GB2510965A

GB2510965A - Method of producing a shaped component

Info

Publication number: GB2510965A
Application number: GB1322296.3A
Authority: GB
Inventors: Arnaud Brandt
Original assignee: Hexcel Composites SARL
Current assignee: Hexcel Composites SARL
Priority date: 2012-12-21
Filing date: 2013-12-17
Publication date: 2014-08-20
Also published as: CH707395B1; BE1021764B1; LU92341B1; GB201223303D0; IE20130388A1; GB201322296D0; CH707395A2

Abstract

In a method of producing a component a movable cutting device cuts material and a movable measurement device measures the cut material. Parameters of the cut material are recoded and a comparator compares the measured parameters with desired parameters. If the measured parameters deviate from the desired parameters by a defined margin, the cutting device position and activation is modified to meet the desired parameter within the defined margin. The cutting device may comprise a machine tool, laser cutter, water jet, knife, oscillating saw or hot wire cutter, and is preferably movable in 3 dimensions. The cutting and measuring devices may be mounted on the same movable support and may be used simultaneously. The measuring device may be wireless. The method may be used when producing articles from a honeycomb structure or a composite material. Also disclosed is a method of homing a measuring device in which parameters from the measuring device are recorded while positioning the measuring device towards a reference point. A change in the measured parameter is detected by a detector and the position of the measuring device is referenced to the position of the reference point. This process may be repeated in an orthogonal plane.

Description

METHOD OF PRODUCING A SHAPED COMPONENT

The present invention relates to a method of producing a shaped component, particularly but not exclusively to a honeycomb component or any shaped component produced from a soft deformable material for use as a core component in a composite structure.

S BACKGROUND

Honeycomb core material is a material composed of hollow cells of hexagonal cross section. The honeycomb shape facilitates a reduction in material used to form a composite structure of a specified volume and therefore it is typically of an exceptionally low weight. Honeycomb materials exhibit excellent out-of-plane compression and out-of-plane shear properties with minimal density.

Because of these properties honeycomb is commonly used as a core material in laminate composite structures. Honeycomb or other core materials are also used to increase the stiffness of a laminate by increasing the thickness of the laminate. This provides a significant increase of stiffness without adding significant amounts of weight. Core materials are almost always very low density materials and are typically inserted between layers of a rigid material such as a fibre reinforced polymer, this is often referred to as a sandwich structure.

Honeycomb cores that are used in sandwich structures are usually made from a range of materials; these include paper and card for low strength and stiffness in low load applications, aluminium, aramid and thermoplastics for high strength and stiffness applications. The honeycombs used in extremely lightweight components for aircraft structures are typically made from aluminium or aramid paper.

Honeycomb can be produced in a multistage process whereby sheets of material are printed with parallel strips of resin and arranged to form a stack. The stack is pressed and heated to cure the adhesive) then expanded into a block. In the case of aramid paper honeycombs) the block is dipped in a tank of resin, drained, then cured in an oven to improve mechanical properties and/or improve its flame retardancy. Once the dipping resin has cured) the block has sufficient strength to be sliced into sheets of the final thicknesses required. Honeycomb can also be formed by the corrugation method, whereby successive sheets are corrugated by passing through rollers) and then alternately assembled into stacks and bonded with adhesives. Honeycomb can also be produced by extruding thermoplastics into a honeycomb shape.

Honeycomb sheets can be processed into both flat and gently curved shapes) and can be made to conform to curves without excessive mechanical force or heating. Nomex (TM) honeycomb can be heat-formed by deforming a sheet of honeycomb into a mould and heating to approximately 210CC and cooling whilst maintaining the material in the desired shape. This method is only suitable for simple curved geometries and thin sheets of honeycomb. Further complications arise as honeycomb exhibits anticlastic curvature when bent, and can be difficult to manipulate into a mould without damage. Furthermore, honeycomb is highly anisotropic and resists compression only in the direction parallel to the axis of the hollow cells. Bending or heat-forming changes the alignment of the honeycomb cells from a parallel arrangement to a radial arrangement, which may be undesirable depending on the final use of the part.

