A fully automatic coating line for automobile parts and control method thereof

Abstract

The present invention relates to the field of automobile parts coating, and in particular to a fully automatic coating line for automobile parts and a control method thereof. The method first obtains the gloss data of different measuring positions in the current spraying area and each historical spraying area of ​​the automobile parts in the current coating round, and the height data of different measuring points in the current spraying area, analyzes the distribution difference of the gloss data of each measuring position in the current spraying area and the historical spraying area, obtains the gloss effect difference of the current spraying area, obtains the concave-convex characteristic value of the current spraying area according to the distribution of the height data of the measuring points in the current spraying area, and then adjusts the spray pressure to obtain the real-time spray pressure of the current spraying area, and coats the automobile parts by using the spraying equipment with real-time spray pressure, and judges whether to coat the coated automobile parts for the next round. The present invention can improve the efficiency of automobile parts coating.

Description

Technical Field

[0001] The invention relates to the field of automobile parts coating, and in particular to a full-automatic automobile parts coating line and a control method thereof. Background Art

[0002] The fully automatic coating line for automobile parts is a highly efficient industrial equipment used for coating automobile parts. Its main function is to spray paint and other processes on the surface of automobile parts through automated equipment and systems to improve the anti-corrosion performance, aesthetics and other characteristics of the parts.

[0003] In the related art, a fixed spraying pressure is usually used on the coating line to spray paint on the surface of automobile parts. However, due to the presence of concave and convex areas on the surface of automobile parts, the deposition thickness of the paint in the concave and convex areas is different. When the existing method uses a fixed spraying pressure for coating, the gloss uniformity of different areas of the painted automobile parts is poor, so more rounds of coating are required to achieve the desired effect, reducing the efficiency of coating automobile parts. Summary of the invention

[0004] In order to solve the technical problem that the existing method uses a fixed spraying pressure for coating, which leads to poor uniformity of the gloss of the coated automobile parts and reduces the efficiency of coating the automobile parts, the purpose of the present invention is to provide an automatic coating line for automobile parts and a control method thereof. The technical scheme adopted is as follows:

[0005] The present invention proposes a control method for a fully automatic coating line for automobile parts, the method comprising:

[0006] Obtain gloss data of different measuring positions in the current spraying area and each historical spraying area of ​​the automobile parts in the current painting round, and height data of different measuring points in the current spraying area;

[0007] Taking the current spraying area or any historical spraying area as the target spraying area, obtaining the gloss effect value of the target spraying area according to the distribution of glossiness data of all measurement positions in the target spraying area; obtaining the gloss effect difference of the current spraying area according to the difference of the gloss effect value between the current spraying area and the historical spraying area;

[0008] According to the distribution of height data of different measuring points in the current spraying area, the concave-convex characteristic value of the current spraying area is obtained; based on the gloss effect difference of the current spraying area and the concave-convex characteristic value, the rated spray pressure of the spraying equipment is adjusted to obtain the real-time spray pressure of the spraying equipment in the current spraying area; the current spraying area is painted by the spraying equipment using the real-time spray pressure, and the current spraying area after painting is used as the historical spraying area, and the next non-historical spraying area is used as the new current spraying area, the real-time spray pressure of the spraying equipment in the new current spraying area is updated, and the new current spraying area is painted until the painting of the automobile parts is completed, so as to obtain the painted automobile parts of the current painting round;

[0009] Determine whether to proceed with the next round of painting on the painted automobile parts.

[0010] Further, obtaining the gloss effect value of the target spraying area includes:

[0011] Obtaining the gloss uniformity of the target spraying area according to the difference of the gloss data at any two measurement positions in the target spraying area;

[0012] Obtaining the overall glossiness of the target spraying area according to the overall distribution level of the glossiness data at all measurement positions in the target spraying area;

[0013] The gloss uniformity and the overall glossiness of the target spraying area are combined to obtain a gloss effect value of the target spraying area.

[0014] Furthermore, obtaining the gloss uniformity of the target spraying area includes:

[0015] Taking any two measurement positions in the target spraying area as a measurement position group, and taking the absolute value of the difference between the gloss data of the two measurement positions in each measurement position group as the initial gloss difference value of each measurement position group;

[0016] The average values ​​of the initial gloss difference values ​​of all measurement position groups are negatively correlated to obtain the gloss uniformity of the target spraying area.

[0017] Furthermore, obtaining the gloss effect difference of the current spraying area includes:

[0018] The average of the gloss effect values ​​of all historical spraying areas is taken as the historical overall effect value;

[0019] The difference between the gloss effect value of the current spraying area and the historical overall effect value is normalized to serve as the gloss effect difference of the current spraying area.

[0020] Further, obtaining the concave-convex characteristic value of the current spraying area includes:

[0021] The maximum value of all height data of the current spraying area is used as the numerator, the minimum value of all height data of the current spraying area is used as the denominator, and the ratio is used as the first concave-convex parameter of the current spraying area;

[0022] Performing curve fitting on the height data of all measuring points in the current spraying area to obtain a height fitting curve of the current spraying area; connecting two end points of the height fitting curve to obtain a reference line segment of the current spraying area;

[0023] The area enclosed by the height fitting curve and the reference line segment is used as a reference area, the reference area below the reference line segment is used as a lower reference area, and the reference area above the reference line segment is used as an upper reference area; the difference in area between the lower reference area and the upper reference area is used as a second concave-convex parameter of the current spraying area;

[0024] The product value of the first concavo-convex parameter and the second concavo-convex parameter of the current spraying area is normalized to obtain the concavo-convex characteristic value of the current spraying area.

