JP2014089175A - Laser measurement system and method in cnc machining device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method that accurately measures a side part of a machined object in a short time.SOLUTION: A system and a methd for implementing a side part measurement of a machined object 150 fixed to an XY parallel movable carriage of a CNC machining device are configured to connect a laser scanning device 110 detecting a range to a lathe of the CNC machining device parallely movable along an X-axis, a Y-axis and a Z-axis. The machined object is surrounded by a reflector 130, and the reflector is connected to the XY parallel movable carriage 120, and is preferably parallel with the X-axis and Y-axis. The laser scanning device is firstly arranged at a predetermined coordinate, directs a laser output at one of the reflectors, measures a distance from the laser scanning device to the machined object, associates the distance with a position of the laser scanning device and determines a coordinate of the machined object. Then, a scan is incremented along one of the X-axis and the Y-axis, and the other coordinate of the machined object is determined. A periphery part of the machined object is similarly scanned, and thereby the side part measurement is implemented.

Description

Related applications

  This non-provisional patent application is based on US Patent Act § 119 (e), US Provisional Application No. 61 / 668,324, filed July 5, 2012, entitled “LASER MEASUREMENT SYSTEM AND METHOD IN”. Claims "A CNC MACHINE" and US Provisional Application No. 61 / 798,836, filed March 15, 2013, the title of the invention "LASER MEASUREMENT SYSTEM AND METHOD IN A CNC MACHINE" , Both of which are incorporated herein by reference.

  The present invention relates to the field of computer-aided manufacturing systems. Specifically, the present invention relates to a system and method for measuring a portion to be machined using a laser range detection system incorporating a CNC machine.

  The CNC machine is a machine tool controlled by a numerical value of a computer. A CNC machine is used to machine a component or part called a “workpiece”. The CNC machine includes a translation table on which a workpiece is fixed. The translation table can be translated along the X axis and the Y axis. Usually, a substantially horizontal plane is defined by the X and Y axes, but translations in other directions are possible. The CNC machine further comprises at least one lathe that is independent of a translation table on which the workpiece is fixed. The lathe can be translated along the X-axis, Y-axis, and Z-axis, and can be translated in cooperation with the translation table or independently from the translation table.

  In order to be able to machine the workpiece by the CNC machine, it is necessary to perform detailed side measurements on the workpiece and input it to the CNC machine. In the prior art, this measurement is performed using a mechanical gauge. This measurement is typically performed on about 100 data points and requires about 1 minute, whereas the actual processing of the workpiece after the measurement is on the order of about 15 seconds. . If the CNC machine translation table is not equipped with a mounting system that places the workpiece at a substantially right angle to the translation table, the workpiece with respect to the coordinate system of the CNC machine is used to accurately process the workpiece. It is desirable to take into account distortion when mounting. In order to manually take into account the distortion in mounting the workpiece on the translation table, additional time is required for measurement and input of distortion data to the CNC machine.

  Current techniques for performing workpiece side measurements are slow, have a small number of data points, and are not easy to incorporate into CNC machinery.

  In order to ensure that the workpiece is processed correctly, it is necessary to accurately measure the dimensions of the workpiece. Among other things, these measured dimensions indicate that the raw workpiece meets product specifications and is machined in the correct position. Although it is desirable to measure the dimensions optically using laser light as much as possible, acoustic or other measurement methods may be used based on the principles of the present invention.