It is necessary to machine honeycomb to achieve complex geometries such as compound curves, curves with small radii, irregular shapes or shapes of large thickness. The machining of complex shaped components from honeycomb or other soft deformable materials can be problematic, especially for three dimensional shapes that are difficult to support during machining. The hollow tubular cells of the honeycomb core are not sufficient in hardness and strength to withstand being displaced or bent by the cutting tool. Thus the cell walls in the cut surface result in inappropriate deformation such as crumpling, collapsing, burring, etc. The accurate cutting of such materials requires frequent measurement in a non-displaced state, this helps to prevent wastage from the over cutting' of a component. Furthermore the hollow cellular nature of expanded honeycomb increases the difficulty of producing accurate automated measurements. The necessity to make frequent and difficult measurements results in an increase of production time.

When cutting deformable soft materials with automated numerically controlled cutting apparatus, integrated position tracking of the cutting tool position can be unreliable as a measure of part dimension because of the displacement of the material when contacted by the cutting tool.

Therefore auxiliary measurement is required. Honeycomb is anisotropic so it is difficult to predict the extent of deformation that occurs. It therefore becomes necessary to interrupt machining at specified intervals to measure the dimensions of the component using a measurement device that is separate to the NC cutting apparatus. When measuring it is necessary to withdraw the tool head, so that the material restores its un-deformed position. The interruption of machining for measurement increases production time and therefore increases the cost of production.

The present invention aims to solve the aforesaid problems and/or to provide improvements generally.

SUMMARY OF INVENTION

According to the invention, there is provided a method and an apparatus as defined in any one of the accompanying claims.

In an embodiment of the invention, there is provided a method of producing a component, comprising providing a movable cutting device for cutting material; a movable measurement device for measuring the cut material; recording means for recording measured parameters of said cut material; a comparator for comparing the measured parameters with desired parameters; and a control means for controlling the position and activation of the cutting head and the position of the measurement device, wherein the method comprises the steps of; a) positioning the cutting device to cut the material to predetermined dimensions; b) positioning the measurement device to measure one or more parameters of said cut material; c) recording the measured parameters; d) comparing the measured parameters with the desired parameters; and e) following the above, if the measured parameters deviate from the desired parameters by a defined margin, the control means position the cutting device and activate the cutting device to cut the material to meet the desired parameter within the defined margin, whereupon the cutting head is positioned to an alternative position.

Advantageously the present invention provides a method and apparatus whereby the measurement device and its operation are integrated with a cutting device. This integration reduces input and production time, thereby reducing the cost of production. In an embodiment, the present invention provides a method of utilising the measured and desired parameters to control further cutting of the cut material, advantageously this provides further reductions of user input and production time.

In a preferred embodiment the output of the measuring device is transmitted wirelessly to the recording means. This eliminates the need for measurements to be manually read from the measuring device by the operator.

In another embodiment of the invention the control means for controlling the position of the measurement device and/or cutting device is calibrated, "homed" or zero-ed in relation to a fixed reference point.

"Homing" is defining a position of the cutting or measuring device in relation to a reference point having a position that is known in three dimensional space. This allows the position and motion of the cutting device to be defined as vectors in relation to the reference point. Usually it is necessary to home the measurement or cutting device prior to use to calibrate the positioning coordinates which are used by the control means.

According to a further invention, there is provided a method of homing a measurement device, comprising providing: a measurement device on a moveable support; a reference point of known location, a recording means for recording a parameter(s), a detector and; a control means for controlling the position of the measurement device, wherein the method comprises the steps of: a) positioning the measurement device towards a reference point and using the recording means to record a parameter(s); b) using the detector to detect a change in the parameter(s) as a result of the position of the measurement device locating the reference point; c) using the control means to reference the current position of the measurement device in at least one axis to the known location of the reference point; d) optionally repeating the above steps with a reference point in a plane orthogonal to the original plane to obtain position for other axes.

In this way the position of the measuring device can referenced to a known location in three dimensional space.

In a further embodiment, the method of producing a component may comprise homing steps preceding step a) orb) comprising providing: a reference point of known location, and a detector for detecting a measured a parameter(s), wherein the method further comprises the steps of: a) positioning the measurement device towards a reference point; b) detecting a change in the measured parameter(s) in response to the measurement device locating the reference point; c) the control means referencing the current position of the measurement device in at least one axis to the known location of the reference point to home the control means; d) optionally repeating the above steps with a further reference point in a plane orthogonal to the original plane to obtain position for other axes.

