JPH0618224A - Method and apparatus for measuring accuracy in assemblage - Google Patents

Abstract

PURPOSE:To realize efficient noncontact measurement of split or surface level difference between members, e.g. between a vehicle body member and an assembling member or between adjacent assembling members, at a matching point in an assembly line with no limitation on the shape of the member. CONSTITUTION:A robot located on the side of an assembly line is provided with a measuring apparatus 14 comprising a laser light emitting body 14a and a CCD camera 14b wherein adjacent members 4, 9 irradiated with one- dimensional laser light traversing a matching point B to be measured from the laser light emitting body 14a and the irradiated states are read out by means of the CCD camera 14b. A control unit determines a pixel at a reference point based on a detection signal from the CCD camera 14b and then determines a split DA and a surface difference DB between both members 4, 9 through operation based on the pixel thus determined.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an assembling accuracy measuring method and an assembling accuracy measuring apparatus for measuring the consistency of building members and the like.

[0002]

2. Description of the Related Art For example, in an automobile manufacturing plant, in order to assemble building members such as a front hood, a trunk lid, a front door and a rear door to a vehicle body, a front fender, a rear quarter, Maintains proper assembly accuracy for the surface difference that is the gap between the body parts such as the rear skirt and the level difference between the mutual members, and between the adjacent building members such as the front and rear doors. It is desired to improve the quality and aesthetics of the vehicle body and reduce the number of man-hours for correction in the post process.

For this reason, after a building member such as a front hood or a trunk lid is attached to the vehicle body, each division and surface difference are measured by a worker using a measuring instrument such as a taper gauge or a caliper. .

On the other hand, as shown in FIG. 9 disclosed in Japanese Patent Laid-Open No. 61-98683 and showing a plan view of the essential parts of FIGS. 8 and 8, a door supported by a door assembling device is provided. A door assembling method in which the door assembling device is positioned at a door opening of a vehicle body based on a positioning operation of a door assembling apparatus and is automatically assembled, wherein an accent line 21 on a door 20 side and an accent line 23 on a vehicle body 22 side are provided. In the continuous portion of the door, the sensor 25 provided in the door assembling device 24 detects the vertical shift between the two and the door 2 supported by the door assembling device 24 based on the sensor output.
Correct the direction of 0 and accent line 21 on the door 20 side
There has been proposed a vehicle door assembling method for aligning the accent line 23 on the vehicle body 22 side with the vehicle body 22 side by side.

[0005]

In the measurement by the worker using the above-mentioned measuring instrument, the measurement work in which the worker measures each division and surface difference of each kind of building member one by one is troublesome, and the manufacturing process is difficult. It takes a huge number of man-hours to measure all the products, which are all products, and it is necessary to rely on the unannounced measurement, and there is a risk that the car body may be damaged by the contact of the measuring instrument. There is a defect of.

In the method of assembling a vehicle door disclosed in Japanese Patent Laid-Open No. 61-98683, a sensor detects a vertical shift of each accent line between the door and the vehicle body to detect the door. Since the orientation of the door is corrected, the shapes of the door and the vehicle body are limited, and it is difficult to apply the same to the front hood and the trunk lid. Further, since the sensor comes into contact with the vehicle body, the vehicle body may be damaged and the quality may be deteriorated.

Therefore, an object of the present invention is to measure the division and surface difference between the main body member, the building member, and the adjacent building members with each other within the assembly line and over all products conveyed by the assembly line. And an assembly accuracy measuring device capable of obtaining a high-quality product that is not limited to the shape of the building member and that is not likely to be scratched. .

[0008]

In order to achieve the above object, the method of measuring the assembling accuracy according to the present invention measures the assembling accuracy by measuring the division and the surface difference between the members at the matching points of the members adjacent to each other. In the method, the robot is provided with a measuring device equipped with a laser emitter and a CCD camera, and the two adjacent members are irradiated with a one-dimensional linear laser beam that crosses an alignment point to be measured by the laser emitter. Read the upper irradiation state with a CCD camera, and
The control unit obtains a pixel serving as a reference point in accordance with a detection signal from the CD camera, and obtains a division and a surface difference between both members by an arithmetic process based on the pixel. In the assembling accuracy measuring device for measuring the division and the surface difference between the members at the matching point of, a robot arranged on the side of the assembly line,
A measuring device provided on the robot and provided with a laser emitting body for irradiating adjacent members with a one-dimensional linear laser beam crossing the alignment point and a CCD camera for reading the irradiation state, and the operation of each of the devices. And a control unit that obtains a pixel serving as a reference point according to a detection signal from the CCD camera and obtains a division and a surface difference by a calculation process based on the pixel.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of an assembly accuracy measuring method and an assembly accuracy measuring device according to the present invention will be described below with reference to the drawings as an example of a case where an assembly accuracy measurement of an automobile body is performed.