  In one embodiment, a time-of-flight (TOF) laser scanning device is connected to a lathe of a CNC machine that can translate in the XYZ directions. The workpiece is fixed to the XY translation table of the CNC machine. The workpiece is surrounded by a reflector such as a mirror or a prism fixed to the XY translation table. Alternatively, a reflector disposed on the output side of the laser scanning device may be incorporated in the laser scanning device. The CNC machine moves the lathe so that the laser scanning device moves to predetermined XYZ coordinates on the XY translation table. The light beam of the laser scanning device is directed to the XY translation table at a predetermined angle with respect to the XY plane defined by the translation table. Preferably, the rays are directed along the Z axis perpendicular to the XY plane, in which case the predetermined angle is 90 ° with respect to the XY plane. The light beam is directed to a reflector disposed along the edge of the workpiece, whereby the light beam is reflected by the reflector to the workpiece edge and further reflected at the workpiece edge, Return to the detector in the laser scanning device via the reflector. Alternatively, the light beam may be reflected by a reflector connected to the output side of the laser scanning device that directs the light beam to the edge of the workpiece. The laser scanning device measures the distance from the laser scanning device to the edge of the workpiece. This distance is associated with a predetermined XYZ coordinate of the laser scanning device, and an XY coordinate of a point on the workpiece edge is calculated. The laser scanning device is then translated along an axis parallel to the reflector and additional data points are collected. Each reflector is similarly scanned, resulting in a side measurement of the workpiece. According to the present invention, all scans can be performed in just a few seconds and more than 1000 data points are generated, resulting in both improved speed and accuracy of workpiece side measurements compared to the prior art. To do.

  The CNC machine comprises a control system having a processor and a computer readable medium, read / write memory, user interface, network interface, other I / O and auxiliary I / O. The auxiliary I / O includes analog input / output and digital input / output. The processor and / or auxiliary I / O may further comprise a PWM generation module, an interrupt controller, a digital signal processing module, a counter, and other I / Os well known in the art of embedded system design. Good. The CNC machine control software includes one or more programs that integrate the measurement system described above into the CNC machine.

  In a first aspect, a method for performing side measurements of a workpiece having a plurality of reflective ends is fixed relative to a mechanical device having a laser scanning device in which the workpiece is connected to an XYZ translation table. In position, the laser scanning device is first executed in a mechanical device provided at predetermined XYZ coordinates with respect to the workpiece. In this method, the step of arranging the laser scanning device at the next XYZ coordinate by the XYZ translation table (when this is performed first, the “next” XYZ coordinate is the initial XYZ coordinate), the laser. A step of reading a distance from the laser scanning device to the reflection point on the first reflection end of the plurality of reflection ends of the workpiece by using the light beam emitted from the laser scanning device by the scanning device; And determining the XY coordinates of the workpiece and repeating these steps until all the side measurements of the workpiece are performed. The step of performing the side measurement preferably includes a step of determining the XY coordinates of the reflection point at a plurality of points at each of the plurality of reflection ends. In one embodiment, all side measurements are taken when a discrete distance measurement is made along the entire periphery of the workpiece (eg, along each edge). In a preferred embodiment, the workpiece is substantially rectangular, the workpiece is substantially aligned with the XY plane of the XYZ translation table, and the change of the position of the laser scanning device is on one of the X axis and the Y axis. Along with incrementing the position of the laser scanning device. The method preferably further comprises the step of storing XY coordinates. If no reflection corresponding to the light beam emitted by the laser scanning device is received, the invalid coordinates are stored. In a preferred embodiment, the method further comprises determining a workpiece identifier. The identifier is preferably scanned using a laser scanning device. From the identifier, a predetermined set of optimal coordinates associated with the identifier can be read. The method preferably further comprises the step of comparing the stored coordinates with a predetermined set of optimal coordinates. In such an embodiment, the mechanical device further comprises a notification system, wherein the method includes the fact that the stored coordinates substantially match and did not substantially match the predetermined set of optimal coordinates. The method further includes issuing a notification indicating one of the following.

