JPH105465A - Quilting method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To follow a boundary of an arbitrary pattern on a ground fabric, and form stitches along the boundary. SOLUTION: In a quilting-processing device 1, cameras 5a, 5b are disposed in inclined conditions to be adjacent to a stitch mechanism 8 in a perpendicular condition to a ground fabric 2, the fabric 2 within a view field is regulated to be within a camera focal range by a subject presser from the stitch mechanism 8 side, while a pattern 4 in the fabric 2 is image-picked up by the cameras 5a, 5b, a boundary detection circle of a similar radius to a stitch width is generated on a picture image of the pattern 4 based on stitch information, so that picture image is scanned along a circumference, and the next stitch position is detected based on brightness change and a deviation angle between a stitch vector from a present stitch position to an estimated stitch position on the circumference and a previous stitch vector.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a quilting method for performing stitching along a boundary (outline) of a pattern while reading the boundary of the pattern of one or more base cloths by an image processing technique.

[0002]

2. Description of the Related Art An ordinary quilting cloth is sewn by a geometric sewing pattern such as a straight line or a zigzag stitch, and is not sewn along a pattern of a fabric. On the other hand, according to the technique of mechanical embroidery, a desired embroidery pattern is applied to the fabric, and the pattern of the embroidery pattern at that time is designed in advance before the embroidery process. Therefore, the machine embroidery technique does not embroider along the given pattern, tracking the border (outline) of the pattern, and cannot handle free patterns other than pattern design. .

[0003] By the way, with the diversification or individualization of clothing, garments such as characters and figures are frequently used in cloths and clothing, and quilting is performed along these patterns. Cloth is also valuable as a new form of fabric. However, as noted above, free quilting along any handle is not currently achievable by mechanical embroidery techniques.

[0004]

OBJECTS OF THE INVENTION It is, therefore, an object of the present invention to enable the construction of a quilted fabric by tracking the boundaries of any pattern of the base fabric and stitching along the boundaries. The quilting cloth is usually sewn with a core material or cotton sandwiched between two cloths, but in this specification, stitching is performed along the border of the handle of one base cloth. It shall include stab stitches.

[0005]

The quilting method according to the present invention is based on the premise of a quilting device. The quilting apparatus fixes a base cloth on an XY table of an XY guide unit, captures a pattern of the base cloth with a camera, detects a boundary of the pattern from an image of the pattern by an image processing unit, and stitches on the boundary. After the position is determined, the XY guide unit is driven by the control unit which receives stitch position data as input, and the XY table is moved to guide the stitch position of the base fabric under the stitch mechanism needle. Then, the stitch mechanism is operated by the control unit to perform stitching at the stitch position of the base cloth.

According to the quilting method of the present invention, in a quilting processing apparatus, a camera is arranged beside a stitch mechanism perpendicular to a base cloth, and the camera is opposed to the base cloth in an inclined state. When the boundary of the pattern of the base fabric is imaged, the subject press is lowered from the stitch mechanism side, and while the base fabric in the field of view of the camera is regulated within the focus range of the camera, the design is imaged by the camera.

For the next stitch position, a circle for detecting a boundary having a radius equal to the stitch width is generated on the pattern image based on the stitch information, and the image is scanned along the circumference of the circle. It is detected from the amount of change in luminance on the circumference and the argument between the stitch vector from the current stitch position to the next stitch position candidate on the circumference and the previous stitch vector.

In particular, when the deviation angle is large in the detection process, the quilting processing method of the present invention reduces the radius of the circle for detecting the boundary based on the stitch information, re-determines the next stitch position, and obtains a new stitch position. When the declination of the stitch vector obtained in step (1) becomes small, the stitch is executed with the radius of the circle at that time as the stitch width.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG.
Of FIG. Quilting equipment 1
Is an XY guide unit 3 for fixing the base cloth 2 and guiding the base cloth 2 in the XY directions on the XY table 10, for example, two cameras 5 a, 5 b, and images of the pattern 4 of the base cloth 2. The image processing unit 6 detects the boundary (contour) of the pattern 4 from the image data, detects the stitch position on the boundary, and drives the XY guide unit 3 using the stitch position data from the image processing unit 6 as input.
A control unit 7 for moving the table 10 to guide the stitch position of the base cloth 2 to the needle stab position. Under the control of the control unit 7, stitching (sewing) the base cloth 2 guided to the needle stab position.
Is formed by a stitch mechanism 8 for performing the following.

