JP2010060407A - Apparatus and method for recognizing button - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve the accuracy for determining two sides and a type of a button, and excellently sew the button on a to-be-sewn object by a sewing machine. <P>SOLUTION: An apparatus comprises: a plurality of light sources 9A, 9B, 9C disposed so as to irradiate a front face of the button B with irradiation lights in different directions; a camera 13 for capturing images of the front face of the button B in a state that the button B is irradiated with the irradiation lights from the light sources 9A, 9B, 9C; and a controller 15 for controlling timing when the button B is irradiated with the irradiation lights from the light sources 9A, 9B, 9C and the images are captured by the camera 13, obtaining the images of the button B captured by the camera 13 using respective irradiation lights in the different directions each time the button B by the light sources 9A, 9B, 9C is irradiated, calculating a surface normal vector n of the button B as a to-be-imaged object based on the captured images, comparing it with a reference surface normal vector, and determining two sides and the type of the button B to be imaged. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a button recognition device and a button recognition method for recognizing the type and front / back of a button.

  2. Description of the Related Art Conventionally, when a button is sewn to a sewing product by an automatic button sewing device, a button recognition device that distinguishes the front and back of the button has been used.

  For example, Patent Document 1 describes an automatic button sewing device including a button detection device for detecting the front and back of a button. This button detection device is disposed so as to be able to advance and retract at a position where it can be engaged with the upper surface of the button held by the button knob foot when the button knob foot is raised, and is engaged with the edge and center of the button upper surface. A button detecting means capable of matching, and a discriminating means for discriminating the front and back of the button by the vertical displacement of the button detecting means.

  The automatic button detection device includes, for example, a button presence / absence detection lever and a button front / back detection lever as button detection means. Such an automatic button detection device is based on whether or not the button presence / absence detection lever is pushed up by the edge of the button when the button knob foot is raised after the button is supplied to the button knob foot by the button supply arm. The presence or absence of a button on the button knob foot is detected. In addition, the automatic button detection device uses a button shape in which the central part on the front surface of the button is recessed while the central part on the back surface is flat. The front and back of the button is discriminated based on whether or not the button front / back detection lever is pushed up by the center of the button.

  Patent Document 2 discloses a button supply unit that sequentially discharges the buttons stored in the button storage unit from the button discharge port after selecting the front and back of the button by generating predetermined vibrations in the button storage unit and the movement path. The button supply apparatus provided is described, This button supply apparatus is provided with the button selection mechanism in the middle of a movement path | route. And in the button supply device, when the button passes through the button selection mechanism, the button has a flat shape by using a button shape in which the central portion on the front surface of the button is depressed and the central portion on the back surface is flat. When the back surface faces downward and the front surface faces upward, the button selection mechanism is passed. On the other hand, the button falls from the button selection mechanism downward in the button storage portion when the surface with the depression in the center portion faces downward and the back surface faces upward. Thereby, the button supply device discriminates the front and back of the button, and sequentially discharges only the button whose surface faces upward from the button discharge port.

  Furthermore, the button supply device described in Patent Document 3 is formed with a lock pin that is locked to the threading hole of the button, and a button conveying unit that supplies the button to the sewing unit of the sewing machine, and a lock pin on the lock pin. And a rotation device that presses the button onto the locking pin while rotating the button from the upper surface of the placed button. Such a button supply device rotates the button by a predetermined angle on a plane by pressing the button onto the locking pin while rotating the button with a rotating device and locking the locking pin in the threading hole of the button. Then, it is supplied to the sewing machine.

  Furthermore, Patent Document 4 discloses a button provided with an imaging means for capturing a front image by capturing an image of the upper surface of a button on which a pattern having directionality such as characters, figures, symbols, and the like is sewn on clothes. The sewing direction setting device is described. The button sewing direction setting device rotates the button so that the pattern on the upper surface of the button is directed in a predetermined direction based on the front image acquired by the imaging unit and the reference image recorded in advance for the button. To supply to the sewing machine.

Japanese Patent No. 2659073 Japanese Patent No. 2648042 Japanese Patent No. 2505289 Japanese Patent Publication No. 2-023197

  However, according to the automatic button detection device described in Patent Document 1 and the button supply device described in Patent Document 2, the front and back of the button are discriminated by the depression of the center portion on the surface of the button and the flat surface of the back surface. For example, for buttons that have the same shape on both the front and back, but have a slight difference between the front and back, such as engraving only on the front, the front and back are distinguished. Had the problem of not being able to.