In an alternative embodiment, the reference point can be any three dimensional object with a feature that varies in one dimension, for example a face plate with a hole, notch or groove that marks the centre of the reference point. The position of the reference point must be known in at least one axis. Preferably the reference point is capable of being repositioned into at least one alternative orientation to the original position. By repositioning the reference point a reference position for the measuring device can be obtained for further axes if required.

In an alternative embodiment the measurement device comprises a probe with a tip of known dimensions which is connected to the measurement device. Preferably, the shape of the tip corresponds to the reference point. Preferably the tip is spring loaded so as to maintain contact with the reference point. When the tip is displaced, the measuring device measures the displacement as a parameter that is recorded by the recording means. For example, as the measuring device is brought towards the reference point an initial displacement of the probe tip is recorded as it makes contact with the face of the reference point. Once the measuring device is correctly aligned to the hole of the reference point, the tip will displace into the hole. When this occurs the recording device will record a different displacement value which is detected by the detector. The position of the reference point in at least one axis can then be referenced to the current position of the measuring device. Where necessary to obtain a reference position for further axes, the process can be repeated with an additional reference point in a different orientation to the first reference point. Alternatively the reference point can be moved into an alternative orientation. Preferably the additional reference orientations are orthogonal to the original orientation.

In an embodiment, the measurement device comprises a probe capable of detecting a displacement along its axis and/or perpendicular to it. The detection of a change of displacement perpendicular to the probe axis may be used to home the measuring device in an axis perpendicular to the probe axis.

Alternatively the probe may be of known length. When initial contact is made with the reference point or a reference surface, the length of the probe may be used with the known reference position to home the measurement device for the axis parallel to the probe.

In alternative embodiment the tip may comprise a cone. When a cone is located over a reference hole, the position where maximum displacement (e.g. in the Z direction) into the reference hole occurs when the cone is perfectly centred over the reference point. The X and V position can then be recorded. Moving the probe in either the X or V direction will result in an associated displacement in the Z direction as the cone moves out of the centre location of the reference hole. The resulting change in the Z direction is dependent on the distance moved in the X or V direction and the angle of the conical surface of the cone to its axis. Trigonometry can then be used to calculate the Z position, negating the need to reposition the reference point.

The detector may comprise a software implemented algorithm that analyses the variation of the measured parameter with time. When the measurement device locates the reference point, there is an associated change of the measured parameter which is detected by the detector. Preferably the detector operates in real time as the recorded parameter values are generated.

Advantageously the wireless transmission of the output of the measuring device overcomes any incompatibility of auxiliary wires with the moveable support, and enables the measurement device to be mounted on the same moveable support as the cutting device. Thus reducing production time and saving expense.

In an embodiment the cutting device is mounted on any moveable support capable of moving the cutting device in at most 6 degrees of freedom (x, y and z and 3 axes of rotation). Examples of such systems include robot arms) bridge or gantry systems.

The moveable support is controlled by the control means and serves to move the cutting device in a predetermined trajectory, thereby cutting the material into a required shape. The moveable support is preferably operated by computer control and controlled by the control means using inputs provided by the user.

In an embodiment the measuring device is also mounted on a moveable support capable of moving the measuring device in at most 6 axes. Examples of such systems include robot arms, bridge or gantry systems. Preferably the measurement device is mounted with the cutting device on the same moveable support.

The cutting device may be any device mountable to a moveable support that is capable of abrading, cutting, burning or eroding the material. In an embodiment the cutting device comprises a, laser cutter, water jet, knife, oscillating saw, hot wire cutter or preferably a machine tool.

The material may comprise a honeycomb structure or polymer foam; wherein the honeycomb structure may comprise aluminium, aramid paper (e.g. Nomex tm) cellulose paper, or thermoplastic polymers such as polypropylene. The polymer foam may for example comprise polyvinylchloride (PVC), polyurethane (Pu), polystyrene (PS), polyethyleneimine (PEI) or styrene-acrylonitrile (SAN).

