Calibration method of size measurement comprehensive parameter calibration ball group target

Abstract

The invention provides a calibration method of a size measurement comprehensive parameter calibration ball group target. The calibration method comprises the following steps: S1, designing and manufacturing the size measurement comprehensive parameter calibration ball group target; s2, calibrating the metrological characteristic parameters of the size measurement comprehensive parameter calibration ball group target by adopting a high-precision calibration standard device; and S3, calibrating the size parameter capability of the industrial CT equipment for measuring the key features by using the size measurement comprehensive parameter calibration ball group target. According to the invention, the measurement size is larger, the calibration of the cone and cylinder parameters of the industrial CT equipment can be provided, and the accuracy of measuring the cone and cylinder parameters of the industrial CT equipment is improved. Through the brand-new structural design, one-time metering calibration of various size parameters can be achieved, repeated metering calibration of traditional forest balls, special cones and cylindrical standard devices is replaced, and the calibration efficiency of industrial CT equipment is improved.

Description

Technical Field

[0001] The invention relates to the technical field of size detection, and in particular to a calibration method for a size measurement comprehensive parameter calibration ball target set. Background Art

[0002] Industrial CT is based on X-ray non-contact perspective imaging to achieve 3D reconstruction and geometric dimension measurement of the measured parts. Compared with traditional measurement methods, industrial CT can measure the internal dimensions of parts, which is of great significance for the internal dimension inspection of parts that are not visible or cannot be measured externally.

[0003] Before measuring the dimensions of a part, industrial CT measuring equipment usually needs to be calibrated with a standard part to calibrate its measurement accuracy. Currently, industrial CT measuring equipment is mainly calibrated with a standard part, the forest ball. The calibration dimensions that the forest ball can provide mainly include the ball diameter and the ball center distance.

[0004] At present, the size that the forest ball can calibrate is relatively small. For the measurement of larger parts, additional standard parts (such as bats and paddles, etc.) are often required to calibrate the industrial CT equipment before measurement. Due to the use of a variety of different standard parts, on the one hand, the calibration time is longer, and on the other hand, the management of on-site standards is more difficult, which increases the calibration cost of industrial CT equipment for measuring complex parts and the difficulty of maintaining different standard parts.

[0005] According to the above description, the technical problems that need to be solved are as follows:

[0006] 1. Solve the problem that the forest ball calibration size is small and does not provide cone and cylinder parameter calibration;

[0007] Second, solve the problem of insufficient calibration capability of forest ball size parameters when measuring complex parts, and the need for additional standard equipment for supplementary calibration, which leads to reduced calibration efficiency;

[0008] 3. Solve the problem of high maintenance and management costs and difficulties caused by the large variety of size calibration standards currently available for industrial CT equipment.

[0009] In view of this, the inventors of the present application have designed a calibration method for a size measurement comprehensive parameter calibration ball set target in order to overcome the above technical problems. Summary of the invention

[0010] The technical problem to be solved by the present invention is to overcome the defects in the prior art such as the small calibration size of the forest ball and the low calibration efficiency of the additional standard device for supplementary calibration, and to provide a calibration method for a ball set target for size measurement comprehensive parameters.

[0011] The present invention solves the above technical problems through the following technical solutions:

[0012] A calibration method for a size measurement comprehensive parameter calibration ball set target, characterized in that the calibration method comprises the following steps:

[0013] S1. Design and manufacture dimensional measurement comprehensive parameter calibration ball set targets;

[0014] S2. Use high-precision calibration standards to calibrate the metrological characteristic parameters of the dimensional measurement comprehensive parameter calibration ball set target;

[0015] S3. Use the dimensional measurement comprehensive parameter calibration ball target set to calibrate the dimensional parameter measurement capability of the industrial CT equipment for key features.

[0016] According to one embodiment of the present invention, step S1 includes:

[0017] S 11 The size measurement comprehensive parameter calibration ball set target includes a main standard ball and multiple auxiliary standard balls;

[0018] S 12 , the main standard ball and a plurality of auxiliary standard balls are mounted on the node ball through thin rods;

[0019] S 13 The node ball is mounted on the disc-shaped base via a thin rod.

[0020] According to one embodiment of the present invention, the step S1 further includes:

[0021] S 14 , a line connecting the center of the main standard sphere and the center of the node sphere is perpendicular to the upper surface of the disc-shaped base;

[0022] S 15 , the distance between the center of the auxiliary standard sphere and the center of the node sphere is the same, and the center of the auxiliary standard sphere is located on a spherical surface concentric with the node sphere;

[0023] S 16 , the angle between the line connecting the center of each auxiliary standard sphere and the center of the node sphere is equal to the angle between the line connecting the center of the main standard sphere and the center of the node sphere.