  Further, according to the button supply device described in Patent Document 3, when a button with poor accuracy of the threading hole forming position is placed on the button transport unit, the locking pin is not locked to the threading hole. There has been a problem that the button is pressed onto the locking pin by the rotating device and the locking pin may be broken.

  Further, according to the button sewing direction setting device described in Patent Document 4, it is possible to determine the front and back of the button by using a stamp, an image, or the like formed on the surface of the button. When formed of a material that reflects light, it may be difficult to distinguish the background image from the button image in the acquired front image depending on the color and pattern of the button. Furthermore, according to the button sewing direction setting device described above, when the button is made of a transparent or translucent material, it is sufficient to compare the button with a reference image recorded in advance for the button. In some cases, a forward image could not be acquired. For this reason, this button sewing direction setting device has a problem that it cannot cope with the discrimination of a wide variety of buttons, for example, formed of a reflective material or a transparent or translucent material. It was. Furthermore, in the button sewing direction setting device described in Patent Document 4, for a button that has no markings or images formed on the surface of the button and has only a subtle difference in the shape of the front and back of the button, Similar to the button supply device described in Patent Documents 1 and 2, there is a problem that the front and back cannot be distinguished.

  The present invention has been made in view of these points, and is capable of improving the accuracy of discriminating the front and back of the button and the type thereof, and capable of sewing the button on the sewing product with a finished finish with a sewing machine. And a button recognition method.

  In order to achieve the object, the button recognition device according to claim 1 is characterized in that a plurality of light sources arranged so that irradiation light is irradiated from different directions with respect to the front surface of the button, and An imaging device that captures an image of the front surface of the button in a state in which irradiation light from each light source is irradiated, and controls irradiation light irradiation from each light source and imaging timing of the imaging device, and imaging by the imaging device Obtaining a captured image of the button for each irradiation light from different directions by each light source, calculating a surface normal vector of the button to be imaged based on each captured image, and the front surface of the button to be imaged And a control device for discriminating the type and front / back of the button to be imaged as compared with the reference surface normal vector calculated in advance.

  According to the first aspect of the present invention, the surface normal vector for every pixel of each captured image is obtained using each captured image acquired by irradiation of irradiation light from different directions by a plurality of light sources. Thus, the three-dimensional shape of the button can be obtained. Therefore, even if the shape difference between the front and back surfaces of the button and the type of button is subtle, it is determined whether the button front and back and the button being imaged are the same type as the desired button. can do.

  According to a second aspect of the present invention, there is provided the button recognition device according to the first aspect, wherein the control device is configured to have the surface normal vector of the entire front surface or at least a part of the outer periphery of the button. It is in the point which calculates.

  According to the second aspect of the present invention, the control device can further improve the discrimination accuracy of the front and back of the button and the type by calculating the surface normal vector for the entire front surface of the button. On the other hand, the control device can reduce the area for calculating the surface normal vector by calculating the surface normal vector for at least a part of the outer periphery of the front surface of the button. For this reason, the control device can improve the discrimination accuracy of the front and back of the button and the type, can shorten the calculation time, and can discriminate the front and back and the type of the button more efficiently. .

  According to a third aspect of the present invention, in the button recognition device according to the first or second aspect, the control device irradiates the button with irradiation light in order from each light source. The imaging device captures the front surface of the button for each irradiation of irradiation light from each irradiation direction, and acquires the captured image for each irradiation light from each irradiation direction.

  According to the third aspect of the present invention, the light is emitted to the button in turn by each light source, and an image is picked up for each irradiation of the light by each light source by the camera. A captured image for each irradiation light can be easily acquired, whereby the time required for the determination process can be shortened, and the front and back and the type of the button can be determined more efficiently.

  The button recognition device according to a fourth aspect of the present invention is characterized in that, in the button recognition device according to the first or second aspect, a light source that emits irradiation light of a different color is used as each of the light sources. The control device images the button by the imaging device in a state in which the button is simultaneously irradiated with light from the light sources, extracts the components of the colors from the captured image, and outputs the components for each light emitted from the light sources. The captured image is acquired.

  According to the fourth aspect of the present invention, since the control device images the upper surface of the button according to the state in which the light is irradiated on the button simultaneously by each light source, the time for recognizing the button can be shortened. , The front and back of the button and the type can be discriminated more efficiently.

  A feature of the button recognition method according to the invention of claim 5 is that the front surface of the button is irradiated with irradiation light from a plurality of irradiation directions, and the front surface of the button is irradiated each time irradiation light from each irradiation direction is irradiated. The surface normal vector of the button that is the imaging target is calculated based on the captured image of the button for each irradiation light from each irradiation direction, and is calculated in advance in front of the imaging target button. Compared with the reference plane normal vector, the type and front / back of the button to be imaged are discriminated.