The measurement device may comprise a digitally operated measuring system; which optionally may be a mechanical or a contactless measuring system. Exemplary mechanical measurement devices include but are not limited to gauge comparators, callipers, depth gauges, linearly variable displacement transducers and all other mechanical probes known in the art. An exemplary mechanical measurement device is the Mitutoyo Gage Block Comparator GBCD-250 (Mitutoyo Corporation). Exemplary contactless measurement devices include, but are not limited to red or white light LED or LASER systems, or ultrasonic, inductive or capacitive distance sensors.

In an embodiment the measurement device is used with the cutting device for the simultaneous cutting and measuring of the material. To achieve this, the measuring and cutting devices are mounted on the same moveable support with sufficient spacing so that the contact of the cutting device does not deform the material at the point of measurement. This spacing will depend on the

S

type of cutting tool and material used, and can be determined by observing the radius of deformation during cutting.

In an embodiment multiple measurements of a parameter are performed at each measured point on the surface of the material. The mean measured parameter is only recorded on the recording means if the measurements are suitably similar or a within a defined margin. A defined margin' or suitably similar' is where all of the measurements made for a point have a range wherein the range does not exceed 1j10tb of the mean of those measurements.

The term measured parameters' refers to the outputs of the measuring device that are recorded on the recording means. The measuring device measures the locations of points of the surface of the cut material. Multiple points can be used to derive dimensions of the cut material. The dimensions may be in the form of vectors from a common or instantaneous floating reference point to points on the surface of the cut material, a linear dimension of the cut material between two points e.g. a secant/chord or thickness between two points on the surface of the cut material, or a nonlinear dimension such as an arc or trajectory on the surface of the cut material. The points in combination, may also approximate surface nodes, point clouds, splines or any other dataset capable of describing, approximating or being converted (e.g. by interpolation) into a volume, surface or shape.

The desired parameters refer to an input provided by the user. This may be inputted in the form of splines, volumes, surfaces, trajectories, individual points or vectors, and may be provided as a data file. Such data maybe created via a CAD program, manually by the user or derived from other software pertaining to the handling such data types.

The defined margin refers to an acceptable tolerance between the measured parameters and the desired parameters of the cut material. The defined margin may be a global parameter that defines a manufacturing tolerance applicable to all surfaces (for example as a percentage of the measured dimension)) edges and/or vertices of the produced component or it maybe inputted as an array of parameters specific to each dimension) edge) face or vertices of the desired shape input, or groups thereof. This is particularly advantageous if the overall shape of the component requires a higher precision for certain sections than others.

The recording means may be any apparatus capable of recording or storing data obtained from the measuring device. The recording means may comprise computer software necessary for the transmission of an output from measurement device to a storage device. A storage device may comprise for example, a hard disk or a personal computer. The recording means may also convert the output of the measuring device to a value that corresponds to a physical unit using calibration data, either prior to or following storage of the data.

In an embodiment the comparison of the measured parameters with the desired parameters may be a subtraction of the measured parameters from the desired parameters plus or minus the defined margin. If the any of the measured parameters are greater than the desired parameter plus the defined margin) then the cut material is too large) i.e. under-cut', and further cutting with measurement for the under-cut section is required. If all of the measured parameters are within the desired parameter plus or minus the defined margin, then the cut material is considered a produced component of correct dimensions. If the any of the measured parameters are smaller than the desired parameter minus the defined margin, then the part is deemed to have been over-cut' and the material will have to be discarded and the process restarted. In an embodiment, the comparator is an algorithm implemented with software.

In an alternative embodiment the measuring parameters are compared with the desired parameters during the cutting of the material. If a section of the cut material cut over-sized then the control means can interrupt the cutting tool trajectory to follow a modified trajectory, re-cutting the over-sized section. Once the means for comparing has determined that the over-cut section has then been re-cut within the defined margin of the desired parameters the cutting tool resumes its original trajectory.

The control means may convert the desired parameters, either directly or through converting to intermediary data file types, to a trajectory or tool path necessary for cutting the material to the desired shape. Alternatively the desired parameters may be an inputted trajectory or tool path inputted by the user. Wherein the control means uses the measured parameters to calculate the necessary trajectory for correcting or restarting cutting. In an embodiment the control means uses a numerical control (NC) system which is well known to the art. In an embodiment a control means affects the position of the moveable support for the cutting tool and/or the measuring device.

