CN106341956A - Fixed camera calibration method - Google Patents

Abstract

The invention discloses a fixed camera correction method, relates to the field of machine vision positioning detection, and belongs to the high-precision correction process of a placement machine. The invention mainly solves the problem that the position, scale and rotation angle of the camera cannot be accurately measured in the equipment coordinate system when the fixed camera of the existing placement machine is mechanically installed. The present invention uses the calibration nozzle head to determine the positional relationship of the patch head in the fixed camera, calculates and deduces the conversion relationship between the two coordinate systems; calculates the scale of the fixed camera through the position coordinates of the center of the circle; The value coordinate of the film title is used to calculate the rotation angle of the fixed camera in the device coordinate system. By correcting the coordinates, rotation angle and scale of the fixed camera, the deviation caused by manual installation to the detection process is compensated, the accuracy of the placement machine for the detection and positioning of the calibration point is improved, and the placement effect of the placement machine is improved. The invention is applicable to the precision correction field of machine vision.

Description

A Fixed Camera Correction Method

technical field

The invention relates to a fixed camera calibration method, which belongs to the technical field of machine vision positioning detection.

technical background

In the SMT placement machine, the fixed camera is fixedly installed on the immovable fixed frame. When carrying out the patch production process, it is first necessary to accurately obtain the values of parameters such as the position, scale, and rotation angle of the fixed camera, so that the zero point of the system, the origin coordinate system of the reference camera, and other related information can be accurately found later. Accurate measurement of parameters such as fixed camera position, scale, and rotation angle determines whether the coordinate system of the entire placement machine system can be accurately constructed, which affects the positioning accuracy of the placement chip during the placement production process. When the fixed camera of the existing placement machine is installed manually, the deviation caused by manual installation cannot be avoided, and the error is relatively large.

Contents of the invention

In order to overcome the technical deficiencies of the manual mechanical installation of the fixed camera of the existing placement machine, which cannot avoid the deviation caused by manual installation and the large error, the present invention provides a method for correcting the fixed camera based on machine learning positioning detection technology ,include:

Step 1: Initialize the camera settings of the placement machine, set the moving length A of the placement head when the fixed camera is corrected, the unit is mm, after the No. 1 placement head absorbs the calibration nozzle from the ANC nozzle slot, move to the top of the fixed camera field of view, and calibrate The target object is to calibrate the nozzle head;

Step 2: Set the position of the No. 1 placement head in the equipment coordinate system as the initial position at this moment, first move the No. 1 placement head along the negative direction of the x-axis of the equipment coordinate system for a length of A/2, and then call the image detection program to obtain Calibrate the position coordinates of the center of the nozzle head in the fixed camera, which is recorded as D1(x ₁ , y ₁ ); then move the No. 1 placement head back to the initial position, and then move the No. 1 placement head along the positive direction of the x-axis of the equipment coordinate system Move the length of A/2, call the image detection program, and get the position coordinates of the center of the calibrated nozzle head in the fixed camera, which is recorded as D2 (x2, y2); move the No. 1 placement head back to the initial position, and then move the No. Move the length of A/2 in the negative direction of the y-axis of the equipment coordinate system, call the image detection program, and obtain the position coordinates of the center of the calibrated nozzle head in the fixed camera, which is recorded as D3 (x3, y3); then move the No. 1 patch head back to The initial position, and then move the No. 1 patch head along the positive direction of the y-axis of the equipment coordinate system for a length of A/2, call the image detection program, and obtain the position coordinates of the center of the calibrated nozzle head in the fixed camera, which is recorded as D4(x ₄ , y ₄ ), the unit of the position coordinates is mm;

Step 3: Move No. 1 placement head back to the initial position defined in step 2, rotate No. 1 placement head to the positions of 0°, 90°, 180° and 270° in the equipment coordinate system, and call the image detection program , according to the four angles of rotation, the position coordinates of the center point of the calibration nozzle head in the fixed camera are obtained, which are respectively recorded as (x ₀ , y ₀ ), (x ₉₀ , y ₉₀ ), (x ₁₈₀ , y ₁₈₀ ) and (x ₂₇₀ , y ₂₇₀ ), the units are pixels; and record the position coordinates (x _equipment , y _equipment ) of No. is the origin of the patch head coordinate system;

Step 4: Rotate the No. 1 patch head to the 360° position in the equipment coordinate system, which is the initial position defined in Step 2, and repeat Step 2 to obtain 4 sets of position coordinates D′ ₁ (x′ ₁ ,y′ ₁ ), D′ ₂ (x′ ₂ ,y′ ₂ ), D′ ₃ (x′ ₃ ,y′ ₃ ), D′ ₄ (x′ ₄ ,y′ ₄ ), the unit is pixel;

Step 5: Calculate and obtain 4 rotation angles θ ₁ , θ ₂ , θ′ ₁ and θ′ ₂ according to the 8 moving position coordinates of the patch head obtained in steps 2 and 4, and finally fix the camera coordinate system in the device coordinate system The rotation angle is The specific process is:

Step 51: Calculate the angle of the straight line formed by points 1 and 2 and points 3 and 4 in the image coordinate system:

$\left\{\begin{array}{c}{\mathrm{<span\; class="notranslate">\; \&theta;</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}<span\; class="notranslate">\; =</span>{\mathrm{<span\; class="notranslate">\; the\; tan</span>}}^{<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; 1</span>}}\frac{{\mathrm{<span\; class="notranslate">\; the\; y</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; the\; y</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}}}{{\mathrm{<span\; class="notranslate">\; x</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; x</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}}\\ {\mathrm{<span\; class="notranslate">\; \&theta;</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; =</span>{\mathrm{<span\; class="notranslate">\; the\; tan</span>}}^{<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; 1</span>}}\frac{{\mathrm{<span\; class="notranslate">\; x</span>}}_{\mathrm{<span\; class="notranslate">\; 3</span>}}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; x</span>}}_{\mathrm{<span\; class="notranslate">\; 4</span>}}}{{\mathrm{<span\; class="notranslate">\; the\; y</span>}}_{\mathrm{<span\; class="notranslate">\; 3</span>}}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; the\; y</span>}}_{\mathrm{<span\; class="notranslate">\; 4</span>}}}\end{array}\right.$

Step 52: Calculate the angle of the straight line formed by points 1', 2' and points 3' and 4' in the device coordinate system:

$\left\{\begin{array}{c}{\mathrm{<span\; class="notranslate">\; \&theta;</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}^{<span\; class="notranslate">\; \&prime;</span>}<span\; class="notranslate">\; =</span>{\mathrm{<span\; class="notranslate">\; the\; tan</span>}}^{<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; 1</span>}}\frac{{\mathrm{<span\; class="notranslate">\; the\; y</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}^{<span\; class="notranslate">\; \&prime;</span>}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; the\; y</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}}^{<span\; class="notranslate">\; \&prime;</span>}}{{\mathrm{<span\; class="notranslate">\; x</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}}^{<span\; class="notranslate">\; \&prime;</span>}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; x</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}^{<span\; class="notranslate">\; \&prime;</span>}}\\ {\mathrm{<span\; class="notranslate">\; \&theta;</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}}^{<span\; class="notranslate">\; \&prime;</span>}<span\; class="notranslate">\; =</span>{\mathrm{<span\; class="notranslate">\; the\; tan</span>}}^{<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; 1</span>}}\frac{{\mathrm{<span\; class="notranslate">\; x</span>}}_{\mathrm{<span\; class="notranslate">\; 3</span>}}^{<span\; class="notranslate">\; \&prime;</span>}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; x</span>}}_{\mathrm{<span\; class="notranslate">\; 4</span>}}^{<span\; class="notranslate">\; \&prime;</span>}}{{\mathrm{<span\; class="notranslate">\; the\; y</span>}}_{\mathrm{<span\; class="notranslate">\; 3</span>}}^{<span\; class="notranslate">\; \&prime;</span>}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; the\; y</span>}}_{\mathrm{<span\; class="notranslate">\; 4</span>}}^{<span\; class="notranslate">\; \&prime;</span>}}\end{array}\right.$

Step five and three: θ ₁ , θ ₂ , θ′ ₁ , θ′ ₂ should be approximately equal, and calculate the rotation angle of the fixed camera in the device coordinate system:

Step 6: Calculate the width of pixels in the x and y directions of the fixed camera according to the 8 moving position coordinates of the No. 1 patch head obtained in steps 2 and 4, that is, the scales of the fixed camera in the x and y directions are respectively recorded as w _{Fixed camera x} and w _{fixed camera y} , the unit is mm/pix;

Step 7: In step 3, after rotating 4 angles, calibrate the position coordinates of the center point of the nozzle head in the fixed camera, which are recorded as (x ₀ ,y ₀ ), (x ₉₀ ,y ₉₀ ), (x ₁₈₀ ,y ₁₈₀ ) and (x ₂₇₀ ,y ₂₇₀ ), according to these 4 sets of values, calculate the average position coordinates of the center of the calibrated nozzle head in the fixed camera coordinate system

Step 8: Put the position coordinates (x _device , y _device ) of the No. 1 patch head recorded in step 3 in the device coordinate system, the parameters and coordinate values obtained in steps 5, 6 and 7 into the following formula:

Calculate the coordinates of the optical center of the fixed camera in the device coordinate system (x _{fixed camera} , y _{fixed camera} ).

The technical effect of the present invention is that by correcting the coordinates, rotation angle and scale of the fixed camera, the deviation caused by manual installation to the detection process is compensated, the accuracy of the placement machine for the detection and positioning of the calibration point is improved, and the placement of the placement machine is improved. Effect.

Description of drawings:

Fig. 1 is a flowchart of the present invention;

Figure 2 is a schematic diagram of the lower surface of the calibration nozzle head;

Figure 3 shows the relative positional relationship between the fixed camera coordinate system and the device coordinate system;

Figure 4 is the image captured by the No. 1 flight camera when the No. 1 patch head is not equipped with a calibration nozzle head to detect whether there is a nozzle;

Figure 5 is the image captured by the No. 1 flying camera when the No. 1 patch head is installed with a calibrated nozzle head to detect whether there is a nozzle;

Figure 6 is the picture taken by the fixed camera when the nozzle head is calibrated and moved directly above the field of view of the fixed camera;

Figure 7 is an image of the center of the calibrated nozzle head in the field of view of the fixed camera after the nozzle head is calibrated in the equipment coordinate system and moved for a length of A/2 along the negative direction of the x-axis relative to the initial position;

Figure 8 is an image of the center of the calibrated nozzle head in the field of view of the fixed camera after the nozzle head is calibrated in the equipment coordinate system and moved for a length of A/2 along the positive direction of the x-axis relative to the initial position;

Figure 9 is an image of the center of the calibrated nozzle head in the field of view of the fixed camera after the nozzle head is calibrated in the equipment coordinate system and moved for a length of A/2 along the negative direction of the y-axis relative to the initial position;

Figure 10 is the image of the center of the calibrated nozzle head in the field of view of the fixed camera after the nozzle head is calibrated in the equipment coordinate system and moved for a length of A/2 along the positive direction of the y-axis relative to the initial position;