  According to the fifth aspect of the present invention, it is possible to obtain a surface normal vector for every pixel of each captured image using each captured image acquired by irradiation of irradiation light from a plurality of irradiation directions. Thereby, the three-dimensional shape of the button can be obtained. For this reason, it is possible to determine whether the front and back and the button to be imaged are the same type as the desired button even when the difference between the curved shape of the front and back of the button and the shape of different buttons is small. .

  According to the button recognizing device and the button recognizing method of the present invention, it is possible to improve the accuracy of discriminating the front and back of the button and the type thereof, and as a result, the button can be sewn with good finish on the sewing product by the sewing machine.

  Hereinafter, an embodiment of a button recognition apparatus according to the present invention will be described with reference to FIGS.

  FIG. 1 is a schematic perspective view showing a button supply device and a sewing machine including a button recognition device according to the present embodiment.

  As shown in FIG. 1, the button recognition device 1 is provided in a button supply device 3 that supplies a button B to a sewing machine 2.

  The button supply device 3 includes a cylindrical first button supply unit 5, and a first button supply unit 5 has an inner wall surface formed on a part of an upper edge from the bottom surface of the first button supply unit 5. A spiral passage 5b for conveying the button B to the one discharge port 5a is formed. And the 1st button supply part 5 raises the button B accommodated in the bottom face part along the channel | path 5b by predetermined | prescribed slight vibration, and conveys it to the 1st discharge port 5a, and it is below from the 1st discharge port 5a. It is designed to be dropped.

  A disk-shaped second button supply unit 6 is disposed below the first discharge port 5a in the first button supply unit 5, and the second button supply unit 6 includes a disk-shaped rotating plate 6a and a rotating plate. A support 6b that covers the peripheral edge and side surface of the bottom surface of the plate 6a and accommodates the rotating plate 6a is provided. At least three (eight in the present embodiment) cutouts 6c are formed at the peripheral edge of the rotary plate 6a at the same interval in the circumferential direction, and the second button supply unit 6 includes the cutouts. The button B dropped from the first outlet 5a is accommodated by a concave button accommodating portion 6d formed surrounded by 6c and the support 6b. The rotating plate 6a is intermittently rotated in the circumferential direction by a driving means such as a motor inside the support 6b, and the button B accommodated in each button accommodating portion 6d is rotated horizontally by the rotation of the rotating plate 6a. It is transported in the transport path.

  The support body 6b is formed with a second discharge port (not shown) for dropping and discharging the button B conveyed in the button accommodating portion 6d by the rotation of the rotating plate 6a below the second button supply portion 6. Yes. The second discharge port is a position facing the notch 6c when stopped during the intermittent rotational movement of the rotating plate 6a, and the first discharging port 5a in the support 6b with the rotation center of the rotating plate 6a interposed therebetween. It is formed at a position opposite to the lower side.

  Then, the second button supply unit 6 stops when one button storage unit 6d is positioned below the first discharge port 5a, and rotates after storing the button B dropped from the first discharge port 5a in the button storage unit 6d. When the adjacent button storage portion 6d is positioned below the first discharge port 5a, the stop is stopped. Further, the second button supply unit 6 is configured to drop and discharge the button B from the second discharge port when the notch 6c is positioned on the upper surface of the second discharge port by the rotation of the rotating plate 6a.

  A button that is provided between the second button supply unit 6 and the sewing machine 2 in the vicinity of the second discharge port and that is supplied to the sewing machine 2 by correcting the position of the button B stored in the button storage unit 6d in the planar shape. A position correcting device 7 is provided. The button position correcting device 7 has a transfer arm 7a for transferring the button B, and a locking pin 7b that is locked to a button hole formed in the button B protrudes from the top surface of the distal end of the transfer arm 7a. Is formed. The transfer arm 7a is configured such that the tip portion reciprocates between the lower portion of the second discharge port and the sewing machine 2 by a driving means (not shown), and when the tip portion is positioned below the second discharge port, The button B discharged from the second discharge port is received at the tip.

  A position correcting member 7c that is rotated and moved up and down by driving means such as a motor and a cylinder (not shown) is provided above the second discharge port. The position correcting member 7c has a button B at the tip of the transport arm 7a. When it falls, it descends while rotating and presses the lower end of the position correcting member 7c against the front surface (upper surface) of the button B. As a result, the position correction device rotates the button B at the tip of the locking pin 7b to lock the button hole to the locking pin 7b of the transport arm 7a.