  In a second aspect, a system for performing side measurement of a workpiece having a plurality of reflective ends includes an XYZ translation table, a laser scanning device connected to the XYZ translation table, and a workpiece. A platen that is received at a fixed position with respect to the XYZ translation table and a controller. The controller arranges the XYZ parallel movement table at a predetermined next XYZ coordinate with respect to the workpiece, controls the laser scanning device, and uses the light beam emitted by the laser scanning device, from the laser scanning device. Read the distance to the reflection point on the first reflection end of the plurality of reflection ends of the workpiece, determine the XY coordinates of the reflection point, and execute all side measurements of the workpiece Repeat these steps. In some embodiments, the platen includes a plurality of reflectors that reflect the light beam to a point on each of the plurality of reflective ends of the workpiece. The workpiece is preferably substantially rectangular, and the reflector is arranged parallel to the reflection end of the workpiece. In a preferred embodiment, the laser scanning device includes a reflector that reflects the light beam to a point above the reflective end of the workpiece. In such an embodiment, the XYZ translation stage rotates the laser scanning device in the Z axis perpendicular to the top surface of the platen. In a preferred embodiment, the controller changes the position of the XYZ translation platform to a second predetermined XYZ coordinate that lies on a line that passes through the first predetermined XYZ coordinate and is parallel to one of the plurality of reflection ends. In some embodiments, the controller changes the position of the XYZ translation platform to a second predetermined XYZ coordinate that is on a line defined by one axis of the plurality of reflectors.

  In a third aspect, a non-transitory computer readable medium programmed with instructions executable by a processor is programmed to carry instructions that, when executed, implement any of the methods described above.

  The embodiments described by the detailed information in the following drawings illustrate features of the present invention by way of example. Similar reference numbers refer to similar or identical elements.

FIG. 1 illustrates a system for laser measurement according to some embodiments. 1 is a partial cross-sectional side view of a system that performs side measurements of a workpiece according to some embodiments. FIG. 1 is a partial cross-sectional side view of a system that performs side measurements of a workpiece according to some embodiments. FIG. FIG. 6 illustrates side measurements of a workpiece having rounded corners according to a system embodiment. FIG. 6 illustrates a side measurement of a workpiece having an offset according to some embodiments. FIG. 6 is a diagram illustrating a measurement grid that performs side measurements of a workpiece according to some embodiments. FIG. 4B is a side sectional view of the measurement grid of FIG. 4A. 6 is a flow chart illustrating steps of a method for side measurement of a workpiece according to some embodiments. 6 is a flow chart illustrating steps of a method for identifying a workpiece that performs side measurements according to some embodiments.

  FIG. 1 illustrates a system 100 for measuring a side of a workpiece according to some embodiments. The system 100 includes a system support 105, a laser scanning device 110 having a detector 115 (shown in FIGS. 2A and 2B), an XY translation table 120, a plurality of holders 140 and accompanying devices (FIGS. 2A and 2B). A plurality of reflectors 130 held by fasteners 145 and workpiece 150 to be measured (shown in FIG. 2B). The workpiece 150 has a plurality of reflection ends 135. The workpiece 150 is mounted on the XY translation table 120, whereby the workpiece 150 can move in the XY direction on a plane defined on the upper surface of the XY translation table 120. The laser scanning device 110 is directed so that a laser beam 160 (shown in FIGS. 2A and 2B) emitted from the laser scanning device 110 is substantially perpendicular to the plane of the workpiece 150 and the XY translation table 120. . The laser beam 160 is directed to one reflector 130 of the plurality of reflectors 130. The plurality of reflectors 130 are arranged around the vicinity of the workpiece 150, whereby the laser light 160 is reflected by the reflector 130 toward the reflection end 135 of the workpiece 150 (FIG. 2A). And as indicated by reference numeral 165 in 2B), the light is reflected by the reflection end 135 and returned to the reflector 130, and further reflected by the reflector 130 and returned to the detector 115. The laser scanning device 110 measures the distance from the laser scanning device 110 to the workpiece 150. Using this distance and the XYZ coordinates of the laser scanning device, the XY coordinates of the reflection point of the laser beam 160 on the reflection end 135 are determined. These coordinates are stored as data. The laser scanning device 110 translates to one reflector 130 of the plurality of reflectors 130 and then acquires and stores other measurement values. It will be apparent to those skilled in the art that modifications can be made within the scope of the present invention. For example, the scanner system 110 may be mounted on an XYZ translation table and the workpiece 150 may be fixed at a certain position.

