JPS6129710A - Measuring method - Google Patents

Abstract

PURPOSE:To measure the shape and position of a work precisely in a short time by deriving positions of respective points on the surfaces of a work continuously. CONSTITUTION:The 2nd moving body 7 rotates by a specific angle and moves to the right and left together with the 1st moving body 6. Image pickup means 9a and 9b are movable to the right and left and a light source 10 is supported rotatably in the 1st moving body 6. A point P on a line L parallel to the X axis of the work 8 within the overlap visual field of the image pickup means 9a and 9b is irradiated to derive image pickup surfaces and an actual position by an image processing means. Then, the light source 10 is rotated to irradiate a next point, and the image pickup range is moved in the X-axial direction to irradiate respective points on the line L. Further, the 1st and the 2nd moving bodies 6 and 7 are moved in the X-axial direction to derive the positions of the respective points on the line L. Then, said operation is repeated every time the 2nd guide body 3 is moved in the Z-axial direction to derive the shape and position continuously. Further, the spot diameter is reduced and the image pickup means 9a and 9b are increased in magnification to measure even a fine shape and a surface form.

Description

[Detailed description of the invention]

[Industrial Field of Application] The present invention relates to a measuring method for determining the position of each point on the surface of an object to be measured and measuring the shape of the object. [Prior Art] Conventionally, as a method of deriving the position of each point on the surface of a measured object and measuring the shape of the measured object, contact is used to measure the shape of the measured object by bringing a sensing probe into contact with the measured object. stereo photography, which measures the shape of the object by capturing images of the same object simultaneously with two cameras and finding common points between both images; The moiré topography method is based on which the shape of the object to be measured is measured, and the shape of the object is determined by irradiating the object with a vertical slit light, capturing an image of the irradiated area with a television camera, and finding the characteristic points in the image. There are non-contact methods such as the optical cutting method that measure the amount of light, and these methods are widely applied as object recognition technology for industrial robots or for various inspection devices. However, the contact method described above has the disadvantage that measurement takes a long time, and even in the case of a non-contact method, the position of the object, that is, the position in any coordinate system, can only be determined by recognizing the shape of the object. Since the coordinates are not directly measured, in order to determine the position of the object to be measured, the target point is determined from the obtained image, and then the position, or coordinates, of the determined point is calculated. The measurement equipment that implements these methods has a very low resolution valve, so it is difficult to use when the object to be measured is small or there are small irregularities on the surface of the object to be measured. The method has the disadvantage that it cannot accurately recognize the shape of the object to be measured or the state of surface irregularities, and is therefore unreliable, making it insufficient for measuring the shape, etc. of the object to be measured. [Object of the invention] This invention has been made with the above points in mind,
The purpose is to enable accurate measurement of the shape and position of an object to be measured in a short time. [Structure of the Invention] The present invention provides a pair of imaging means for imaging an object to be measured, which are movable in the front and back directions, and whose respective imaging ranges are movable in the left and right directions, and a light source that emits slit light. , can move freely in the front and back directions. and the irradiation point of the slit light is provided to be movable in the left-right direction, and the light source sequentially irradiates the slit light at a plurality of locations on a line in the left-right direction on the surface of the object to be measured within the overlapping field of view of the re-imaging means; With the slit light from the light source fixed at a certain irradiation point, the imaging range of the re-imaging means is moved in the left-right direction within a range that includes the certain irradiation point, and the image within the overlapping field of view of the re-imaging means after the movement is The slit light is irradiated to a plurality of locations on the line on the surface of the object to be measured, and the overlapping field of view is sequentially moved and the irradiation point of the slit light is moved every time the re-imaging means and the light source are moved in the front and back direction. Repeatedly, the image processing means processes the image taken by the re-imaging means of each irradiation point for each of the slit lights on the surface of the object to be measured to derive the position of each irradiation point, and This measurement method is characterized by measuring the shape of the body. [Effects of the Invention] Therefore, according to the measurement method of the present invention, the imaging ranges of both imaging means are sequentially moved in the left-right direction, and the surface of the object to be measured is measured in the left-right direction within the overlapping field of view of the re-imaging means after each movement. The slit light is irradiated to multiple locations on the line, and the sequential movement of the overlapping field of view and the movement of the slit light irradiation point are repeated each time the re-imaging means and the light source are moved in the front and back direction, and the image processing means By processing the image of each irradiation point on the surface and deriving the position of each irradiation point to measure the shape of the object to be measured, even if the object to be measured is large,
The position of each point on the surface of the object to be measured can be continuously derived, and the shape and position of the object to be measured can be derived at the same time.
By simply expanding the imaging range of the re-imaging means, it is possible to measure the minute shape and surface condition of the object to be measured, making it possible to measure the shape and surface condition of the object in a short time. , very practical. Furthermore, when moving the overlapping field of view of the re-imaging means, the slit light is fixed at a certain irradiation point and the imaging range of the re-imaging means is moved in the left-right direction within a range that includes the certain irradiation point, so the overlapping field of view is Even when moving, the irradiation point can always be set on the same line in the left-right direction, and the position of each point on the surface of the object to be measured can be accurately derived to accurately measure the shape of the object to be measured. [Example] Next, the present invention will be described in detail with reference to drawings showing examples thereof. First, FIGS. 1 to 4 showing the first embodiment will be explained. In those drawings, (I) is a first guide body in the front and rear direction provided at a predetermined height on the pedestal, and a second guide (described later) attached to the rear end of (21 is the first guide body + 1) The first motor for moving the body (3) has both ends connected to the first motor (2).