  The transport arm 7a holds the button B at the tip by locking the button hole to the locking pin 7b, and transports the button B to the sewing machine 2 in this state.

  As illustrated in FIG. 2, the button recognition device 1 includes a lighting device 10 including a plurality of (three in the present embodiment) light sources 9A, 9B, and 9C (9) that irradiate the upper surface of the button B. Have. The illuminating device 10 is between the accommodation position of the button B from the 1st discharge port 5a in the conveyance path | route of the button B above the 2nd button supply part 6, and the discharge position of the button B from a 2nd discharge port. The rotating plate 6a is disposed at a position facing the notch 6c when stopped during intermittent rotation of the rotating plate 6a.

  As shown in FIGS. 2 and 3, each light source 9 is opposed to the button housing portion 6d at a predetermined position so that irradiation light is irradiated on the upper surface of the button B from different irradiation directions. Each light source 9 is integrally held by an annular support 11.

  Above the lighting device 10, a camera 13 is fixed and arranged as an imaging means for picking up the upper surface of the button B. As shown in FIG. 4, the camera 13 is provided on the support 11 in the lighting device 10. The upper surface of the button B is imaged through the opening. Note that the position of the camera 13 does not have to be above the illumination device 10 as long as the irradiation light of each light source 9 can capture the reflected light reflected on the upper surface of the button B.

  As illustrated in FIG. 5, the button recognition device 1 includes a control device 15 that controls the operation of each unit of the button recognition device 1. The control device 15 includes a CPU 16, and the CPU 16 is connected to the camera 13 via an analog / digital converter (A / D converter) 17 and is connected to the camera 13 via a camera control unit 18. ing. The control device 15 is connected to each light source 9 via the light source control unit 20. Further, the control device 15 is connected to the control unit 21 of the sewing machine 2 and the button supply device 3 through an interface (I / F) 19, and is connected to each light source 9 through the light source control unit 20. Yes. The control device 15 is provided with an image memory 22, a database memory 23, and a work memory 25, which are connected to the CPU 16, respectively. The database memory 23 is calculated in advance from the captured image in front of the button B to be imaged. A reference plane normal vector on the upper surface of the button B is stored for each pixel of the captured image. Further, the captured image of the button B captured by the camera 13 is digitized by the A / D converter 17 and then stored in the image memory 22.

  Furthermore, the control device 15 has an image processing program memory 26 in which an image processing program is stored. Based on the image processing program, the control device 15 acquires a captured image for each irradiation from the irradiation direction by each light source 9. Based on the captured image, the surface normal vector n of the button B to be imaged is calculated. For example, when the upper surface of the button B is illuminated by the light source 9 from the θ direction with reference to the surface normal vector n as shown in FIG. 6, the intensity L of the light source 9, the light source vector s, and the upper surface of the button B The surface normal vector n is calculated using the reflectance ρ. Then, the control device 15 compares the calculated surface normal vector n with the reference surface normal vector of the button B being imaged, and determines the type and front / back of the button B being imaged. It is like that.

  Next, the button recognition method by the button recognition apparatus 1 according to the present embodiment will be described in detail.

  After the button B discharged from the first discharge port 5a of the first button supply unit 5 is stored in the button storage unit 6d in the second button supply unit 6, the button B is conveyed by the rotation of the rotating plate 6a and is pressed. The controller 15 of the button recognition device 1 starts the button B recognition operation.

  As shown in FIG. 7, first, the control device 15 turns on the first light source 9 </ b> A among the light sources 9 to irradiate the upper surface of the button B (ST <b> 1), and the camera 13 irradiates the first light source 9 </ b> A. The upper surface of the button B is imaged by light irradiation (ST2). Subsequently, the control device 15 turns off the first light source 9A (ST3), and stores the captured image in the image memory 22 (ST4). Thereafter, the control device 15 determines whether or not the imaging by the irradiation of the irradiation light of all the light sources 9 is completed (ST5), and when it is determined that the imaging is not completed (No in ST5), the remaining second The light source 9B is turned on, and ST1 to ST4 are repeated. If the control device 15 repeats these steps (ST1 to ST4) from the first light source 9A to the third light source 9C and determines that all the light sources 9 are turned on in ST5 (Yes in ST5). ), The captured image is transferred from the image memory 22 to the work memory 25 (ST6), and surface normal vectors are calculated for all pixels of the captured image (ST7).

  Regarding the calculation of the surface normal vector, as shown in FIG. 8, first, the control device 15 sets h = 1 (ST71), and calculates the surface normal vector of the h pixel among all the pixels of the captured image to be calculated. (ST72).

