JPH10300424A - Helmet position detecting device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To detect the stepped position of a projection part by irradiating a slit light to the projection part preliminarily provided on a helmet, photographing the irradiated projection part, and arithmetically processing the resulting image signal. SOLUTION: When a laser beam source 1 irradiates a laser beam 9 to a projection part 6 obliquely from 45 under a photographing means 2, a bright line 10 is bent and produced according to the shape of the projection part 6. The periphery of the projection part 6 within a helmet is photographed by the photographing means 2, whereby an image having a bright line 11 can be provided. An analog image signal 13 showing this image 12 is transmitted from the means 2 to an image processing device. When the screen left upper corner is taken as the origin 0 of an XY coordinate system, and the screen horizontal direction and vertical direction are taken as X-axis and Y-axis, respectively, the line 11 of the image 12 is laid along X-direction, but dislocated in Y-direction in the middle in the form corresponding to the sectional form of the projection part 6 to form a stepped part 14. Thus, the X-coordinate value of the stepped part 14 in the image 12 is determined, whereby the position of the projection part 6 of the helmet, or the position of the helmet itself can be judged.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to an apparatus for detecting the position of a helmet by image processing.

[0002]

2. Description of the Related Art In a process of processing a helmet for a factory or a site by a robot, it is necessary to position the helmet. In the past, the helmet was manually positioned.
One example will be described with reference to FIGS.

As shown in FIG. 8, when the helmet 101 is processed, the helmet 101 is placed on a jig 102 upside down. In this case, for positioning, as shown in FIG. 9 as seen from above, a small projection 103 is previously attached to a specific portion of the inner surface of the helmet 101 by a mold at the time of molding. Also, a scribe line 104 is provided in advance on the upper surface of the edge of the jig 102. Then, the worker enters the helmet 101 on the jig 102.
Is turned by hand, and the positions of the protrusion 103 and the scribe line 104 are visually checked to determine the position of the helmet 101 (horizontal rotation angle).
Constant.

The helmet 101 is mainly made of, for example, glass fiber and resin, and is usually formed in a substantially semi-spherical shape.
Examples of the processing of the helmet 101 include a processing of removing the glass fiber 105 protruding from the edge at the time of molding, a processing of attaching parts such as a chin strap, a backing, and ear protection.

However, in manual positioning, it is difficult to automate the processing steps.

If the position of the helmet 101 can be detected by using image processing, automation can be performed. However, at present, there are the following problems. (1) Since the helmet 101 has a semi-spherical shape, it is difficult to measure a specific part by image processing without any attention as it is. (2) Even if a projection is used for measurement in advance during the molding of the helmet 101, it is difficult to measure the projection by ordinary image processing because the projection has the same color as the helmet 101. (3) Since the helmet 101 has a semicircular shape,
Lighting is also a problem. For example, if the lighting is a helmet 101
If this is reflected in the projection, there is a risk that this is erroneously determined as a projection.

[0007]

SUMMARY OF THE INVENTION An object of the present invention is to provide an apparatus capable of detecting the position of a helmet by image processing in view of the above-mentioned problems of the prior art.

[0008]

According to a first aspect of the present invention, there is provided a helmet position detecting apparatus for irradiating a projection provided on a helmet with slit light, and an imaging device for imaging the projection irradiated with the slit light. Means, and an image processing device for calculating an image signal from the imaging means to detect a step position of the protrusion.

According to a second aspect of the present invention, there is provided a helmet position detecting apparatus, wherein a projection attached to the helmet has a band shape, and the light source irradiates the band-shaped projection with two slit lights. There is a feature.

[0010]

Embodiments of the present invention will be described below with reference to the drawings. 1 to 5 show the first embodiment of the present invention.
1 shows an example of a configuration of a helmet position detecting device, FIG. 2 shows an example of a helmet having a projection as a mold, and FIG. 3 shows a positional relationship between the projection of the helmet, a light source, and an imaging unit. 4 shows an example of a captured image, and FIG. 5 shows a measurement principle of image processing. 6 and 7
FIG. 6 shows a configuration example of a helmet position detecting device, and FIG. 7 shows a measurement principle of image processing.