  FIG. 2A is a cross-sectional side view of system 100 that performs side measurements on workpiece 150. The CNC machine (not shown) includes an XY translation table 120, a laser scanning device 110 having a detector 115, and a reflector 130 held on the XY translation table 120 by a holding unit 140 having a fastener 145. Is provided. The laser scanning device 110 is arranged at a predetermined Z coordinate with respect to the XY translation table 120 by a CNC machine. During the side measurement of the workpiece 150, the predetermined Z coordinate remains constant. The laser scanning device 110 emits a laser beam 160 reflected by the workpiece 150 by the reflector 130. The laser beam 160 is reflected by the reflection end 135 of the workpiece 150 to become reflected light 165, and subsequently reflected by the reflector 130 to the detector 115. The laser scanning device 110 calculates the distance from the laser scanning device 110 to the detector 115 via the workpiece 150 by calculating the “travel time” of the laser light 160 and the reflected light 165 reflected as described above. . By dividing the reciprocal path of the laser beams 160 and 165 by 2, a one-way laser beam travel distance from the laser scanning device 110 to the reflection end 135 of the workpiece 150 can be obtained. By subtracting the unidirectional travel distance of the laser light 160 in the Z direction from the overall travel distance of the laser light 160 in one direction, the distance from the reflection point on the reflector 130 to the workpiece 150 is obtained. The XY coordinate of the reflection point of the reflected light 165 on the workpiece 150 is obtained by adding or subtracting the distance from the reflection point of the reflector 130 to the coordinate of the reflection point by the reflector 130 from the coordinate of the reflection point by the reflector 130. be able to. (A detailed explanatory diagram of the coordinate calculation is shown as FIG. 4.) The laser scanning device 110 translates incrementally along the axis 180 (shown in FIG. 4) of the reflector 130, and the workpiece is processed at each increment. 150 additional coordinates are determined. By scanning each reflective end 135 of the workpiece 150 in the same manner, all sets of coordinates of the workpiece 150 are generated. The laser beam 160 emitted from the laser scanning device 110 is shown as being offset from the reflected beam 165 for explanation only. In fact, it will be apparent to those skilled in the art that the laser beams 160, 165 are in the same position. Although the present invention is described herein with reference to a laser scanning device, it will be apparent to those skilled in the art that a sonic scanner may be used. However, it is preferable to use a laser scanning device because of its high accuracy.

  FIG. 2B illustrates a cross-sectional side view of a system 100 that performs side measurements of a workpiece on a CNC machine in accordance with some embodiments. In this embodiment, a single reflector 130 is mechanically connected to the laser scanning device 110 via a reflector arm 170. The reflector 130 is disposed at a predetermined fixed distance from the laser scanning device 110. The laser scanning device 110 is mounted on an XY translation table (not shown), and a fixed table 120 'is provided instead of the XY translation table 120 of FIG. 2A. The reflective end 135 of the workpiece 150 is scanned along a line parallel to the reflective end 135, similar to the scan along the center line of the reflector 130 shown in FIGS. 1 and 2A. In this specific example, the laser scanning device rotates 90 degrees clockwise around the Z axis, and the next reflection end 135 of the workpiece 150 is similarly scanned. Each of the remaining two reflection ends 135 of the rectangular workpiece 150 is similarly scanned, and the coordinates of the workpiece 150 are obtained in the same manner as in FIGS. 1 and 2A.