  Here, the calculation target of the surface normal vector n on the upper surface of the button B in the control device 15 may be the entire front surface of the button B as shown in FIG. Further, as shown in FIG. 9B, only a part of the outer periphery of the button B or the entire front surface may be imaged, and a part of the outer periphery of the button B may be calculated. Furthermore, as shown in FIG. 9C, the entire front surface of the button B may be imaged, and only the entire outer periphery of the button B may be calculated.

  As shown in FIG. 10, when the position of each pixel of the image captured by the CCD or CMOS which is the light receiving element of the camera 13 is (i, j) in the xyz coordinates, the surface normal vector n is expressed by Equation 1. Is done.

ここで、ａ_ｉｊ、ｂ_ｉｊ、ｃ_ｉｊは、それぞれ、面法線ベクトルｎのｘ，ｙ，ｚ成分である。

_{Here, a ij, b ij, c} ij , respectively, x the surface normal vector n, y, and z components.

  Further, since the position of each light source is determined in advance, as shown in FIG. 10, if the light source 9 is k (k = 1 to 3), the elevation angle of the light source vector s is α, and the azimuth angle is β, Since the elevation angle α and the azimuth angle β are predetermined and known depending on the position where each light source k is disposed, the light source vector s is expressed by Equation 2. The light source vector s is a unit vector having a length of 1.

また、ここでは、各光源ｋからは、ボタンＢに対して平行光線が照射され、各光源ｋの仰角αおよび方位角βは、各光源の受光位置（ｉ，ｊ）により変化せず同一であるものとする。

In addition, here, parallel light beams are emitted from each light source k to the button B, and the elevation angle α and azimuth angle β of each light source k are the same without changing depending on the light receiving position (i, j) of each light source. It shall be.

  Here, since the light source vector s is a unit vector,

となり、仰角αｋ、方位角βｋより、光源ベクトルｓを表す数式２を数式４のように変形することができる。

Thus, from the elevation angle αk and the azimuth angle βk, Equation 2 representing the light source vector s can be transformed as Equation 4.

一方、画素（ｉ，ｊ）における光源９による輝度Ｘｉｊｋは、ランベルトの余弦則により、数式５によってあらわすことができ、数式５に数式１および数式２を代入すると数式６が得られる。

On the other hand, the luminance Xijk from the light source 9 in the pixel (i, j) can be expressed by Equation 5 according to Lambert's cosine law, and Equation 1 and Equation 2 are substituted into Equation 5 to obtain Equation 6.

ここで、光源ベクトルｓは数式３に示すように単位ベクトルであり、ｃｉｊ＝１とすることにより、輝度を表す数式５は、数式７に変形することができる。

Here, the light source vector s is a unit vector as shown in Equation 3, and by setting cij = 1, Equation 5 representing luminance can be transformed into Equation 7.

そして、各光源９を１、２、３とし、各光源９から撮像した結果を数式６に代入すると、数式８、数式９、数式１０が得られる。

Then, when each light source 9 is set to 1, 2, and 3, and the result of imaging from each light source 9 is substituted into Equation 6, Equation 8, Equation 9, and Equation 10 are obtained.

ここで、数式８、数式９、数式１０の右辺の分母を消去するために、数式９を数式８で割り（Ｘｉｊ２／Ｘｉｊ１）、数式１０を数式８で割る（Ｘｉｊ３／Ｘｉｊ１）と、数式１１、数式１２が得られる。

Here, in order to delete the denominator of the right side of Formula 8, Formula 9, and Formula 10, Formula 9 is divided by Formula 8 (Xij2 / Xij1), Formula 10 is divided by Formula 8 (Xij3 / Xij1), Formula 11 , Equation 12 is obtained.

そして、数式１１および数式１２の連立方程式を解くと、ａｉｊは、数式１３によって求められ、ｂｉｊは、数式１４によって求められ、ｃｉｊ＝１であるので、これにより画素（ｉ，ｊ）における面法線ベクトルｎを求めることができる。

Then, when solving the simultaneous equations of Equations 11 and 12, aij is obtained by Equation 13 and bij is obtained by Equation 14, and cij = 1, and thus the surface method at pixel (i, j). A line vector n can be obtained.