(First Embodiment) A first embodiment of the present invention will be described with reference to FIGS.

The helmet position detecting device exemplified in FIG. 1 mainly includes a laser light source 1, an image pickup means 2, and an image processing device 3, and a horizontal rotation angle of a helmet 5 placed upside down on a jig 4 ( Position). For this reason, a protrusion 6 is formed as a mold at a predetermined specific portion on the inner surface of the helmet 5 when molding the helmet in advance, as illustrated in FIG. The imaging means 2 comprises a camera section 7 such as a CCD camera and a lens section 8. FIG.
Among them, 15 is a personal computer, 16
Is a keyboard, 17 is a monitor (image display device), 18
Indicates a video printer.

The laser light source 1 and the imaging means 2 are used for observing the external shape of an object by a light cutting method. As shown in FIG. 3, the laser light source 1 irradiates a slightly divergent slit light (hereinafter, referred to as laser light) 9 through a narrow slit toward the projection 6 on the inner surface of the helmet 5. The imaging unit 2 captures a bright line 10 generated on the inner surface of the helmet 5 by the irradiation of the laser light 9 obliquely with respect to the optical axis of the laser light 9.

The helmet 5 is usually placed at a substantially fixed position on the jig 4, but in this embodiment, as shown in FIG. Except for the eaves of the helmet 5, the belt-shaped projection 6 is formed from the vicinity of the front end to the top of the center to the rear end. The protruding portion 6 has, for example, a thickness of 1 mm or more in height and a cross-sectional shape of 2 mm or more in width. Further, the laser beam 9 is set to have such a width as to allow the position of the laser beam 9 to sufficiently irradiate the protruding portion 6 while allowing the positional deviation sufficiently. Further, the size of the field of view of the imaging means 2 is set to have a width enough to allow the positional deviation to image the line 10, for example, about 50 mm square on the inner surface of the helmet 5.

In this embodiment, the laser light source 1 emits the laser light 9 in a protruding portion in a state where the width direction of the laser light 9 is parallel to the horizontal plane, and the optical axis is inclined at an angle of 45 degrees from top to bottom with respect to the horizontal. 6 is arranged to irradiate near the rear end. Further, the imaging unit 2 has its optical axis directed vertically downward,
In addition, they are arranged so that the horizontal direction of the visual field is parallel to the horizontal plane (that is, the same as the width direction of the laser light 9).
Therefore, the laser light source 1 irradiates the projection 6 with the laser light 9 from obliquely below the imaging unit 2 by 45 degrees.

When the laser beam 9 strikes the projection 6 on the inner surface of the helmet 5, a bright line 10 is formed by bending according to the shape of the projection 6, as shown in FIG. Therefore, by photographing the vicinity of the protrusion 6 on the inner surface of the helmet 5 by the imaging means 2, an image 12 having a bright line 11 as illustrated in FIG. 4 is obtained. An analog image signal 13 representing the image 12 is sent from the imaging means 2 to the image processing device 3.
In the present invention, the bright line 11 in the image 12 is positively used for detecting the position of the helmet 5.

That is, in FIG. 4, if the upper left corner of the screen is the origin O of the XY coordinate system, the horizontal direction of the screen is the X axis, and the vertical direction of the screen is the Y axis, the line 11 in the image 12 is basically in the X direction. In the Y direction (downward in the Y direction in this example) corresponding to the cross-sectional shape of the projection 6 on the way, and
Occurs. Therefore, if the X coordinate value of the step portion 14 in the image 12 is obtained, the position of the protrusion 6 of the helmet 5, that is, the position of the helmet 5 itself can be determined.

The X-coordinate value of the step portion 14 is where the Y-coordinate value changes greatly in the line 11. The image processing device 3 inputs the analog image signal 13 of the image 12 from the imaging unit 2,
It performs image processing of storing it as digital data and reading out the stored data and performing arithmetic processing.
The position of the helmet 5 is detected by measuring the X coordinate value in which the Y coordinate value greatly changes in the line 11, that is, the step position of the projection 6 irradiated with the laser light 9.