It is envisioned that in an embodiment of the invention the means for controlling the position and operation of both the cutting tool and the measuring device is performed by software implemented as a computer program. In another embodiment of the invention the measured parameters, inputs, comparing of parameters is performed by software implemented as a computer program. In an embodiment, all software operations are handled by one computer program, or a plurality of programs with shared inputs and outputs.

DETAILED DESCRIPTION

The invention will now be clarified by way of example only and with reference to the accompanying drawings in which: Eigure 1 discloses a flow diagram of an embodiment of the present invention; Figure 2 discloses a flow diagram of an alternative embodiment of the present invention; and FigureS discloses a flow diagram of a further embodiment of the present invention.

The process diagram 30) of Figure 1 shows the process (30) for the production of a component (14) from a material (32). A user provides the necessary inputs (2), which may comprise a NC trajectory (22), a desired shape of the produced component (24) and a defined margin (26). The NC trajectory may for example be automatically derived from the desired shape input thereby reducing operator burden and further increasing automation of the component production. Alternatively the NC trajectory may be a separate direct input, or automatically derived from an input different to the desired shape input. The defined margin may be a global parameter that defines a manufacturing tolerance applicable to all surfaces, edges and vertices of the produced component or it may be inputted as an array of parameters specific to each edge, face or vertices of the desired shape input, or groups thereof.

The next step in the method (30) consists of the cutting of the material by the moveable cutting device (4). A control device moves the moveable support and cutting device in accordance with an inputted or calculated NC trajectory thereby cutting the material to a shape that corresponds to the desired shape of the produced part.

The measurement device then measures dimensions of the cut material (6) which are transmitted to a recording means (8). The measuring device is mounted on a moveable support, which in a preferred embodiment is the same moveable support onto which the cutting device is mounted. The moveable support and therefore the position of the measuring device is preferably controlled by numerical control, but optionally can be controlled manually. The measurement of the dimensions is performed by locating the measurement device at positions which correspond to points on the surface of the cut material. These locations may preferably be calculated automatically from the desired shape input provided by the user, or provided as a separate input by the user. In an embodiment, the measurement device will move to multiple locations and measure the position of the surface of the cut material at each location. The measured surface positions correspond to dimensions of the cut material. Sufficient dimensions must be measured of the cut material to be representative of its actual size, it follows that the number of dimensions will increase with increasing complexity of the desired shape, furthermore, if certain regions of the produced component require a higher tolerance then increased dimension measurements in that region may be required. In an embodiment multiple measurements of a parameter are performed, and the measured parameter is only recorded on the recording means if the measurements are suitably similar. The recording of a measured parameter is performed by transmitting measurement data from the measurement device to recording means. Transmission is preferably performed by wireless methods, but can also be performed by wired methods which are well known to the art.

The recording means may comprise any device capable of storing data. The recording device creates an array of measured parameter during cutting, once measurement is completed the means for comparison compares this to a corresponding array dimensions derived from desired parameters.

The recorded measured parameters are then compared against the desired parameters (10). In its simplest embodiment this may be a straightforward subtraction of the measured parameters from the desired parameters. The subtraction result is then compared to the relevant defined margin, if the cut material has been cut with dimensions that exceed the desired margin and are smaller than the desired parameters i.e. the material has been over-cut' then it is likely the material will have to be discarded and the process restarted. If the measured parameters exceed the defined margin and are larger than the desired parameter then the cut material will require further cutting until it is within the defined margin of the desired parameters (16). If measured dimensions exceed the desired parameters and the defined margin the cut material has been under-cut'. In this instance the necessary further cutting by the cutting device may be calculated and then executed using the result of the comparison of the measured parameters and the desired parameters as the difference corresponds to the amount of material that is to be removed. The difference between parameters can form the basis for calculations of a new NC trajectory for the cutting device (18). If the cut material is within the defined margin for all measured parameters (12) then the cutting of the part is deemed to be complete (14). Optionally at this stage the recorded measured parameters can be associated with an identifying code for the produced component. This can be issued as a document or stored as an electronic data file to be used as a certificate for quality control purposes, listing an array of the measured parameters and stating the produced component has been measured and conforms to a defined margin.