なお、数式１３および１４において、ａ_ｋ、ｂ_ｋ、ｃ_ｋは、数式１２により、
ａ_ｋ＝ｃｏｓα_ｋｃｏｓβ_ｋ
ｂ_ｋ＝ｃｏｓα_ｋｓｉｎβ_ｋ
ｃ_ｋ＝ｓｉｎα_ｋ
として算出される。

In Equations 13 and 14, a _k , b _k , and c _k are expressed by Equation 12,
a _k = cos α _k cos β _k
b _k = cos α _k sin β _k
c _k = sin α _k
Is calculated as

  Subsequently, the control device 15 determines whether or not h is smaller than m when the total number of pixels of the captured image to be calculated is m (ST73), and when it is determined that h is smaller than m (ST73) In ST73, Yes), h = h + 1 is set, the h-th pixel surface normal vector is calculated again (ST72), and it is determined whether h is smaller than m (ST73). On the other hand, when determining that h is not smaller than m in ST73 (No in ST73), control device 15 ends the process of calculating the surface normal vector. In this way, the control device 15 calculates the surface normal vector for the entire captured image, the entire front surface of the button B to be calculated as described above, a part of the outer peripheral edge, or all the pixels of the entire outer peripheral edge.

  Further, in the case where the surface normal vector n is obtained in the control device 15, for example, for the diffuse reflection component of the irradiated light on the upper surface of the button B due to the material, processing, etc. of the upper surface of the button B, such as a metallic button B When the specular component (regular reflection) cannot be ignored, the reflectance ρ of the upper surface of the button B is acquired in advance and stored in the database. Further, as shown in FIG. 11, by attaching a polarizing filter 28 to the lens of the camera 13 or attaching a polarizing filter 29 to the front surface of the light source 9, only the diffuse reflection component is received by the camera 13. Also good. Thereby, the control apparatus 15 can calculate the exact surface normal vector n.

  Furthermore, when the light source 9 that is not the point light source 9 having directivity characteristics, such as an LED, is used as each light source 9, the directivity characteristics are removed by attaching the diffusion filter 30 to the front surface of the light source 9. Thus, the control device 15 can calculate an accurate surface normal vector n.

  Subsequently, the control device 15 performs a surface normal vector comparison process (ST8). Regarding the surface normal vector comparison processing, as shown in FIG. 12, the control device 15 first extracts the reference surface normal vectors of all the pixels of the button B to be imaged from the database and calculates them by pattern matching. Compared with the surface normal vector n of all pixels in the captured image (ST81), the coincidence ratio between the reference surface normal vector of all pixels and the calculated surface normal vector is calculated (ST82).

  Next, based on a predetermined threshold value, for example, the control device 15 determines whether or not the coincidence ratio between the reference surface normal vector of all pixels and the calculated surface normal vector n is greater than 80%. Is determined (ST9). If the control device 15 determines that the coincidence rate is greater than 80% (Yes in ST8), the control device 15 determines that the surface of the button B is facing upward (ST10), and uses the I / F 19 to The discrimination result is output to the control unit 21 of the sewing machine 2, and the transport arm 7a of the button position correcting device 7 is driven to transport the button B to the sewing machine 2 (ST11). Next, the control unit 21 of the sewing machine 2 performs sewing of the button B using the button B conveyed by the conveyance arm 7a.

  On the other hand, if it is determined in ST8 that the coincidence rate is not greater than 80% (No in ST8), the control device 15 determines that the back surface of the button B is facing upward or the type of the button B is different ( ST12), the button B transported by the transport arm 7a is transported to a reject position (not shown) and rejected (ST13).

  According to the present embodiment, it is possible to obtain the surface normal vector n for every pixel using each captured image acquired by irradiation from the irradiation direction by the plurality of light sources 9A, 9B, 9C. The three-dimensional shape of B can be obtained. For this reason, even if the difference between the curved shapes of the front and back surfaces of the button B and the shapes of the different buttons B is small, it is determined whether or not the button B that is the front and back surfaces and the imaging target is the same type as the desired button B. can do.

  Therefore, according to the button recognition device 1 of the present embodiment, it is possible to improve the discrimination accuracy of the front and back sides and the type of the button B. As a result, the button B can be sewn with good finish to the sewing product by the sewing machine 2. .

  In addition, the control device 15 can further improve the discrimination accuracy of the front and back sides and the type of the button B by calculating the surface normal vector n for the entire front surface of the button B. Furthermore, the control device 15 can reduce the area for calculating the surface normal vector n by calculating the surface normal vector n for a part or all of the outer peripheral edge of the front surface of the button B. For this reason, the control device 15 can improve the discrimination accuracy of the front and back sides and the type of the button B, can shorten the calculation time, and more efficiently discriminates the front and back sides and the type of the button B. be able to.