[0025] Furthermore, obtaining the real-time spray pressure of the spraying equipment in the current spraying area includes:

[0026] Normalizing the gloss effect difference and the sum of the concave-convex characteristic values ​​of the current spraying area to obtain a spray pressure adjustment coefficient of the current spraying area;

[0027] The difference between the value 1 and the spray pressure adjustment coefficient is used as the adjustment degree of the current spraying area, and the product of the adjustment degree and the rated spray pressure of the spraying equipment is used as the real-time spray pressure of the spraying equipment in the current spraying area.

[0028] Furthermore, the determination of whether to perform the next round of painting on the painted automobile parts includes:

[0029] According to the difference between the real-time spray pressure and the rated spray pressure of the historical spraying area of ​​the painted automobile part and the distribution of the gloss effect values ​​of all historical spraying areas, it is determined whether to perform the next round of painting on the painted automobile part.

[0030] Further, judging whether to perform the next round of painting on the painted automobile parts according to the difference between the real-time spray pressure and the rated spray pressure of the historical spraying area of ​​the painted automobile parts and the distribution of the gloss effect values ​​of all historical spraying areas includes:

[0031] Analyzing the discrete degree of the gloss effect value of all historical spraying areas of the painted automobile parts to obtain a first painting evaluation value of the current painting round;

[0032] The absolute value of the difference between the real-time spray pressure and the rated spray pressure of each historical spraying area of ​​the painted automobile parts is used as the spray pressure change of the spraying equipment in each historical spraying area; the average value of the spray pressure change of all historical spraying areas is used as the second painting evaluation value of the current painting round;

[0033] The first coating evaluation value and the second coating evaluation value are integrated and normalized to obtain a comprehensive coating evaluation value of the current coating round;

[0034] Based on the comprehensive painting evaluation value, it is determined whether to perform the next round of painting on the painted automobile parts.

[0035] Further, judging whether to perform the next round of painting on the painted automobile parts based on the comprehensive painting evaluation value includes:

[0036] If the coating effect evaluation value is less than a preset evaluation threshold, the next round of coating will not be performed on the coated automobile parts; otherwise, the next round of coating will continue to be performed on the coated automobile parts.

[0037] The present invention also proposes a fully automatic coating line for automobile parts, including a spraying device. The coating line also includes a spraying control module for controlling the spraying equipment, a gloss meter for collecting gloss data for each spraying area of ​​the automobile parts, and a surface profiler for collecting height data of each spraying area. The spraying control module samples and connects the gloss meter and the surface profiler to obtain gloss data and height data, and processes the gloss data and height data to implement any one of the steps of the method for controlling a fully automatic coating line for automobile parts.

[0038] The present invention has the following beneficial effects:

[0039] The present invention takes into account that when a coating line with a fixed spraying pressure is used to coat automobile parts, the gloss uniformity of the automobile parts after coating will be poor, so that more rounds of coating are required to achieve the expected effect, reducing the efficiency of coating automobile parts. Therefore, the present invention first obtains the gloss data of different measuring positions in the current spraying area and each historical spraying area of ​​the automobile parts in the current coating round, as well as the height data of different measuring points in the current spraying area. Considering that in the process of coating different spraying areas of automobile parts, it is necessary to ensure that the gloss uniformity of each spraying area after coating is high, the gloss effect value is firstly obtained to reflect the gloss characteristics of the current spraying area and each historical spraying area of ​​the automobile parts, so as to provide a data basis for the subsequent analysis of the difference in gloss characteristics of different spraying areas and the evaluation of the coating effect of automobile parts, and then the difference in gloss characteristics between the current spraying area and the historical spraying area is reflected by the obtained gloss effect difference. Subsequently, the gloss effect difference can be used to reflect the difference in gloss characteristics between the current spraying area and the historical spraying area. The spray pressure of the spraying equipment is adjusted so that the gloss characteristics of the current spraying area after painting are more similar to those of the historical spraying area. Considering that the surface conditions of automobile parts are relatively complex, there are concave areas and convex areas, and the deposition thickness of the paint in the concave areas and the convex areas is different, which will also lead to uneven gloss of the concave areas and the convex areas after painting. Therefore, the present invention reflects the concave and convex conditions of the surface of the current spraying area through the acquired concave and convex feature values. Subsequently, the rated spray pressure of the spraying equipment can be adjusted in combination with the concave and convex feature values ​​and the gloss effect difference of the current spraying area, and the current spraying area is painted using the real-time spray pressure, so as to complete the painting of the entire automobile parts of the current painting round, so that the subsequent painting of automobile parts can achieve the expected effect faster. Since it is usually necessary to paint automobile parts for multiple rounds in order to achieve the expected painting effect, the present invention evaluates the painting effect of the current painting round and determines whether to carry out the next round of painting, thereby improving the efficiency of painting automobile parts. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] In order to more clearly illustrate the technical solutions and advantages in the embodiments of the present invention or the prior art, the drawings required for use in the embodiments or the prior art descriptions are briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0041] Figure 1 A flow chart of a method for controlling a fully automatic coating line for automobile parts provided by one embodiment of the present invention;

[0042] Figure 2 A flow chart of a method for obtaining a gloss effect value of a target spraying area provided by one embodiment of the present invention;

[0043] Figure 3 A schematic diagram of an upper reference area and a lower reference area provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0044] In order to further explain the technical means and effects adopted by the present invention to achieve the predetermined invention purpose, the following is a detailed description of a fully automatic coating line for automobile parts and its control method according to the present invention, its specific implementation method, structure, features and effects, in conjunction with the accompanying drawings and preferred embodiments. In the following description, different "one embodiment" or "another embodiment" does not necessarily refer to the same embodiment. In addition, specific features, structures or characteristics in one or more embodiments may be combined in any suitable form.