It is envisioned that for certain embodiments of the invention, one or more of the above steps can be implemented by computer software as appropriate.

S Figure 2 illustrates an alternative process (40) for the production of a component (50) from a material (32), wherein a user provides the necessary inputs (2), which may comprise desired parameters (24), a defined margin (26) and a NC trajectory (22) which may also be derived from the desired parameters.

The next step in the method comprises the cutting of the material by the cutting device (42). The cutting device position is controlled by the control means and follows a predetermined trajectory that positions the cutting device to cut the material to the desired parameters. Thus cutting the material to a shape that corresponds to the desired shape of the produced part. The measuring device is also controlled by the control means to perform measurements of the cut part simultaneously with the cutting (44).

The comparator compares the measured parameter with the desired parameter an individual parameter or a sample of parameters corresponding to a surface vertex, edge or region of the cut part with a corresponding desired parameter or parameters for that point or region (46). If the measured parameter is smaller than the corresponding desired parameter minus the defined margin, then the part has been over-cut in the region surrounding that measured point, and must be discarded (not shown). If the measured parameter is within the corresponding desired parameter plus or minus the defined margin, then the part is of suitable size in that region and the cutting device continues along its original trajectory (50). If the measured parameter is greater than the corresponding desired parameter plus the defined margin, then the part is under-cut at that section or point (52). In this instance the difference between the measured parameter and the desired parameter is used to calculate a modified trajectory of the cutting tool and re-cut the under-cut section (54). The re-cutting of the under-cut region is performed with continuing measurement of the under-cut region. When the relevant region is no longer under-cut the cutting tool resumes its original trajectory (50), until the end of the trajectory is reached and the part cut material conforms to the desired parameters of a produced component (58).

The process diagram ($0) of Figure 3 shows the process of homing a measurement or cutting device.

This process can be implemented as part of the process of cutting a component or alternatively, as is described now, it can be implemented independently.

The process consists of the following steps: a positioning step (82) where the measuring device is positioned towards the reference point; a measurement step (88) where a measured parameter from the measurement device is recorded by the recording device; a detection step (90) where a change in the measured parameter is detected by the detector; a referencing step (92) where the position of the measuring device referenced to the position of the reference point; and a final step (94) where the prior steps are repeated if required, with a reference point in a different orientation.

During the positioning step (82) the measurement device is moved towards a reference point, this can be done either automatically or manually by the operator. Preferably the measurement device is moved towards face plate of the reference point, before the hole of the reference point is located under fine control.

In the measuring step (88), the measurement device measures a parameter which is transmitted to the recording device. The recorded parameter may, for example, be a displacement which can be measured by a gauge comparator integrated into the measurement device. The measuring step is performed simultaneously with the positioning step (82).

In the detection step (90) the detector analyses the measured parameter values received by the recording means. The detector is configured to detect a change of value of the measured parameter which occurs when the measurement device has accurately located the reference point. For example, this may be an increase of displacement because a spring loaded probe attached to the measurement device displaces into a hole or notch of the reference point as the measuring device moves over it. Once the detector detects this, the motion of the measurement device is stopped.

In the referencing step (92) the control means references the current position of the measurement device to the known position of the reference point on at least one axis. This is done by using the known position of the reference point as an input to the control means) to redefine the current position of the measurement device.

This process may be repeated in a final step (94) with a reference point in alternative known orientations to redefine measurement device position for other axes. It is also envisioned that alternative probes, capable detecting a changing parameters in more than one direction may be used, reducing the need for a reference point in additional orientations.