Figure 11 is the image in the field of view of the fixed camera when the calibration nozzle head is rotated to the 0° position, which is also the initial position in the second part;

Figure 12 is the image in the field of view of the fixed camera when the calibration nozzle head is rotated to the 90° position;

Figure 13 is the image in the field of view of the fixed camera when the calibration nozzle head is rotated to the 180° position;

Figure 14 is the image in the field of view of the fixed camera when the calibration nozzle head is rotated to the 270° position;

Figure 15 is the image of the center of the calibrated nozzle head in the field of view of the fixed camera after the nozzle head is calibrated in the equipment coordinate system and moved A/2 in the negative direction of the x-axis relative to the initial position;

Figure 16 is the image of the center of the calibrated nozzle head in the field of view of the fixed camera after the nozzle head is calibrated in the equipment coordinate system and moved for a length of A/2 along the positive direction of the x-axis relative to the initial position;

Figure 17 is the image of the center of the calibrated nozzle head in the field of view of the fixed camera after the nozzle head is calibrated in the equipment coordinate system and moved for a length of A/2 along the negative direction of the y-axis relative to the initial position;

Figure 18 is the image of the center of the calibrated nozzle head in the field of view of the fixed camera after the nozzle head is calibrated in the equipment coordinate system and moved for a length of A/2 along the positive direction of the y-axis relative to the initial position;

Figure 19 is a comparison of the coordinates and rotation angles before and after the correction of the fixed camera.

detailed description

Specific implementation mode one:

A calibration method for a fixed camera in this embodiment is implemented through the following steps:

Step 1: Initialize the camera settings of the placement machine, set the moving length A of the placement head when the fixed camera is corrected, the unit is mm, after the No. 1 placement head absorbs the calibration nozzle from the ANC nozzle slot, move to the top of the fixed camera field of view, and calibrate The target object is to calibrate the nozzle tip; ANC means the nozzle tip slot.

Step 2: Set the position of the No. 1 placement head in the equipment coordinate system as the initial position at this moment, first move the No. 1 placement head along the negative direction of the x-axis of the equipment coordinate system for a length of A/2, and then call the image detection program to obtain Calibrate the position coordinates of the center of the nozzle head in the fixed camera, which is recorded as D1(x ₁ , y ₁ ); then move the No. 1 placement head back to the initial position, and then move the No. 1 placement head along the positive direction of the x-axis of the equipment coordinate system Move the length of A/2, call the image detection program, and get the position coordinates of the center of the calibrated nozzle head in the fixed camera, which is recorded as D2 (x2, y2); move the No. 1 placement head back to the initial position, and then move the No. Move the length of A/2 in the negative direction of the y-axis of the equipment coordinate system, call the image detection program, and obtain the position coordinates of the center of the calibrated nozzle head in the fixed camera, which is recorded as D3 (x3, y3); then move the No. 1 patch head back to The initial position, and then move the No. 1 patch head along the positive direction of the y-axis of the equipment coordinate system for a length of A/2, call the image detection program, and obtain the position coordinates of the center of the calibrated nozzle head in the fixed camera, which is recorded as D4(x ₄ , y ₄ ), the unit of the position coordinate is mm.

The image detection program described in the present invention is a program that uses a machine learning algorithm and is used to recognize the position coordinates corresponding to the center of the nozzle head that appears therein through the input image, because this type of image detection program is commonly used in the prior art Means, such as adding parameter features to a training set composed of pictures for training, to obtain a classifier whose input is a picture and the output is a position coordinate. Since this is a conventional approach in the field of machine learning, the present invention does not describe the image detection procedure in detail.

"Invoking the image detection program" in the present invention should be understood as inputting the image captured by the fixed camera in the current state into the image detection program to obtain the identified position coordinates in the current state. "Current state" mainly refers to the current location.

Step 3: Move No. 1 placement head back to the initial position defined in step 2, rotate No. 1 placement head to the positions of 0°, 90°, 180° and 270° in the equipment coordinate system, and call the image detection program , according to the four angles of rotation, the position coordinates of the center point of the calibration nozzle head in the fixed camera are obtained, which are respectively recorded as (x ₀ , y ₀ ), (x ₉₀ , y ₉₀ ), (x ₁₈₀ , y ₁₈₀ ) and (x ₂₇₀ , y ₂₇₀ ), the units are pixels; and record the position coordinates (x _equipment , y _equipment ) of No. is the origin of the patch head coordinate system; the rotations described in the present invention are all counterclockwise rotations.

Step 4: Rotate the No. 1 patch head to the 360° position in the equipment coordinate system, which is the initial position defined in Step 2, and repeat Step 2 to obtain 4 sets of position coordinates D′ ₁ (x′ ₁ ,y′ ₁ ), D′ ₂ (x′ ₂ ,y′ ₂ ), D′ ₃ (x′ ₃ ,y′ ₃ ), D′ ₄ (x′ ₄ ,y′ ₄ ), the unit is pixel;

Step 5: Calculate and obtain 4 rotation angles θ ₁ , θ ₂ , θ′ ₁ and θ′ ₂ according to the 8 moving position coordinates of the patch head obtained in steps 2 and 4, and finally fix the camera coordinate system in the device coordinate system The rotation angle is The specific process is:

Step 51: Calculate the angle of the straight line formed by D ₁ , D ₂ and D ₃ , D ₄ in the image coordinate system:

$\left\{\begin{array}{c}{\mathrm{<span\; class="notranslate">\; \&theta;</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}<span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; t</span>}\mathrm{<span\; class="notranslate">\; a</span>}{\mathrm{<span\; class="notranslate">\; no</span>}}^{<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; 1</span>}}\frac{{\mathrm{<span\; class="notranslate">\; the\; y</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; the\; y</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}}}{{\mathrm{<span\; class="notranslate">\; x</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; x</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}}\\ {\mathrm{<span\; class="notranslate">\; \&theta;</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; =</span>{\mathrm{<span\; class="notranslate">\; the\; tan</span>}}^{<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; 1</span>}}\frac{{\mathrm{<span\; class="notranslate">\; x</span>}}_{\mathrm{<span\; class="notranslate">\; 3</span>}}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; x</span>}}_{\mathrm{<span\; class="notranslate">\; 4</span>}}}{{\mathrm{<span\; class="notranslate">\; the\; y</span>}}_{\mathrm{<span\; class="notranslate">\; 3</span>}}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; the\; y</span>}}_{\mathrm{<span\; class="notranslate">\; 4</span>}}}\end{array}\right.$

Step 52: Calculate the angle in the device coordinate system of the straight line formed by D′ ₁ , D′ ₂ and D′ ₃ , D′ ₄ :

$\left\{\begin{array}{c}{\mathrm{<span\; class="notranslate">\; \&theta;</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}^{<span\; class="notranslate">\; \&prime;</span>}<span\; class="notranslate">\; =</span>{\mathrm{<span\; class="notranslate">\; the\; tan</span>}}^{<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; 1</span>}}\frac{{\mathrm{<span\; class="notranslate">\; the\; y</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}^{<span\; class="notranslate">\; \&prime;</span>}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; the\; y</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}}^{<span\; class="notranslate">\; \&prime;</span>}}{{\mathrm{<span\; class="notranslate">\; x</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}}^{<span\; class="notranslate">\; \&prime;</span>}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; x</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}^{<span\; class="notranslate">\; \&prime;</span>}}\\ {\mathrm{<span\; class="notranslate">\; \&theta;</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}}^{<span\; class="notranslate">\; \&prime;</span>}<span\; class="notranslate">\; =</span>{\mathrm{<span\; class="notranslate">\; the\; tan</span>}}^{<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; 1</span>}}\frac{{\mathrm{<span\; class="notranslate">\; x</span>}}_{\mathrm{<span\; class="notranslate">\; 3</span>}}^{<span\; class="notranslate">\; \&prime;</span>}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; x</span>}}_{\mathrm{<span\; class="notranslate">\; 4</span>}}^{<span\; class="notranslate">\; \&prime;</span>}}{{\mathrm{<span\; class="notranslate">\; the\; y</span>}}_{\mathrm{<span\; class="notranslate">\; 3</span>}}^{<span\; class="notranslate">\; \&prime;</span>}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; the\; y</span>}}_{\mathrm{<span\; class="notranslate">\; 4</span>}}^{<span\; class="notranslate">\; \&prime;</span>}}\end{array}\right.$

Step five and three: θ ₁ , θ ₂ , θ′ ₁ , θ′ ₂ should be approximately equal, and calculate the rotation angle of the fixed camera in the device coordinate system:

Step 6: Calculate the width of pixels in the x and y directions of the fixed camera according to the 8 moving position coordinates of the No. 1 patch head obtained in steps 2 and 4, that is, the scales of the fixed camera in the x and y directions are respectively recorded as w _{Fixed camera x} and w _{fixed camera y} , the unit is mm/pix;

Step 7: In step 3, after rotating 4 angles, calibrate the position coordinates of the center point of the nozzle head in the fixed camera, which are recorded as (x ₀ ,y ₀ ), (x ₉₀ ,y ₉₀ ), (x ₁₈₀ ,y ₁₈₀ ) and (x ₂₇₀ ,y ₂₇₀ ), according to these 4 sets of values, calculate the average position coordinates of the center of the calibrated nozzle head in the fixed camera coordinate system

Step 8: Put the position coordinates (x _device , y _device ) of the No. 1 patch head recorded in step 3 in the device coordinate system, the parameters and coordinate values obtained in steps 5, 6 and 7 into the following formula:

Calculate the coordinates of the optical center of the fixed camera in the device coordinate system (x _{fixed camera} , y _{fixed camera} ).

Specific implementation mode two:

Different from the specific implementation mode 1, step 1 is specifically:

Step 11: Click the function button for patching the fixed camera, and read the moving length A of the fixed camera according to the prompt on the image interface;

Step 1 and 2: Place all suction nozzles according to the prompts of the graphical interface;

Step 13: Control the hardware to obtain the calibrated nozzle head from the place where the nozzle head is placed, and move the No. 1 mounter head directly above the center field of view of the fixed camera according to the prompt of the graphical interface of the placement machine;

Step 14: Control the No. 1 patch head to move above the center position of the fixed camera.

In the specific operation of this embodiment, it can be:

1) Click the <5. Fix Camera 1> button in the placement machine to prompt to place the nozzle. Read the moving length of the fixed camera from the "fixed camera" control in the "moving length" combo box, set it as A (A>0), and the unit is mm.

2) Click the Next button to place all nozzles. Prompt that the No. 1 patch head draws the calibration nozzle from the ANC.

3) Control the hardware to obtain the calibration tool from the ANC, the software interface displays and waits for "acquire the calibration tool", and the image part of the control image displays the image of the flying camera 1. Prompt to move the No. 1 patch head directly above the central field of view of the fixed camera.

4) Control the No. 1 placement head to move above the center position of the fixed camera, the image display window displays the image of the fixed camera, and the software interface displays the waiting movement process.

Other structures and parameters are the same as those in Embodiment 1.

