JPH102726A - Measuring plate and device and method for measuring wheel alignment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the measuring accuracy, the reliability and the reproducibility of alignment by drawing a plurality of concentric circles, with a specified original points position as a center, and attaching the concentric circles and gridlike graduation lines, so that the position of the original point agrees with the center of the rotary shaft of the wheel of a vehicle under inspection. SOLUTION: A CCD camera 5, which can pick up a color image, picks up the image of a test surface 4S of a measuring plate 4, which is attached to a tire wheel 3 of a vehicle to be measured 2 and measures the distance to the measurement surface 4S by a laser projector 6 at the same time. Alignment operation is performed by a data processing unit 8. Then, concentric circles C1-C3, wherein the positions of the specified original points are the centers, and grid-shaped graduation lines LX1-LX7 and LZ1-LZ7 are drawn and attached, so that the position O of the original point agrees with the center of the rotary shaft of the wheel of the vehicle under inspection. By picking up the image of the measuring plate 4, the concentric circle is specified by the curvature of the concentric circle, and the symmetrical position of the measurement is computed corresponding to the rotary shaft of the wheel.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a measuring plate, a wheel alignment measuring device and a wheel alignment measuring method, and more particularly to a vehicle basic characteristic measuring device for three-dimensionally measuring a displacement and an angle of a tire wheel when a vehicle is driven. The present invention relates to a measurement plate, a wheel alignment measurement device, and a wheel alignment measurement method used for wheel alignment measurement.

[0002]

2. Description of the Related Art A vehicle basic characteristic measuring device is known as a test device for measuring basic characteristics of a vehicle such as a suspension characteristic and a steering characteristic of a vehicle in a test room.
In the vehicle basic characteristic measuring device, a test vehicle is fixed at a predetermined position, a force such as rotation, left, right, up, down, front and back is applied to a tire wheel, and a measurement obtained in consideration of a reaction force generated at that time. By processing the data, it is possible to measure various vehicle basic characteristics.

[0003] As a part of the vehicle basic characteristic measuring device, a wheel alignment measuring device for measuring a wheel alignment such as a caster angle, a camber angle and a toe angle based on a distance from a reference position to a tire wheel side surface. There is. Conventional wheel alignment measuring devices generally support a tire wheel and are fixed on a platform driven by an actuator, and are connected to the tire wheel to mechanically detect the movement of the tire wheel. . This type of mechanical wheel alignment measurement device has a problem that high-speed measurement cannot be performed due to a reduction in measurement accuracy due to friction of a movable portion and restrictions due to inertial mass of components and the like.

In order to solve this problem, a non-contact wheel alignment measuring apparatus using a non-contact distance sensor such as a laser beam sensor or an ultrasonic sensor has been proposed. More specifically, the conventional ultrasonic wheel alignment measuring device arranges a plurality of ultrasonic sensors at predetermined positions on the side of the tire wheel, and a measurement plate attached to the side of the tire wheel from a predetermined machine gun position. Is measured by ultrasonic waves, and the camber angle and the toe angle are obtained based on the obtained measurement data (for details, see Japanese Utility Model Application Laid-Open No. 63-44107).
Reference).

In a conventional optical wheel alignment measuring device, a measuring unit having a plurality of optical sensors (for example, a laser beam sensor) is installed on a platform on a side of a tire wheel, and the measuring unit is positioned in front and rear of a vehicle. In the direction, and optically measures the distance from a predetermined reference position to a measurement plate attached to the side surface of the tire wheel, and obtains a camber angle and a toe angle based on the obtained measurement data. (For details, refer to JP-A-63-94103).

[0006]

The above-mentioned conventional ultrasonic wheel alignment measuring apparatus can measure a large displacement, but it does not allow the inclination of the sensor axis of the ultrasonic sensor with respect to the test surface of the measuring plate. The range is about ± 7 [゜] at maximum due to the limitation of the reflection angle, and the inclination of the sensor axis of the ultrasonic sensor with respect to the test surface of the measurement plate is ± 45.
There is a problem that it cannot be used for measurement with a wide inclination range, such as measurement of wheel alignment including the steering system, which is described as [゜].

In the optical wheel alignment measuring device using the above-mentioned conventional laser beam sensor, the measurable displacement range (measurable distance range) centered on the reference distance between the test surface of the measuring plate and the laser beam sensor is set. It is difficult to make the maximum value ± 100 [mm] or more from the viewpoint of accuracy and cost. For this reason, in an actual device, an optical wheel alignment measuring device is fixed on a platform so that measurement can be performed even with a laser beam sensor having a small measurable displacement range.

In this case, what is actually to be measured is the alignment of the wheel with respect to the vehicle body. By the way, since the vehicle body is fixed at a predetermined reference position, the relative positional relationship between the platform and the wheel alignment measuring device changes even if the platform is displaced with respect to this reference position due to the driving of the actuator. Instead, the wheel alignment measurement data will include the amount of platform displacement.

However, since the amount of displacement of the platform cannot be separated from the measured data, the measured data includes a measurement error, and there is a problem that an accurate wheel alignment measurement cannot be performed. Although it is conceivable to perform data correction to remove this measurement error, the measurement conditions are various, so that correction cannot be performed reliably, and there is a problem that measurement accuracy, reliability and reproducibility are lacking. .

An object of the present invention is to reliably and quickly grasp the relative positional relationship between a measurement plate and a wheel alignment measuring device, and to improve the measurement accuracy, reliability and reproducibility of alignment. An object of the present invention is to provide a measurement plate, a wheel alignment measuring device, and a wheel alignment measuring method that can be performed.

