Motor stator installation method based on robot and industrial vision

Abstract

The invention discloses a motor stator installation method based on a robot and industrial vision. The motor stator installation method comprises the following steps that the tail end of a first six-axis robot carries an industrial camera to move to a designated station; an industrial camera of the first six-axis robot recognizes the position of the iron core; the first six-axis robot moves to the iron core position to clamp an iron core workpiece; the first six-axis robot carries the iron core workpiece to move to a designated coordinate point of an assembling area of the base, and rough assembling of the iron core base is carried out; the tail end of the second six-axis robot carries an industrial camera to inspect the position of the temperature measuring hole around the Z axis of the base, and the position of the temperature measuring hole in the base is found; the first six-axis robot drives the iron core to rotate, and an industrial camera of the second six-axis robot continuously collects images of the temperature measuring hole of the base till the temperature measuring hole of the iron core coincides with the temperature measuring hole of the base. According to the invention, the assembly operation of the stator core and the base of the motor is automatically completed, the iron core temperature measuring hole and the base temperature measuring hole are intelligently aligned, and the assembly precision and the assembly efficiency can be ensured.

Description

Technical Field

[0001] The invention belongs to the field of motor assembly and robot technology, and specifically relates to a motor stator installation method based on robots and industrial vision. Background Art

[0002] Large motors are widely used in high-speed railways, subways, and various industrial applications. The temperature of the motor during operation is an important indicator that is widely concerned. Therefore, in the assembly process of large motors, it is necessary to install a temperature measuring device at the temperature measuring hole fixed on the motor housing to detect the motor operating temperature to determine the motor status. Therefore, it is necessary to ensure that the motor stator and the base are assembled at a specified angle during the motor assembly process, so as to ensure that the base temperature measuring hole and the stator temperature measuring hole coincide to ensure the subsequent installation of the temperature sensor. Existing motor assembly generally relies on the coordinated adjustment and installation of multiple people, and the motor stator assembly is mostly an interference fit after heating. This installation method consumes a lot of labor costs, and there is a certain risk of installation failure during assembly as the base cools. Summary of the invention

[0003] The purpose of the present invention is to provide a motor stator installation method based on robots and industrial vision, which can automatically complete the assembly operation of the motor stator core and the base, and intelligently align the core temperature measuring holes and the base temperature measuring holes, thereby ensuring both the assembly accuracy and the assembly efficiency.

[0004] To achieve the above objectives, the technical solutions adopted are as follows:

[0005] A motor stator installation method based on robot and industrial vision includes the following steps:

[0006] S1, the end of the No. 1 six-axis robot carries the industrial camera and moves to the designated workstation;

[0007] S2, the industrial camera of the No. 1 six-axis robot recognizes the position of the iron core;

[0008] S3, six-axis robot No. 1 moves to the core position to clamp the core workpiece;

[0009] S4, the No. 1 six-axis robot carries the iron core workpiece and moves to the specified coordinate point in the assembly area of ​​the base to perform rough assembly of the iron core base;

[0010] S5, the end of the No. 2 six-axis robot carries an industrial camera around the Z axis of the base to patrol the temperature measurement hole position and find the temperature measurement hole position on the base;

[0011] S6, the No. 1 six-axis robot rotates with the iron core, and the industrial camera of the No. 2 six-axis robot continuously collects images of the temperature measuring holes of the base until the temperature measuring holes of the iron core and the temperature measuring holes of the base coincide.

[0012] Preferably, in S2, the specific steps for the industrial camera of the No. 1 six-axis robot to recognize the position of the iron core are:

[0013] S201, the specific formula for calculating the coordinate transformation T is as follows:

[0014] T=j m *(c m ) -1

[0015] In the formula, j m is the calibrated robot coordinate, c m is the calibrated industrial camera coordinate, T is the transformation matrix;

[0016] S202, the industrial camera of the No. 1 six-axis robot recognizes the specified workpiece and converts the corresponding workpiece coordinates into the workpiece coordinates corresponding to the robot. The specific formula is as follows:

[0017] j P =T*c P

[0018] Where: j P is the workpiece coordinate corresponding to the robot, c P is the workpiece coordinate corresponding to the industrial camera, and T is the transformation matrix.

[0019] Preferably, in S5, the end of the No. 2 six-axis robot carries an industrial camera to patrol the position of the temperature measuring hole around the Z axis of the base. The specific steps for finding the position of the temperature measuring hole on the base are: the circumference of the base is divided into several areas around the Z axis, and the end of the No. 2 six-axis robot carries an industrial camera to patrol the divided areas in turn around the Z axis of the base in a clockwise direction, continuously collect images of the temperature measuring holes of the base, and judge the position of the temperature measuring holes of the base. If the position of the temperature measuring holes of the base exists, the position judgment result is Then the industrial camera of the No. 2 six-axis robot stops collecting images; if the position judgment result of the base temperature measurement hole exists The industrial camera of six-axis robot No. 2 continues to collect images.

