Material tray calibration method and calibration system

Abstract

The present invention relates to the field of image processing technology, and provides a correction method and correction system for a material tray. The correction method for the material tray comprises: in a material tray placement point array, determining a number of placement points as calibration points; obtaining the plane coordinates and height coordinates of each calibration point through a camera device and a distance measuring device respectively, to form a three-dimensional coordinate set of the calibration point; calculating the plane coordinates of each placement point according to the plane coordinates of some calibration points and the positional relationship between each placement point and the placement point array; calculating the height coordinates of each placement point through a Bezier surface according to the three-dimensional coordinate set and the positional relationship between each placement point and the placement point array; and obtaining a corrected three-dimensional coordinate set of the placement point array. The present invention realizes automatic correction of the three-dimensional direction of the material tray through a camera device and a distance measuring device, combined with the Bezier surface fitting principle, improves correction efficiency, improves correction accuracy, and overcomes the deformation and bending problem of the material tray.

Description

Technical Field

[0001] The present invention relates to the technical field of image processing, and in particular to a correction method and a correction system for a material tray. Background Art

[0002] In the production process of electronic products, electronic components are placed on trays. The trays will deform and bend as they are used, and they need to be corrected.

[0003] In the traditional calibration method, operators often manually calibrate the vertices of the material tray, and then use the calibrated vertices to expand and generate the coordinates of each position on the material tray.

[0004] However, in the above-mentioned traditional correction methods, the correction of vertices and the coordinates of each position generated by expansion are all based on the plane, and the height correction cannot be achieved. In actual production, due to the deformation and bending of the material tray, the height difference of the material placement at different positions is large, which affects the stable operation of the equipment. In addition, manual correction has a heavy manpower burden, is time-consuming, and has low efficiency, and it cannot guarantee the consistency of the correction effect of different operators.

[0005] It should be noted that the information disclosed in the above background technology section is only used to enhance the understanding of the background of the present invention, and therefore may include information that does not constitute the prior art known to ordinary technicians in the field. Summary of the invention

[0006] In view of this, the present invention provides a correction method and correction system for a material tray, which realizes automatic correction of the three-dimensional direction of the material tray through a camera device and a distance measuring device combined with the Bezier surface fitting principle, improves correction efficiency, improves correction accuracy, and overcomes the deformation and bending problem of the material tray.

[0007] One aspect of the present invention provides a material tray calibration method, comprising the steps of: determining a number of placement points in a placement point array of a material tray as calibration points; obtaining the plane coordinates and height coordinates of each of the calibration points through a camera device and a distance measuring device, respectively, to form a three-dimensional coordinate set of the calibration points; calculating the plane coordinates of each of the placement points according to the plane coordinates of some of the calibration points and the position of each placement point in the placement point array; calculating the height coordinate of each of the placement points through a Bezier surface according to the three-dimensional coordinate set and the positional relationship between each of the placement points and the placement point array; and obtaining a calibrated three-dimensional coordinate set of the placement point array.

[0008] In some embodiments, in the step of obtaining the plane coordinates and height coordinates of each of the calibration points, the step of obtaining the plane coordinates and height coordinates of a current calibration point includes: moving the camera device until the camera device is vertically aligned with the current calibration point, and reading the first plane coordinates of the camera device; according to the first plane coordinates, horizontally moving the ranging device until the ranging device is vertically aligned with the current calibration point, reading the measurement value of the ranging device, and generating the height coordinate of the current calibration point; according to the measurement value, moving the camera device again until the camera device is vertically aligned with the current calibration point and the current calibration point is located in the focal plane of the camera device, reading the second plane coordinates of the camera device, and generating the plane coordinates of the current calibration point.

[0009] In some embodiments, the camera device has a first coordinate system, the distance measuring device has a second coordinate system, and in the steps of horizontally moving the distance measuring device and moving the camera device again, the moving stroke is determined according to the conversion relationship between the first coordinate system and the second coordinate system.

[0010] In some embodiments, the placement point array is a rectangular array, the calibration points include a center point, a vertex, and a center point of each edge of the rectangular array, and the Bezier surface is a Bezier biquadratic surface.

[0011] In some embodiments, in the step of calculating the height coordinates of each of the placement points through a Bezier surface, the step of calculating the height coordinates of a current placement point includes: determining the row of the current placement point and the first vertex of the row, and calculating the weight of the current placement point in the row direction according to the ratio of the distance between the current placement point and the first vertex in the total distance of the row; determining the column of the current placement point and the second vertex of the column, and calculating the weight of the current placement point in the column direction according to the ratio of the distance between the current placement point and the second vertex in the total distance of the column; calculating the height coordinate of the current placement point according to the three-dimensional coordinate set, the row weight of the current placement point, and the column weight.