[0011]

According to a first aspect of the present invention, a plurality of concentric circles and a grid-like graduation line centered on a predetermined origin position are drawn on a test surface. The inspection vehicle is mounted so that the origin position coincides with the center of the rotation axis of the wheel of the inspection vehicle.

According to the first aspect of the present invention, a plurality of concentric circles and a grid-like graduation line centered on a predetermined origin position are drawn on the test surface, and the plurality of concentric circles and the grid lines are placed on the center of the rotation axis of the wheel of the vehicle to be inspected. Since it is attached so that the origin position coincides, based on the curvature of the concentric circle imaged by imaging the measurement plate, the concentric circle is specified, and the measurement target position is determined from the positional relationship between the concentric circle and the scale line by the specified concentric circle. It can be calculated in association with the rotation axis of the wheel.

According to a second aspect of the present invention, in the first aspect of the invention, the scale lines are a plurality of first scale lines parallel to each other, and a plurality of first scale lines intersecting the first scale lines and parallel to each other. A second graduation line, the concentric circle, the first
The graduation line and the second graduation line are configured to be drawn in different colors.

According to the second aspect of the present invention, in addition to the operation of the first aspect, the concentric circle, the first scale line, and the second scale line are drawn in different colors from each other. Each can be easily distinguished clearly. According to a third aspect of the present invention, in the second aspect, the concentric circle, the first graduation line, or the second graduation line is drawn in any one of red, green, and blue.

According to the third aspect of the invention, in addition to the operation of the second aspect, the concentric circle, the first graduation line or the second graduation line is drawn in any one of red, green and blue. Therefore, by performing the color separation process using the three primary colors of light, it is possible to easily and quickly distinguish each other.

According to a fourth aspect of the present invention, there is provided a wheel alignment measuring apparatus for measuring wheel alignment using the measuring plate according to any one of the first to third aspects, wherein at least one of the plurality of concentric circles is provided. Imaging means for imaging the test surface such that at least a part of any one of the concentric circles and at least a part of the scale line are included in the imaging screen, and which is included in the imaging screen of the imaging means A discriminating means for discriminating which of the concentric circles is based on the curvature of the concentric circle in the imaging screen; and a scale line specifying means for specifying the scale line included in the imaging screen based on the discrimination result of the discriminating means. And the measurement plate corresponding to the measurement target position based on the positional relationship between the specified scale line and the measurement target position in the imaging screen of the imaging unit. Configure and a calculating means for calculating the position.

According to the fourth aspect of the present invention, the image pickup means includes at least a part of at least one of the plurality of concentric circles drawn on the measurement plate and at least a part of the scale line in the image pickup screen. The test surface is imaged so as to be included in. The determination means determines which of the concentric circles is included in the imaging screen of the imaging means based on the curvature of the concentric circle in the imaging screen.

The scale line specifying means specifies a scale line included in the imaged screen based on the result of the determination by the determining means. As a result, the calculation means calculates a position on the measurement plate corresponding to the measurement target position based on the positional relationship between the specified scale line and the measurement target position in the imaging screen of the imaging means.

According to a fifth aspect of the present invention, in the fourth aspect of the present invention, the determination means includes a storage means for storing in advance the curvatures of the plurality of concentric circles, and the imaging means based on an output signal of the imaging means. Concentric circle extracting means for extracting concentric circles included in the screen, curvature calculating means for calculating the curvature of the extracted concentric circles, and comparing the curvature calculated by the curvature calculating means with the curvature stored in the storage means. Concentric circle specifying means for specifying a concentric circle having the curvature.

According to the fifth aspect of the present invention, in addition to the operation of the fourth aspect of the present invention, the storage means of the determining means stores the curvatures of a plurality of concentric circles in advance. The concentric circle extraction unit extracts a concentric circle included in the imaged screen based on the curvature stored in the storage unit and the output signal of the imaging unit.

The curvature calculation means calculates the curvature of the extracted concentric circle, and the concentric circle specification means specifies the concentric circle having the curvature by comparing the curvature calculated by the curvature calculation means with the curvature stored in the storage means. An invention according to claim 6 is a wheel alignment measuring device that measures wheel alignment using the measurement plate according to claim 2 or 3, wherein at least one of the plurality of concentric circles is at least one of the plurality of concentric circles. Imaging means for imaging the test surface and outputting imaging data so that a part and at least a part of the scale line are included in the imaging screen,
A color separation unit that performs color separation of the imaging data and outputs color separation imaging data, and is included in the imaging screen of the imaging unit based on the color separation imaging data and a curvature of a concentric circle in the imaging screen. Is a discriminating means for discriminating which of the concentric circles, a scale line specifying means for specifying the scale lines included in the imaging screen based on the discrimination result of the discriminating means and the color separation image data, Calculating means for calculating a position on the measurement plate corresponding to the measurement target position based on a positional relationship between the specified scale line and the measurement target position in the imaging screen of the imaging means.

According to the sixth aspect of the present invention, the imaging means performs the test so that at least a part of at least one of the plurality of concentric circles and at least a part of the graduation line are included in the imaging screen. The surface is imaged and the imaged data is output to the color separation means. The color separation unit performs color separation of the image data and outputs the color separation image data to the determination unit.

The determining means determines which of the concentric circles is included in the imaging screen of the imaging means based on the color separation imaging data and the curvature of the concentric circles in the imaging screen, and specifies the scale line. The means specifies a scale line included in the imaging screen based on the result of the determination by the determination means and the color separation image data.