[0020] Preferably, the position of the temperature measuring hole of the base is determined and a determination model is established:

[0021]

[0022] Where: To collect data, (x, y) is the image coordinate, μ(x, y) is the reference image grayscale value, μ'(x, y) is the acquisition image grayscale value, To determine the threshold, The result is the temperature measuring hole position, The result is the non-temperature measuring hole position.

[0023] Preferably, in S6, the six-axis robot No. 1 rotates with the iron core, and the industrial camera of the six-axis robot No. 2 continuously collects images of the temperature measuring holes of the base until the temperature measuring holes of the iron core and the temperature measuring holes of the base overlap. The specific steps are:

[0024] The No. 1 six-axis robot rotates with the core, and the No. 2 six-axis robot's industrial camera continuously collects images of the base temperature measuring holes to determine the overlap between the core temperature measuring holes and the base temperature measuring holes. If the overlap between the core temperature measuring holes and the base temperature measuring holes is Then the six-axis robot No. 1 stops rotating, and the industrial camera of the six-axis robot No. 2 stops collecting images;

[0025] If the core temperature measuring hole and the base temperature measuring hole coincide with each other, the result will be Then the six-axis robot No. 1 continues to rotate, and the industrial camera of the six-axis robot No. 2 continues to collect images.

[0026] Preferably, the overlap between the core temperature measuring hole and the base temperature measuring hole is determined, and a determination model is established:

[0027]

[0028] Where: To collect data, (x, y) is the image coordinate, μ(x, y) is the gray value of the standard coincident image, μ'(x, y) is the gray value of the collected temperature measurement hole image, To determine the threshold, The result is that the temperature measuring hole of the core coincides with the temperature measuring hole of the base. The result is that the core temperature measuring hole does not coincide with the base temperature measuring hole

[0029] Preferably, when the No. 1 six-axis robot has an iron core, each time it rotates a fixed angle α, the specific formula for the rotation speed V(n+1) of the No. 1 six-axis robot at the next rotation of the fixed angle α is:

[0030]

[0031] Where n is the number of image comparisons, To determine the result, v is the rotation speed of the No. 1 six-axis robot at a fixed angle α.

[0032] The beneficial effects of the present invention are:

[0033] The present invention is based on a visual inspection + robot collaborative control method to automatically complete the assembly operation of the motor stator core and the base, and intelligently align the core temperature measuring holes and the base temperature measuring holes, which can ensure both the assembly accuracy and the assembly efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 The figure is a flow chart of the method of the present invention.

[0035] Figure 2 It is a schematic diagram of the temperature measuring holes of the iron core and the base of the present invention.

[0036] Figure 3 It is a flow chart of the present invention. DETAILED DESCRIPTION

[0037] In order to make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be clearly and completely described below in conjunction with the accompanying drawings of the present invention.

[0038] like Figure 1-Figure 3 As shown, a motor stator installation method based on robot and industrial vision includes the following steps:

[0039] S1, the end of the No. 1 six-axis robot carries an industrial camera and moves to the designated workstation.

[0040] An industrial camera is installed at the end of the No. 1 six-axis robot, and the No. 1 six-axis robot clamps and carries the fixture to the specified coordinate point.

[0041] S2, the industrial camera of the No. 1 six-axis robot recognizes the position of the iron core.

[0042] S201, if the number of coordinate points P is greater than the dimension of the transformation matrix T and the coordinate points are nonlinearly related, the coordinate transformation matrix T can be solved to facilitate coordinate transformation.

[0043] The specific formula for calculating the coordinate transformation T is as follows:

[0044] T=j m *(c m ) -1

[0045] In the formula, j m is the calibrated robot coordinate, c m is the calibrated industrial camera coordinate, and T is the transformation matrix.

[0046] S202, the industrial camera of the No. 1 six-axis robot recognizes the specified workpiece and converts the corresponding workpiece coordinates into the workpiece coordinates corresponding to the robot. The specific formula is as follows:

[0047] j P =T*c P

[0048] Where: j P is the workpiece coordinate corresponding to the robot, c P is the workpiece coordinate corresponding to the industrial camera, and T is the transformation matrix.

[0049] Six-axis robot No. 1 obtains the workpiece coordinates corresponding to the robot and identifies the position of the iron core.

[0050] S3, six-axis robot No. 1 moves to the core position to clamp the core workpiece.

[0051] Six-axis robot No. 1 moves to the workpiece coordinate corresponding to the robot to clamp the iron core workpiece.

[0052] S4, six-axis robot No. 1 carries the core workpiece to the specified coordinate point in the assembly area of ​​the base to perform rough assembly of the core base.