Specific implementation mode three:

Different from the specific implementation mode 1 or 2, step 2 is specifically:

Step 21: Move the No. 1 placement head along the x-axis by -A/2, and set the coordinates of the No. 1 placement head relative to the optical center of the fixed camera at this time as D(x,y)=(-A/2,0), the unit mm;

Step 22: Input the image captured by the fixed camera at this time into the image detection program, and obtain the position D ₁ (x ₁ , y ₁ ) of the center point of the calibrated nozzle head in the fixed camera, and the unit is pixel;

Step 2 and 3: Move the No. 1 chip head along the x-axis by A. At this time, the coordinates of the No. 1 chip head relative to the optical center of the fixed camera are (A/2,0), and input the image captured by the fixed camera at this time into the image detection Program to get the position D ₂ (x ₂ ,y ₂ ) of the center of the circle in the fixed camera, unit pixel;

Step 24: Move the No. 1 chip head along the x-axis by -A/2, and move it along the y-axis by -A/2. At this time, the coordinates of the No. 1 chip head relative to the optical center of the fixed camera are (0, A/2), Input the image captured by the fixed camera at this time into the image detection program to obtain the position of the center of the circle in the fixed camera, which is recorded as D ₃ (x ₃ ,y ₃ ), and the unit is pixel;

Step 25: Move the No. 1 chip head along the y-axis by A. At this time, the coordinates of the No. 1 chip head relative to the optical center of the fixed camera are (0, A/2). Repeat steps 2 and 2 to obtain the position of the center of the circle in the fixed camera , denoted as D ₄ (x ₄ ,y ₄ ), unit pixel.

Other structures and parameters are the same as those in Embodiment 1 or Embodiment 2.

Specific implementation mode four:

The difference from one of the specific implementation modes 1 to 3 is that step 3 of this implementation mode is specifically:

Step 31: Move the No. 1 patch head back to the initial position defined in step 2, input the image captured by the fixed camera at this time into the image detection program, and obtain the position of the center of the calibrated nozzle head in the fixed camera, which is recorded as D ₀ (x ₀ ,y ₀ ), unit pixel;

Step 3 and 2: Input the images captured by the fixed camera when the No. 1 patch head is rotated to 90°, 180° and 270° respectively into the image detection program, and obtain the corresponding position of the center of the calibrated nozzle head in the fixed camera, which is recorded as ( x ₉₀ , y ₉₀ ), (x ₁₈₀ , y ₁₈₀ ), (x ₂₇₀ , y ₂₇₀ ), the unit is pixel, and record the position coordinates of No. 1 patch head in the device coordinate system as (x _device , y _device ), The unit is mm.

Other structures and parameters are the same as those in the first to third specific embodiments.

Specific implementation mode five:

The difference from one of the specific implementation modes 1 to 4 is that step 4 of this implementation mode is specifically:

Step 41: Rotate the No. 1 patch head to the 360° position, which is the initial position defined in step 2;

Step 4 and 2: Move the No. 1 chip head along the negative x axis by A/2, and set the coordinates of the No. 1 chip head relative to the optical center of the fixed camera at this time as D′(x′,y′)=(-A/2, 0), the unit is mm;

Step 43: Input the image captured by the fixed camera at this time into the image detection program to obtain the position D′ ₁ (x′ ₁ , y′ ₁ ) of the center point of the calibrated nozzle head in the fixed camera, and the unit is pixel;

Step 44: Move the No. 1 chip head along the x-axis in the positive direction A. At this time, the coordinates of the No. 1 chip head relative to the optical center of the fixed camera are (A/2,0), and input the image captured by the fixed camera at this time to The image detection program obtains the position of the center of the circle in the fixed camera, which is recorded as D′ ₂ (x′ ₂ , y′ ₂ ), unit pixel;

Step 4 and 5: Move the No. 1 chip head by A/2 along the negative direction of the x-axis, and move A/2 along the negative direction of the y-axis. At this time, the coordinates of the No. 1 chip head relative to the optical center of the fixed camera are D′(x′, y′)=(0,A/2), input the image captured by the fixed camera at this time into the image detection program, and obtain the position of the center of the circle in the fixed camera, denoted as D′ ₃ (x′ ₃ ,y′ ₃ ) , unit pixel;

Step 4 and 6: The patch head moves A in the positive direction along the y-axis. At this time, the coordinates of the No. 1 patch head relative to the optical center of the fixed camera are D′(x′,y′)=(0,A/2), and fix The image captured by the camera is input to the image detection program to obtain the position of the center of the circle in the fixed camera, which is denoted as D′ ₄ (x′ ₄ ,y′ ₄ ), and the unit is pixel.

At this time, the four positions are shown in Figure 3. Wherein, positions 1' and 2' are parallel to the y-axis, and positions 3' and 4' are parallel to the x-axis. Let the coordinates of the reference point in the image coordinate system at each position be (x′ _i , y′ _i ), i=1, 2, 3, 4.

Other structures and parameters are the same as those in the first to fourth specific embodiments.

Specific implementation method six:

The difference from one of the specific implementation modes 1 to 5 is that step 6 of this implementation mode is specifically:

Bring the 8 different moving position coordinates of No. 1 patch head obtained in Step 2 and Step 4 into the following formula for calculation.

Step 61: Fix the width of the pixel in the x direction of the camera as:

Step 62: Fix the width of the pixel in the y direction of the camera as:

Other structures and parameters are the same as those in the first to sixth specific embodiments.

Other structures and parameters are the same as one of the specific embodiments 1 to 5.