As a result, the calculation means calculates a position on the measurement plate corresponding to the measurement target position based on the positional relationship between the specified graduation line and the measurement target position in the imaging screen of the imaging means. According to a seventh aspect of the present invention, in the invention of the sixth aspect, the determination unit is included in the imaging screen based on the color separation imaging data based on the storage unit that stores the curvatures of the plurality of concentric circles in advance. Concentric circle extracting means for extracting the concentric circles to be extracted, a curvature calculating means for calculating the curvature of the extracted concentric circles, and having the curvature by comparing the curvature calculated by the curvature calculating means with the curvature stored in the storage means. Concentric circle specifying means for specifying a concentric circle.

According to the seventh aspect of the present invention, in addition to the operation of the sixth aspect, the storage means of the determination means stores the curvatures of a plurality of concentric circles in advance. Concurrently, the concentric circle extracting means extracts the concentric circles included in the imaging screen based on the color separation imaging data, and the curvature calculating means calculates the curvature of the extracted concentric circles. Thereby, the concentric circle specifying means specifies the concentric circle having the curvature by comparing the curvature calculated by the curvature calculating means with the curvature stored in the storage means.

According to an eighth aspect of the present invention, in the invention according to any one of the fourth to seventh aspects, the spin angle is calculated by calculating an inclination of the graduation line in the imaging screen with respect to a predetermined reference position. It comprises a spin angle calculating means for calculating. According to a ninth aspect of the present invention, there is provided a wheel alignment measuring method for measuring a wheel alignment using the measuring plate according to any one of the first to third aspects, wherein at least one of the plurality of concentric circles is used. An imaging step of imaging the test surface so that at least a part of the concentric circles and at least a part of the scale line are included in the imaging screen, and which concentric circles are included in the imaging screen. A determining step of determining based on the curvature of concentric circles in the imaging screen, a scale line specifying step of specifying the scale lines included in the imaging screen based on the result of the determination, and the specified scale line and Calculating a position on the measurement plate corresponding to the measurement target position based on a positional relationship with the measurement target position in the imaging screen. .

According to the ninth aspect of the present invention, in the imaging step, the test is performed so that at least a part of at least one of the plurality of concentric circles and at least a part of the graduation line are included in the image plane. Image the surface. The determining step determines which of the concentric circles is included in the imaging screen based on the curvature of the concentric circle in the imaging screen.

In the scale line specifying step, a scale line included in the imaged image is specified based on the result of the discrimination in the discriminating step. The calculation step calculates a position on the measurement plate corresponding to the measurement target position based on the positional relationship between the specified scale line and the measurement target position in the imaging screen.

According to a tenth aspect of the present invention, in the ninth aspect of the present invention, the discriminating step includes a concentric circle extracting step of extracting a concentric circle included in the imaging screen based on the imaging data. A curvature calculating step of calculating a curvature of the concentric circle; and a concentric specifying step of specifying a concentric circle having the curvature by comparing the curvature calculated by the curvature calculating means with a curvature stored in advance.

According to the tenth aspect, the ninth aspect is provided.
In addition to the operation of the described invention, the concentric circle extracting step of the discriminating step extracts concentric circles included in the imaged screen based on the imaged data. The curvature calculation step calculates the curvature of the extracted concentric circle.

The concentric circle specifying step specifies a concentric circle having the curvature by comparing the curvature calculated by the curvature calculating means with the curvature stored in the storage means. According to an eleventh aspect of the present invention, there is provided a wheel alignment measuring method for measuring wheel alignment using the measuring plate according to the second or third aspect, wherein at least one of the plurality of concentric circles is at least one of the plurality of concentric circles. An imaging step of imaging the test surface so as to include a part and at least a part of the scale line in an imaging screen to generate imaging data; and performing color separation of the imaging data to generate color separation imaging data. A color separation step, a determination step of determining which concentric circle is included in the imaging screen of the imaging unit based on the color separation imaging data and the curvature of a concentric circle in the imaging screen; A scale line specifying step of specifying the scale line included in the imaging screen based on the result of the determination and the color separation image data; and the specified scale line Based on the positional relationship between the measured position of the imaging screen of the imaging means, configured to include a calculation step of calculating a position on the measuring plate corresponding to the measuring points.

According to the eleventh aspect, in the imaging step, the test is performed such that at least a part of at least one of the plurality of concentric circles and at least a part of the graduation line are included in the imaging screen. The surface is imaged to generate imaging data. In the color separation step, color separation of the imaging data is performed to generate color separation imaging data.

The discriminating step and discriminating which of the concentric circles is included in the imaging screen of the imaging means based on the color separation imaging data and the curvature of the concentric circles in the imaging screen. The scale line specifying step specifies a scale line included in the imaging screen based on the determination result and the color separation imaging data.

In the calculating step, a position on the measurement plate corresponding to the measurement target position is calculated based on the positional relationship between the specified scale line and the measurement target position in the imaging screen of the imaging means. The twelfth aspect of the present invention provides the ninth to eleventh aspects.
The invention according to any one of the above, further comprising a spin angle calculation step of calculating a spin angle by calculating an inclination of the graduation line in the imaging screen with respect to a predetermined reference position.

According to the eighth aspect of the present invention, in addition to the operation of the fourth aspect of the present invention, the spin angle calculating means may be arranged such that the spin angle calculating means is provided with respect to the predetermined reference position of the graduation line in the imaging screen. The spin angle is calculated by calculating the inclination. According to the twelfth aspect of the present invention, in addition to the operation of the ninth to eleventh aspects, in the spin angle calculating step, the inclination of the graduation line in the imaging screen with respect to the predetermined reference position is calculated. By doing so, the spin angle is calculated.

