattern at a detector configured to detect the shadow-cast fringe pattern. The encoder apparatus can be configured so as to suppress the total harmonic distortion of the fringe pattern, e.g. such that the total harmonic distortion of the fringe pattern is not more than 6%.

Abstract: A method of aligning an on-axis melt pool sensor in an additive manufacturing apparatus. The method includes scanning a first laser beam along a first scan path across a working surface using a first optical train to generate a melt pool along the first scan path and scanning a field of view of an on-axis sensor along a second scan path across the working surface using a second optical train for steering a second laser beam. The first and second scan paths intersect. An adjustment to be made to an alignment of the field of view of the on-axis sensor with an optical axis of the second optical train is determined from a variation in the signal generated by the on-axis sensor as the field of view is scanned along the second scan path.

Abstract: This invention concerns an additive manufacturing apparatus for building objects by layerwise consolidation of material. The apparatus includes a build chamber containing a working area, a high energy beam for consolidating material deposited in the working area in layers and a flow device for generating a gas flow across at least a part of the working area from a gas inlet to a gas outlet. The gas inlet and gas outlet are arranged to be movable within the build chamber.

Abstract: A surface finish stylus and associated methods for a multi-directional scanning probe the stylus having an elongate stylus shaft having a longitudinal axis and one or more contact elements protruding from the elongate shaft for contacting a surface to be measured. The one or more contact elements are configured to enable measurement of surface finish during motion of the stylus shaft relative to a surface along a measurement direction that is non-parallel to the longitudinal axis. The multi-directional scanning probe may be carried by a coordinate measuring machine or machine tool.

Abstract: A method of calibrating an ultrasound probe having a coupling element for engaging the surface of an object to be inspected, in which the ultrasound probe and a calibration artefact are provided on a positioning apparatus having at least one axis about which the relative orientation of the ultrasound probe and calibration artefact can be changed, the method including, in any suitable order: i) for a plurality of different relative orientations between the ultrasound probe and the calibration artefact about the at least one axis, measuring the signal received by the ultrasound probe; and ii) from the measurements, determining at least one calibration parameter which is indicative of at least one axis of optimum signal of the ultrasound probe, and recording the at least one calibration parameter for subsequent use.

Abstract: A method of powder bed fusion additive manufacture includes forming a component in a powder bed in a layer-by-layer process. The method may include sintering, without melting, selected regions of powder with an energy beam to form at least one support adjacent to the component; and melting further selected regions of the powder bed with an energy beam to form a component by layer-by-layer melting of material. The method may include directing an energy beam at selected regions of powder to form a friable support, the friable support including bonded powder which act as a solid and provide compressive support; and melting further regions of the powder bed with an energy beam to form a component by layer-by-layer melting of material.

Abstract: A method controls an additive manufacturing apparatus, in which an object is built by consolidating material in a layer-by-layer manner. The method includes receiving commands to be executed by the additive manufacturing apparatus to cause the additive manufacturing apparatus to carry out a build of an object, wherein each command includes an identifier identifying a time during the build at which the command is to be executed, and executing each command on the additive manufacturing apparatus in accordance with the time identified by the associated identifier. Further, an apparatus and a data carrier carry out the method.

Abstract: A non-Cartesian coordinate positioning machine that includes an extendable leg assembly for positioning a component such as a measurement probe within a working volume of the machine. The extendable leg assembly includes a first member and a second member which move relative to one another when the extendable leg assembly changes length. The first member including an axial arrangement of magnets forming part of a linear motor for extending and retracting the extendable leg assembly, and at least one resilient member for absorbing at least some of any axial thermal expansion or contraction of the magnets in use.

Abstract: A non-Cartesian coordinate positioning machine is provided that comprises an extendable leg assembly for positioning a component such as a measurement probe within a working volume of the machine, and a constraint member associated with the extendable leg assembly for providing a predetermined part of the extendable leg assembly with substantially a same orientation relative to gravity for a same position of the component within the working volume. In a preferred embodiment, the orientation relative to gravity is maintained substantially constant, so that a plane defined by the predetermined part is substantially aligned with gravity, as the component is moved around the working volume.

Abstract: A touch trigger probe interface for a machine tool is described that includes a probe communication portion for receiving probe event information from a touch trigger probe. A machine tool communication portion is also provided for outputting probe event information to a numerical controller of the machine tool. The machine tool communication portion outputs the probe event information as digital data packets, for example over a digital data bus. The digital data packets may include a time stamp and/or the touch trigger probe interface may receive timing information from the machine tool. A touch trigger probing system and a machine tool system including the probe interface are also described.