  FIG. 3A shows a side measurement of a work piece 150 having a rounded corner with a radius R. FIG. 3A is a partial plan view of the side measurement system. The holding part 140 and the fastener 145 are omitted for the sake of clarity. The side measurement system 100 shown here includes a plurality of reflectors 130 fixed around the workpiece 150. In this embodiment of the side measurement system 100, the reflector 130 reflects the laser light 160 toward the reflective end 135 of the workpiece 150, and the reflective end 135 then reflects the laser light 160 in the return direction. Thus, the reflected light 165 is generated, and the reflected light 165 is detected by the detector 115 provided in the laser scanning device 110. The laser beams 160-1 to 160-5 are emitted downward from the laser scanning device 110. The point where the light beam, for example, the laser beam 160-1 hits the reflector 130 is indicated by a white circle at the start end of the arrow indicating the light beam direction. If the reflective end 135 of the workpiece 150 is rounded or not perpendicular, the reflected light 165 is not detected by the detector 115. Here, a plurality of laser beams 160-1 to 160-5 and reflected light 165-1 to 165-5 are shown. The first and second reflected lights 165-1 and 165-2 are reflected in parallel to the incident laser lights 160-1 and 160-2, respectively. The reflected lights 165-1 and 165-2 are detected and measured by the detector 115. The third and fourth laser beams 160-3 and 160-4 hit the reflection end 135 at the bent portion of the reflection end 135. Accordingly, the reflected light 165-3 and 165-4 are not detected by the detector 115. Since the laser beam 160-5 strikes the workpiece 150 at the reflection end 135 of the workpiece 150 orthogonal to the laser beam 160-5, the laser beam 160-5 becomes the reflected beam 165-5 and is a detector. 115 is reflected back.

  FIG. 3B illustrates a side measurement of a workpiece 150 having an offset, according to some embodiments. This figure is a partial plan view of the side measurement system 100. The holding part 140 and the fastener 145 are omitted for the sake of clarity. The side measurement system 100 shown here includes a plurality of reflectors 130 fixed around the workpiece 150. Similar to the embodiment of FIG. 3A, the laser light 160 is reflected from the reflector 130 toward the reflective end 135 of the workpiece 150. The reflection end 135 reflects the laser light 160 as reflected light 165 and returns it to the reflector 130, and the reflected light 165 is detected by the detector 115 provided in the laser scanning device 110. The reflected light 165 is not detected by the detector 115 if the work piece 150 has an offset in the reflective end 135, or has other non-right angle ends. Here, a plurality of laser beams 160-10 to 160-15 and reflected light 165-1 to 165-15 are shown. The first reflected light 165-10 is reflected parallel to the incident laser light 160-10. The reflected light 165-10 is detected and measured by the detector 115. The second laser light 160-11 hits the reflection end 135 at the offset portion of the end of the workpiece 150. Therefore, the reflected light 165-11 is not detected by the detector 115. Since the laser beams 160-12 to 160-15 strike the part of the reflection end 135 orthogonal to the laser beams 160-12 to 160-15, the laser beams 160-12 to 160-15 are reflected beams 165-12 to 165- 15 is reflected back to the detector 115.

FIG. 4A shows a measurement grid for performing side measurements on the workpiece 150. Element 180 represents the centerline of the scan path of the reflective end 135 of the workpiece 150. In an embodiment where multiple reflectors 130 are fixed to the XY translation stage 120, the element 180 represents the axis of the reflector 130 and the scan path of the laser scanning device 110. In embodiments where the laser scanning device 100 comprises a reflector 130, the element 180 represents the scanning path of the laser scanning device 110. In the embodiment in which the element 180 is superimposed on an arbitrary XY coordinate space on which the XY translation table 120 moves the workpiece 150 or the workpiece 150 is fixed and the laser scanning device 110 is translated, the laser scanning device is used. 110 is superimposed on an arbitrary XY coordinate space that is translated. 4B is a cross-sectional side view of the grid at line AA of FIG. 4A used to further illustrate the elements of the system 100. Element 180 intersects at four arbitrarily named points (X ₀ , Y ₀ ), (X ₀ , Y ₁ ), (X ₁ , Y ₁ ) and (X ₁ , Y ₀ ). A process for executing the scanning will be described later with reference to FIG. 4A and 4B show the calculation principle for determining the coordinates of the workpiece 150. FIG. As shown in FIG. 4B, the laser scanning device 110 is positioned at a height d ₁ above an arbitrary scanning point (X ₀ , Y _i ). Measurements are made by directing the laser beam 160 to a point (X ₀ , Y _i ) on the reflector 130. The laser scanning device 110 measures the reciprocal path (shown as 160/165) of the emitted laser light 160 and its reflected light 165, and divides this by 2 to calculate one distance, from which d ₁ The value of d _i is calculated by subtracting. The coordinates of the workpiece at this measurement point are (X ₀ + d _i , Y _i ). Laser scanning device 110, while the X-coordinate and the X _0, is incremented (perpendicular to the paper surface of the figure) in the Y direction. For each increment, the distance to the reflection end 135 of the workpiece 150 is measured, and the coordinates of the workpiece 150 are determined. Then, the laser scanning device performs further measurement at the second position (X ₁ , Y _j ) as indicated by reference numeral 110 ′ with a dash. A reciprocal path (shown as 160 ′ / 165 ′) of the emitted laser beam 160 ′ and its reflected light 165 ′ is measured, and this is divided by 2 to calculate one distance, and d ₁ is subtracted therefrom. Thus, the value of _dj is calculated. As a result, the coordinates of the workpiece 150 at the measurement point are (X ₁ -d _j , Y _i ). Also shown in FIG. 4B is a partial ID area 190 that identifies the type of portion being measured. The part ID is assigned to the CNC machine, and the CNC machine can read the CNC information of a particular type of part having that part ID. FIG. 6 shows the steps of a method 600 for scanning the partial ID region 190.