[0012] In some embodiments, the calculation formula of the row-wise weight Mu_X of the current placement point is:

[0013]

[0014] Wherein, x is the ratio of the distance between the current placement point and the first vertex to the total distance of the row;

[0015] The calculation formula of the column-wise weight Mu_Y of the current placement point is:

[0016]

[0017] Wherein, y is the ratio of the distance between the current placement point and the second vertex to the total distance of the column;

[0018] The calculation formula of the height coordinate Z of the current placement point is: Z = Mu_X T ·G·Mu_Y, G is the three-dimensional coordinate set.

[0019] In some embodiments, the step of calculating the plane coordinates of each of the placement points includes: calculating the plane coordinates of each of the placement points based on the plane coordinates of the vertices and the row and column positions of each of the placement points in the rectangular array; wherein each of the placement points in the rectangular array is evenly distributed in the plane direction.

[0020] In some embodiments, the imaging device is an industrial camera, and the distance measuring device is a laser rangefinder.

[0021] In some embodiments, in the step of obtaining the plane coordinates and the height coordinates of each calibration point, the plane coordinates and the height coordinates of each calibration point are obtained based on a three-dimensional coordinate system established with any of the calibration points as the origin.

[0022] Another aspect of the present invention provides a material tray correction system, comprising: a loading platform for placing the material tray; a mobile device for installing a camera device and a ranging device, the mobile device being movable relative to the loading platform; and a processor connected to the mobile device, the processor being configured to implement the correction method described in any of the above embodiments by executing executable instructions.

[0023] The beneficial effects of the present invention compared with the prior art include at least:

[0024] The plane coordinates and height coordinates of the calibration point are obtained through the camera device and the distance measuring device; the plane coordinates of the placement point are obtained according to the plane coordinates of the calibration point and the position of the placement point in the placement point array; the height coordinates of the placement point are calculated according to the three-dimensional coordinates of the calibration point and the positional relationship between the placement point and the placement point array through the Bezier surface fitting principle; thus, the corrected three-dimensional coordinate set of the placement point array is obtained according to the plane coordinates and height coordinates of the placement point, so as to realize the automatic correction of the three-dimensional direction of the material tray;

[0025] Compared with traditional correction methods, the correction method of the present invention can significantly improve correction efficiency, improve correction accuracy, improve equipment consistency, solve the height difference problem caused by deformation and bending of the material tray, and make the corrected placement point infinitely close to the actual point.

[0026] It is to be understood that the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] The accompanying drawings herein are incorporated into and constitute a part of the specification, illustrate embodiments consistent with the present invention, and together with the specification are used to explain the principles of the present invention. Obviously, the accompanying drawings described below are only some embodiments of the present invention, and for those of ordinary skill in the art, other accompanying drawings can be obtained based on these accompanying drawings without creative work.

[0028] Figure 1 A schematic structural diagram of a correction system for a material tray according to an embodiment of the present invention is shown;

[0029] Figure 2 A schematic diagram showing the steps of a method for calibrating a material tray in an embodiment of the present invention;

[0030] Figure 3 A schematic diagram showing the structure of a material tray in an embodiment of the present invention is shown;

[0031] Figure 4 A schematic diagram showing the steps of obtaining the plane coordinates and height coordinates of a current calibration point in an embodiment of the present invention is shown;

[0032] Figure 5 A schematic diagram showing the steps of calculating the height coordinates of a current object placement point in an embodiment of the present invention;

[0033] Figure 6 A schematic diagram showing the correction effect of the material tray in the embodiment of the present invention is shown. DETAILED DESCRIPTION

[0034] Example embodiments will now be described more fully with reference to the accompanying drawings. However, example embodiments can be implemented in a variety of forms and should not be construed as limited to the embodiments set forth herein. Instead, these embodiments are provided to make the present invention comprehensive and complete and to fully convey the concepts of the example embodiments to those skilled in the art.

[0035] In addition, the accompanying drawings are only schematic illustrations of the present invention and are not necessarily drawn to scale. The same reference numerals in the figures represent the same or similar parts, and their repeated description will be omitted. Some of the block diagrams shown in the accompanying drawings are functional entities and do not necessarily correspond to physically or logically independent entities. These functional entities can be implemented in software form, or implemented in one or more hardware modules or integrated circuits, or implemented in different networks and / or processor devices and / or microcontroller devices.