[0024] According to one embodiment of the present invention, the step S1 further includes:

[0025] S 17 , the auxiliary standard balls include 8 auxiliary standard balls, which are symmetrically distributed in two layers, with 4 auxiliary standard balls distributed in each layer;

[0026] S 18 The centers of the auxiliary standard balls in each layer are located on the same plane circle and equally divide the plane circle.

[0027] According to one embodiment of the present invention, the metrological characteristic parameters of the size measurement comprehensive parameter calibration ball group target in step S2 include: the roundness and diameter of the main standard ball and the auxiliary standard ball; the distance between the centers of two non-adjacent auxiliary standard balls in the upper layer; the distance between the centers of the corresponding auxiliary standard balls in the upper and lower layers in the direction of the line connecting the node ball and the center of the main standard ball; the distance between the centers of the two balls in the upper and lower layers of auxiliary standard balls whose corresponding center lines pass through the center of the node ball; the cone angle of the cone formed by the center of the main standard ball and the centers of multiple auxiliary standard balls in the upper and lower layers; and the diameter of the cylinder formed by the centers of multiple auxiliary standard balls.

[0028] According to one embodiment of the present invention, the high-precision calibration standard in step S2 includes a high-precision coordinate measuring machine or a roundness meter; the ratio of the measurement uncertainty of the high-precision coordinate measuring machine to the measurement uncertainty of the calibrated industrial CT equipment is less than or equal to 0.1.

[0029] According to one embodiment of the present invention, step S3 includes:

[0030] S 31 , placing the size measurement comprehensive parameter calibration ball set target on the industrial CT equipment measurement workbench, and scanning and measuring the main standard ball and multiple auxiliary standard balls;

[0031] According to one embodiment of the present invention, the step S 31 The method then includes: after the scanning is completed, using industrial CT measurement software to measure the diameter of the main standard ball, and calculating the deviation between the industrial CT measured value and the calibration value of the corresponding metrological characteristic parameter in step S2, and using the deviation as the calibration value of the ball parameter.

[0032] According to one embodiment of the present invention, the step S 31 It also includes: after the scanning is completed, using industrial CT measurement software to measure the distance between the centers of two non-adjacent balls of the upper auxiliary standard ball, and calculating the deviations between the industrial CT measured value and the calibration value of the corresponding metrological characteristic parameter in step S2, and using the deviations as calibration values ​​of the length parameters along the X-axis and Y-axis directions of the coordinate system.

[0033] According to one embodiment of the present invention, the step S 31 It also includes: after the scanning is completed, using industrial CT measurement software to measure the distance between the center of the auxiliary standard spheres corresponding to the upper and lower layers along the direction of the line connecting the node sphere and the main standard sphere, and calculating the deviation between the industrial CT measured value and the corresponding metrological characteristic parameter calibration value in step S2, and using the deviation as the calibration value of the length parameter along the Z-axis direction of the coordinate system.

[0034] According to one embodiment of the present invention, the step S 31It also includes: after the scanning is completed, using industrial CT measurement software to measure the distance between the centers of the two balls in the upper and lower layers of auxiliary standard balls, corresponding to the center line passing through the center of the node ball, and calculating the deviation between the industrial CT measured value and the corresponding metrological characteristic parameter calibration value in step S2, and using the deviation as the calibration value of the length parameter along the diagonal direction of the coordinate system space.

[0035] According to one embodiment of the present invention, the step S 31 The method also includes: after the scanning is completed, using industrial CT measurement software to measure the cone angle of the cone formed by the center of the main standard ball and the centers of the upper and lower layers of multiple auxiliary standard balls, and calculating the deviation between the industrial CT measured value and the corresponding metrological characteristic parameter calibration value in step S2, and using the deviation as the cone angle parameter calibration value of the cone.

[0036] According to one embodiment of the present invention, the step S 31 It also includes: after the scanning is completed, using industrial CT measurement software to measure the diameter of the cylinder formed by the centers of multiple auxiliary standard balls, and calculating the deviation between the industrial CT measured value and the corresponding metrological characteristic parameter calibration value in step S2, and using the deviation as the diameter parameter calibration value of the cylinder.

[0037] The positive and progressive effects of the present invention are:

[0038] The calibration method of the size measurement comprehensive parameter calibration ball set target of the present invention has the following advantages:

[0039] 1. Compared with the forest ball standard, the measuring size of the present invention is larger, and it can provide calibration of the cone and cylinder parameters of industrial CT equipment, thereby improving the accuracy of measuring the cone and cylinder parameters of industrial CT equipment;

[0040] Second, through the new structural design, the present invention can realize one-time metrological calibration of multiple size parameters, replacing the multiple metrological calibrations of traditional forest balls, special cones and cylinder standards, and improving the calibration efficiency of industrial CT equipment;

[0041] 3. The calibration ball target set of the present invention has a simple structure and is easy to use and maintain, and can solve the problem of high maintenance and management costs and difficulty caused by the large variety of size calibration standards currently available for industrial CT equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] The above and other features, properties and advantages of the present invention will become more apparent through the following description in conjunction with the accompanying drawings and embodiments, in which the same reference numerals always represent the same features, wherein:

[0043] Figure 1 The present invention is a flow chart of a calibration method for calibrating a ball set target for dimension measurement comprehensive parameters.