Next, FIG. 2 shows an internal configuration of the image processing section 6. The two cameras 5a and 5b are both R.
This is a GB color CCD color camera. To prevent interference with the stitch mechanism 8, the stitch mechanism 8 is located on the left and right sides of the stitch mechanism 8 when viewed from the front of the stitch mechanism 8.
, For example, about 30 degrees with respect to the vertical. The distance between the cameras 5a and 5b and the base cloth 2 in the field of view is not constant due to the inclination of the camera lens, the thickness of the base cloth 2, and the like, and the image may not be clearly displayed. In order to make the depth of field as deep as possible, it is set as the most squeezed state.

The illuminations 9a and 9b are provided by the cameras 5a and 5b.
b in order to obtain the amount of light required for image processing described below even when the apertures of the cameras 5a and 5b are fully closed, and to obtain white light capable of coping with the base cloth 2 on a white background. , A halogen white illumination with a large amount of light is used.
The illumination light from each of the illuminations 9a and 9b is
The light is reflected on the surface of the base cloth 2 through
After passing through 1 and 12, they enter the corresponding cameras 5a and 5b, respectively. Thereby, the reflected light from the texture of the surface of the base cloth 2 is suppressed, and the ground color of the base cloth 2 and the color of the surface of the pattern 4 can be accurately imaged.

The color image signals from the cameras 5a and 5b are selected by a camera switch 13 and sent to a color separator 14. The color separator 14 sends the color image signal to the color monitor 15 to display the captured image, separates the color image signal into a color part to be extracted as an image and a color part not to be extracted as a binary (black and white). ) Converting the image into an image signal
Output to Note that the color monitor 15 is provided with a color separator 14.
Each camera 5
The images from a and 5b and the color-separated images are displayed in color. The color to be extracted is pre-teached to the color separator 14 before stitching.

Each of the cameras 5a and 5b has an automatic light amount adjusting function and an automatic white balance adjusting function as its own functions. When these functions operate automatically, the color changes depending on the amount of light of the base cloth 2 and the type of color projected on the camera, and therefore, these functions are all set to an off state.

FIG. 3 shows the field of view of the cameras 5a and 5b. The respective fields of view overlap each other, and the central portion of the overlap is adjusted to be the position of the needle 18 of the stitch mechanism 8 (needle position). In each of the cameras 5a and 5b, the direction of the arrow is set to be on the upper side of the image (upper side on the monitor). The image processing device 16 includes two cameras 5a, 5b
By taking images from and compositing them,
It is virtually handled as one image. The visual field range of the synthesized image is X: 26 [mm] × Y: 700 [m] using an experimental apparatus.
m].

Next, the image processing device 16 detects a stitch position from one composite image by an image processing technique, and sends the XY control data of the stitch position to the control unit 17. Therefore, the control unit 17 operates the XY guide unit 3 and the stitch mechanism 8 based on the XY control data, and performs stitching at a predetermined stitch width (cloth feed pitch) at the boundary position of the pattern 4 of the base fabric 2. . The image processing device 16
Is constituted by a CPU, and the resolution of the image is 256 gradations of black and white. Also, the B / W monitor 17
Displays the image input to the image processing device 16 or the processed image subjected to image processing on a black and white screen.

Next, FIG. 4 shows the configuration of the XY guide section 3. The XY guide portion 3 is a portion that fixes the base fabric 2 on an XY table 10 that can be moved in the XY directions, and guides the stitch position of the handle 4 to a needle stab position directly below the needle 18 of the stitch mechanism 8, It has an X-axis feed unit 19 and a Y-axis feed unit 21. The motor controller 23 inside the control unit 7 drives the drivers 24 and 25, respectively, and drives the X-axis motor 20 and the Y-axis motor 22, respectively. The second stitch position is guided to the needle insertion position.