[0036] The step numbers in the following embodiments are only used to indicate different execution contents and do not strictly limit the execution order between the steps. The words "first", "second" and similar words used in the specific description do not indicate any order, quantity or importance, but are only used to distinguish different components. It should be noted that the features in the embodiments of the present invention and different embodiments can be combined with each other without conflict.

[0037] Figure 1 The main structure of the material tray calibration system in the embodiment is shown, and the positional relationship between the material tray, the camera device and the distance measuring device is shown. Figure 1 As shown, the calibration system includes a loading platform 11 for placing a material tray 12; a moving device 13 for installing a camera device 14 and a distance measuring device 15, and the moving device 13 can move relative to the loading platform 11; and a processor ( Figure 1 The processor is configured to execute executable instructions, control the camera device 14 and the distance measuring device 15, and realize automatic correction of the three-dimensional direction of the material tray 12 in combination with the Bezier surface fitting principle.

[0038] The moving device 13 may be composed of a mechanical arm. Under the control of the processor, the moving device 13 drives the camera device 14 and the distance measuring device 15 to move.

[0039] The camera device 14 may be an industrial camera, and the distance measuring device 15 may be a laser distance measuring device, but the present invention is not limited thereto. Figure 1 As shown in the figure, as long as it can be driven by the moving device 13 and move relative to the material tray 12 on the loading platform 11, the position coordinates of the specific position of the material tray 12 can be collected.

[0040] The processor is, for example, a CPU (central processing unit), which is electrically connected to the mobile device 13 and the camera device 14 and the distance measuring device 15 installed on the mobile device 13, so as to control the movement of the camera device 14 and the distance measuring device 15 through the mobile device 13, obtain the position coordinates collected by the mobile device 13 to control the camera device 14, perform calculations and processing, and realize the correction of the material tray 12.

[0041] Combine the following Figure 1 The correction system shown in the figure describes the correction method of the present invention in detail.

[0042] Figure 2 The main steps of the material tray calibration method in the embodiment are shown, referring to Figure 2 As shown, the calibration method of the material tray in this embodiment includes:

[0043] Step S210, in a material tray placement point array, a number of placement points are determined as calibration points. The calibration points are usually determined as some special positions on the material tray, such as vertices, center points, etc. At the same time, the position and number of the calibration points are determined according to the Bezier surface fitting requirements.

[0044] Figure 3 Shows the structure of the material tray, refer to Figure 3 As shown, the placement point array of the material tray 12 in this embodiment is a rectangular array of 9 rows (R1~R9) and 7 columns (C1~C7), and the calibration points include nine (31~39), which are respectively a center point, four vertices and center points of four sides of the rectangular array.

[0045] It should be noted that Figure 3 The layout of the placement point array on the material tray is only shown. In actual production, the number of rows and columns of the placement point array and the area size of each placement point can be flexibly adjusted according to production needs. Figure 3 Limits shown.

[0046] Subsequently, when the material tray 12 is subjected to surface fitting, that is, when the height coordinates of each placement point are calculated, the Bezier surface used is a Bezier biquadratic surface, so nine calibration points are required. In other embodiments, the position and number of calibration points can be flexibly changed according to different Bezier surface fitting requirements. For example, if a Bezier bicubic surface is used, sixteen calibration points are required.

[0047] After the calibration points are determined, electronic components can be placed at each calibration point. Each electronic component has a unique number to facilitate the collection of the coordinates of the subsequent calibration point positions.

[0048] Step S220, obtaining the plane coordinates and height coordinates of each calibration point through the camera device and the distance measuring device respectively, to form a three-dimensional coordinate set of the calibration point.

[0049] Figure 4 The specific steps of obtaining the plane coordinates and height coordinates of a current calibration point in the steps of obtaining the plane coordinates and height coordinates of each calibration point are shown, including: S220-2, moving the camera device until the camera device is vertically aligned with the current calibration point, and reading the first plane coordinates of the camera device; S220-4, according to the first plane coordinates, horizontally moving the distance measuring device until the distance measuring device is vertically aligned with the current calibration point, reading the measurement value of the distance measuring device, and generating the height coordinate of the current calibration point; S220-6, according to the measurement value, moving the camera device again until the camera device is vertically aligned with the current calibration point and the current calibration point is located in the focal plane of the camera device, reading the second plane coordinates of the camera device, and generating the plane coordinates of the current calibration point.