FIG. 1 is an explanatory perspective view showing a use state of the assembling accuracy measuring apparatus 11 in this embodiment, FIG. 2 is a plan view thereof, and reference numeral 1 is an assembly line for carrying a vehicle body 2. The vehicle body 2 conveyed by the assembly line 1 includes a front fender 4, a rear quarter 5,
It has a vehicle body member such as the rear skirt 6 and a front hood 7, a front door 8, a rear door 9, a trunk lid 10 and the like, which are building members.

An assembling accuracy measuring device 11 is arranged on the side of the assembly line 1 which serves as the measuring station I. The assembling accuracy measuring device 11 is separated from the assembly line 1 by the assembly line 1
A pair of guide rails 12 arranged along the guide rails, a robot 13 that reciprocates on the guide rails 12, and a robot 13.
Measuring device 14 provided at the arm tip 13a of the vehicle, assembly specifications such as a vehicle type of the vehicle body 2 that is provided at an appropriate position on the side of the assembly line 1, and is conveyed along the assembly line 1 and a stop position of the vehicle body 2 Reading device 15 for reading an image, reading device 15
The control unit 16 for operating each device according to the detection signal from the robot 1 and the robot 1 according to the signal from the control unit 16
The robot controller 17 which gives a control instruction to 3 is the main constituent device.

The vehicle body 2 conveyed by the assembly line 1 is stopped at the measuring station I in which the assembling accuracy measuring device 11 is installed, and the vehicle body 2 is read by the reading device 15.
The assembly specification and the accurate stop position of the device are detected, and the detection signal is transmitted to the control unit 16. Measurement conditions such as measurement points in each assembly specification are input to the control unit 16 in advance, and the measurement apparatus 15 is installed at the measurement location corresponding to the assembly specification of the vehicle body 2 conveyed based on the detection signal from the reader 15. The robot controller 17 is instructed to move, and the robot controller 17 instructs the robot controller 17 to move the robot 13 along the guide rails 12 and swing the robot arm.

The measuring points of the division and surface difference by the measuring device 14 are, for example, hatched front fender 4 and front hood 7, front fender 4 and front door 8, front door 8 and rear door 9, rear door 9 and rear quarter 5, rear quarter. 5 and the trunk lid 10, and the matching points A such as the trunk lid 10 and the rear skirt 6,
B, ... F.

The measuring device 14 provided at the arm tip 13a of the robot 13 has a perspective view as shown in FIG.
The laser light emitter 14a and the CCD camera 14b are provided, and the laser light emitter 14a irradiates a measurement point, for example, a matching point B between the front fender 4 and the front door 8 with a one-dimensional linear laser beam, and the irradiated state. CCD
A division D between the front fender 4 and the front door 8 is provided between the end points on the front fender 4 and the front door 8 where the irradiation is interrupted in the portion irradiated by the camera 14b.
Assumed to be A, an arithmetic unit 14c attached to the measuring device 14 or a control unit 16 separately arranged based on the information.
The pixel of the end point is obtained by calculating the division DA by calculating the numerical data based on the pixel, and the pixel of the point on the irradiation that is separated from the both end points by a predetermined distance, and calculating the numerical data based on this pixel. Thus, the surface difference between the front fender 4 and the front door 8 is obtained. The suitability of the assembling accuracy of these divided DA and surface difference DB is determined and displayed.

The other matching points A, C ... F are measured by such a measuring method, and the suitability of the assembling accuracy of each division and surface difference is judged and displayed.

Next, the measuring method by the assembling accuracy measuring apparatus thus constructed will be described in detail with reference to the flow chart shown in FIG. 4 and the explanatory views shown in FIGS.

An object to be measured in which a front hood 7, a front door 8, a rear door 9 and a trunk lid 10, which are building members, are attached to a vehicle body 3 composed of a front fender 4, a rear quarter 5, a rear skirt 6 and other members. The vehicle body 2 to be described is carried into the measuring station I by the assembly line 1 and stopped at a predetermined position (step 1).