[0045] Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs.

[0046] The specific scheme of a fully automatic coating line for automobile parts and a control method thereof provided by the present invention is described in detail below with reference to the accompanying drawings.

[0047] See also Figure 1 , which shows a flow chart of a method for controlling a fully automatic coating line for automobile parts provided by an embodiment of the present invention, the method comprising:

[0048] Step S1: Obtain gloss data of different measuring positions in the current spraying area and each historical spraying area of ​​the automobile part in the current painting round, as well as height data of different measuring points in the current spraying area.

[0049] The automatic coating line for automobile parts is generally divided into a pretreatment system, an automatic spraying system, a drying and curing system, a conveying system, and a quality inspection system. The automation and intelligence of automobile parts coating are realized through the cooperation and coordination between different systems. Among them, the automatic spraying system is the core part of the coating line. The surface of automobile parts is coated with spraying equipment such as automatic spray guns or spraying robots. In order to make the painted automobile parts achieve the expected gloss effect, it is usually necessary to perform multiple rounds of coating on the automobile parts. At the same time, due to the limited coating range of the spraying equipment, the area sprayed each time is relatively small relative to the entire automobile parts. In a certain round of coating, the spraying equipment needs to be moved multiple times. Therefore, the existing coating line usually contains a spray control module to control the movement of the spraying equipment and control the spraying equipment to perform coating at a fixed spray pressure, thereby completing the coating of the entire automobile parts.

[0050] The embodiment of the present invention first uses a gloss meter installed on a spraying device to collect gloss data of different measurement positions in a current spraying area and each historical spraying area of ​​an automobile part in a current painting round, wherein the measurement positions in the current spraying area or each historical spraying area are evenly distributed.

[0051] At the same time, a surface profiler installed on the spraying equipment is used to collect height data of different measuring points in the current spraying area, wherein the process of collecting height data by the surface profiler is as follows: first, two endpoints with the farthest distance are selected on the edge of the current spraying area, one endpoint is selected as the starting endpoint, and the other endpoint is selected as the ending endpoint, and then the height data of each measuring point on the surface of the current spraying area is collected along the direction of the line connecting the two endpoints. At this time, each measuring point can be represented by the horizontal distance from the measuring point to the starting endpoint, and in an embodiment of the present invention, the spraying control module is connected to the gloss meter and the surface profiler by wired or wireless connection to obtain the gloss data collected by the gloss meter and the height data obtained by the surface profiler. Subsequently, the obtained gloss data and height data can be processed by the spraying control module to adjust the spray pressure of the spraying equipment, and in the process of multiple rounds of painting of automobile parts, it is determined whether to perform the next round of painting on the painted automobile parts.

[0052] It should be noted that the current spraying area refers to the spraying area that has not been painted and corresponds to the spraying equipment at the current position in the current painting round. The spray pressure of the spraying equipment in the current spraying area needs to be adjusted later to complete the painting process of the current spraying area. The historical spraying area refers to the spraying area that has been painted by the spraying equipment before the current spraying area in the current painting round. In order to ensure the accuracy of subsequent analysis, during the multiple movements of the spraying equipment, it is necessary to ensure that the corresponding spraying areas after each movement of the spraying equipment do not overlap with each other. At the same time, if the current spraying area is the area corresponding to the spraying equipment when the spraying equipment starts painting in the current painting round, there is no historical spraying area before the current spraying area. At this time, the current spraying area can be directly painted by using the spraying equipment with a rated spray pressure, wherein the rated spray pressure of the spraying equipment is a known value, which is related to the spraying pressure equipment used and is set by the manufacturer during the production process of the spraying equipment.

[0053] Step S2: Take the current spraying area or any historical spraying area as the target spraying area, and obtain the gloss effect value of the target spraying area according to the distribution of gloss data of all measurement positions in the target spraying area; obtain the gloss effect difference of the current spraying area according to the difference in gloss effect value between the current spraying area and the historical spraying area.

[0054] In the process of painting different spraying areas of automobile parts, it is necessary to ensure that the gloss uniformity of the surface of each spraying area after painting is high. Therefore, it is necessary to analyze the surface gloss characteristics of the current spraying area and each historical spraying area. First, the current spraying area or any historical spraying area is taken as the target spraying area. Considering that the gloss characteristics of the surface of the target spraying area can be reflected by the gloss data of each measuring position, the overall level of the gloss data of the target spraying area is large, and the gloss data are relatively close, which means that the gloss characteristics of the surface of the target spraying area are better. Therefore, the distribution of gloss data of all measuring positions in the target spraying area can be analyzed. The gloss effect value obtained reflects the gloss characteristics of the current spraying area and each historical spraying area of ​​the automobile parts, which provides a data basis for the subsequent analysis of the differences in gloss characteristics of different spraying areas and the evaluation of the painting effect of automobile parts.