[0050] Before obtaining the plane coordinates and height coordinates of each calibration point, you can first take any calibration point as the origin, for example Figure 3 The vertex 37 shown in the figure is the origin, and a three-dimensional coordinate system of the material tray is established (the Z axis is perpendicular to the paper direction, not shown), so as to calculate and obtain the three-dimensional coordinates of each placement point based on the three-dimensional coordinate system of the material tray.

[0051] In addition, the camera device has a first coordinate system, the distance measuring device has a second coordinate system, and both the first coordinate system and the second coordinate system are three-dimensional coordinate systems. In the steps of horizontally moving the distance measuring device and moving the camera device again, the moving stroke is determined according to the conversion relationship between the first coordinate system and the second coordinate system.

[0052] Specifically, Figure 3 The vertex 33 shown in is the current calibration point. The process of obtaining the plane coordinates and height coordinates of the vertex 33 includes: first, moving the camera device so that the center point of the camera device is aligned with the vertex 33 in the vertical direction, and reading the first plane coordinates of the center point of the camera device at this time. The first plane coordinates are obtained based on the first coordinate system of the camera device. Secondly, the first plane coordinates are converted to the second coordinate system of the distance measuring device to obtain the movement stroke required for the center point of the distance measuring device to move horizontally to the vertex 33; then the distance measuring device is controlled to move horizontally until its center point is aligned with the vertex 33 in the vertical direction, and the measurement value of the distance measuring device at this time is read, and the measurement value is converted to the three-dimensional coordinate system of the material tray to generate the height coordinate Z of the vertex 33. 33 Afterwards, the focal plane height of the camera device can be calibrated according to the measurement value of the distance measuring device; the camera device is moved again until its center point is vertically aligned with the vertex 33, and the vertex 33 is located in the focal plane of the camera device. At this time, the second plane coordinates of the camera device are read again, and the second plane coordinates are converted into the three-dimensional coordinate system of the material tray to generate the precise plane coordinates of the vertex 33 (X 33 , Y 33 ). Thus, the three-dimensional coordinates P of vertex 33 are obtained. 33 =(X 33 , Y 33 , Z 33 ).

[0053] Finally, repeat the above steps to obtain the plane coordinates and height coordinates of each calibration point, forming a three-dimensional coordinate set of the calibration point, denoted as G:

[0054]

[0055] Step S230, calculating the plane coordinates of each placement point according to the plane coordinates of some calibration points and the position of each placement point in the placement point array.

[0056] When calculating the plane coordinates of each placement point, the plane coordinates of each placement point are calculated based on the plane coordinates of the four vertices and the row and column positions of each placement point in the rectangular array; wherein the placement points in the rectangular array are evenly distributed in the plane direction.

[0057] For example, based on the plane coordinates of the four vertices, the lengths of the four sides can be obtained first, that is, the lengths of the rows / columns can be obtained. Then, based on the position of each placement point on each side, the plane coordinates of each placement point on each side are obtained in combination with the length of the corresponding side and the plane coordinates of the vertices of the corresponding side, that is, the plane coordinates of the vertices of each row / column can be obtained. Furthermore, based on the position of each placement point in each row / column, the plane coordinates of the vertices of the corresponding row / column can be obtained.

[0058] Step S240, calculating the height coordinate of each placement point through the Bezier surface according to the three-dimensional coordinate set and the positional relationship between each placement point and the placement point array.

[0059] Figure 5 The specific steps of calculating the height coordinates of a current placement point in the steps of calculating the height coordinates of each placement point through a Bezier surface are shown, including: S240-2, determining the row where the current placement point is located and the first vertex of the row, and calculating the row weight of the current placement point according to the proportion of the distance between the current placement point and the first vertex in the total distance of the row; S240-4, determining the column where the current placement point is located and the second vertex of the column, and calculating the column weight of the current placement point according to the proportion of the distance between the current placement point and the second vertex in the total distance of the column; S240-6, calculating the height coordinate of the current placement point according to the three-dimensional coordinate set, the row weight of the current placement point, and the column weight.

[0060] The three-dimensional coordinate set is the three-dimensional coordinate set G of the nine calibration points obtained above. Through the three-dimensional coordinate set G of the nine calibration points, combined with the row and column position relationship of each placement point in the placement point matrix, a Bezier biquadratic surface is fitted as the working surface of the material tray.