Next, FIG. 5 shows the stitch mechanism 8. The needle 18 of the stitch mechanism 8 moves up and down in synchronization with the rotation of the main shaft 26 to engage the upper thread 35 with the lower thread 36 of the lower thread mechanism 27 to perform a predetermined stitch, for example, a straight stitch by 200
[Stitch / min]. Therefore, the motor controller 28 inside the control unit 7 drives the spindle motor 30 via the amplifier 29. The quilting apparatus 1 detects the rotation of the main shaft 26 of the stitch mechanism 8 by the encoder 37 and synchronizes with the rotation to perform image processing and XY table 1
0 is controlled.

FIG. 6 shows the time required for each rotation of the main shaft 26 in relation to the start angle of each operation, the designated position, and the like. While the main shaft 26 makes one clockwise rotation,
A (first imaging start), B (second imaging start), C (imaging completion), D (table movement instruction position), E (table movement start instruction), and F (subject holding down instruction position) are sequentially performed.

As shown in FIG. 5, the stitch mechanism 8 includes a stitch cloth presser 31 near the needle 18 that moves in conjunction with the vertical movement of the needle 18 and a subject presser 32 that moves in conjunction with the imaging operation.
It has. The object presser 32 is driven by, for example, an electromagnetic solenoid 33, and the camera 5
a, 5b, descends before the start of imaging, contacts the upper surface of the base cloth 2 in the camera's field of view, regulates the pattern 4 of the base cloth 2 within the camera focus range (depth of field), and secures a necessary resolution. .

FIG. 7 shows a change in the position of the needle 18 on an image (camera CCD image plane) due to a change in the position of the base cloth 2 in the height direction. Since the cameras 5a and 5b are tilted,
When the base cloth 2 is shifted by 1 [mm] in the height direction, the shift of the needle position on the image is 0.5 [mm]. This shift is
Since it occurs for each camera 5a, 5b, the camera 5a, 5b
The needle position is shifted by 1 [mm] between them. The imaging object presser 32 is effective in preventing this displacement on the image.

Next, FIG. 8 shows the order (step) of following the boundary (contour) of the pattern 4 of the base cloth 2.

Stitch information generation This step is a process of setting information necessary for stitches. The condition is based on the stitch width (cloth feed pitch), as shown in FIG.
From this position, a circle (image coordinate sequence) 34 for pattern boundary detection (check target) is generated on the image, and at the same time, a table movement amount and movement vector information corresponding to each coordinate of the detection trajectory are set. In FIG. 9, since the cameras 5a and 5b are inclined, the circle 34 appears as an ellipse on the image.
Here, the radius of the circle 34 corresponds to the set value of the stitch width.

Since the quilting apparatus 1 has a function of automatically adjusting the stitch width according to the form of the handle 4, in addition to the set value of the stitch width of the basic stitch, the stitch information includes The stitch width is prepared as follows.

The set value of the stitch width of the basic stitch is 6
[Mm]: Stitch width 6, 5, 4, 3, 2, 1
Stitch information for [mm] is prepared. When the set value of the stitch width of the basic stitch is 4.8 [mm]: Stitch information for the stitch width 4.8, 4, 3, 2, 1 [mm] is prepared. When the set value of the stitch width of the basic stitch is 4.3 [mm]: Stitch information for the stitch width of 4.3, 3, 2, 1 [mm] is prepared. When the set value of the stitch width of the basic stitch is 1 [mm]: Stitch information for the stitch width of 1 [mm] is prepared.

As shown in FIG. 10, each of the cameras 5a and 5b scans an image in the direction of the XY arrow, and detects a position having the largest luminance change as an "initial stitch position".
With this function, the boundary of the pattern 4 is automatically adjusted to the needle position of the image processing unit 6. In the initial stitch position,
The stitch operation is started from the next first stitch position without performing the stitch.