), a second guide body which is elongated in the left-right direction and whose left lower end is screwed onto the first feed screw which is locked to the rotating shaft and the bearing, and which is movable in the front-back direction; +51 is a telescopic bellows-shaped covering body provided to cover the front and rear parts of the second guide body (3) of the 1-feed screw, respectively. ) A second motor and a bearing for moving the first moving body, which will be described later, are attached to the left and right ends of the upper part. An actuating body (61') is integrally formed at the end, and both ends are connected to the second motor (6), and the actuating body (61' is screwed to the second feed screw locked to the bearing (51') to move the first movement. The body (6) is movable in the left and right direction in front of the second guide body (3). (7) is rotatably provided on the front side of the first movable body (6), and is moved by the third motor. The first moving body (6) rotates by a predetermined angle.
(8) is a second moving body in the form of a casing with an open bottom that moves in the left-right direction along with the object to be measured ((8) placed on the pedestal;
(hereinafter referred to as works), (9a), and (9b) are fixed to the left end and right end of the second moving body (7), and their respective imaging ranges are movable in the left and right direction. The first and second imaging means (lO), which is composed of a CCD type linear image sensor or the like that images the workpiece (81), is a slit light whose upper end is rotatably supported inside the first moving body (6). The light source consists of a laser that irradiates a spot light and a xenon lamp with a circular slit, and as shown in FIG. The first connecting plate (
The upper end of the light source (lO) is rotatably connected via a second connecting plate (12) whose one end is connected to the other end of the first connecting plate (12), The light source (l
The lower end of O) is designed to rotate. In addition, (14) is arranged at the right side of the first guide body +11, the upper end part and the lower end part of the front side of the second guide body (3), respectively, and the second guide body (3) and the first movable body (6 ) is a linear bearing that reduces friction during movement and facilitates movement. Although not shown, both imaging means (9a) and (9b
) and the spot light irradiation point are sequentially moved by the imaging means (9a), (9b) and the light source (1ω
The work piece (
8) is provided with image processing means for processing the images taken by the two imaging means (9a) and (9b) of each irradiation point for each of the slit lights on the surface and deriving the position of each irradiation point. ing. Now, as shown in Figure 1, the x, y, and z axes of the XYZ coordinate system are taken in the left and right, up and down directions, and the workpiece is
), that is, the coordinates in the XYZ coordinate system, to measure the shape of the workpiece (8), the second guide body (3) is stopped at a predetermined position, and the second moving body ( 7) at a predetermined angle position to fix the overlapping fields of view of both imaging means (9a) and (9b), and to detect the surface of the workpiece (8) within the overlapping field of view of both imaging means (9a) and (9b). A spot light from a light source (lO) is irradiated to a certain irradiation point P on a line parallel to the X-axis, and both imaging means (9a) and (9b
) to simultaneously image the vicinity of the spot light irradiation point P, and image processing means to simultaneously image the vicinity of the spot light irradiation point P, and image processing means to simultaneously image the vicinity of the spot light irradiation point P.
, (9b), the position of the brightest point among the images near the irradiation point P, that is, both imaging means (9a) of the irradiation point P.
, (9b) on the imaging plane, converting the position of the irradiation point P on both the imaging planes into the position of a point on the reference plane including an arbitrary reference line parallel to the X-axis, and The position of the actual irradiation point P on the workpiece (8), that is, the X, Y coordinate components and the second guide, is the intersection of two straight lines connecting each pixel on the imaging plane and each pixel on the reference plane. A coordinate consisting of a Z coordinate component determined by the position of the body (3) is derived. Next, the fourth motor (11) is driven to rotate the light source (10) within a plane that includes the line, and both imaging means (9a), (
Irradiating the spot light to the next irradiation point after the irradiation point P on the line in the overlapping field of view in 9b), and deriving the position of the irradiation point in the method in the same manner as deriving the position of the irradiation point P, and , the position of each irradiation point on the line within the overlapping field of view is derived, and when the irradiation point of the spotlight reaches the end point of the line within the overlapping field of view, the next irradiation point is located on the overlapping field of view. Therefore, with the spot light fixed at the irradiation point P' shown in FIG.
As shown in the figure, by rotating the second moving body (7) by a predetermined angle, the imaging range of both imaging means (9a) and (9b) is adjusted to the irradiation point P.
' is moved in the X-axis direction, and after the movement, the surface imaging means (9a). Spot light is irradiated onto each irradiation point on the line on the surface of the workpiece (8) within the overlapping field of view (9b). Then, similarly to deriving the position of the irradiation point P described above, the position of each irradiation point on the line on the surface of the workpiece (8) within the overlapping field of view after movement, that is, the coordinate in the XYZ coordinate system, is derived, and further In addition to the rotation of the second moving body (7), the second moving body (7) is moved along the second guide body (3) together with @1 moving body (6), and these After repeating the operation and deriving the position of each irradiation point on the line on the surface of the workpiece (8), the second moving body (7) is rotated in the opposite direction and moved in the negative direction of the X axis. The imaging range of the surface imaging means (9a) and (9b) is returned to the measurement starting position, and then the second guide body (3) is moved by a predetermined amount in the positive direction of the Z-axis by the operation of the first motor (2). and repeat the above operation again, and move the second guide body (3)
The above operation is repeated each time the workpiece (8) is moved in the positive direction of the Z-axis by the predetermined amount, and the image processing means
The position of each irradiation point above, that is, the X, Y coordinate components and the second
Each coordinate consisting of a Z-axis component determined by the amount of movement of the guide body +31 is derived, and based on the derived coordinates of each irradiation point, the shape and position of the workpiece (8) are measured at the same time. Therefore, according to the embodiment, the workpiece (8) is produced, the spot diameter of the spot light is reduced, and the magnification of the surface imaging means (9a), (9b) is increased. ) by simply expanding the imaging range of
It is also possible to measure the minute shape and surface condition of the workpiece (8), making it possible to measure the shape and surface condition of the workpiece (8) in a short time, and it can also be applied to surface inspection equipment. It is very practical. Furthermore, when moving the overlapping fields of view of the surface imaging means (9a) and (9b), the imaging range of the surface imaging means (9a) and (9b) is changed to the certain irradiation point with the spot light fixed at a certain irradiation point. Since it moves in the left-right direction in a range that includes The shape etc. of the workpiece (8) can be measured with high accuracy. In addition, since the shape of the workpiece (8) is shaped without contact, even if the workpiece (8) is a flexible and easily deformable material such as rubber,
Shape etc. can be easily measured. Sara