Next, an example of an image processing method in the image processing apparatus 3 for measuring the X coordinate value of the step portion 14 will be described with reference to the following (1) to (9).

(1) First, as shown in FIG.
(For example, if k is the total number of pixels in the X direction, i = 1 to
k, usually for each pixel of the k = 512), to generate a measurement line L _i in the Y direction, measures the Y-coordinate value Y _i of the intersection of the measurement line L _i and the line 11. For example, by extraction from storing the brightest pixel on the measurement line L _i data, measures the Y-coordinate value Y _i.

(2) Then, two measurement lines, for example,
Two adjacent measurement lines L_i-1, L _iOne pair measured by
Y coordinate value of_i-1, Y_iThe difference Y_i-Y_i-1Seeking
Therefore, the set value Y is sequentially calculated as in the following equation_CCompare with

(Y ₂ −Y ₁ )> Y _c (Y ₃ −Y ₂ )> Y _c ··· (Y _i -Y _{i -1} )> Y _c ··· (Y _k −Y _{k -1)} )> _Yc ... Equation 1

(3) From the above comparison, the difference Y _i -Y between a pair of Y coordinate values measured on the two measurement lines L _i-1 and L _i.
i-1 is looking for when it is greater than the set value Y _C, to detect the X-coordinate value X _i of the right measurement line L _i as X on the axis leftmost position candidate of the step portion 14. In addition, since the helmet 5 has a semicircular shape, the line 11 is not strictly a straight line and its Y coordinate value changes even if there is no protrusion 6, but when the protrusion 6 exists, In comparison, since the difference between the Y coordinate values is small and does not change extremely, it is not mistaken for the step portion 14. The set value Y _C is set from such a viewpoint.

(4) Next, in order to avoid a mistake with noise, when a value similar to a certain width is indicated, X _i is determined as the left end position X _CL of the step portion 14 on the X axis. For example, as shown in FIG. 5 (a), Y-coordinate value Y _i-1 of the pair which is measured by the measuring line L _i of two sandwiching measurement line L _i-1, L i _{+ n,} Y _{i + n} difference Y _{i + n} −Y _i-1 and set value Y _C
Compared _{with, Y i + n -Y i-} 1 is greater than Y _C, step is followed by being judged to X on the axis left end position of the stepped portion 14 of the position X _i of the measurement line L _i X _CL Is determined. Y
If _{i + n} -Y _i-1 is less than Y _C, continuing the process (3) determines that the noise. n may be equal to or less than the number of pixels corresponding to the width of the step portion 14. In FIGS. 5A and 5B, n is set to 1 for simplicity.

(5) After the left end position X _CL is determined, a pair of Ys measured on two adjacent measurement lines L _i-1 and L _i.
This time, for each of the coordinate values Y _i−1 and Y _i , Y _i−1 −Y _i is obtained as a difference, and is sequentially compared with the set value Y _C as shown in the following Expression 2.

(Y _i−1 −Y _i )> Y _c (Y _i −Y _{i + 1} )> Y _c (Y _k−1 −Y _k )> Y _c Equation 2

(6) Then, two measurement lines L_i-1,
L_iDifference Y of a pair of Y coordinate values measured in _i-1-Y₁Is set
Value Y_CLook for the case where is larger than the right measurement line L_iof
X coordinate value X_iAs a candidate for the right end position on the X axis of the step portion 14
To detect.

[0026] (7) In order to avoid confusion with this case noise, when pointing to the constant width similar value, to determine the X _i as X on the axis right end position X _CR of the step portion 14. For example, as shown in FIG. 5 (b), 2 pieces of measurement lines sandwiching measurement line _{L i L i-1, L} i a pair measured at _{+ 1} Y
Coordinate values _{Y i-1, Y i +} 1 of the difference Y _i-1 -Y _i + ₁ the set value Y _C
Compared _{with, Y i-1 -Y i +} 1 is larger than Y _C, step is followed by being judged to X on the axis right end position of the stepped portion 14 of the position X _i of the measurement line L _i X _CR Is determined. Y
If _i-1 -Y _i + ₁ is equal to or less than Y _C, continuing the process (6) it is determined that noise.