[0055] Preferably, in one embodiment of the present invention, the method for obtaining the gloss effect value of the target spraying area specifically includes:

[0056] See also Figure 2 , which shows a flow chart of a method for obtaining a gloss effect value of a target spraying area provided by an embodiment of the present invention.

[0057] Step S201: Obtaining the gloss uniformity of the target spraying area according to the difference in gloss data between any two measurement positions in the target spraying area.

[0058] The smaller the difference in gloss data at each measuring position in the target spraying area, the more uniform the gloss effect at each measuring position in the target spraying area, and further the better the gloss characteristic effect of the target spraying area. Therefore, the difference in gloss data at any two measuring positions in the target spraying area can be analyzed to obtain the gloss uniformity of the target spraying area, providing a data basis for the subsequent accurate calculation of the gloss effect value of the target spraying area.

[0059] Preferably, in one embodiment of the present invention, the method for obtaining the gloss uniformity of the target spraying area specifically includes:

[0060] Any two measurement positions in the target spraying area are taken as a measurement position group, and the absolute value of the difference between the gloss data of the two measurement positions in each measurement position group is taken as the initial gloss difference value of each measurement position group. The smaller the initial gloss difference value is, the more similar the gloss characteristics of the two measurement positions in the measurement position group are. Then, the average values ​​of the initial gloss difference values ​​of all measurement position groups can be negatively correlated and mapped to obtain the gloss uniformity of the target spraying area.

[0061] As an example, in one embodiment of the present invention, the expression of the gloss uniformity of the target spraying area can be specifically, for example, as follows:

[0062]

[0063] in, Indicates the gloss uniformity of the target spraying area; and Respectively represent the target spraying area gloss data of two measurement positions in a measurement position group; Indicates Initial gloss difference values ​​for groups of measurement positions; The number of measurement position groups representing the target spraying area; Represents the preset adjustment parameter, which is used to prevent the denominator from being 0. The value range of the preset adjustment parameter is In one embodiment of the present invention, Set to 0.01, The specific value of can also be set by the implementer according to the specific implementation scenario and is not limited here.

[0064] It should be noted that in other embodiments of the present invention, negative correlation mapping may be achieved through other basic mathematical operations, which will not be elaborated herein.

[0065] Step S202: obtaining the overall glossiness of the target spraying area according to the overall distribution level of the glossiness data of all measurement positions in the target spraying area.

[0066] The higher the overall level of gloss data of all measuring positions in the target spraying area, the brighter the surface of the target spraying area, and thus the better the gloss characteristic effect of the surface of the target spraying area. Therefore, the overall gloss of the target spraying area can be obtained according to the overall distribution level of gloss data of all measuring positions in the target spraying area, providing a data basis for the subsequent accurate calculation of the gloss effect value of the target spraying area.

[0067] In one embodiment of the present invention, the average value of the glossiness data of all the measuring positions in the target spraying area may be taken as the overall glossiness of the target spraying area.

[0068] Step S203: The gloss uniformity and overall glossiness of the target spraying area are integrated to obtain a gloss effect value of the target spraying area.

[0069] From the above analysis, it can be seen that the greater the gloss uniformity and overall glossiness of the target spraying area, the better the gloss characteristic effect of the surface of the target spraying area. Therefore, the gloss uniformity and overall glossiness of the target spraying area can be combined to obtain the gloss effect value of the target spraying area.

[0070] In the embodiment of the present invention, the sum or product of the gloss uniformity and the overall glossiness of the target spraying area may be used as the gloss effect value of the target spraying area to achieve a combination of the two, which is not limited here.

[0071] As an example, in one embodiment of the present invention, the expression of the gloss effect value of the target spraying area may be specifically, for example, as follows:

[0072]

[0073] in, Indicates the gloss effect value of the target spraying area; Indicates the gloss uniformity of the target spraying area; It represents the average value of the gloss data of all measurement positions in the target spraying area, that is, the overall gloss of the target spraying area.

[0074] The gloss effect values ​​of the current spraying area and each historical spraying area can be calculated by the same method as above. In the embodiment of the present invention, the gloss effect of each area after painting is controlled by adjusting the spray pressure of the spraying equipment. From the above analysis, it can be seen that in the process of painting different areas of automobile parts, it is necessary to ensure that the gloss of each area after painting is relatively uniform. That is to say, after the current spraying area is painted, it is necessary to ensure that the gloss of the current spraying area after painting is similar to that of the historical spraying area. Therefore, before the current spraying area is painted, it is necessary to obtain the difference in gloss effect values ​​between the current spraying area and the historical spraying area to obtain the difference in gloss effect of the current spraying area. Subsequently, based on the difference in gloss effect of the current spraying area, the spray pressure of the spraying equipment can be adjusted so that the gloss characteristics of the current spraying area after painting and the historical spraying area are more similar.