Movement of initial stitch position In the process of detecting the initial stitch position, the control section 7 and the XY guide section 3 move the XY table 10 based on the coordinate data of the initial stitch position. Note that the image processing unit 6 and the control unit 7 detect the initial stitch position and move the initial stitch position by the image processing device 16.
The amount of deviation between the needle position and the boundary of the handle 4 is 0.5 [m
m], the alignment accuracy is increased by repeating the process until the number of times becomes less than or equal to
When the deviation does not fall below the allowable range, an alarm is sounded to notify the operator of the state.

Stitch position detection The image is scanned for each of the cameras 5a and 5b in accordance with the boundary locus of the pattern 4 shown in FIG. 11, and a plurality of stitch position candidates having a remarkable change in luminance are extracted. Is determined as the next stitch position.

(1) Amount of change in luminance (2) Declination between stitch vector from current stitch position to next stitch position candidate and previous stitch vector

The above item (1) includes the suppression of extraction (increase) of stitch position candidates in the same camera, the camera 5a,
This is used for assisting the evaluation of the stitch position candidate for each 5b. The item (2) is used for the process of preventing stitches (sewing direction) from going backwards and evaluating stitch position candidates for each of the cameras 5a and 5b. When the stitch position is determined from the stitch position candidates from the cameras 5a and 5b, basically, the stitch position is determined by the above item (2). When the difference between the values of (1) is large, the item of (1) is determined. Priority.

Judgment of Stitch End When the following two conditions are satisfied, it is judged that stitch is ended. The distance between the first stitch position and the next stitch position is less than the stitch width. The above condition is satisfied, and the deviation between the first stitch vector (the vector from the initial stitch position to the first stitch position) and the next stitch vector. Angle is less than the value specified by the parameter

FIG. 12 is an illustration of stitch end conditions. The judgment of the above judgment is made after confirming that the distance from the first stitch position to the next stitch position is larger than the stitch width. In addition, the stitch is further subjected to a stitch operation (stitch detection and table movement operation) once after the stitch end determination, and the stitch is ended. As a result, a position beyond the first stitch position is stopped at the end of the stitch.

Here, the control unit 7 moves the XY table 10 to the position based on the coordinate data of the position detected by the stitch position detection, and moves the stitch position of the base fabric 2 right below the needle 18. To guide.

As described above, the quilting apparatus 1
Has a function of automatic stitch width adjustment. As shown in FIG. 13, the boundary (outline) of the pattern 4 of the base cloth 2 is evaluated by a method of detecting a stitch position on an image on the circumference of a circle 34 centered on the current needle position, and the next stitch is detected. Detect the position. When this method is used, as shown in FIG. 14, when the stitch width of the pattern of the base cloth 2 is long at the set value, the pattern 4
Occurs between the boundary of the thread and the yarn path, and the shift becomes apparent at an acute corner portion.

As shown in FIG. 15, the image processing unit 6 and the control unit 7, when avoiding the above-described deviation, when the deviation angle between the previous stitch position and the next stitch position candidate is large, The radius of the circle 34 is sequentially reduced for each of the stitch information, and the boundary of the corner portion of the pattern 4 is obtained again. If the declination becomes small in such an execution process, the control unit 7 drives the XY guide unit 3 and the stitch mechanism 8 using the radius of the circle 34 to be checked at that time as the stitch width. The magnitude of the argument is compared by the angle formed by the previous stitch vector and the next stitch vector = asin (1 [mm]).
/ Radius of the circle to be checked).