Claims

CLAIMS1. A method of producing a component, comprising a) Providing a movable cutting device for cutting material; a movable measurement device for measuring the cut material; recording means for recording S measured parameters of said cut material; a comparator for comparing the measured parameters with desired parameters; and a control means for controlling the position and activation of the cutting head and the position of the measurement device, wherein the method comprises the steps of; b) positioning the cutting device to cut the material to predetermined 1.0 dimensions; c) positioning the measurement device to measure one or more parameters of said cut material; d) recording the measured parameters; e) comparing the measured parameters with the desired parameters; and f) following step e), if the measured parameters deviate from the desired parameters by a defined margin, the control means position the cutting device and activate the cutting device to cut the material to meet the desired parameter within the defined margin, whereupon the cutting head is positioned to an alternative position.
2. A method according to Claim 1 wherein the cutting device is mounted on a moveable support capable of moving the cutting device in at most, 3 dimensions.
3. A method according to Claim 1 wherein the cutting device comprises a machine tool, laser cutter, water jet, knife, oscillating saw or hot wire cutter.
4. A method according to Claim 1 wherein the material comprises a composite material such as a core material or a fibre reinforced polymer matrix.
S. A method according to Claim 6 wherein the measuring device is mounted on a moveable support capable of moving the measuring device in at most, 3 dimensions..
6. A method according to Claim 1 or 2 wherein the measurement device may be mounted with the cutting device on the same moveable support.
7. A method according to Claim 1 wherein the measurement device is used simultaneously with the cutting device so that cutting and measuring can occur simultaneously.
8. A method according to Claim 1 wherein the output of the measuring device is wirelessly transmitted to the recording means.
9. A method according to Claim 1 wherein the recording means comprises computer software for transmission of output from the measurement device to a storage device.
10. A method according to Claim 1 wherein the recording means may comprise a storage device.
11. A method according to Claim 1 wherein the comparator is provided in the form of an algorithm implemented with software which converts the stored data to values that correspond to a measured physical parameter of the cut material.
12. A method according to Claim 1 wherein the measured parameters comprise dimension data, coordinate data, volume information, surface information or a point cloud.
13. A method according to Claim 1 wherein the desired parameters comprise data specified by the user which correspond to the desired shape of the component.
14. A method according to Claim 1 wherein the defined margin is a user generated input that determines the acceptable difference between the measured parameters and the desired parameters.
15. A method according to step e) of claim 1 wherein the control means uses the measured parameters to control the cutting head to cut in an alternative position.
16. A method according to claim 1 which comprises the additional step of creating a data file of measured parameters as a quality control certificate to be associated with the produced component.
17. A method according to claims ito 16 wherein step a) or b) is preceded by homing steps comprising providing: a reference point of known location, and a detector for detecting a measured a parameter(s), wherein the method comprises the steps of: d) positioning the measurement device towards a reference point; e) detecting a change in the measured parameter(s) in response to the measurement device locating the reference point; f) the control means referencing the current position of the measurement device in at least one axis to the known location of the reference point to home the control means; d) optionally repeating the above steps with a further reference point in a plane orthogonal to the original plane to obtain position for other axes.
18. The apparatus for producing a component comprising: a movable cutting device for cutting material; a movable measurement device for measuring the cut material; recording means for recording measured parameters of said cut material; comparator the measured parameters with desired parameters; a control means for controlling the position and activation of the cutting head and the position of the measurement device; and means for controlling the position and activation of the cutting head and the position of the measurement device.
19. Apparatus according to claim 18 where the cutting device is mounted on a moveable support capable of moving the cutting device in at most) 3 dimensions.
20. Apparatus according to claim 18 wherein the cutting device comprises a machine tool, laser cutter, water jet, knife, oscillating saw or hot wire cutter.
21. Apparatus according to claim 18 the material comprises a composite material such as a core material or a fibre reinforced polymer matrix.
22. Apparatus according to any of claims 18 to 21, wherein the apparatus further comprises homing means for homing the measuring device comprising providing: a reference point of known location, and a detector for detecting a measured a parameter(s), to enable positioning the measurement device towards a reference point; detecting a change in the measured parameter(s) in response to the measurement device locating the reference point; and the control means referencing the current position of the measurement device in at least one axis to the known location of the reference point to home the control means.
23. A method of homing a measurement device, comprising providing: a measurement device on a moveable support; a reference point of known location, a recording means for recording a parameter(s), a detector and; a control means for controlling the position of the measurement device, wherein the method comprises the steps of: a) positioning the measurement device towards a reference point and using the recording means to record a parameter(s); b) using the detector to detect a change in the parameter(s) as a result of the position of the measurement device locating the reference point; c) using the control means to reference the current position of the measurement device in at least one axis to the known location of the reference point; d) optionally repeating the above steps with a reference point in a plane orthogonal to the original plane to obtain position for other axes.