Abstract: An additive manufacturing apparatus including a build chamber, build platform lowerable in the chamber so layers of flowable material can successively form across the platform, laser for generating a laser beam, scanning unit for directing the laser beam onto each layer to selectively solidify the material and a processor for controlling the scanning unit. The processor controls the scanning unit directs the laser beam to solidify a selected area of material by advancing the laser beam many times along a scan path. On each pass, the laser beam solidifies spaced apart sections of the scan path, each subsequent pass solidifying sections that are located between sections solidified on a previous pass. The processor controls the scanning unit to direct the laser beam to solidify selected area of material by solidifying sub-millimetre sized sections of non-continuously area and in an order such that consecutively solidified sections are spaced apart.

Abstract: A hard-wired measurement device is mountable within an enclosure of a computer-controlled machine tool. The device includes a measurement sensor for measuring objects, such as tools, within the machine tool enclosure and a hard-wired interface module for providing an electrical connection via one or more wires with an associated external interface located outside of the machine tool enclosure. The device further includes a wireless communications module that enables wireless communication with an associated wireless device, such as a spindle probe, located within the machine tool enclosure.

Abstract: A powder bed fusion apparatus and method includes a build platform for supporting a powder bed onto which layers of a powder can be deposited, a scanner for scanning an energy beam over each layer to fuse selected regions of the powder bed and a gas flow circuit for passing a flow of gas over the powder bed. The gas flow circuit includes a filter assembly including a filter housing through which the gas flows, the filter housing containing a granulate, preferably powder, filter medium for filtering particles from the gas flow. The powder filter medium may correspond to powder used to form the powder bed such as being of the same material as the powder used to form the powder bed.

Abstract: A manufacturing system includes: a coordinate positioning machine having a structure moveable within a working volume of the machine, a drive arrangement for moving the structure around the working volume, and a positioning arrangement for determining the position of the structure within the working volume with a first accuracy; and a metrology arrangement to which the machine is removably couplable, such that when the machine is coupled to the metrology arrangement, with the structure being moved by the drive arrangement, the metrology arrangement is able to measure the position of the structure with a second accuracy that is higher than the first accuracy.

Abstract: Neurosurgical apparatus has a guidance device having a guide tube and a neurosurgical instrument for insertion into the guide tube. The inner surface of the guide tube is arranged, for example profiled, to at least partially engage the outer surface of the neurosurgical instrument when inserted therein. The guide tube thus guides the neurosurgical instrument along a predefined path through the guide tube. At least one of the guidance device and the outer surface of the neurosurgical instrument are configured to provide a fluid return path for carrying any fluid displaced from within the guide tube during insertion of the neurosurgical instrument into the guide tube. A seal may also be provided for sealing the fluid return path.

Abstract: A coordinate positioning apparatus having a load bearing structure. The load bearing structure has at least one elongate corner piece providing at least two bearing surfaces, one on each side of the corner, for a carriage moveable along the load bearing structure, and at least one piece of sheet material which extends along the at least one elongate corner piece and provides at least one load bearing facet.

Abstract: An incremental encoder apparatus including: a scale including a series of periodic features defining an optical incremental scale, and at least one magnetic reference mark; and a readhead. The readhead includes at least one incremental sensor configured to detect light from the optical incremental scale and to output at least one signal dependent thereon, and at least two analogue Hall sensors, each including at least two output terminal pairs, and each configured to switch repeatedly between each output terminal pair so as to reduce any inherent offset in the output of the analogue Hall sensor. The apparatus is configured to determine the presence of the reference mark from the outputs of the at least two analogue Hall sensors.

Abstract: An ultrasound probe is described that comprises a transducer for transmitting and receiving ultrasound. The probe also includes a coupling element, such as a spherical ball of self-lubricating or hydrogel material, for contacting and acoustically coupling to an object to be inspected. The ultrasound probe also includes an analyser that is arranged to analyse the ultrasound signal received by the transducer and thereby determine if there is contact between the coupling element, and the surface of an object. The probe can thus be used for internal (ultrasound) inspection of objects as well as measuring the position of points on the surface of the object. The probe may be mountable to a coordinate measuring machine or other moveable platforms.