  Further, the light source 9 sequentially irradiates the irradiation light to the button B, and the camera 13 captures an image every time the light source 9 irradiates the irradiation light. Therefore, the control device 15 performs the irradiation for each irradiation light from each irradiation direction. A captured image can be easily acquired, whereby the determination process can be shortened, and the front and back and the type of the button B can be determined more efficiently.

  Furthermore, according to the present embodiment, each captured image is captured by the fixed camera 13, so that the captured images are captured as compared with the case where the captured images for each irradiation from each irradiation direction are captured using a plurality of cameras 13. There is no need to associate ranges, the determination process can be shortened, and the front and back and the type of the button B can be determined more efficiently.

  Subsequently, a second embodiment of the present invention will be described with reference to FIG.

  FIG. 13 is a schematic side view showing the waist of the button recognition device 1 according to the second embodiment. Here, in the second embodiment, detailed description of the same configuration as that of the first embodiment will be omitted, and description will be made using the same reference numerals.

  As illustrated in FIG. 13, the button recognition device 1 in the second embodiment includes four or more (in the second embodiment) arranged at positions where the irradiation light is irradiated from different irradiation directions with respect to the upper surface of the button B. Are provided with five light sources 9A, 9B, 9C, 9D, and 9E (hereinafter collectively referred to as reference numeral 9). The number of light sources 9 is determined in consideration of the shape and surface characteristics of the upper surface of the button B.

  Next, a button B recognition method of the button recognition device 1 according to the second embodiment will be described.

  The control device 15 takes an image of the upper surface of the button B by the camera 13 every time the irradiation light is emitted from the irradiation direction by each light source 9, and stores each of the taken imaging screens in the image memory 22. And the control apparatus 15 calculates the surface normal vector n of the upper surface of the button B used as the imaging object based on an image processing program.

  Here, as shown in FIG. 13, the camera 13 reflects light reflected from a certain part on the upper surface of the button B from the light sources 9B, 9C, and 9D, and the upper surface of the light source 9B, 9C, 9D, the button B, and the camera 13. Therefore, only the diffuse reflection component is received. On the other hand, for the reflected light reflected from the upper surface of the button B from the light source 9A, the camera 13 receives only the regular reflection component from the positional relationship between the light source 9A, the upper surface of the button B and the camera 13. Further, the camera 13 cannot receive the reflected light reflected by the button B from the light source 9E due to the cast shadow.

  At this time, the control device 15 distinguishes the regular reflection component from the diffusion component based on the luminance level or color, and calculates the surface normal vector n from the reflected light data of the corresponding pixel in the captured image of the light source 9A. Do not use. Further, the control device 15 displays the reflected light data of the corresponding pixel in the captured image of the light source 9E as the light source 9E that does not receive the reflected light for the luminance portion (dark portion) that does not reach the predetermined threshold value. It is not used for calculating the normal vector n. The threshold value is set in consideration of the color of the upper surface of the button B.

  Therefore, the control device 15 calculates the surface normal vector n for the corresponding pixel using the captured image for each irradiation in the irradiation direction by the light sources 9B, 9C, and 9D.

  Then, the control device 15 compares the calculated surface normal vector n with the reference surface normal vector, and the front surface of the button B is facing upward, or the back surface of the button B is facing upward, or the button B Determine if the type is different. When the control device 15 determines that the surface of the button B is facing upward, the control device 15 drives the transfer arm 7a of the button position correction device 7 via the interface (I / F) 19 to operate the button B. While conveying to the sewing machine 2, the determination result is output to the control unit 21 of the sewing machine 2. Next, when the determination result that the surface of the button B is facing upward is input, the control unit 21 of the sewing machine 2 sewes the button B using the button B transported by the transport arm 7a.

  On the other hand, when the control device 15 determines that the back surface of the button B is facing upward, the control device 15 transports the button B transported by the transport arm 7a to a removal position (not shown) and removes it.

  According to the second embodiment, the control device 15 can calculate the surface normal vector n using only diffusely reflected light, and thus calculates the surface normal vector n without acquiring the reflectance in advance. be able to.

  In addition, since the control device 15 can calculate the surface normal vector n using reflected light data having a luminance equal to or higher than a predetermined threshold, it is possible to calculate a more accurate surface normal vector n. Become.

  Therefore, according to the button recognition device 1 of the second embodiment, it is possible to improve the discrimination accuracy of the front and back sides and the type of the button B. As a result, the button B is sewn with good finish to the sewing product by the sewing machine 2. Can do.

  In addition, this invention is not limited to the said both embodiment, A various change is possible as needed.