Specific implementation mode seven:

The difference from one of the specific implementation modes 1 to 6 is that step 7 of this implementation mode is specifically:

The 4 sets of rotation position coordinates (x ₀ , y ₀ ), (x ₉₀ , y ₉₀ ), (x ₁₈₀ , y ₁₈₀ ) and (x ₂₇₀ , y ₂₇₀ ) of the calibrated patch head center in the fixed camera in step 3 are taken with Enter the formula to calculate the average position coordinates of the center of the calibration patch head in the fixed camera coordinate system The specific calculation formula is as follows:

$\stackrel{<span\; class="notranslate">\; \&OverBar;</span>}{\mathrm{<span\; class="notranslate">\; x</span>}}<span\; class="notranslate">\; =</span>\underset{\mathrm{<span\; class="notranslate">\; i</span>}<span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; 0</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; 90</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; 180</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; 270</span>}}{<span\; class="notranslate">\; \&Sigma;</span>}{\mathrm{<span\; class="notranslate">\; x</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}}<span\; class="notranslate">\; /</span>\mathrm{<span\; class="notranslate">\; 4</span>}$

$\stackrel{<span\; class="notranslate">\; \&OverBar;</span>}{\mathrm{<span\; class="notranslate">\; the\; y</span>}}<span\; class="notranslate">\; =</span>\underset{\mathrm{<span\; class="notranslate">\; i</span>}<span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; 0</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; 90</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; 180</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; 270</span>}}{<span\; class="notranslate">\; \&Sigma;</span>}{\mathrm{<span\; class="notranslate">\; the\; y</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}}<span\; class="notranslate">\; /</span>\mathrm{<span\; class="notranslate">\; 4</span>}$

Other structures and parameters are the same as those in the first to sixth specific embodiments.

Specific implementation mode eight:

Different from one of the specific implementation modes 1 to 7, step 8 of this implementation mode is specifically:

Substitute the position coordinates (x _device , y _device ) of the No. 1 patch head recorded in step 3 in the device coordinate system, the rotation angle value, scale value and coordinate value calculated in step 5, step 6 and step 7 into the following formula:

Calculate the coordinates of the optical center of the fixed camera in the device coordinate system (x _{fixed camera} , y _{fixed camera} ).

Other structures and parameters are the same as one of the specific embodiments 1 to 7.

Specific implementation mode nine:

The difference from one of the specific embodiments 1 to 8 is that the moving length A of the patch head is 5 mm when the camera is fixed for correction in step 1.

Claims (9)