[0036]

Preferred embodiments of the present invention will now be described with reference to the drawings. Schematic Configuration of Alignment Measuring Device FIG. 1 shows a schematic configuration block diagram of a wheel alignment measuring device.

The wheel alignment measuring device 1 is roughly divided into a measuring plate 4 attached to a tire wheel 3 of a measuring vehicle 2 and a CCD camera 5 capable of color imaging, and images the test surface 4S of the measuring plate 4 Measurement unit 7 for measuring the distance to the test surface 4S of the measurement plate by a plurality of laser projectors 6
And a data processing unit 8 for performing an alignment operation based on the output signal of the measurement unit 7.

The data processing unit 8 includes the measuring unit 7
Processor 8 that performs various calculations based on the output signal of
A, a display 8B for displaying various information under the control of the processor 8A, a keyboard 8C for inputting various data to the processor 8A, and printing of various data under the control of the processor 8A. Out printer 8D. Configuration Figure 2 of the measuring plate shows a front view of the measuring plate.

On the test surface 4S of the measuring plate 4, the base portion is colored black, and three concentric circles C1 to C3 centered on the origin O are drawn in green, and the concentric circles C1 to C3 are drawn. Is set to, for example, C1: C2: C3 = 1: 2: 3. The radius ratio of the concentric circles C1 to C3 is not limited to this, but may be set as long as each concentric circle can be discriminated (discriminated) by image processing based on curvature or the like.

The scale lines LX1 to LX7 parallel to the X axis
Are drawn in red so as to contact the corresponding concentric circles C1 to C3. Furthermore, the scale lines LZ1 to LZ7 parallel to the Z axis
Are drawn in blue so as to contact corresponding concentric circles C1 to C3.

In this embodiment, the scale lines LX1 to LX1
X7 and the scale lines LZ1 to LZ7 are perpendicular to each other and are tangents to the concentric circles C1 to C3. However, the present invention is not limited to this, and the arithmetic processing becomes complicated, but is drawn at predetermined intervals so as to intersect at a predetermined angle. If it is, the same effect can be obtained.

[0042] shows a perspective view of the measuring unit in diagram 3 of the measuring unit. The measurement unit 7 has a substantially rhombus-shaped holding plate 10 for holding the four laser projectors 6 and a holding plate 10 for imaging the measurement plate 4 through an opening 10A provided at the center of the holding plate 10. It has a CCD camera 5 provided on the back side and a Z-axis direction drive knob 11, and the operator rotates the Z-axis direction drive knob 11 to drive the holding plate 10 and the CCD camera 5 in the Z-axis direction. It has a Z-axis direction drive unit 12 and an angle direction drive knob 13, and the operator rotates the angle direction drive knob 13 to rotate the holding plate 10 and the CCD camera 5 in the direction of arrow A in FIG. An angle direction drive unit 14 and a Y axis direction drive knob 15 are provided, and the holding plate is rotated by turning the Y axis direction drive knob 15 by an operator. 0 and a Y-axis direction driving unit 16 for driving the CCD camera 5 in the Y-axis direction, and an X-axis direction driving knob 17. The operator rotates the X-axis direction driving knob 17 to rotate the holding plate 10 and the holding plate 10. An X-axis direction drive unit 18 for driving the CCD camera 5 in the X-axis direction, a holding plate 10, the CCD camera 5, a Z-axis direction drive unit 12,
Y axis direction drive unit 14 and X axis direction drive unit 1
Base unit 19 for holding base unit 8 and base unit 1
Guide rail 20 for sliding 9 in the X-axis direction
And is provided. Shows a schematic configuration block diagram of a processor body of the data processing unit to the structure 4 of the processor body.

The processor main body 8A is provided with the processor main body 8A.
A controller 25 for controlling the entire A, and controller 2
5, an interface unit 26 for performing an interface operation between the display 8B, the keyboard 8C and the printer 8D, and a color separation process based on the imaging data DCCD output from the CCD camera 5 to obtain red imaging data corresponding to red. DR, a color separation processing circuit 27 that outputs green imaging data DG corresponding to green and blue imaging data DB corresponding to blue, and four laser projectors 6
Output signals DLD1 to DLD4 and red image data D
R, X coordinate data DX, Z coordinate on the test surface 4S of the measurement plate 4 at a predetermined position (for example, the center point of the imaging screen) in the imaging screen of the CCD camera 5 based on the green imaging data DG and the blue imaging data DB. An arithmetic processing unit 28 which calculates and outputs the data DZ and the inclination (spin angle) data DSP of the X axis (or Z axis) with respect to the reference direction.
And is provided. Measurement Operation Next, the measurement operation will be described with reference to FIGS.

In this case, the imaging screen of the CCD camera 5 is set so as to include at least one concentric circle and at least one graduation line regardless of which of the test surfaces 4S of the measurement plate 4 is imaged. It is assumed that the measurement plate 4 is mounted in advance in the tire hole 3 of the measurement vehicle 2 such that the origin O of the test surface 4S coincides with the rotation center axis of the tire wheel 3.

FIG. 5 shows a flowchart of the measuring operation process. First, the operator slides the base unit 19 on the guide rail 20 in the X-axis direction,
Axial drive unit 12 (operates Z-axis drive knob 11), angle-direction drive unit 14 (operates angle-direction drive knob 13), Y-axis drive unit 16 (operates Y-axis drive knob 15), or X-direction Drive unit 1
8 (by operating the X-axis direction drive knob 17), the holding plate 10 and the CCD camera 5 are opposed to the test surface 4S of the measurement plate 4, and the center point CC (see FIG. (See S1) with the origin O of the test surface 4S (step S1).