  For example, the button recognition device 1 according to the first embodiment is provided in the button supply device 3 including the first button supply unit 5, the second button supply unit 6, and the button position correction device 7, but is not limited thereto. Is not to be done.

  Moreover, in both above-mentioned embodiment, although the front surface of the button B is imaged in order for every irradiation of the irradiation light from the irradiation direction by each light source 9, this invention is not limited to this. For example, as each light source 9, a light source 9 that emits irradiation light of different colors such as R, G, and B is used, and the control device 15 controls the button B according to the state in which the button B is irradiated with irradiation light simultaneously by each light source 9. The upper surface may be imaged, components of each color may be extracted from the captured image, and a captured image for each irradiation direction by each light source 9 may be acquired. Thereby, the button recognition apparatus 1 can obtain | require the surface normal vector n for every pixel using each captured image acquired by irradiation from the irradiation direction by the several light source 9, and, thereby, button B A three-dimensional shape can be obtained. In addition, since the upper surface of the button B is imaged while the buttons B are simultaneously irradiated by the light sources 9, the time for recognizing the button B can be shortened, and the front, back, and type of the button B can be determined more efficiently. can do.

  Furthermore, in both of the above-described embodiments, a plurality of light sources 9 are used to obtain captured images for each irradiation light from a plurality of irradiation directions. However, the present invention is not limited to this, and a plurality of images are obtained in advance. You may make it determine the irradiation direction and move the one light source 9 so that irradiation light may be irradiated from each irradiation direction.

Schematic perspective view showing a button supply device and a sewing machine provided with an embodiment of a button recognition device according to the present invention. Schematic top view which shows the 2nd button supply part and button recognition apparatus in the button supply apparatus of FIG. Schematic perspective view showing the button recognition device of FIG. Schematic sectional view showing the button recognition device of FIG. The block diagram which shows the structure of the button recognition apparatus of FIG. Schematic side view showing the relationship between buttons, light source and camera The flowchart which shows the button recognition method in the button recognition apparatus of FIG. FIG. 7 is a flowchart showing a surface normal vector calculation process in the button recognition method of FIG. (A)-(c) is a schematic plan view which shows the imaging target in a button XYZ axis coordinates indicating the relationship between the light source of FIG. 1 and one pixel FIG. 1 is a schematic side view showing a case where a polarizing filter and a diffusion filter are mounted in the recognition apparatus of FIG. FIG. 7 is a flowchart showing a surface normal vector comparison process in the button recognition method of FIG. The schematic side view which shows the relationship between the camera of the button recognition apparatus in 2nd Embodiment, a button, and a light source.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Button recognition apparatus B button 9A, 9B, 9C Light source 10 Illumination apparatus 11 Support body 13 Camera 15 Control apparatus 16 CPU
17 A / D converter 18 Camera control unit 19 Interface 20 Light source control unit 21 Control unit 22 Image memory 23 Database memory 25 Work memory 26 Image processing program memory

Claims (5)

A plurality of light sources arranged so that irradiation light is irradiated from different directions with respect to the front surface of the button,
An imaging device that images the front surface of the button in a state in which irradiation light from each of the light sources is irradiated;
Controls the irradiation timing of the irradiation light from each of the light sources and the imaging timing of the imaging device, obtains a captured image of the button for each irradiation light from different directions by the light sources by imaging by the imaging device, The surface normal vector of the button that is the imaging target is calculated based on the captured image, and compared with the reference surface normal vector that is calculated in advance on the front surface of the imaging target button. A button recognition device comprising: a control device for discriminating between.   2. The button recognition device according to claim 1, wherein the control device calculates the surface normal vector of the entire front surface or at least a part of the outer periphery of the button.   The control device irradiates the button with irradiation light in order from each light source, and images the front surface of the button for each irradiation light from each irradiation direction by the imaging device, from each irradiation direction. The button recognition apparatus according to claim 1, wherein the captured image is acquired for each irradiation light. As each of the light sources, a light source that emits irradiation light of a different color is used,
The control device picks up an image of the button by the image pickup device in a state in which the button is simultaneously irradiated with light from the light sources, extracts components of the colors from the picked-up image, and outputs each light emitted from the light sources. The button recognition apparatus according to claim 1, wherein the captured image is acquired. Irradiate light from multiple irradiation directions to the front of the button,
For each irradiation of irradiation light from each irradiation direction, image the front of the button,
Based on the captured image of the button for each irradiation light from each irradiation direction, calculate the surface normal vector of the button to be imaged,
A button recognition method, wherein the type and front / back side of the imaging target button are discriminated by comparing with a reference surface normal vector calculated in advance on the front side of the imaging target button.

Images