[Since spot light is used, the energy density is low and weak light is sufficient, and the workpiece (8) will not be distorted by the heat of the illumination when the illumination is used. Next, FIGS. 5 and 6 showing other embodiments will be described. First, in FIG. 5, the same symbols as in FIGS. 1 to 3 indicate the same things, and the differences from FIGS. 1 to 3 are as follows.
A third guide body (15), which is elongated in the left-right direction and whose left lower end portion is screwed to the first feed screw, is provided, and a third guide body (16) is provided.
At the right end of the front surface, there is a surface imaging means (9a). (9b) is fixedly stored in the housing (I6), and the upper end of the housing (I6) is rotatably attached, and the light source (16) is installed inside the housing (16).
10) is housed so as to be rotatable regardless of the rotation of the housing (16), and the fifth motor (1η is attached to the stepping motor approximately at the center of the third guide body (15), and the fifth motor 07) is rotated. One end of the rotating body (18) is attached to the shaft,
The other end of the operating rod 09, one end of which is fitted into the through hole at the other end of the rotating body (18), is rotatably connected to the lower end of the left side of the casing (I6I) to operate the fifth motor (I7). The lower end of the casing (16) is rotated by the rotation of the rotating body θ8) to move the imaging range of the surface imaging means (9a) and (9b). In addition, as shown in Fig. 6, there is a sixth motor equipped with a speed reduction mechanism at the right end of the rear side of the third guide body (15).
may be attached, and the upper end center portion of the casing (IQ) may be pivotally attached to the rotating shaft of the deceleration mechanism (2) which is provided through the right end of the front side of the third guide body α5). According to the example, Figures 1 to 4
The same effect as the embodiment shown in the figure can be obtained. Further, the drawings from FIG. 7 showing another embodiment will be explained. In those drawings, the shaft 4 is a fourth guide body (23
) is the seventh motor for moving the third moving body, which will be described later, attached to the left end of the fourth guide body (2η); (b) is the first motor with an open bottom. Second imaging means (9a) and (9b) are provided, and both ends are connected to a seventh motor (2).
The actuating body is screwed into the third feed screw (corporate) which is locked to the rotating shaft and bearing of 3), the seventh motor (Daisan Feed Nesshikusha) rotates due to the operation of 23, and the actuating body - is sent in the left-right direction, and the third moving body moves in the left-right direction on the rear side of the fourth guide body 4. The walls are arranged in parallel above and below the front and rear sides of the fourth guide body □□□, respectively, to reduce friction and facilitate movement of the third moving body and the light source (described later). to make 1
A pair of linear bearings, □□□ is a light source 1, an operating body (28)%S is provided integrally at the lower end of the main body, and both ends are 8th
The actuating body (28) is screwed into the fourth feed gear 4, which is locked to the rotating shaft and bearing of the mokushi 4), and the 8th motor
The fourth feed screw (29) rotates due to the operation of the actuator, and the force of the actuating body is sent in the left and right directions, causing the light source (2) to move in the left and right direction on the front side of the fourth guide body (22I). The spot light of the blade 41 is sequentially irradiated to multiple locations on the horizontal line on the surface of the workpiece (8) within the overlapping fields of view of both the imaging means (9a) and (gb). , mll is the 3rd and 4th feed screw (goods),
9) Each operating body (25+, H is a telescopic bellows-shaped covering body that covers the left and right parts of H. With the spot light from the light source fixed at a certain irradiation point, the third moving body (b)
moves in the positive direction of the X-axis, which is the left-right direction, and as shown in FIG.
), (9b) are moved and both imaging means (9a)
, (9b) are moved, and both imaging means (
The light source (2S) sequentially moves in the positive direction of the X-axis to irradiate spot light onto multiple locations on a line on the surface of the workpiece (8) in the overlapping field 1 of 9a) and (9b). Therefore, According to the embodiment described above, it is possible to obtain the same effect as the embodiment shown in Figs. 1 to 4. In Figs. 1, 2, and 3, the optical path of the spot light from the light source is In addition to rotating by a motor, the optical path of the spot light may be rotated magnetically by an electron beam or the like.
Although a type image sensor is used, it goes without saying that an MO3 type image sensor or an image pickup tube or the like may be used.