Next, the tire wheels 3 of the measuring vehicle 2 are independently driven upward or downward for each tire wheel by an actuator (not shown). Then, the actuator is stopped, and the state at the time of stop is maintained (Step S
2). Here, the calculation of the coordinates of the center point CC of the imaging screen FL according to the imaging state will be described in different cases. A: One concentric circle and two scale lines are included in the imaging screen
If Figure 6 is in the imaging screen showing the image pickup plane of the CCD camera 5 when it contains one concentric and two gridlines.

Next, the processor body 8A of the data processing unit 8 controls the CCD camera 5 of the measuring unit 7 to image the test surface 4S (step S3), and converts the image data DCCD into the color separation processing circuit of the processor body 8A. 27 (step S4). Under the control of the controller 25, the color separation processing circuit 27 performs color separation processing on the image data DCCD output from the CCD camera 5, and obtains red image data DR corresponding to red and green image data DG corresponding to green. And blue imaging data DB corresponding to blue
Is output to the arithmetic processing unit 28 (step S5).

In parallel with the image pickup processing of the CCD camera 5, the four laser projectors 6 irradiate the test surface 4S of the measurement plate 4 with laser light, and output signals DLD1 to DLD1 to DLD1 to corresponding to the distance between the measurement plates 4. DLD4 to arithmetic processing unit 2
8 (step S6).

The arithmetic processing section 28 first extracts a concentric circle CXX (= one of the concentric circles C1 to C3) in the imaging screen FL based on the green imaging data DG, and outputs an output signal DLD.
1 to DLD4 to perform concentric circle CXX
Is determined (step S7), and by comparing with the curvatures of a plurality of concentric circles stored in advance, it is determined which of the concentric circles CXX is (step S8).

In the following description, the determined concentric circle C
Description will be made assuming that the radius of XX = R. Next, the arithmetic processing unit 28 determines the position of the scale line included in the imaging screen based on each of the red imaging data DR and the blue imaging data DB (Step S9).

With respect to the graduation line determined in the process of step S, a perpendicular line is lowered from the center point CC of the imaging screen, and the distances ΔX and X from the center point CC to the graduation line parallel to the Z axis are set.
The distance ΔZ between the scale lines parallel to the axis is calculated (step S10). In this case, when the perpendicular intersects (including tangent) the concentric circle CXX when the perpendicular is lowered from the center point CC to the scale line, the scale line is concentric C
It can be determined that the scale line circumscribes XX.
When the perpendicular does not intersect with the concentric circle CXX,
The scale line can be determined to be either a scale line circumscribing the concentric circle having the largest radius or a scale line passing through the origin O among concentric circles having a radius smaller than the concentric circle CXX.

If the vertical line cannot be lowered in the imaging screen FL, the vertical line is lowered on a straight line obtained by extending the scale line on the virtual screen, and the distance to the scale line is obtained. Then, the arithmetic processing unit 28 calculates the obtained distance ΔX,
The coordinates (XC, ZC) of the center point CC of the imaging screen FL are obtained based on ΔZ and the coordinates of the scale line (step S11). Note that the distance Δ
Whether to add or subtract X and ΔZ depends on the quadrant where the center point CC is located. Therefore, the quadrant where the center point CC is located is accurately determined based on the convex direction of the circumference of the concentric circle and the extending direction of the scale line. Must be determined.

More specifically, in the case of FIG. 6, (XC, ZC) = (R−ΔX, R−ΔZ). Next, the arithmetic processing unit 28 obtains the spin angle by calculating the inclination between the horizontal direction (or the vertical direction) of the imaging screen and the scale line (step S12).

As a result, the arithmetic processing unit 28 outputs the obtained center coordinate XC as X coordinate data DX, outputs the obtained center coordinate ZX as Z coordinate data DZ, and uses the obtained spin angle as inclination data DSP. Will be output. B: One concentric circle and one graduation line are included in the imaging screen
When Figure 7 is in the imaging screen of the CCD camera 5 one concentric and 1
13 shows an imaging screen when a book scale line is included.

Next, the processor body 8A of the data processing unit 8 controls the CCD camera 5 of the measurement unit 7 to image the test surface 4S (step S3), and converts the image data DCCD into a color separation processing circuit of the processor body 8A. 27 (step S4). Under the control of the controller 25, the color separation processing circuit 27 performs color separation processing on the image data DCCD output from the CCD camera 5, and obtains red image data DR corresponding to red and green image data DG corresponding to green. And blue imaging data DB corresponding to blue
Is output to the arithmetic processing unit 28 (step S5).

In parallel with the image pickup processing of the CCD camera 5, the four laser projectors 6 irradiate the test surface 4S of the measurement plate 4 with laser light, and output signals DLD1 to DLD1 to DLD1 to corresponding to the distance between the measurement plates 4. DLD4 to arithmetic processing unit 2
8 (step S6).

The arithmetic processing unit 28 first extracts a concentric circle CXX (= one of the concentric circles C1 to C3) in the imaging screen FL based on the green imaging data DG, and outputs an output signal DLD.
1 to DLD4 to perform concentric circle CXX
Is determined (step S7), and by comparing with the curvatures of a plurality of concentric circles stored in advance, it is determined which of the concentric circles CXX is (step S8).

In the following description, the determined concentric circle C
Description will be made assuming that the radius of XX = R. Next, the arithmetic processing unit 28 determines the position of the scale line included in the imaging screen based on each of the red imaging data DR and the blue imaging data DB (Step S9).