[0075] Preferably, in one embodiment of the present invention, the method for obtaining the gloss effect difference of the current spraying area specifically includes:

[0076] The average value of the gloss effect values ​​of all historical spraying areas is taken as the historical overall effect value; the difference between the gloss effect value of the current spraying area and the historical overall effect value is normalized as the gloss effect difference of the current spraying area. When the gloss effect difference is greater than 0 and the larger it is, the gloss effect of the current spraying area is larger than that of each historical spraying area, and the spray pressure needs to be reduced to a greater extent in the future. When the gloss effect difference is less than 0 and the smaller it is, the gloss effect of the current spraying area is smaller than that of each historical spraying area, and the spray pressure needs to be increased to a greater extent in the future to ensure that the surface gloss characteristics of the current spraying area after painting are similar to those of the historical spraying areas.

[0077] As an example, in one embodiment of the present invention, the expression of the gloss effect difference of the current spraying area can be specifically, for example, as follows:

[0078]

[0079] in, Indicates the difference in gloss effect of the current spraying area, the value range is ; Indicates the gloss effect value of the current spraying area; Indicates The gloss effect value of the historical spraying area; Indicates the number of historical sprayed areas; It represents the average gloss effect value of all historical spraying areas, that is, the historical overall effect value; represents a hyperbolic tangent function, which is used for normalization processing. In other embodiments of the present invention, other related functions may also be used to implement normalization processing.

[0080] Step S3: According to the distribution of height data of different measuring points in the current spraying area, the concave-convex characteristic value of the current spraying area is obtained; based on the gloss effect difference and the concave-convex characteristic value of the current spraying area, the rated spray pressure of the spraying equipment is adjusted to obtain the real-time spray pressure of the spraying equipment in the current spraying area; the current spraying area is painted by the spraying equipment using the real-time spray pressure, and the current spraying area after painting is used as the historical spraying area, and the next non-historical spraying area is used as the new current spraying area, the real-time spray pressure of the spraying equipment in the new current spraying area is updated, and the new current spraying area is painted until the painting of the automobile parts is completed, and the painted automobile parts of the current painting round are obtained.

[0081] Since the surface conditions of automobile parts are relatively complex, with concave areas and convex areas, during the curing process of the paint, the paint in the convex areas will flow into the concave areas, resulting in different deposition thicknesses of the paint in the concave areas and the convex areas, which in turn leads to uneven gloss in the concave areas and the convex areas after painting. Therefore, for spraying areas with different surface concave and convex conditions, the subsequent adjustment of the spray pressure of the spraying equipment is also different. The height data of each measuring point in the current spraying area can reflect the concave and convex conditions of its surface. Therefore, the distribution of the height data of different measuring points in the current spraying area can be analyzed, and the concave and convex characteristic values ​​obtained can be used to reflect the concave and convex conditions of the surface of the current spraying area. Subsequently, the spray pressure of the spraying equipment can be adjusted in combination with the concave and convex characteristic values ​​of the current spraying area and the difference in gloss effect, thereby improving the painting effect and efficiency of automobile parts.

[0082] Preferably, in one embodiment of the present invention, the method for obtaining the concave-convex feature value of the current spraying area specifically includes:

[0083] The maximum value of all height data of the current spraying area is taken as the numerator, the minimum value of all height data of the current spraying area is taken as the denominator, and the ratio is taken as the first concave-convex parameter of the current spraying area. The larger the first concave-convex parameter, the more uneven the surface of the current spraying area is. Subsequently, the concave-convex characteristic value of the current spraying area can be accurately calculated based on the first concave-convex parameter.

[0084] Perform curve fitting on the height data of all measurement points in the current spraying area to obtain the height fitting curve of the current spraying area. The curve fitting method can use the existing least square method or other methods, which are not limited or elaborated here; connect the two end points of the height fitting curve to obtain the reference line segment of the current spraying area; take the area surrounded by the height fitting curve and the reference line segment as the reference area, take the reference area below the reference line segment as the lower reference area, and take the reference area above the reference line segment as the upper reference area. Please refer to Figure 3 , which shows a schematic diagram of an upper reference area and a lower reference area provided by an embodiment of the present invention, wherein the horizontal axis of the coordinate system represents the horizontal distance between the measuring point on the surface of the current spraying area and the starting end point of the current spraying area, the vertical axis represents the height data of the measuring point on the surface of the current spraying area, curve b represents the height fitting curve of the current spraying area, line segment a represents the reference line segment of the current spraying area, areas Q1 and Q2 represent the upper reference area, and areas Q3 and Q4 represent the lower reference area; if the lower reference area is larger than the upper reference area, it means that the surface of the current spraying area presents a concave feature, and if the lower reference area is smaller than the upper reference area, it means that the surface of the current spraying area presents a convex feature, so the difference in area between the lower reference area and the upper reference area can be used as the second concave-convex parameter of the current spraying area.

[0085] Then, the product value of the first concave-convex parameter and the second concave-convex parameter of the current spraying area is normalized to obtain the concave-convex characteristic value of the current spraying area. If the concave-convex characteristic value is greater than 0 and the larger it is, it means that the current spraying area as a whole presents a concave feature, and the spray pressure needs to be reduced to a greater extent in the future. If the concave-convex characteristic value is less than 0 and the smaller it is, it means that the current spraying area as a whole presents a convex feature, and the spray pressure needs to be increased to a greater extent in the future.