[0053] The No. 1 six-axis robot carries the core workpiece to the specified coordinate point in the assembly area of ​​the base to perform roughing of the core base.

[0054] S5, the end of the No. 2 six-axis robot carries an industrial camera around the Z-axis of the base to patrol the temperature measurement hole position and find the temperature measurement hole position on the base.

[0055] Collect the reference image of the workpiece without the temperature measuring hole area, and use grayscale processing on the reference image to obtain the reference grayscale image without the temperature measuring hole area, mark the pixels in this grayscale image as reference image pixels, and record the grayscale value of the marked reference pixel as the reference image grayscale value. This part of the data has been prepared in advance when the motor stator is installed.

[0056] The pixels in the grayscale image of the collected divided area are recorded as collected image pixels, and the grayscale values ​​of the collected image pixels are recorded as collected image grayscale values.

[0057] Determine the position of the temperature measuring hole on the base and further establish a judgment model:

[0058]

[0059] Where: To collect data, (x, y) is the image coordinate, μ(x, y) is the reference image grayscale value, μ'(x, y) is the acquisition image grayscale value, To determine the threshold, The result is the temperature measuring hole position. The result is the non-temperature measuring hole position.

[0060] like Figure 2 As shown, the angle between the core temperature measuring hole and the base temperature measuring hole in the X plane is not fixed, and the height on the Z axis is a constant.

[0061] The circumference of the base is divided into several areas around the Z axis. The end of the No. 2 six-axis robot carries an industrial camera around the Z axis of the base in a clockwise direction to inspect the divided areas in turn, continuously collect images of the base temperature measuring holes, and determine the location of the base temperature measuring holes. If the base temperature measuring holes exist, the position judgment result The industrial camera of the No. 2 six-axis robot stops collecting images. If the position judgment result of the base temperature measurement hole exists The industrial camera of six-axis robot No. 2 continues to collect images.

[0062] S6, the No. 1 six-axis robot rotates with the iron core, and the industrial camera of the No. 2 six-axis robot continuously collects images of the temperature measuring holes of the base until the temperature measuring holes of the iron core and the temperature measuring holes of the base coincide.

[0063] The image where the core temperature measuring hole and the base temperature measuring hole completely overlap is set as the reference image, and grayscale processing is performed to obtain a standard grayscale image. The pixels in the standard grayscale image are recorded as standard coincidence image pixels, and the grayscale value of the standard pixel is set as the standard coincidence image grayscale value. This part of the data has been prepared in advance when the motor stator is installed.

[0064] The pixels in the grayscale image of the temperature measuring hole of the acquisition base are recorded as the acquisition coincidence image pixels, and the grayscale values ​​of the acquisition image pixels are recorded as the acquisition temperature measuring hole image grayscale values.

[0065] Determine the overlap between the core temperature measuring hole and the base temperature measuring hole, and further establish a judgment model:

[0066]

[0067] Where: To collect data, (x, y) is the image coordinate, μ(x, y) is the gray value of the standard coincident image, μ'(x, y) is the gray value of the collected temperature measurement hole image, To determine the threshold, The result is that the temperature measuring hole of the core coincides with the temperature measuring hole of the base. The result is that the temperature measuring hole of the core does not coincide with the temperature measuring hole of the base.

[0068] The No. 1 six-axis robot rotates with the core, and the No. 2 six-axis robot's industrial camera continuously collects images of the base temperature measuring holes to determine the overlap between the core temperature measuring holes and the base temperature measuring holes. If the overlap between the core temperature measuring holes and the base temperature measuring holes is Then the six-axis robot No. 1 stops rotating, and the industrial camera of the six-axis robot No. 2 stops collecting images.

[0069] If the core temperature measuring hole and the base temperature measuring hole coincide with each other, the result will be Then the six-axis robot No. 1 continues to rotate, and the industrial camera of the six-axis robot No. 2 continues to collect images.

[0070] To ensure the detection accuracy, the diameter of the temperature measuring hole needs to be larger than the arc length of a single rotation, that is,

[0071] L>τ(α*r)

[0072] Where: L is the diameter of the temperature measuring hole, τ is a constant, α is the rotation angle, and r is the radius of the core.

[0073] The rotation angle α is reasonably set according to expert experience to ensure detection accuracy.

[0074] When the No. 1 six-axis robot carries an iron core, it rotates a fixed angle α each time. To further increase the inspection speed, after rotating the fixed angle α, the rotation speed of the No. 1 six-axis robot is dynamically adjusted after each interval Δt.

[0075] The specific formula for the rotation speed V(n+1) of the next rotation of the No. 1 six-axis robot at a fixed angle α is:

[0076]

[0077] Where n is the number of image comparisons, To determine the result, v is the rotation speed of the No. 1 six-axis robot at a fixed angle α.