The vehicle body 2 carried into the predetermined position of the measuring station I in step 1 is managed by the reading device 15 according to the instruction of the control unit 16. Information necessary for measurement such as vehicle type, assembly specifications, and accurate stop position is read (step 2), and the detection signal is input to the control unit 16.

The control unit 16 to which the detection signal corresponding to the loaded vehicle body 2 is input selects the measurement condition corresponding to the vehicle body from various measurement conditions input in advance, and according to the assembly specifications of the vehicle body. Robot 13 to operate
Give instructions to. By this instruction, the robot 13 is moved along the guide rail 12 and the arm is rocked to be moved to the alignment point to be measured, for example, the alignment point B by the measuring device 14 provided at the arm tip 13a (step 3), and the alignment point. The divided DA of B and the surface difference DB are measured, and these measurement results are compared with a predetermined reference value to determine the suitability of the measurement results (step 4).

The measurement of the division of the matching point B and the determination of suitability in step 4 will be described with reference to the flowcharts shown in FIGS. 5 and 6 which are VV sectional views taken along the one-dimensional linear laser beam in FIG. In the present invention, the laser light emitter 14a is a one-dimensional line extending in the front-rear direction of the vehicle body 2 by the laser light, and has a front fender 4 and a front door 8.
The CCD camera 14b reads the irradiation state, and the control unit 16 performs image processing. The coordinate system for image processing is the Y-axis in the front-rear direction of the vehicle and the Z-direction in the vehicle width direction.
It is assumed that the shaft is an axis and the front door 8 projects outward from the front fender 4 by a surface difference DB.

In step a, the end point of the front door 8 where the irradiation is interrupted is regarded as the front end of the front door 8 and the CCD
It is read by the camera and the pixel No. of the division reference point G ₁ is read. (Y
a, Za), and similarly in the subsequent step b, the pixel No. of the division reference point G ₂ on the rear end side of the front fender 4 is determined.
Calculate (Yb, Zb). Next, in step c, the difference (Ya-Yb) in the Y coordinate between the division reference points G ₁ and G ₂ is obtained and used as the division DA. The difference between the Y coordinates (Ya-Yb) is compared with a reference value which is preset and input in the next step d to determine whether or not it is appropriate, and the result is stored (step e) and the matching point b is stored. Complete the measurement and determination of the divided DA.

Similarly, the surface difference measurement and suitability determination of the matching point B in step 4 will be described with reference to the flowcharts shown in FIGS. 6 and 7.

First, in step f, since the front end of the front door 8 is bent back, in order to obtain an accurate value, the divided reference point G ₁ excluding this curved portion is separated by a predetermined distance a _{1 in the} Y-axis direction. An irradiation point on the front door 8 is set as a surface difference reference point Pa ₁ and its pixel number. Ask for.

[0024] Next define the point on the front door 8, wherein from division criterion G ₁ Y-axis direction to leave a predetermined dimension a ₂ of the front door 8 and the plane difference reference point Pa ₂ in the following step g, the pixel No. Ask for.

In the next step h, the front fender 4
The point on the front fender 4 which is separated from the division reference point G ₂ by a predetermined dimension b _{1 in the} Y-axis direction in order to avoid the bent back portion of the front end is defined as the surface difference reference point Pb ₁ and its pixel No. Ask for.

In the subsequent step i, the surface difference reference point Pa ₁
Y coordinate and Y coordinate (Ya + a ₁ , Za ₁ ) of P2 are calculated, and the Y coordinate and Z coordinate (Ya + a ₂ , Za) of Pa ₂ are calculated in step j.
₂₎ determining the Y-coordinate and Z coordinate of the surface difference reference point _{Pb 1 (Yb-b 1,} Zb 1) in step k.

In the next step l, the surface difference reference point Pa ₁
And the pixel No. of the middle point Pac on the front door 8 of Pa ₂ .
And the surface difference reference points Pa ₁ and Pa _{2 at} step m.
The Z coordinate at the midpoint pixel on the straight line connecting the two is calculated.

In the subsequent step n, these surface difference reference points Pa
An arc a formed by the front door 8 from ₁ , ₁ , Pa ₂ , Pb ₁ and a midpoint on a straight line connecting the surface difference reference points Pa ₁ and Pa ₂
The Z-coordinate and the Y-coordinate of the center point of are calculated, and the surface difference DB between the front fender 4 and the front door 8 is calculated from these.