[0086] As an example, in one embodiment of the present invention, the expression of the concave-convex feature value of the current spraying area can be specifically, for example, as follows:

[0087]

[0088] in, Indicates the concave and convex characteristic value of the current spraying area, the value range is ; Indicates the maximum value of all height data in the current spraying area; Indicates the minimum value of all height data in the current spraying area; Indicates the first concave-convex parameter of the current spraying area; represents the area of ​​the reference region below; represents the area of ​​the upper reference area, where and It can be obtained by integration, which will not be elaborated here; Indicates the second concave-convex parameter of the current spraying area; represents a hyperbolic tangent function, which is used for normalization processing. In other embodiments of the present invention, other related functions may also be used to implement normalization processing.

[0089] From the above analysis, it can be known that when the gloss effect difference and the concave-convex characteristic value of the current spraying area are greater than 0 and the larger they are, the spray pressure needs to be reduced to a greater extent; when the gloss effect difference and the concave-convex characteristic value of the current spraying area are less than 0 and the smaller they are, the spray pressure needs to be increased to a greater extent. Therefore, based on the gloss effect difference and the concave-convex characteristic value of the current spraying area, the rated spray pressure of the spraying equipment can be adjusted to obtain the real-time spray pressure of the spraying equipment in the current spraying area. Subsequently, the current spraying area can be painted by using the spraying equipment with real-time spray pressure to improve the painting effect of the current spraying area, thereby improving the painting efficiency of automobile parts.

[0090] Preferably, in one embodiment of the present invention, the method for obtaining the real-time spray pressure of the spraying equipment in the current spraying area specifically includes:

[0091] The gloss effect difference and the sum of the concave-convex characteristic values ​​of the current spraying area are normalized to obtain the spray pressure adjustment coefficient of the current spraying area. The value range of the spray pressure adjustment coefficient is When the spray pressure adjustment parameter is greater than 0 and the larger it is, the more the spray pressure needs to be reduced; when the spray pressure reference is less than 0 and the smaller it is, the more the spray pressure needs to be increased. Therefore, the difference between the value 1 and the spray pressure adjustment coefficient can be used as the adjustment degree of the current spraying area, and the product of the adjustment degree and the rated spray pressure of the spraying equipment can be used as the real-time spray pressure of the spraying equipment in the current spraying area.

[0092] As an example, in one embodiment of the present invention, the expression of the real-time spray pressure of the spraying equipment in the current spraying area can be specifically, for example, as follows:

[0093]

[0094]

[0095] in, Indicates the real-time spray pressure of the spray equipment in the current spray area; Indicates the rated spray pressure of the spray equipment; Indicates the spray pressure adjustment coefficient of the current spraying area, the value range is ; Indicates the adjustment degree of the current spraying area; Indicates the difference in gloss effect of the current spraying area; Indicates the concave and convex feature value of the current spraying area; represents a hyperbolic tangent function, which is used for normalization processing. In other embodiments of the present invention, other related functions may also be used to implement normalization processing.

[0096] Through the above steps, the real-time spray pressure of the spray equipment in the current spraying area is obtained, and then the current spraying area can be painted by using the spray equipment with real-time spray pressure, so that the subsequent painting of automobile parts can achieve the expected effect faster, and the current spraying area after painting is used as the historical spraying area, and then the spraying equipment is controlled to move to the next non-historical spraying area that has not been painted, and the next non-historical spraying area is used as the new current spraying area, and the real-time spray pressure of the spray equipment in the new current spraying area is updated through the same method as above, and the new current spraying area is painted until the painting of automobile parts is completed, and the painting process of automobile parts in the current painting round is completed, thereby obtaining the painted automobile parts of the current painting round.

[0097] It should be noted that the gloss data of the surface of the current spraying area will change before and after painting. Therefore, before the spraying equipment moves to the next non-historical spraying area, a gloss meter is required to collect and record the gloss data of different measuring positions in the current spraying area after painting, so as to accurately calculate and analyze the gloss effect value of the current spraying area after painting, thereby realizing the calculation of the real-time spray pressure of the new current spraying area.

[0098] Step S4: Determine whether to perform the next round of painting on the painted automobile parts.

[0099] Through the above, the painting process of the automobile parts in the current painting round is completed. At this time, there is no non-historical spraying area for the painted automobile parts, only the historical spraying area. In order to achieve the expected painting effect, it is usually necessary to paint the automobile parts for multiple rounds. Therefore, it is necessary to evaluate the gloss effect of the painted automobile parts in the current painting round to determine whether the next round of painting is needed. In the current painting round, the adjustment amount of the spray pressure of the spraying equipment can reflect the gloss effect of the painted automobile parts to a certain extent. That is to say, in the current painting round, the real-time adjustment amount of the spraying equipment in each historical spraying area The smaller the difference between the spray pressure and the rated spray pressure, the smaller the adjustment of the spray pressure of the spray equipment is, which further indicates that the gloss effect of the painted automobile parts in the current painting round is better, and the more consistent the gloss effect values ​​of all historical spraying areas of the painted automobile parts are, the better the gloss effect of the painted automobile parts in the current painting round is. Therefore, the difference between the real-time spray pressure and the rated spray pressure of the historical spraying areas of the painted automobile parts and the distribution of the gloss effect values ​​of all historical spraying areas can be analyzed to determine whether to carry out the next round of painting on the painted automobile parts, reduce the rounds of painting of automobile parts, and improve painting efficiency.