Note that the above-described stitch position detection is performed in accordance with FIG.
6 is performed by the image processing. First, in the process of generating a pattern boundary detection luminance list of the camera 5a, an image is scanned in accordance with the circumference of the circle 34 with the needle position as the center, and a luminance list is created. Next, in the process of differentiating the luminance list of the camera 5a, the luminance list is differentiated by a differentiation operator to generate a luminance differential list. In the step of suppressing the non-maximum point of the luminance differential list of the camera 5a, the non-maximal point of the luminance differential list is suppressed, whereby only the maximum point of the change from the dark color to the bright direction of the image is extracted. In the process of extracting the candidate points of the next camera 5a, the candidate points are extracted according to the magnitude of the luminance differential value. The number of candidate points is specified in advance. In the step of determining the next step candidate point of the camera 5a, the argument α between the stitch vector of the candidate point and the previous stitch vector is evaluated in descending order of the luminance differential value, and the next step point is determined. The following camera 5b
The steps (1) to (4) are executed for the same, and similar processing is performed. In the step of determining the next stitch point from the last camera 5a, 5b candidate, the argument formed by the luminance differential value of the next stitch candidate point in the processing of each camera 5a, 5b and the previous stitch vector is evaluated. From the viewpoint, the next stitch point is determined.

FIG. 17 shows the determination process. First, it is determined from the evaluation of the argument whether any of the candidate points of the cameras 5a and 5b is influential. And each camera 5a,
The luminance differential value is evaluated for each image 5b, and the candidate point of the camera 5a or the camera 5b is set as the next stitch point depending on which luminance differential value is sufficiently large. In this way, the next stitch point is finally determined from the images of the two cameras 5a and 5b.

[0037]

According to the present invention, the boundary (contour) of an arbitrary pattern is tracked by the image processing technique, the next stitch position is determined based on the track, and the base fabric is automatically guided to the stitch position. The sewn is automatically performed by the stitches along the handle, so that the handle and the stitches along the border can produce high value-added cloth products. Is regulated within the focusing range of the camera by the object press for imaging,
Even if the camera is provided in an inclined state avoiding the stitch mechanism, the resolution of the image from the camera is improved, and the next stitch position is detected from the luminance change amount and the declination of the stitch vector, so that the pattern Boundary detection accuracy is good, and when the declination is larger, the next stitch position is obtained while reducing the radius of the boundary detection circle, so the stitch position is stitched along the bent part of the pattern In addition, effects such as an increase in stitch accuracy at a bent portion of the handle can be obtained.

[Brief description of the drawings]

FIG. 1 is a block diagram of a quilting apparatus according to the present invention.

FIG. 2 is a block diagram of an image processing unit.

FIG. 3 is an explanatory diagram of a field of view of two cameras.

FIG. 4 is a block diagram of an XY guide.

FIG. 5 is a front view of a stitch mechanism.

FIG. 6 is an explanatory diagram of each operation position with respect to a rotation angle of a main shaft.

FIG. 7 is an explanatory diagram of a shift of a needle position on an image with respect to a height of a base cloth.

FIG. 8 is a flowchart of following a pattern of a base cloth.

FIG. 9 is an explanatory diagram of a circle for detecting a boundary on an image.

FIG. 10 is an explanatory diagram of initial stitch position detection.

FIG. 11 is an explanatory diagram of a current stitch position and a next stitch position candidate.

FIG. 12 is an explanatory diagram of a stitch end condition.

FIG. 13 is a relative explanatory diagram of a needle position, a circle for detecting a boundary, and a pattern corner.

FIG. 14 is an explanatory diagram of a deviation between a pattern boundary and a yarn path at a corner of the pattern.

FIG. 15 is an explanatory diagram of a process of obtaining the next stitch position by reducing the radius of a boundary detection circle at a corner of a pattern.

FIG. 16 is a flowchart of image processing in the next stitch point detection process.

FIG. 17 is a flowchart of image processing in the next stitch point determination process.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Quilting processing apparatus 2 Base cloth 3 XY guide part 4 Pattern 5a, 5b Camera 6 Image processing part 7 Control part 8 Stitch mechanism 9a, 9b Lighting 31 Fabric holder 32 Subject holder 34 yen

Continued on the front page (72) Inventor Minoru Ota 4846-2, Naejima, Fukuno-cho, Higashi-Tonami-gun, Toyama Prefecture Within the Textile Research Center, Toyama Prefectural Industrial Technology Center (72) Takashi Sumiya, 662 Nojiri, Fukuno-cho, Higashi-Tonami-gun, Toyama 1 share. (72) Inventor Isao Okita 662 Nojiri, Fukuno-cho, Higashi-Tonami-gun, Toyama Prefecture 1 Inside Rosef Technology Co., Ltd.