Claims

1. A motor stator installation method based on robot and industrial vision, characterized in that: The following steps are involved: S1, the end of the No. 1 six-axis robot carries the industrial camera and moves to the designated workstation; S2, the industrial camera of the No. 1 six-axis robot recognizes the position of the iron core; S3, six-axis robot No. 1 moves to the core position to clamp the core workpiece; S4, the No. 1 six-axis robot carries the iron core workpiece and moves to the specified coordinate point in the assembly area of ​​the base to perform rough assembly of the iron core base; S5, the end of the No. 2 six-axis robot carries an industrial camera around the Z axis of the base to patrol the temperature measurement hole position and find the temperature measurement hole position on the base; S6, the No. 1 six-axis robot rotates with the iron core, and the industrial camera of the No. 2 six-axis robot continuously collects images of the temperature measuring holes of the base until the temperature measuring holes of the iron core and the temperature measuring holes of the base coincide.

2. The motor stator installation method based on robot and industrial vision according to claim 1 is characterized in that: In S2, the specific steps for the industrial camera of the No. 1 six-axis robot to recognize the position of the iron core are: S201, the specific formula for calculating the coordinate transformation T is as follows: T=j m *(c m ) -1 In the formula, j m is the calibrated robot coordinate, c m is the calibrated industrial camera coordinate, T is the transformation matrix; S202, the industrial camera of the No. 1 six-axis robot recognizes the specified workpiece and converts the corresponding workpiece coordinates into the workpiece coordinates corresponding to the robot. The specific formula is as follows: j P =T*c P Where: j P is the workpiece coordinate corresponding to the robot, c P is the workpiece coordinate corresponding to the industrial camera, and T is the transformation matrix.

3. The motor stator installation method based on robot and industrial vision according to claim 1 is characterized in that: In S5, the end of the No. 2 six-axis robot carries an industrial camera to patrol the position of the temperature measuring hole around the Z axis of the base. The specific steps for finding the position of the temperature measuring hole on the base are: the circumference of the base is divided into several areas around the Z axis, and the end of the No. 2 six-axis robot carries an industrial camera to patrol the divided areas in turn around the Z axis of the base in a clockwise direction, continuously collect images of the temperature measuring hole of the base, and judge the position of the temperature measuring hole of the base. If the temperature measuring hole of the base exists, the position judgment result Then the industrial camera of the No. 2 six-axis robot stops collecting images; If the base temperature measurement hole has a position judgment result The industrial camera of six-axis robot No. 2 continues to collect images.

4. The motor stator installation method based on robot and industrial vision according to claim 3 is characterized in that: Determine the position of the temperature measuring hole on the base and establish a judgment model: Where: To collect data, (x, y) is the image coordinate, μ(x, y) is the reference image grayscale value, μ'(x, y) is the acquisition image grayscale value, To determine the threshold, The result is the temperature measuring hole position, The result is the non-temperature measuring hole position.

5. The motor stator installation method based on robot and industrial vision according to claim 1 is characterized in that: In S6, the six-axis robot No. 1 rotates with the iron core, and the industrial camera of the six-axis robot No. 2 continuously collects images of the temperature measuring holes of the base until the temperature measuring holes of the iron core and the temperature measuring holes of the base overlap. The specific steps are: The No. 1 six-axis robot rotates with the core, and the No. 2 six-axis robot's industrial camera continuously collects images of the base temperature measuring holes to determine the overlap between the core temperature measuring holes and the base temperature measuring holes. If the overlap between the core temperature measuring holes and the base temperature measuring holes is Then the six-axis robot No. 1 stops rotating, and the industrial camera of the six-axis robot No. 2 stops collecting images; If the core temperature measuring hole and the base temperature measuring hole coincide with each other, the result will be Then the six-axis robot No. 1 continues to rotate, and the industrial camera of the six-axis robot No. 2 continues to collect images.

6. The motor stator installation method based on robot and industrial vision according to claim 5 is characterized in that: Determine the overlap between the core temperature measuring hole and the base temperature measuring hole, and establish a judgment model: Where: To collect data, (x, y) is the image coordinate, μ(x, y) is the gray value of the standard coincident image, μ'(x, y) is the gray value of the collected temperature measurement hole image, To determine the threshold, The result is that the temperature measuring hole of the core coincides with the temperature measuring hole of the base. The result is that the temperature measuring hole of the core does not coincide with the temperature measuring hole of the base.

7. The motor stator installation method based on robot and industrial vision according to claim 5 is characterized in that: When the No. 1 six-axis robot has an iron core, each time it rotates a fixed angle α, the specific formula for the rotation speed V(n+1) of the No. 1 six-axis robot at the next rotation of the fixed angle α is: Where n is the number of image comparisons, To determine the result, v is the rotation speed of the No. 1 six-axis robot at a fixed angle α.

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