FIG. 5 illustrates the steps of a method 500 for workpiece side measurements according to some embodiments. The measurement method starts at step 505, where the type of the part to be measured is determined by the part ID. The partial ID may be entered manually into the side measurement system or may be determined by scanning the partial ID area 190 with the laser scanning device 110. The side measurement scan is started at the first position X ₀ , Y ₀ of the laser scanning device. In step 510, as described above with reference to FIG. 4B, the position of the laser scanning device is incremented in the Y direction to perform measurement. In step 515, if the Y coordinate of the laser scanning device becomes Y _1, by stopping the Y-direction of the measurement scan of the reflecting end X-coordinate is X _0, the measurement method proceeds to step 520. Otherwise, the measurement method returns to step 510. In step 520, the position of the laser scanning device whose initial values are X ₀ and Y ₁ is incremented in the X direction, and measurement is performed. In step 525, if the X coordinate of the laser scanning apparatus becomes X _1, Y coordinate measurement stops scanning of the reflection edge is Y _1, the measurement method proceeds to step 530. Otherwise, the measurement method returns to step 520. In step 530, the position of the laser scanning device whose initial values are X ₁ and Y ₁ is decremented in the Y direction, and measurement is performed. In step 535, if the Y coordinate of the laser scanning device position becomes Y _0, X coordinate measurement stops scanning of the reflection edge is X _1, the measurement method proceeds to step 540. Otherwise, the measurement method returns to step 530. In step 540, the position of the laser scanning device whose initial values are X ₁ and Y ₀ is decremented in the X direction, and measurement is performed. In step 545, if the X coordinate of the laser scanning apparatus becomes X _0, Y coordinate measurement stops scanning of the reflection edge is Y _0, the measurement method 500 ends. Otherwise, the measurement method returns to step 540.

  As an example, the laser scan moves in a predetermined pattern that traverses the entire periphery of the workpiece with a discontinuous offset. In other embodiments, the laser scan may be traversed to scan a sufficient number of points to make an accurate measurement of the workpiece, rather than the entire periphery of the workpiece.

FIG. 6 illustrates the steps of a method 600 for identifying a workpiece to perform side measurements according to some embodiments. As shown in FIG. 4B, a partial ID region 190 is provided on the reflection end of the workpiece 150. In step 605, the laser scanning device is first placed at X ₀ , Y ₀ . The partial ID area ends with X ₁ , Y ₀ . In step 610, measurement is performed by incrementing the X coordinate of the laser scanning device. As described above, the measurement value is converted into coordinates. In step 615, if the X coordinate of the laser scanning apparatus becomes _{X 1,} the method proceeds to step 620. Otherwise, the method returns to step 610. In step 620, the coordinates of the partial ID are decoded. A method for decoding the partial ID from the coordinates will be described later.