(8) Further, the left end position X _CL and the right end position X _CR
The average value X _C (= (X _CL + X _CR / 2)) is calculated as the X coordinate value of the step portion 14.

(9) Since the X coordinate value X _C corresponds to the position (horizontal rotation angle) of the helmet 5, the position of the helmet 5 has been detected by calculating X _C. If necessary, the position of the helmet 5 in a desired coordinate system is calculated from the X coordinate value X _C of the step portion 14 by appropriate coordinate conversion.

In FIG. 1, the personal computer 15 and the keyboard 16 control the image processing apparatus 3 or input parameters. The monitor 17 displays images before and after the image processing or the measurement results. Print and output the image before or after image processing.

(Second Embodiment) Next, FIG. 6 and FIG.
Based on the above, a second embodiment of the present invention will be described. FIG.
7 to FIG. 7 relate to a second embodiment of the present invention, FIG. 6 shows a configuration example of a helmet position detecting device, and FIG. 7 shows a measurement principle of image processing.

The helmet position detecting device illustrated in FIG. 6 irradiates two laser beams 9 and 9A onto the elongated belt-like projection 6 of the helmet, so that the laser light source 1 of the helmet position detecting device shown in FIG. And one set of a laser light source 1A and an imaging unit 2A are added to the imaging unit 2. Additional laser light source 1A and imaging means 2A
Has the same configuration as the laser light source 1 and the imaging means 2, but has bright lines 10 generated by the irradiation of the laser lights 9 and 9A.
The position of 10A and the field of view are arranged so as to be shifted in the length direction of the projection 6.

In this embodiment, a bright line 10 generated by irradiation with the laser light 9 of the laser light source 1 is imaged only by the image pickup means 2, and a bright line 10A generated by irradiation by the laser light 9A of the laser light source 1A is formed only by the image pickup means 2A. FIG. 7
(A) As shown in (b), the image 1 of the imaging means 2, 2A
Bright lines 11 and 11A are inserted into 2 and 12A, respectively.

The image processing device 3 receives the analog image signal 13 from the image pickup means 2 and the analog image signal 13A from the image pickup means 2A, converts them into digital data and stores them. By performing the image processing of processing, the XY coordinate value at the place where the Y coordinate value greatly changes in the line 11, that is, the step position of the projection 6 irradiated with the laser light 9 is measured.
The position and the inclination of the helmet 5 are detected by measuring the XY coordinate values where the Y coordinate values greatly change in the line 12A, that is, the step positions of the projections 6 irradiated with the laser light 9A.

An example of an image processing method in the image processing apparatus 3 of this embodiment will be described with reference to the following (1) to (4).

(1) First, as shown in FIG. 7A, the X coordinate value X _C1 of the step portion 14 in the line 11 is obtained as the position of the helmet by the same method as in the first embodiment.
At this time, the Y coordinate value Y _C1 of the step 14 is also obtained. The Y-coordinate value Y _C1, for example, Y-coordinate value Y _{iL 1} line 11 in the measurement line L _i used in the determination of the left end position Y _CL1 on the Y axis
When, using the Y coordinate value Y _iR1 of the line 11 in the measurement line L _i used in the determination of the right end position Y _CR1 on the Y axis, wherein Y _C1
= (Y _iL1 + Y _iR1 ) / 2.

(2) By the same method, as shown in FIG.
Thus, the X coordinate value X of the step 14A in the line 11A_C2And Y
Standard value Y_C2Ask for. This Y coordinate value Y_C2Is the leftmost position on the Y axis
Place Y _CL2Measurement line L used to determine_iLine 11 at
Y coordinate value Y of A_iL2And the right end position Y on the Y axis_CR2Confirmation
Measurement line L used for_iY coordinate value of line 11A at
_iR2And the formula Y_C2= (Y_iL2+ Y_iR2) / 2 operation
Is determined by

(3) Next, the XY coordinate values (X
_C1 , _YC1 ) and the XY coordinate values ( _XC1 ,
Y _C1 ), the inclination θ is obtained by the following equation (3).