This surface difference DB is compared with a reference value which is preset and input in the next step o to judge and display the suitability of the surface difference DB, and the result is stored in step p to store the matching point. The measurement and determination of the surface difference DB of B are completed.

By such a method, the assembling accuracy measurement of the division and the surface difference at the preset matching points A to F and the suitability determination are executed.

After the division of the matching points A to F and the measurement of the surface difference and the determination of suitability are completed in step 4, the robot 13 is returned to the original state in step 5, and the measurement is completed in step 6. The completed vehicle body 2 is unloaded, and the operation is completed by waiting for the measurement of the next transported vehicle body.

[0032]

As described above, according to the present invention, it is possible to efficiently measure the assembling accuracy of the division and the surface difference between the members at the matching points of the members adjacent to each other in the contacted state by the measuring device provided in the robot. In addition to improving the aesthetics and quality of the product, contact scratches that occur on the product can be prevented, and the number of correction steps in the subsequent steps can be reduced.

[Brief description of drawings]

FIG. 1 is an explanatory perspective view illustrating an embodiment of an assembly accuracy measuring method and an assembly accuracy measuring apparatus for an automobile body of the present invention.

FIG. 2 is likewise a plan view of FIG.

FIG. 3 is likewise an explanatory view of a main part of the assembling accuracy measuring method and the assembling accuracy measuring device.

FIG. 4 is likewise a flowchart illustrating a measuring method.

FIG. 5 is likewise a cross-sectional explanatory view taken along the line VV in FIG.

FIG. 6 is likewise a flowchart illustrating a measuring method.

FIG. 7 is likewise a flowchart illustrating a measuring method.

FIG. 8 is an explanatory diagram illustrating a conventional method.

FIG. 9 is an explanatory diagram similarly illustrating a conventional method.

[Explanation of symbols]

 1 ... Assembly line 2 ... Car body 3 ... Car body 4 ... Front fender (car body member) 5 ... Rear quarter (car body member) 6 ... Rear skirt (car body member) 7 ... Front hood (building member) 8 ... Front door ( Building member 9 ... Rear door (building member) 10 ... Trunk lid (building member) 11 ... Assembly accuracy measuring device 13 ... Robot 13a ... Arm tip 14 ... Measuring device 14a ... Laser light emitter 14b ... CCD camera 14c ... Computation unit 15 ... Reading device 16 ... Control unit A ... Alignment point to be measured B ... Alignment point to be measured C ... Alignment point to be measured D ... Alignment point to be measured E ... Alignment point to be measured F ... Alignment point to be measured Matching point

Claims (5)

[Claims] 1. A method for measuring an assembling accuracy for measuring division and surface difference between members at alignment points of members adjacent to each other, wherein a robot is provided with a measuring device equipped with a laser emitter and a CCD camera to emit laser light. Both adjacent members are irradiated with a one-dimensional linear laser beam that crosses the matching point to be measured by the body, the irradiation state on both members is read by the CCD camera, and the reference is made by the control unit according to the detection signal from the CCD camera. An assembling accuracy measuring method characterized in that a pixel which becomes a point is obtained, and a division and a surface difference between both members are obtained by an arithmetic processing based on the pixel. 2. The division reference points are both end points on the member where the irradiation with the one-dimensional linear laser light is interrupted, and the reference point of the surface difference is on the irradiation of each member separated from the end point by a predetermined distance. The assembly accuracy measuring method according to claim 1, which is the point. 3. An assembly accuracy measuring apparatus for measuring division and surface difference between members at alignment points of members adjacent to each other, a robot arranged laterally on an assembly line, and a robot provided on the robot, A measuring device equipped with a laser emitting body that irradiates both adjacent members with a one-dimensional linear laser beam that crosses the alignment point and a CCD camera that reads the irradiation state; and an instruction to operate each device, and C
An assembling accuracy measuring device, comprising: a control unit that obtains a pixel serving as a reference point according to a detection signal from a CD camera, and obtains a division and a surface difference by arithmetic processing based on the pixel. 4. The division reference points are both end points on the member where the irradiation with the one-dimensional linear laser beam is interrupted, and the reference point of the surface difference is the irradiation on each member separated by a predetermined distance from the both end points. The assembly accuracy measuring device according to claim 3, which is the above point. 5. The assembly according to claim 3, wherein a reading device for reading the assembly specifications of the vehicle body conveyed by the assembly line is provided on the side of the assembly line, and the control unit is activated by a detection signal of the reading device. Accuracy measuring device.