[0061] Among them, the calculation formula of the row direction weight Mu_X of the current placement point is:

[0062]

[0063] x is the ratio of the distance between the current placement point and the first vertex to the total distance of the row;

[0064] The calculation formula of the column-wise weight Mu_Y of the current placement point is:

[0065]

[0066] y is the ratio of the distance between the current placement point and the second vertex to the total distance in the column;

[0067] The calculation formula of the height coordinate Z of the current placement point is: Z = Mu_X T ·G·Mu_Y.

[0068] Specifically, Figure 3 Taking the current placement point 30 as an example, the process of calculating the height coordinate of the current placement point 30 includes: firstly determining the row R4 where the current placement point 30 is located and the first vertex 30' of the row R4, and calculating the height coordinate of the current placement point 30 according to the ratio x of the length from the current placement point 30 to the first vertex 30' to the total length of the row R4. 30 , the row-wise weight Mu_X of the current placement point 30 can be calculated 30 Then determine the column C3 where the current placement point 30 is located and the second vertex 30″ of the column C3, and calculate the ratio y of the length from the current placement point 30 to the second vertex 30″ to the total length of the column C3. 30 , the column-wise weight Mu_Y of the current placement point 30 can be calculated 30 Finally, according to the three-dimensional coordinate set G and the weight Mu_X of the row direction of the current placement point 30 30 and the column-wise weight Mu_Y 30 , calculate the height coordinate Z of the current placement point 30 30 , Z 30 =Mu_X 30 T ·G·Mu_Y 30 .

[0069] Step S250, obtaining the three-dimensional coordinates of each placement point according to the plane coordinates and height coordinates of each placement point obtained above, and then obtaining a corrected three-dimensional coordinate set of the placement point array.

[0070] Figure 6 The correction effect of the material tray 12 is shown, wherein the height coordinates of nine calibration points are marked. Figure 3 and Figure 6As shown, through correction, it is found that the height coordinate of calibration point 31 is 0.33, indicating that the height of calibration point 31 has increased by 0.33mm relative to the original height; the height coordinate of calibration point 32 is 0.78, indicating that the height of calibration point 32 has increased by 0.78mm relative to the original height; the height coordinate of calibration point 33 is 0.52, indicating that the height of calibration point 33 has increased by 0.52mm relative to the original height; the height coordinate of calibration point 34 is -0.38, indicating that the height of calibration point 34 has decreased by 0.38mm relative to the original height; the height coordinate of calibration point 35 is -0.21, indicating The position height of calibration point 35 is reduced by 0.21mm relative to the original height; the height coordinate of calibration point 36 is -0.35, indicating that the position height of calibration point 36 is reduced by 0.35mm relative to the original height; the height coordinate of calibration point 37 is -0.99, indicating that the position height of calibration point 37 is reduced by 0.99mm relative to the original height; the height coordinate of calibration point 38 is -0.70, indicating that the position height of calibration point 38 is reduced by 0.70mm relative to the original height; the height coordinate of calibration point 39 is -0.79, indicating that the position height of calibration point 39 is reduced by 0.79mm relative to the original height.

[0071] The correction effect of the overall placement point array shows that the placement points in area 610 are higher due to the deformation and bending of the material tray 12, and the placement points in area 620 are lower due to the deformation and bending of the material tray 12. Therefore, after the correction, when placing materials at a certain placement point later, the materials can be accurately placed according to the corrected three-dimensional coordinates, especially the corrected height coordinates.

[0072] In summary, the correction method and correction system of the material tray of the present invention realizes automatic correction of the three-dimensional direction of the material tray by using a camera device and a distance measuring device combined with the Bezier surface fitting principle. Compared with the traditional correction method, it can achieve the following advantages:

[0073] First, the calibration efficiency of the material tray is improved. In the traditional calibration method, it takes more than 30 minutes for operators to manually calibrate the material tray; using the calibration method and calibration system of the material tray of the present invention, the automatic calibration of the material tray can be completed within 10 minutes.

[0074] Second, improve the calibration accuracy of the material tray. By using machine vision and laser ranging instead of human eye observation, the calibration accuracy is significantly improved compared to manual calibration.

[0075] Third, improve equipment consistency. Automatic correction can overcome the differences in individual skill levels among operators, thereby improving equipment consistency.

[0076] Fourth, it reduces the need for operators. The equipment automatically performs identification and position calculation, which reduces the operator's arm operation and reduces the visual skill requirements.