System Integration The side measurement process described here is a pre-processing step in machining a workpiece. Thus, the side measurement system can be integrated into existing CNC machinery. In such integration, the laser scanning device is connected via an interface to a processor in the CNC machine, whereby the workpiece coordinates generated by the laser scanning device are sent as data to the CNC machine. The CNC machine is already programmed to machine the workpiece, and therefore the CNC machine contains data describing the workpiece before and during machining. The coordinates generated by the laser scanning device can be compared with design data for the workpiece stored in the CNC machine. In order to facilitate comparison and the like, the CNC data can refer to a partial ID. The workpiece to be machined and its side measurements can also be referenced by the part ID.

Decoding Part ID The part ID described here is an identifier for a particular class of workpiece 150. The part ID associates a workpiece 150 of a particular type or shape with the CNC command, which processes all workpieces 150 of that particular type or shape. The partial ID may be manually entered into the CNC machine before performing the side measurement process. Alternatively, the part ID may be scanned from a sticker or machining on the workpiece 150. The laser scanning device 110 detects the presence or absence of reflection, and when there is reflection, calculates the distance from the laser system to the reflection point on the workpiece 150. For this reason, the laser scanning device can detect both the depth and width of machining on the reflective end 135 of the workpiece 150. Accordingly, the partial ID can be comprised of machining having various depths, widths and / or reflectivities within the partial ID region 190 on the workpiece 150. The scanned depth, width and / or reflectivity pattern is passed to the CNC machine and converted to a partial ID based on the pattern stored in the CNC machine.

Non-Reflective Portion of Workpiece As described with reference to FIGS. 3A and 3B, the work piece 150 does not necessarily include only the orthogonal reflection ends. If there is no distortion or offset, the curved edge or offset that becomes the reflection end is due to the fact that the detector 115 did not receive the reflected light 165 corresponding to the laser light 160 emitted by the laser scanning device 110 during the measurement. It can be detected. Non-reflective areas are stored as invalid coordinates. Invalid coordinates are, for example, negative coordinates, coordinates that are apparently invalid, or coordinates having other logically invalid values. The coordinates of these non-reflective regions can then be compared with a set of optimal coordinates in the CNC machine to determine whether the workpiece 150 matches the optimal coordinates. If the deviation of the measured coordinates from the optimal coordinates is greater than the threshold, it can be logically assumed that the workpiece 150 has the wrong part ID and the machining of the CNC machine is started. Before, appropriate notifications can be made to the operator of the side measurement / CNC system. Such a comparison can specify a manufacturing defect of the workpiece 150 and can specify that an inappropriate part ID is given to the workpiece 150. In either case, the scrap produced can be reduced by comparing the side measurement coordinates with the optimal coordinates of the CNC machine before machining the workpiece.

Improving scanning efficiency As described above, the side measurement system can be incorporated into a CNC machine. The CNC machine includes machining instructions for the workpiece 150. The machining instruction can refer to the part ID of the workpiece. By incorporating the laser measurement process into the CNC machine, the optimal coordinates for the workpiece 150 are pre-processed to determine where the non-reflective area of each reflective end 135 of the workpiece 150 is located. can do. And the side measurement process described here can be modified to skip these non-reflective areas, thereby eliminating wasted time by scanning the non-reflective part of the reflective end. As a result, the speed of the side measurement can be increased.

  In actual operation, the workpiece is placed on the platen and fixed to the platen. The workpiece typically has a substantially rectangular shape with a reflective end. The laser scanning device measures the coordinates of the reflection end for the entire peripheral portion of the workpiece, and stores the coordinates. The increment between each laser measurement for the reflective edge can be varied to take into account the balance between the speed of scanning and the number of data points collected. The side measurement coordinates are stored and applied to the CNC machine prior to machining by the CNC machine.

  Specific embodiments have been described in order to illustrate the features of the invention. It will be apparent to those skilled in the art that the embodiments can be changed without departing from the spirit and scope of the invention as defined by the appended claims.