[0100] Preferably, in one embodiment of the present invention, the method for determining whether to perform the next round of painting on automobile parts specifically includes:

[0101] First, the discrete degree of the gloss effect values ​​of all historical spraying areas of painted automobile parts is analyzed to obtain the first painting evaluation value of the current painting round. The smaller the first painting evaluation value, the more uniform the gloss of each historical spraying area of ​​the painted automobile parts, and thus the better the gloss effect of the current painting round.

[0102] In an embodiment of the present invention, the variance or standard deviation of the gloss effect values ​​of all historical spraying areas of painted automobile parts can be used as the first painting evaluation value of the current painting round to analyze the discrete degree of the gloss effect values ​​of all historical spraying areas of painted automobile parts, which is not limited here.

[0103] Then the absolute value of the difference between the real-time spray pressure and the rated spray pressure of each historical spraying area of ​​the painted automobile parts is taken as the spray pressure change of each historical spraying area; the average value of the spray pressure change of all historical spraying areas is taken as the second painting evaluation value of the current painting round. The smaller the second painting evaluation value is, the smaller the adjustment of the spray pressure of the spray equipment in the current painting round, and thus the better the gloss effect of the current painting round.

[0104] Then, the first painting evaluation value and the second painting evaluation value are integrated and normalized to obtain a comprehensive painting evaluation value of the current painting round.

[0105] In the embodiment of the present invention, the integration of the first coating evaluation value and the second coating evaluation value can be achieved by calculating the sum or product of the two values, which is not limited here.

[0106] As an example, in one embodiment of the present invention, the expression of the comprehensive painting evaluation value of the current painting round may be specifically, for example, as follows:

[0107]

[0108] in, Indicates the comprehensive coating evaluation value of the current coating round, with a value range of ; Indicates the first painting evaluation value of the current painting round; Indicates the spraying equipment in the coating of automotive parts The real-time spray pressure of the first historical spraying area. Since the first historical spraying area is directly painted using the rated spray pressure, the real-time spray pressure of the first historical spraying area can be considered as the rated spray pressure. Indicates the rated spray pressure of the spray equipment; Indicates the spraying equipment in the coating of automotive parts The change of spray pressure in the historical spraying area; Indicates the number of historical spray areas where automotive parts were painted; Indicates the second painting evaluation value of the current painting round; represents a hyperbolic tangent function, which is used for normalization processing. In other embodiments of the present invention, other related functions may also be used to implement normalization processing.

[0109] The smaller the comprehensive painting evaluation value is, the better the painting effect of the current painting round is. Therefore, based on the comprehensive painting evaluation value, it can be judged whether to carry out the next round of painting on the painted automobile parts.

[0110] Preferably, in one embodiment of the present invention, the method for determining whether to perform the next round of painting on automobile parts further comprises:

[0111] If the coating effect evaluation value is less than the preset evaluation threshold, it means that the expected coating effect has been achieved, and the next round of coating will not be carried out on the coated automobile parts. Otherwise, it means that the expected coating effect has not been achieved, and the next round of coating will continue to be carried out on the coated automobile parts. The value range of the preset evaluation threshold is In one embodiment of the present invention, the preset evaluation threshold is set to 0.2. The specific value of the preset evaluation threshold can also be set by the implementer according to the specific implementation scenario, which is not limited here.

[0112] The present invention also proposes a fully automatic coating line for automobile parts, including a spraying device. The coating line also includes a spraying control module for controlling the spraying equipment, a gloss meter for collecting gloss data for each spraying area of ​​the automobile parts, and a surface profiler for collecting height data of each spraying area. The spraying control module samples and connects the gloss meter and the surface profiler to obtain gloss data and height data, and processes the gloss data and height data to implement the method described in steps S1 to S4.

[0113] It should be noted that the sequence of the above embodiments of the present invention is only for description and does not represent the advantages and disadvantages of the embodiments. The processes depicted in the accompanying drawings do not necessarily require the specific order or continuous order shown to achieve the desired results. In some embodiments, multitasking and parallel processing are also possible or may be advantageous.

[0114] The various embodiments in this specification are described in a progressive manner, and the same or similar parts between the various embodiments can be referenced to each other, and each embodiment focuses on the differences from other embodiments.

Claims

1. A control method for a fully automatic coating line for automobile parts, characterized in that: The method comprises: Obtain gloss data of different measuring positions in the current spraying area and each historical spraying area of ​​the automobile parts in the current painting round, and height data of different measuring points in the current spraying area; Taking the current spraying area or any one of the historical spraying areas as the target spraying area, obtaining the gloss effect value of the target spraying area according to the distribution of glossiness data of all measurement positions in the target spraying area; obtaining the gloss effect difference of the current spraying area according to the difference between the gloss effect value of the current spraying area and the gloss effect value of each historical spraying area; According to the distribution of height data of different measuring points in the current spraying area, the concave-convex characteristic value of the current spraying area is obtained; based on the gloss effect difference of the current spraying area and the concave-convex characteristic value, the rated spray pressure of the spraying equipment is adjusted to obtain the real-time spray pressure of the spraying equipment in the current spraying area; the current spraying area is painted by the spraying equipment using the real-time spray pressure, and the current spraying area after painting is used as the historical spraying area, and the next non-historical spraying area is used as the new current spraying area, the real-time spray pressure of the spraying equipment in the new current spraying area is updated, and the new current spraying area is painted until the painting of the automobile parts is completed, so as to obtain the painted automobile parts of the current painting round; Determine whether to proceed with the next round of painting on the painted automobile parts.