Claims (3)

[Claims] 1. A base cloth is fixed on an XY table of an XY guide unit, a pattern of the base cloth is imaged by a camera, and a boundary of the pattern is detected from an image of the pattern of the base cloth by an image processing unit. After the stitch position is determined above, the control unit that inputs stitch position data drives the XY guide unit to move the XY table so that the stitch position of the base fabric is located below the stitch mechanism needle. After the guidance, the stitch mechanism is operated by the control unit to stitch the stitch position of the base fabric.In the quilting processing apparatus, the camera is arranged beside the stitch mechanism perpendicular to the base fabric, and the camera is mounted on the base fabric. When capturing the boundary of the pattern of the base cloth in an inclined state with respect to the cloth, the subject presser is lowered from the stitch mechanism side to restrict the base cloth in the camera's field of view within the focus range of the camera. I Reluctant, quilting method characterized by imaging by the camera the handle. 2. A base cloth is fixed on an XY table of an XY guide unit, a pattern of the base cloth is imaged by a camera, and a boundary of the pattern is detected from an image of the pattern of the base cloth by an image processing unit. After the stitch position is determined above, the control unit that inputs stitch position data drives the XY guide unit to move the XY table so that the stitch position of the base fabric is located below the stitch mechanism needle. After the guidance, the stitch mechanism is operated by the control unit to stitch the stitch position of the base fabric.In the quilting processing apparatus, the camera is arranged beside the stitch mechanism perpendicular to the base fabric, and the camera is mounted on the base fabric. When capturing the boundary of the pattern of the base cloth in an inclined state with respect to the cloth, the subject presser is lowered from the stitch mechanism side to restrict the base cloth in the camera's field of view within the focus range of the camera. I In the meantime, a pattern is imaged by a camera, a circle for detecting a boundary having a radius equal to the stitch width is generated on the pattern image based on the stitch information, and the image is scanned along the circumference of the circle. Detecting the next stitch position from the luminance change amount on the circumference, and the declination between the previous stitch vector and the stitch vector from the current stitch position to the next stitch position candidate on the circumference. Quilting method. 3. A base cloth is fixed on an XY table of an XY guide unit, a pattern of the base cloth is imaged by a camera, and a boundary of the pattern is detected from an image of the base cloth pattern by an image processing unit. After the stitch position is determined above, the control unit that inputs stitch position data drives the XY guide unit to move the XY table so that the stitch position of the base fabric is located below the stitch mechanism needle. After the guidance, the stitch mechanism is operated by the control unit to stitch the stitch position of the base fabric.In the quilting processing apparatus, the camera is arranged beside the stitch mechanism perpendicular to the base fabric, and the camera is mounted on the base fabric. When capturing the boundary of the pattern of the base cloth in an inclined state with respect to the cloth, the subject presser is lowered from the stitch mechanism side to restrict the base cloth in the camera's field of view within the focus range of the camera. I In the meantime, a pattern is imaged by a camera, a circle for detecting a boundary having a radius equal to the stitch width is generated on the pattern image based on the stitch information, and the image is scanned along the circumference of the circle. In the process of detecting the next stitch position from the deviation amount between the luminance change amount on the circumference and the stitch vector from the current stitch position to the next stitch position candidate on the circumference and the previous stitch vector, When the argument is large, the radius of the circle for boundary detection is reduced based on the stitch information, the next stitch position is obtained again, and when the argument for the newly obtained stitch vector becomes small, the circle at that time is obtained. Quilting method, wherein a stitch is performed with a radius of the stitch being a stitch width.