[0077] Fifth, Bezier surface fitting is performed through multiple calibration points to solve the height difference problem caused by the deformation and bending of the material tray, so that the corrected placement point is infinitely close to the actual point.

[0078] The above contents are further detailed descriptions of the present invention in combination with specific preferred embodiments, and it cannot be determined that the specific implementation of the present invention is limited to these descriptions. For ordinary technicians in the technical field to which the present invention belongs, several simple deductions or substitutions can be made without departing from the concept of the present invention, which should be regarded as falling within the protection scope of the present invention.

Claims

1. A method for calibrating a material tray, characterized in that: Includes steps: In an array of placement points of a material tray, a plurality of placement points are determined as calibration points; Obtaining the plane coordinates and height coordinates of each calibration point through a camera device and a distance measuring device respectively, to form a three-dimensional coordinate set of the calibration point; Calculate the plane coordinates of each placement point according to the plane coordinates of some of the calibration points and the position of each placement point in the placement point array; Calculating the height coordinate of each placement point through a Bezier surface according to the three-dimensional coordinate set and the positional relationship between each placement point and the placement point array; Wherein, the placement point array is a rectangular array, the calibration points include the center point, the vertices and the center point of each edge of the rectangular array, and the Bezier surface is a Bezier biquadratic surface; in the step of calculating the height coordinate of each placement point through the Bezier surface, the step of calculating the height coordinate of a current placement point includes: determining the row where the current placement point is located and the first vertex of the row, and calculating the row weight of the current placement point according to the proportion of the distance between the current placement point and the first vertex in the total distance of the row; determining the column where the current placement point is located and the second vertex of the column, and calculating the column weight of the current placement point according to the proportion of the distance between the current placement point and the second vertex in the total distance of the column; calculating the height coordinate of the current placement point according to the three-dimensional coordinate set, the row weight of the current placement point and the column weight; and A corrected three-dimensional coordinate set of the object placement point array is obtained.

2. The calibration method according to claim 1, characterized in that: In the step of obtaining the plane coordinates and the height coordinates of each calibration point, the step of obtaining the plane coordinates and the height coordinates of a current calibration point comprises: Moving the camera device until the camera device is vertically aligned with the current calibration point, and reading the first plane coordinates of the camera device; According to the first plane coordinates, horizontally move the distance measuring device until the distance measuring device is vertically aligned with the current calibration point, read the measurement value of the distance measuring device, and generate the height coordinate of the current calibration point; According to the measurement value, the camera device is moved again until the camera device is vertically aligned with the current calibration point and the current calibration point is located in the focal plane of the camera device, the second plane coordinates of the camera device are read, and the plane coordinates of the current calibration point are generated.

3. The calibration method according to claim 2, characterized in that: The camera device has a first coordinate system, the distance measuring device has a second coordinate system, and in the steps of horizontally moving the distance measuring device and moving the camera device again, the moving stroke is determined according to the conversion relationship between the first coordinate system and the second coordinate system.

4. The calibration method according to claim 1, wherein: The calculation formula of the row-wise weight Mu_X of the current placement point is: Wherein, x is the ratio of the distance between the current placement point and the first vertex to the total distance of the row; The calculation formula of the column-wise weight Mu_Y of the current placement point is: Wherein, y is the ratio of the distance between the current placement point and the second vertex to the total distance of the column; The calculation formula of the height coordinate Z of the current placement point is: Z = Mu_X T ·G·Mu_Y, G is the three-dimensional coordinate set.

5. The calibration method according to claim 1, wherein: The step of calculating the plane coordinates of each of the placement points comprises: Calculate the plane coordinates of each of the placement points according to the plane coordinates of the vertices and the row and column positions of each of the placement points in the rectangular array; Wherein, each of the placement points in the rectangular array is evenly distributed in the plane direction.

6. The calibration method according to claim 1, wherein: The imaging device is an industrial camera, and the distance measuring device is a laser distance meter.

7. The calibration method according to any one of claims 1 to 6, characterized in that: In the step of obtaining the plane coordinates and the height coordinates of each calibration point, the plane coordinates and the height coordinates of each calibration point are obtained based on a three-dimensional coordinate system established with any one of the calibration points as the origin.

8. A material tray calibration system, characterized in that: include: Loading platform for placing material trays; A moving device, used to install a camera device and a distance measuring device, and the moving device can move relative to the loading platform; as well as A processor is connected to the mobile device, and the processor is configured to implement the correction method according to any one of claims 1 to 7 by executing executable instructions.

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