2. The method for controlling a fully automatic coating line for automobile parts according to claim 1, characterized in that: The step of obtaining the gloss effect value of the target spraying area comprises: Obtaining the gloss uniformity of the target spraying area according to the difference of the gloss data at any two measurement positions in the target spraying area; Obtaining the overall glossiness of the target spraying area according to the overall distribution level of the glossiness data at all measurement positions in the target spraying area; The gloss uniformity and the overall glossiness of the target spraying area are combined to obtain a gloss effect value of the target spraying area.

3. A method for controlling a fully automatic coating line for automobile parts according to claim 2, characterized in that: The method of obtaining the gloss uniformity of the target spraying area includes: Taking any two measurement positions in the target spraying area as a measurement position group, and taking the absolute value of the difference between the gloss data of the two measurement positions in each measurement position group as the initial gloss difference value of each measurement position group; The average values ​​of the initial gloss difference values ​​of all measurement position groups are negatively correlated to obtain the gloss uniformity of the target spraying area.

4. The method for controlling a fully automatic coating line for automobile parts according to claim 1, characterized in that: The obtaining of the gloss effect difference of the current spraying area includes: The average of the gloss effect values ​​of all historical spraying areas is taken as the historical overall effect value; The difference between the gloss effect value of the current spraying area and the historical overall effect value is normalized to serve as the gloss effect difference of the current spraying area.

5. The method for controlling a fully automatic coating line for automobile parts according to claim 1, characterized in that: The obtaining of the concave-convex characteristic value of the current spraying area comprises: The maximum value of all height data of the current spraying area is used as the numerator, the minimum value of all height data of the current spraying area is used as the denominator, and the ratio is used as the first concave-convex parameter of the current spraying area; Performing curve fitting on the height data of all measuring points in the current spraying area to obtain a height fitting curve of the current spraying area; connecting two end points of the height fitting curve to obtain a reference line segment of the current spraying area; The area enclosed by the height fitting curve and the reference line segment is used as a reference area, the reference area below the reference line segment is used as a lower reference area, and the reference area above the reference line segment is used as an upper reference area; the difference in area between the lower reference area and the upper reference area is used as a second concave-convex parameter of the current spraying area; The product value of the first concavo-convex parameter and the second concavo-convex parameter of the current spraying area is normalized to obtain the concavo-convex characteristic value of the current spraying area.

6. The method for controlling a fully automatic coating line for automobile parts according to claim 1, characterized in that: The obtaining of the real-time spray pressure of the spraying equipment in the current spraying area comprises: Normalizing the gloss effect difference and the sum of the concave-convex characteristic values ​​of the current spraying area to obtain a spray pressure adjustment coefficient of the current spraying area; The difference between the value 1 and the spray pressure adjustment coefficient is used as the adjustment degree of the current spraying area, and the product of the adjustment degree and the rated spray pressure of the spraying equipment is used as the real-time spray pressure of the spraying equipment in the current spraying area.

7. The method for controlling a fully automatic coating line for automobile parts according to claim 1, characterized in that: The step of determining whether to perform the next round of painting on the painted automobile parts includes: According to the difference between the real-time spray pressure and the rated spray pressure of the historical spraying area of ​​the painted automobile part and the distribution of the gloss effect values ​​of all historical spraying areas, it is determined whether to perform the next round of painting on the painted automobile part.

8. The method for controlling a fully automatic coating line for automobile parts according to claim 7, characterized in that: The step of judging whether to perform the next round of painting on the painted automobile parts according to the difference between the real-time spray pressure and the rated spray pressure of the historical spraying area of ​​the painted automobile parts and the distribution of the gloss effect values ​​of all the historical spraying areas includes: Analyzing the discrete degree of the gloss effect value of all historical spraying areas of the painted automobile parts to obtain a first painting evaluation value of the current painting round; The absolute value of the difference between the real-time spray pressure and the rated spray pressure of each historical spraying area of ​​the painted automobile parts is used as the spray pressure change of the spraying equipment in each historical spraying area; the average value of the spray pressure change of all historical spraying areas is used as the second painting evaluation value of the current painting round; The first coating evaluation value and the second coating evaluation value are integrated and normalized to obtain a comprehensive coating evaluation value of the current coating round; Based on the comprehensive painting evaluation value, it is determined whether to perform the next round of painting on the painted automobile parts.

9. A control method for a fully automatic coating line for automobile parts according to claim 8, characterized in that: The step of judging whether to perform the next round of painting on the painted automobile parts based on the comprehensive painting evaluation value includes: If the coating effect evaluation value is less than a preset evaluation threshold, the next round of coating will not be performed on the coated automobile parts; otherwise, the next round of coating will continue to be performed on the coated automobile parts.

10. A fully automatic coating line for automobile parts, including spraying equipment, characterized in that: The coating line also includes a spray control module for controlling the spray equipment, a gloss meter for collecting gloss data for each spray area of ​​the automobile parts, and a surface profiler for collecting height data of each spray area. The spray control module samples and connects the gloss meter and the surface profiler to obtain gloss data and height data, and processes the gloss data and height data to implement the steps of the method as described in any one of claims 1 to 9.

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