1. A fixed camera correction method is characterized in that it is realized in the following steps: Step 1: Initialize the camera settings of the placement machine, and set the moving length A of the placement head when the fixed camera is corrected. The unit is mm. The calibration nozzle tip mentioned above is the target object for calibration; Step 2: Set the position of the No. 1 placement head in the equipment coordinate system as the initial position at this moment, first move the No. 1 placement head along the negative direction of the x-axis of the equipment coordinate system for a length of A/2, and then call the image detection program to obtain Calibrate the position coordinates of the center of the nozzle head in the fixed camera, which is recorded as D1(x ₁ , y ₁ ); then move the No. 1 placement head back to the initial position, and then move the No. 1 placement head along the positive direction of the x-axis of the equipment coordinate system Move the length of A/2, call the image detection program, and get the position coordinates of the center of the calibrated nozzle head in the fixed camera, which is recorded as D2 (x2, y2); move the No. 1 placement head back to the initial position, and then move the No. Move the length of A/2 in the negative direction of the y-axis of the equipment coordinate system, call the image detection program, and obtain the position coordinates of the center of the calibrated nozzle head in the fixed camera, which is recorded as D3 (x3, y3); then move the No. 1 patch head back to The initial position, and then move the No. 1 patch head along the positive direction of the y-axis of the equipment coordinate system for a length of A/2, call the image detection program, and obtain the position coordinates of the center of the calibrated nozzle head in the fixed camera, which is recorded as D4(x ₄ , y ₄ ), the unit of the position coordinates is mm; Step 3: Move No. 1 placement head back to the initial position defined in step 2, rotate No. 1 placement head to the positions of 0°, 90°, 180° and 270° in the equipment coordinate system, and call the image detection program , according to the four angles of rotation, the position coordinates of the center point of the calibration nozzle head in the fixed camera are obtained, which are respectively recorded as (x ₀ , y ₀ ), (x ₉₀ , y ₉₀ ), (x ₁₈₀ , y ₁₈₀ ) and (x ₂₇₀ , y ₂₇₀ ), the units are pixels; and record the position coordinates (x _equipment , y _equipment ) of No. is the origin of the patch head coordinate system; Step 4: Rotate the No. 1 patch head to the 360° position in the equipment coordinate system, which is the initial position defined in Step 2, and repeat Step 2 to obtain 4 sets of position coordinates D′ ₁ (x′ ₁ ,y′ ₁ ), D′ ₂ (x′ ₂ ,y′ ₂ ), D′ ₃ (x′ ₃ ,y′ ₃ ), D′ ₄ (x′ ₄ ,y′ ₄ ), the unit is pixel; Step 5: Calculate and obtain 4 rotation angles θ ₁ , θ ₂ , θ′ ₁ and θ′ ₂ according to the 8 moving position coordinates of the patch head obtained in steps 2 and 4, and finally fix the camera coordinate system in the device coordinate system The rotation angle is The specific process is: Step 51: Calculate the angle of the straight line formed by D ₁ , D ₂ and D ₃ , D ₄ in the image coordinate system: $\left\{\begin{array}{c}{\mathrm{<span\; class="notranslate">\; \&theta;</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}<span\; class="notranslate">\; =</span>{\mathrm{<span\; class="notranslate">\; the\; tan</span>}}^{<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; 1</span>}}\frac{{\mathrm{<span\; class="notranslate">\; the\; y</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; the\; y</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}}}{{\mathrm{<span\; class="notranslate">\; x</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; x</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}}\\ {\mathrm{<span\; class="notranslate">\; \&theta;</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; =</span>{\mathrm{<span\; class="notranslate">\; the\; tan</span>}}^{<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; 1</span>}}\frac{{\mathrm{<span\; class="notranslate">\; x</span>}}_{\mathrm{<span\; class="notranslate">\; 3</span>}}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; x</span>}}_{\mathrm{<span\; class="notranslate">\; 4</span>}}}{{\mathrm{<span\; class="notranslate">\; the\; y</span>}}_{\mathrm{<span\; class="notranslate">\; 3</span>}}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; the\; y</span>}}_{\mathrm{<span\; class="notranslate">\; 4</span>}}}\end{array}\right.$ Step 52: Calculate the angle in the device coordinate system of the straight line formed by D′ ₁ , D′ ₂ and D′ ₃ , D′ ₄ : $\left\{\begin{array}{c}{\mathrm{<span\; class="notranslate">\; \&theta;</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}^{<span\; class="notranslate">\; \&prime;</span>}<span\; class="notranslate">\; =</span>{\mathrm{<span\; class="notranslate">\; the\; tan</span>}}^{<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; 1</span>}}\frac{{\mathrm{<span\; class="notranslate">\; the\; y</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}^{<span\; class="notranslate">\; \&prime;</span>}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; the\; y</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}}^{<span\; class="notranslate">\; \&prime;</span>}}{{\mathrm{<span\; class="notranslate">\; x</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}}^{<span\; class="notranslate">\; \&prime;</span>}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; x</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}^{<span\; class="notranslate">\; \&prime;</span>}}\\ {\mathrm{<span\; class="notranslate">\; \&theta;</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}}^{<span\; class="notranslate">\; \&prime;</span>}<span\; class="notranslate">\; =</span>{\mathrm{<span\; class="notranslate">\; the\; tan</span>}}^{<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; 1</span>}}\frac{{\mathrm{<span\; class="notranslate">\; x</span>}}_{\mathrm{<span\; class="notranslate">\; 3</span>}}^{<span\; class="notranslate">\; \&prime;</span>}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; x</span>}}_{\mathrm{<span\; class="notranslate">\; 4</span>}}^{<span\; class="notranslate">\; \&prime;</span>}}{{\mathrm{<span\; class="notranslate">\; the\; y</span>}}_{\mathrm{<span\; class="notranslate">\; 3</span>}}^{<span\; class="notranslate">\; \&prime;</span>}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; the\; y</span>}}_{\mathrm{<span\; class="notranslate">\; 4</span>}}^{<span\; class="notranslate">\; \&prime;</span>}}\end{array}\right.$ Step five and three: θ ₁ , θ ₂ , θ′ ₁ , θ′ ₂ should be approximately equal, and calculate the rotation angle of the fixed camera in the device coordinate system: Step 6: Calculate the width of pixels in the x and y directions of the fixed camera according to the 8 moving position coordinates of the No. 1 patch head obtained in steps 2 and 4, that is, the scales of the fixed camera in the x and y directions are respectively recorded as w _{Fixed camera x} and w _{fixed camera y} , the unit is mm/pix; Step 7: In step 3, after rotating 4 angles, calibrate the position coordinates of the center point of the nozzle head in the fixed camera, which are recorded as (x ₀ ,y ₀ ), (x ₉₀ ,y ₉₀ ), (x ₁₈₀ ,y ₁₈₀ ) and (x ₂₇₀ ,y ₂₇₀ ), according to these 4 sets of values, calculate the average position coordinates of the center of the calibrated nozzle head in the fixed camera coordinate system Step 8: Put the position coordinates (x _device , y _device ) of the No. 1 patch head recorded in step 3 in the device coordinate system, the parameters and coordinate values obtained in steps 5, 6 and 7 into the following formula: Calculate the coordinates of the optical center of the fixed camera in the device coordinate system (x _{fixed camera} , y _{fixed camera} ). 