Θ = arctan {(Y _C1 −Y _C2 ) / (X _C1 −X _C2 )}

(4) Since the X coordinate value X _C1 corresponds to the position of the helmet (horizontal rotation angle), the position of the helmet 5 is detected. In addition, the inclination θ
Corresponds to the inclination of the helmet, so that the inclination of the helmet is detected by calculating θ. If necessary, the X coordinate value X _C1 and the inclination θ can be obtained by appropriate coordinate conversion.
, The position and inclination of the helmet 5 in the desired coordinate system are calculated.

In the second embodiment, two laser light sources 1 and 1A are used to irradiate two lasers 9 and 9A. However, two slit light beams are radiated by one light source. May be configured. Also. In the second embodiment, the two bright lines 10 and 10A generated on the inner surface of the helmet are separately imaged by the two imaging units 2 and 2A. However, the two bright lines 10 and 10A are generated by one light source. You may comprise so that it may image. In this case, the two bright lines 11 and 11A and the step portions 14 and 14A respectively appear above and below on the same screen, but are divided into two steps and the step portions 1 of the upper and lower lines 11 and 11A are divided.
What is necessary is just to extract and measure 4, 14A. For example, the following methods (1) and (2) are used. (1) For each measurement line, scan from top to bottom to measure two intersections with the two lines, and use only the coordinate values of the upper intersection to extract the step portion of the upper bright line, The step of the lower bright line is extracted using only the coordinate values of the lower intersection, and the position and inclination θ of the helmet 5 are obtained from the obtained XY coordinate values of the upper and lower steps. (2) For each measurement line, for example, scan from top to bottom to measure the intersection with the first line, and extract the step portion of the upper bright line using the coordinate values of the obtained intersection, Next, reversely scan each measurement line from bottom to top to measure the intersection with the first line, and extract the step of the lower bright line using the coordinate values of the obtained intersection. Then, the position and the inclination θ of the helmet 5 are obtained from the obtained XY coordinate values of the upper and lower steps.

[0040]

As described above, according to the first aspect of the present invention, there is provided a light source for irradiating a projection provided on a helmet with slit light, and an imaging means for imaging the projection irradiated with the slit light. By providing an image processing device for calculating the image signal from the imaging means and detecting the step position of the protrusion, the position of the helmet can be detected by the image processing method, and the following effects are obtained. . (1) The helmet processing process can be automated. (2) It can support helmets of all colors such as white, yellow, green, red, and blue.

According to the second aspect of the present invention, the shape of the projection attached to the helmet is band-shaped, and by irradiating the slit-shaped projection with two slit lights, the position of the helmet can be increased. , Inclination can be detected.

[Brief description of the drawings]

FIG. 1 is a diagram showing a configuration of a helmet position detecting device according to a first embodiment of the present invention.

FIG. 2 is a perspective view of a helmet having a projection as a mold.

FIG. 3 is a diagram illustrating an example of a positional relationship among a protrusion of a helmet, a light source, and an imaging unit.

FIG. 4 is a diagram showing an example of a captured image.

FIG. 5 is a diagram showing a measurement principle of image processing.

FIG. 6 is a diagram showing a configuration of a helmet position detecting device according to a second embodiment of the present invention.

FIG. 7 is a diagram showing a measurement principle of image processing.

FIG. 8 is a side view of a helmet and a jig showing positioning by a conventional manual operation.

FIG. 9 is a plan view of a helmet and a jig showing positioning by a conventional manual operation.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1, 1A Laser light source 2, 2A Imaging means 3 Image processing device 4 Jig 5 Helmet 6 Projection part 7 Camera part 8 Lens part 9, 9A Laser light (slit light) 10, 10A Bright line generated on inner surface of helmet 11, 11A Bright line in image 12, 12A Image 13, 13A Analog image signal 14, 14A Step

Claims (2)

[Claims] 1. A light source for irradiating a projection on a helmet with slit light, an imaging unit for capturing an image of the projection irradiated with the slit light, and an image signal from the imaging unit being arithmetically processed to generate the projection. A helmet position detecting device comprising an image processing device for detecting the position of the helmet. 2. The helmet according to claim 2, wherein the helmet has a strip-shaped projection, and the light source irradiates the strip-shaped projection with two slit lights. Helmet position detection device.