With respect to the scale line parallel to the Z axis determined in the processing of step S9, a perpendicular line is lowered from the center point CC of the image pickup screen, and the scale line LZX parallel to the Z axis from the center point CC.
Then, a distance ΔX1 is calculated (step S10). In this case, when the perpendicular intersects (including tangent) the concentric circle CXX when the perpendicular is lowered from the center point CC to the scale line, it is determined that the scale line is a scale line circumscribing the concentric circle CXX. can do. When the perpendicular does not intersect with the concentric circle CXX, the graduation line is a graduation line circumscribing the concentric circle having the largest radius or the graduation line passing through the origin O among the concentric circles having a smaller radius than the concentric circle CXX. It can be determined that it is either.

If the vertical line cannot be lowered in the imaging screen FL, the vertical line is lowered on a straight line obtained by extending the scale line on the virtual screen, and the distance to the scale line is obtained. Then, the arithmetic processing unit 28 calculates the distance ΔX1
Then, based on the coordinates of the scale line LZX, the coordinates (XC, ZC) of the center point CC of the imaging screen FL are obtained (step S11).

More specifically, the arithmetic processing unit 28 lowers a perpendicular line from the center point CC of the imaging screen FL to the scale line LZX, sets the intersection point to P1, and sets the distance from the center point CC to the intersection point P1 to ΔX1. I do. Next, the arithmetic processing unit 28 lowers the perpendicular to the concentric circle CXX, extends the perpendicular to the scale line LZX, and sets the intersection point to P2. When this perpendicular line extends in the opposite direction to the scale line LZX,
It will pass through the origin O.

As a result, the triangle specified by the three points CC, P1, and P2 and the triangle specified by the three points O, PLZX, and P2 have similar shapes. Therefore, the distance from the intersection P1 to the intersection P2 is Z1, the distance from intersection P2 to point PLZX is Z
Assuming that Z, the relationship of R: ΔX1 = ZZ: Z1 is satisfied, and ZZ = (R · Z1) / ΔX1. Therefore, (XC, ZC) = (R−ΔX1, ZZ−Z1) = (R−ΔX1, (R · Z1) / ΔX1−Z1) = (R−ΔX1, {[R / ΔX1] −1} · Z1 ).

Next, the arithmetic processing section 28 obtains the spin angle by calculating the inclination between the horizontal direction (or the vertical direction) of the image screen and the graduation line (step S12).
As a result, the arithmetic processing unit 28 determines the calculated center coordinate XC
Is output as X coordinate data DX, and the obtained center coordinate ZX
Is output as the Z coordinate data DZ, and the obtained spin angle is output as the inclination data DSP. As described above, according to the present embodiment, the measurement of the predetermined position (the center point in the above description) in the imaging screen based on the imaging screen including at least a part of the concentric circle and at least one graduation line. The position corresponding to the origin on the test surface 4S of the plate 4 can be calculated quickly and accurately, and the reproducibility of the measurement is improved.

Accordingly, the wheel alignment measurement can be performed quickly and accurately, and the reproducibility and reliability thereof can be improved.

[0065]

According to the first aspect of the present invention, a plurality of concentric circles and a grid-like graduation line centered on a predetermined origin position are drawn on the test surface, and the center of the rotation axis of the wheel of the vehicle to be inspected. Is attached so that the origin position coincides with the measurement target plate. The position can be calculated quickly and accurately in association with the rotation axis of the wheel, and the wheel alignment measurement can be performed quickly and accurately, so that reproducibility and reliability can be improved.

According to the second aspect of the invention, in addition to the operation of the first aspect, the concentric circle, the first scale line, and the second scale line are drawn in different colors from each other. Each of them can be easily distinguished clearly, and the position to be measured can be accurately grasped.

According to the third aspect of the invention, in addition to the operation of the second aspect, the concentric circle, the first scale line or the second scale line is drawn in any one of red, green and blue. Therefore, by performing color separation processing with the three primary colors of light, it is possible to easily and quickly distinguish each other by performing image processing, and it is possible to perform quick and accurate position measurement, and thus In addition, accurate wheel alignment measurement can be performed.

According to the fourth aspect of the present invention, the image pickup means includes at least a part of at least any one of a plurality of concentric circles drawn on the measurement plate and at least a part of the graduation lines in the image pickup screen. The determination unit determines which concentric circle is included in the imaging screen of the imaging unit based on the curvature of the concentric circle in the imaging screen, and includes a scale. The line identifying means is
A scale line included in the imaging screen is specified based on the determination result of the determination unit, and the calculation unit is configured based on a positional relationship between the specified scale line and a measurement target position in the imaging screen of the imaging unit.
Since the position on the measurement plate corresponding to the position to be measured is calculated, the position of the measurement plate corresponding to the position to be measured can be accurately calculated.
Highly reliable wheel alignment measurement can be performed.

According to the fifth aspect of the present invention, in addition to the operation of the fourth aspect, the storage means of the discriminating means stores the curvatures of a plurality of concentric circles in advance, and the concentric circle extracting means stores the stored concentric circles. Based on the curvature and the output signal of the imaging unit, a concentric circle included in the imaging screen is extracted, the curvature calculating unit calculates the curvature of the extracted concentric circle, and the concentric circle specifying unit calculates the curvature calculated by the curvature calculating unit. Since the concentric circle having the curvature is specified by comparing the curvature with the curvature stored in the storage means, the concentric circle can be reliably and accurately specified, and the measurement target position can be accurately measured.