2. The fixed camera calibration method according to claim 1, characterized in that step 1 is specifically: Step 11: Click the function button for patching the fixed camera, and read the moving length A of the fixed camera according to the prompt on the image interface; Step 1 and 2: Place all suction nozzles according to the prompts of the graphical interface; Step 13: Control the hardware to obtain the calibrated nozzle head from the place where the nozzle head is placed, and move the No. 1 mounter head directly above the center field of view of the fixed camera according to the prompt of the graphical interface of the placement machine; Step 14: Control the No. 1 patch head to move above the center position of the fixed camera. 3. The fixed camera correction method according to claim 1, characterized in that step 2 is specifically: Step 21: Move the No. 1 placement head along the x-axis by -A/2, and set the coordinates of the No. 1 placement head relative to the optical center of the fixed camera at this time as D(x,y)=(-A/2,0), the unit mm; Step 22: Input the image captured by the fixed camera at this time into the image detection program, and obtain the position D ₁ (x ₁ , y ₁ ) of the center point of the calibrated nozzle head in the fixed camera, and the unit is pixel; Step 2 and 3: Move the No. 1 chip head along the x-axis by A. At this time, the coordinates of the No. 1 chip head relative to the optical center of the fixed camera are (A/2,0), and input the image captured by the fixed camera at this time into the image detection The program obtains the position D ₂ (x ₂ ,y ₂ ) of the center of the circle in the fixed camera, and the unit is pixel; Step 24: Move the No. 1 chip head along the x-axis by -A/2, and move it along the y-axis by -A/2. At this time, the coordinates of the No. 1 chip head relative to the optical center of the fixed camera are (0, A/2), Input the image captured by the fixed camera at this time into the image detection program to obtain the position of the center of the circle in the fixed camera, which is recorded as D ₃ (x ₃ ,y ₃ ), and the unit is pixel; Step 25: Move the No. 1 chip head along the y-axis by A. At this time, the coordinates of the No. 1 chip head relative to the optical center of the fixed camera are (0, A/2). Repeat steps 2 and 2 to obtain the position of the center of the circle in the fixed camera , denoted as D ₄ (x ₄ ,y ₄ ), the unit is pixel. 4. The fixed camera correction method according to claim 1, characterized in that step three is specifically: Step 31: Move the No. 1 patch head back to the initial position defined in step 2, input the image captured by the fixed camera at this time into the image detection program, and obtain the position of the center of the calibrated nozzle head in the fixed camera, which is recorded as D ₀ (x ₀ ,y ₀ ), the unit is pixel; Step 3 and 2: Input the images captured by the fixed camera when the No. 1 patch head is rotated to 90°, 180° and 270° respectively into the image detection program, and obtain the corresponding position of the center of the calibrated nozzle head in the fixed camera, which is recorded as ( x ₉₀ , y ₉₀ ), (x ₁₈₀ , y ₁₈₀ ), (x ₂₇₀ , y ₂₇₀ ), the unit is pixel, and record the position coordinates of No. 1 patch head in the device coordinate system as (x _device , y _device ), The unit is mm. 5. The fixed camera correction method according to claim 1, characterized in that step 4 is specifically: Step 41: Rotate the No. 1 patch head to the 360° position, which is the initial position defined in step 2; Step 4 and 2: Move the No. 1 chip head along the negative x axis by A/2, and set the coordinates of the No. 1 chip head relative to the optical center of the fixed camera at this time as D′(x′,y′)=(-A/2, 0), the unit is mm; Step 43: Input the image captured by the fixed camera at this time into the image detection program to obtain the position D′ ₁ (x′ ₁ , y′ ₁ ) of the center point of the calibrated nozzle head in the fixed camera, and the unit is pixel; Step 44: Move the No. 1 chip head along the x-axis in the positive direction A. At this time, the coordinates of the No. 1 chip head relative to the optical center of the fixed camera are (A/2,0), and input the image captured by the fixed camera at this time to The image detection program obtains the position of the center of the circle in the fixed camera, which is recorded as D′ ₂ (x′ ₂ , y′ ₂ ), and the unit is pixel; Step 4 and 5: Move the No. 1 chip head by A/2 along the negative direction of the x-axis, and move A/2 along the negative direction of the y-axis. At this time, the coordinates of the No. 1 chip head relative to the optical center of the fixed camera are D′(x′, y′)=(0,A/2), input the image captured by the fixed camera at this time into the image detection program, and obtain the position of the center of the circle in the fixed camera, denoted as D′ ₃ (x′ ₃ ,y′ ₃ ) , the unit is pixel; Step 4 and 6: The patch head moves A in the positive direction along the y-axis. At this time, the coordinates of the No. 1 patch head relative to the optical center of the fixed camera are D′(x′,y′)=(0,A/2), and fix The image captured by the camera is input to the image detection program to obtain the position of the center of the circle in the fixed camera, which is recorded as D′ ₄ (x′ ₄ ,y′ ₄ ), and the unit is pixel. 6. The fixed camera correction method according to claim 1, characterized in that step six is specifically: Bring the 8 different moving position coordinates of No. 1 patch head obtained in step 2 and step 4 into the following formula for calculation; Step 61: Fix the width of the pixel in the x direction of the camera as: Step 62: Fix the width of the pixel in the y direction of the camera as: 7. The fixed camera correction method according to claim 1, characterized in that step seven is specifically: The 4 sets of rotation position coordinates (x ₀ , y ₀ ), (x ₉₀ , y ₉₀ ), (x ₁₈₀ , y ₁₈₀ ) and (x ₂₇₀ , y ₂₇₀ ) of the calibrated patch head center in the fixed camera in step 3 are taken with Enter the formula to calculate the average position coordinates of the center of the calibration patch head in the fixed camera coordinate system The specific calculation formula is as follows: $\stackrel{<span\; class="notranslate">\; \&OverBar;</span>}{\mathrm{<span\; class="notranslate">\; x</span>}}<span\; class="notranslate">\; =</span>\underset{\mathrm{<span\; class="notranslate">\; i</span>}<span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; 0</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; 90</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; 180</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; 270</span>}}{<span\; class="notranslate">\; \&Sigma;</span>}{\mathrm{<span\; class="notranslate">\; x</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}}<span\; class="notranslate">\; /</span>\mathrm{<span\; class="notranslate">\; 4</span>}$ $\stackrel{<span\; class="notranslate">\; \&OverBar;</span>}{\mathrm{<span\; class="notranslate">\; the\; y</span>}}<span\; class="notranslate">\; =</span>\underset{\mathrm{<span\; class="notranslate">\; i</span>}<span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; 0</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; 90</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; 180</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; 270</span>}}{<span\; class="notranslate">\; \&Sigma;</span>}{\mathrm{<span\; class="notranslate">\; the\; y</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}}<span\; class="notranslate">\; /</span>\mathrm{<span\; class="notranslate">\; 4.</span>}$ 8. The fixed camera correction method according to claim 1, characterized in that step eight is specifically: Substitute the position coordinates (x _device , y _device ) of the No. 1 patch head recorded in step 3 in the device coordinate system, the rotation angle value, scale value and coordinate value calculated in step 5, step 6 and step 7 into the following formula: Calculate the coordinates of the optical center of the fixed camera in the device coordinate system (x _{fixed camera} , y _{fixed camera} ). 9. The fixed camera calibration method according to claim 1, characterized in that the moving length A of the patch head during the fixed camera calibration is 5 mm.