[Brief explanation of the drawing]

The drawings show an embodiment of the measuring method of the present invention, and FIGS. 1 to 4 show one embodiment, FIG. 1 is a perspective view of the measuring device, and FIGS. 2 and 3 are views during measurement. 4 is a perspective view of a portion of FIG. 1; FIGS. 5 and 6 are a perspective view and a right side view of a portion of the measuring device in other embodiments, respectively; The drawings following FIG. 7 show still other embodiments, in which FIG. 7 is a perspective view, FIG. 8 is a right side view, and FIG. 9 is an explanatory diagram of the operation. +81...Object to be measured, (9a), (9b) ,,
Imaging means, +101, (g119- light source, L...
Line, P, P'...Irradiation point. Figure 2 Figure 3 Figure 8 Figure 911

Claims (1)

[Claims] (1) A pair of imaging means for imaging the object to be measured are provided so as to be movable in the front and rear directions, and each imaging range is movable in the left and right directions, and a light source for emitting slit light is movable in the front and back directions; and the irradiation point of the slit light is provided to be movable in the left-right direction, and the light source sequentially irradiates the slit light at a plurality of locations on a line in the left-right direction on the surface of the object to be measured within the overlapping field of view of both the imaging means, With the slit light from the light source fixed at a certain irradiation point, the imaging ranges of both the imaging means are moved in the left-right direction within a range that includes the certain irradiation point, and the image within the overlapping field of view of both the imaging means after the movement is The slit light is irradiated to a plurality of locations on the line on the surface of the object to be measured, and the overlapping fields of view are sequentially moved and the irradiation point of the slit light is moved each time the imaging means and the light source are moved in the front and rear directions. Repeatedly, the image processing means processes the images of each irradiation point of each of the slit lights on the surface of the object to be measured, taken by both the imaging means, to derive the position of each irradiation point, and A measurement method characterized by measuring the shape of the body.