Claims (17)

A method for performing side measurement of a workpiece having a plurality of reflective ends, wherein the workpiece is in a fixed position relative to a mechanical device having a laser scanning device connected to an XYZ translation table. In the method of first providing the laser scanning device at predetermined XYZ coordinates with respect to the workpiece,
a. Placing the laser scanning device at the next XYZ coordinates by the XYZ translation table;
b. The step of reading the distance from the laser scanning device to the reflection point on the first reflection end of the plurality of reflection ends of the workpiece using the light beam emitted from the laser scanning device by the laser scanning device When,
c. Determining the XY coordinates of the reflection point;
d. Repeating the steps a, b and c until all side measurements of the workpiece are performed.   The method of claim 1, wherein performing the side measurement includes determining XY coordinates of the reflection point at a plurality of points at each of the plurality of reflection ends.   The workpiece is substantially rectangular, the workpiece is substantially aligned with the XY plane of the XYZ translation table, and the change of the position of the laser scanning device is along one of the X axis and the Y axis. The method of claim 2 including incrementing the position of the laser scanning device.   The method of claim 2 further comprising the step of storing the XY coordinates.   5. The method of claim 4, further comprising the step of storing invalid coordinates if no reflection corresponding to the light emitted by the laser scanning device is received.   The method of claim 5, further comprising the step of determining an identifier of the workpiece.   The method of claim 6, wherein the step of determining the identifier of the workpiece includes scanning the identifier using the laser scanning device.   The method of claim 6, further comprising reading a predetermined set of optimal coordinates associated with the identifier.   9. The method of claim 8, further comprising comparing the stored coordinates with the predetermined set of optimal coordinates.   The mechanical apparatus further includes a notification system, wherein the method is configured to determine whether the stored coordinates substantially match or do not substantially match the predetermined set of the optimal coordinates. The method of claim 9, further comprising issuing a notification to indicate. In a system for performing side measurements of a workpiece having multiple reflective edges,
a. An XYZ translation table;
b. A laser scanning device connected to the XYZ translation table;
c. A platen for receiving the workpiece at a fixed position with respect to the XYZ translation table;
d. With a controller,
The controller
1. Placing the XYZ translation table at a predetermined next XYZ coordinate relative to the workpiece;
2. The laser scanning device is controlled to use the light beam emitted from the laser scanning device to the reflection point on the first reflection end of the plurality of reflection ends of the workpiece from the laser scanning device. Read the distance,
3. Determine the XY coordinates of the reflection point,
4). A system that repeats steps 1, 2 and 3 until all side measurements of the workpiece are performed.   The system of claim 11, wherein the platen includes a plurality of reflectors that reflect the light beam to points at each of a plurality of reflective ends of the workpiece.   The system of claim 11, wherein the laser scanning device includes a reflector that reflects the light beam at a point on a reflective end of the workpiece.   The system according to claim 13, wherein the XYZ translation stage rotates the laser scanning device in a Z axis perpendicular to an upper surface of the platen.   The controller changes the position of the XYZ translation base to a second predetermined XYZ coordinate passing through the first predetermined XYZ coordinate and on a line parallel to one of the plurality of reflection ends. The described system.   13. The system of claim 12, wherein the controller changes the position of the XYZ translation platform to a second predetermined XYZ coordinate having a line defined by one axis of the plurality of reflectors. A method for performing side measurements on a workpiece having a plurality of reflective edges in a non-transitory computer readable medium programmed with instructions executable by a processor, wherein the workpiece is an XYZ translation platform A computer-readable medium for executing a method in which the laser scanning device is initially provided at a predetermined XYZ coordinate with respect to the workpiece at a fixed position relative to a mechanical device having a laser scanning device connected to In
The above method
a. Placing the laser scanning device at the next XYZ coordinates by the XYZ translation table;
b. The step of reading the distance from the laser scanning device to the reflection point on the first reflection end of the plurality of reflection ends of the workpiece using the light beam emitted from the laser scanning device by the laser scanning device When,
c. Determining the XY coordinates of the reflection point;
d. Repeating the steps a, b and c until all side measurements of the workpiece are performed.

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