According to the sixth aspect of the present invention, the image pickup means performs the test so that at least a part of at least one of the plurality of concentric circles and at least a part of the graduation line are included in the image pickup screen. An image of the surface, and output imaging data to a color separation unit. The color separation unit performs color separation of the imaging data and outputs the color separation imaging data to a determination unit. Based on the curvature of the concentric circles in the middle, it is determined which of the concentric circles is included in the imaging screen of the imaging means, and the scale line specifying means is based on the determination result of the determination means and the color separation image data. The calculation means specifies the graduation line included in the imaging screen, and based on the positional relationship between the specified graduation line and the measurement target position in the imaging screen of the imaging means, the calculation means Rank , The position of the measurement plate corresponding to the position to be measured can be accurately and quickly calculated, and as a result, accurate, reproducible, and highly reliable wheel alignment measurement can be performed. .

According to the seventh aspect of the present invention, in addition to the operation of the sixth aspect, the storage means of the discriminating means stores the curvatures of a plurality of concentric circles in advance, and the concentric circle extracting means stores the color separation image. Based on the data, concentric circles included in the imaging screen are extracted, the curvature calculating means calculates the curvature of the extracted concentric circles, and the concentric circle specifying means calculates the curvature calculated by the curvature calculating means in the storage means. Since the concentric circle having the curvature is specified by the comparison, the concentric circle required for the measurement can be specified reliably and quickly.

According to an eighth aspect of the present invention, in addition to the operation of the fourth aspect of the present invention, the spin angle calculation means is provided for the scale line in the image pickup screen with respect to a predetermined reference position. Since the spin angle is calculated by calculating the inclination, the spin angle can be calculated quickly and accurately.

According to the ninth aspect of the present invention, in the imaging step, the test is performed such that at least a part of at least one of the plurality of concentric circles and at least a part of the graduation line are included in the imaging screen. The surface is imaged, and the discrimination process includes
Which concentric circles are included in the imaging screen is determined based on the curvature of the concentric circles in the imaging screen,
The scale line specifying step specifies a scale line included in the imaging screen based on the result of the determination in the determination step, and the calculation step performs based on a positional relationship between the specified scale line and a measurement target position in the imaging screen. Since the position on the measurement plate corresponding to the position to be measured is calculated, the position on the measurement plate corresponding to the position to be measured can be quickly and accurately grasped, thereby shortening the wheel alignment measurement time. , While improving the measurement efficiency,
The reliability of the measurement can be improved.

According to the tenth aspect, the ninth aspect is provided.
In addition to the operation of the described invention, the concentric circle extracting step of the discriminating step extracts a concentric circle included in the imaging screen based on the imaging data, and the curvature calculating step calculates the curvature of the extracted concentric circle, and the concentric circle specifying step. Specifies the concentric circle having the curvature by comparing the curvature calculated by the curvature calculation means with the curvature stored in the storage means, so that the concentric circle included in the imaging screen can be reliably specified, and the accurate position can be determined. Since the identification can be performed, accurate wheel alignment measurement can be performed.

According to the eleventh aspect, in the imaging step, the test is performed such that at least a part of at least one of the plurality of concentric circles and at least a part of the graduation line are included in the imaging screen. The surface is imaged to generate image data, and the color separation step is to perform color separation of the image data to generate color separation image data, and based on the determination step, the color separation image data and the curvature of concentric circles in the image screen. It is determined which of the concentric circles is included in the imaging screen of the imaging means, and the scale line specifying step includes determining the scale lines included in the imaging screen based on the determination result and the color separation imaging data. The specifying and calculating step calculates a position on the measurement plate corresponding to the measurement target position based on the positional relationship between the specified scale line and the measurement target position in the imaging screen of the imaging unit. , Quickly position on measurement plate corresponding to the measurement object position, and can be calculated accurately, it is possible to improve the measurement efficiency of the wheel alignment measurement, thereby improving the reliability.

According to the twelfth aspect, according to the ninth aspect,
In addition to the effect of the invention according to any one of claims 11 to 11, in the spin angle calculation step, the spin angle is calculated by calculating the inclination of the graduation line in the imaging screen with respect to a predetermined reference position, so that the spin angle is simplified. In this way, an accurate spin angle can be calculated quickly. .

[Brief description of the drawings]

FIG. 1 is a schematic configuration block diagram of a wheel alignment measurement device.

FIG. 2 is a front view of a measurement plate.

FIG. 3 is an external perspective view of a measurement unit.

FIG. 4 is a schematic configuration block diagram of a processor main body.

FIG. 5 is a flowchart of a measurement operation process.

FIG. 6 is an operation explanatory diagram in a case where one concentric circle and two graduation lines are included in the imaging screen.

FIG. 7 is an operation explanatory diagram in a case where one concentric circle and one graduation line are included in the imaging screen.

[Explanation of symbols]

 Reference Signs List 1 wheel alignment measuring device 2 measuring vehicle 3 tire wheel 4 measuring plate 4S test surface 5 CCD camera 6 laser projector 7 measuring unit 7 8 data processing unit 8A processor body 8B display 8C keyboard 8D printer 10 holding plate 10A opening 11 Z-axis driving Knob 12 Z axis direction drive unit 13 Angle direction drive knob 14 Angle direction drive unit 15 Y axis direction drive knob 16 Y axis direction drive unit 17 X axis direction drive knob 18 X axis direction drive unit 18 19 Base unit 20 Guide rail 20 25 Controller 26 Interface unit 28 Arithmetic processing unit DCD image data DR Red image data DG Green image data DB Blue image data DLD1 to DLD4 Output signal DX X coordinate data Data DZ Z coordinate data DSP Inclination (spin angle) data C1 to C3 Concentric circle O Origin LX1 to LX7 Scale line LZ1 to LZ7 Scale line

Claims (12)

[Claims] 1. A plurality of concentric circles and a grid-like graduation line centered on a predetermined origin position are drawn on a test surface, and are mounted so that the origin position coincides with the center of a rotation axis of a wheel of a vehicle to be inspected. A measurement plate characterized in that: 2. The measurement plate according to claim 1, wherein the scale lines are a plurality of first scale lines parallel to each other, and a plurality of second scale lines intersecting the first scale lines and parallel to each other.
And a scale line, wherein the concentric circle, the first scale line, and the second scale line are drawn in different colors. 3. The measuring plate according to claim 2, wherein the concentric circle, the first graduation line, or the second graduation line is drawn in any one of red, green, and blue. . 4. A wheel alignment measuring device for measuring wheel alignment using the measuring plate according to claim 1, wherein at least one of the plurality of concentric circles is measured. Imaging means for imaging the test surface such that at least a part and at least a part of the scale line are included in the imaging screen; and which concentric circle is included in the imaging screen of the imaging means Determining based on the curvature of concentric circles in the imaging screen; scale line specifying means for specifying the scale line included in the imaging screen based on the determination result of the determination unit; A position on the measurement plate corresponding to the measurement target position is calculated based on a positional relationship between a line and a measurement target position in an imaging screen of the imaging unit. Wheel alignment measuring device, characterized in that it and a calculation unit. 5. The wheel alignment measuring device according to claim 4, wherein the discriminating unit stores the curvatures of the plurality of concentric circles in advance, and stores the curvature of the plurality of concentric circles in the imaging screen based on an output signal of the imaging unit. Concentric circle extraction means for extracting the concentric circles included; curvature calculation means for calculating the curvature of the extracted concentric circle; and comparing the curvature calculated by the curvature calculation means with the curvature stored in the storage means to calculate the curvature. A concentric circle specifying means for specifying a concentric circle having the same. 6. A wheel alignment measuring apparatus for measuring wheel alignment using the measuring plate according to claim 2 or 3, wherein at least a part of at least one of the plurality of concentric circles and Imaging means for imaging the test surface so that at least a part of the graduation line is included in an imaging screen and outputting imaging data; and color separation means for performing color separation of the imaging data and outputting color separation imaging data. A determination unit configured to determine which concentric circle is included in the imaging screen of the imaging unit based on the color separation imaging data and a curvature of a concentric circle in the imaging screen; A scale line specifying means for specifying the scale line included in the imaging screen based on the determination result and the color separation image data; and the specified scale line. Calculating means for calculating a position on the measurement plate corresponding to the measurement target position based on a positional relationship between the measurement target position in the imaging screen of the imaging means, and a wheel alignment measurement. apparatus. 7. The wheel alignment measuring device according to claim 6, wherein the discriminating unit is included in the imaging screen based on the color separation imaging data, based on the color separation imaging data, and a storage unit that stores in advance the curvatures of the plurality of concentric circles. Concentric circle extracting means for extracting the concentric circles to be extracted, curvature calculating means for calculating the curvature of the extracted concentric circles, and having the curvature by comparing the curvature calculated by the curvature calculating means with the curvature stored in the storage means. A wheel alignment measuring device, comprising: concentric circle specifying means for specifying concentric circles. 8. The wheel alignment measuring device according to claim 4, wherein a spin angle is calculated by calculating an inclination of the graduation line in the imaging screen with respect to a predetermined reference position. A wheel alignment measuring device comprising an angle calculating means. 9. A wheel alignment measuring method for measuring wheel alignment using the measuring plate according to claim 1, wherein at least one of the plurality of concentric circles is measured. An imaging step of imaging the test surface so that at least a part and at least a part of the graduation line are included in the imaging screen; and determining which concentric circle is included in the imaging screen. A discrimination step of discriminating based on the curvature of a concentric circle in the inside; a scale line specifying step of specifying the scale line included in the imaging screen based on the result of the discrimination; and the specified scale line and the inside of the imaging screen. A calculating step of calculating a position on the measurement plate corresponding to the measurement target position based on a positional relationship with the measurement target position. Wheel alignment measuring how. 10. The wheel alignment measuring method according to claim 9, wherein the discriminating step is a concentric circle extracting step of extracting a concentric circle included in the imaging screen based on the imaging data, and a curvature of the extracted concentric circle. And a concentric circle specifying step of specifying the concentric circle having the curvature by comparing the curvature calculated by the curvature calculating means with a previously stored curvature. Alignment measurement method. 11. A wheel alignment measuring method for measuring wheel alignment using the measuring plate according to claim 2 or 3, wherein at least a part of at least one of the plurality of concentric circles and An imaging step of imaging the test surface so that at least a part of the graduation line is included in an imaging screen and generating imaging data; and a color separation step of performing color separation of the imaging data to generate color separation imaging data. A determining step of determining which concentric circle is included in the imaging screen of the imaging unit based on the color separation imaging data and the curvature of the concentric circle in the imaging screen; and a result of the determination. And a scale line specifying step of specifying the scale line included in the imaging screen based on the color separation imaging data; and A calculating step of calculating a position on the measurement plate corresponding to the measurement target position based on a positional relationship between the measurement target position in the imaging screen of the imaging means, and a wheel alignment measurement method. . 12. The wheel alignment measuring method according to claim 9, wherein a spin angle is calculated by calculating an inclination of the graduation line in the imaging screen with respect to a predetermined reference position. A method for measuring wheel alignment, comprising an angle calculation step.