[0044] Figure 2 A stereoscopic diagram of a calibration ball set target used in the calibration method for calibrating a ball set target for comprehensive parameter measurement of the present invention.

[0045] Figure 3 A top view of a calibration ball set target used in the calibration method for calibrating a ball set target for comprehensive parameter measurement of the present invention.

[0046] Figure 4 This is a front view of a calibration ball set target used in the calibration method for calibrating a ball set target for comprehensive parameter measurement of the present invention.

[0047] Figure 5 The diagram is a schematic diagram of the length dimension calibration along the X-axis and Y-axis directions of the coordinate system for the calibration method of the dimensional measurement comprehensive parameter calibration ball set target of the present invention.

[0048] Figure 6 It is a schematic diagram of length dimension calibration along the Z-axis direction of the coordinate system for the calibration method of the dimension measurement comprehensive parameter calibration ball set target of the present invention.

[0049] Figure 7 It is a schematic diagram of the calibration of the length dimension in the spatial diagonal direction in the calibration method of the ball set target for comprehensive parameter calibration of dimension measurement of the present invention.

[0050] Figure 8 It is a schematic diagram of the cone structure in the calibration method of the dimensional measurement comprehensive parameter calibration ball set target of the present invention.

[0051] Fig. 9 It is a schematic diagram of the cylindrical structure in the calibration method of the dimensional measurement comprehensive parameter calibration ball set target of the present invention. DETAILED DESCRIPTION

[0052] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the specific embodiments of the present invention are described in detail below with reference to the accompanying drawings.

[0053] Embodiments of the present invention will now be described in detail with reference to the accompanying drawings. Reference will now be made in detail to preferred embodiments of the present invention, examples of which are shown in the accompanying drawings. Wherever possible, the same reference numerals will be used throughout the drawings to represent the same or similar parts.

[0054] Furthermore, although the terms used in the present invention are selected from well-known and commonly used terms, some terms mentioned in the present invention specification may be selected by the applicant at his or her discretion, and their detailed meanings are explained in the relevant parts of the description of this document.

[0055] Furthermore, it is required that the present invention be understood not only by the actual terms used but also by the meanings connoted by each term.

[0056] like Figures 1 to 9 As shown, the present invention discloses a calibration method for a size measurement comprehensive parameter calibration ball set target, which comprises the following steps:

[0057] Step S1, design and manufacture a size measurement comprehensive parameter calibration ball set target, such as Figure 2 shown.

[0058] Preferably, the step S1 includes:

[0059] Step S 11 The size measurement comprehensive parameter calibration ball set target includes a main standard ball and multiple auxiliary standard balls (e.g., 8 auxiliary standard balls). The standard balls are preferably made of wear-resistant materials (e.g., artificial ruby, silicon nitride ceramics, etc.).

[0060] Step S 12 The main standard ball and multiple auxiliary standard balls are installed on the node ball through thin rods.

[0061] Here, the thin rod is preferably a high-strength thin rod, for example, made of carbon fiber, silicon nitride ceramics or the like.

[0062] Step S 13 The node ball is mounted on the disc-shaped base via a thin rod.

[0063] Here, the thin rod is preferably a high-strength thin rod, for example, made of carbon fiber, silicon nitride ceramics, etc. The disc-shaped base is preferably a cast iron base.

[0064] Furthermore, the step S1 may also include the following steps:

[0065] Step S 14 , the line connecting the center of the main standard sphere and the center of the node sphere is perpendicular to the upper surface of the disc-shaped base.

[0066] Step S 15 In this embodiment, the distances between the centers of the eight auxiliary standard spheres and the center of the node sphere are the same, that is, the centers of the eight auxiliary standard spheres are located on a spherical surface concentric with the node sphere.

[0067] Step S 16 , the angle between the line connecting the center of each auxiliary standard sphere and the center of the node sphere is equal to the angle between the line connecting the center of the main standard sphere and the center of the node sphere.

[0068] For example, in this embodiment, the angle is 30°. In addition to this embodiment, other optional angles may be 15°, 45°, 60° and 75°.

[0069] Furthermore, in this embodiment, step S1 may further include the following steps:

[0070] Step S 17 The auxiliary standard balls include 8 auxiliary standard balls, which are symmetrically distributed in two layers, and there are 4 auxiliary standard balls in each layer.

[0071] Step S 18 , the centers of the auxiliary standard balls in each layer are located on the same plane circle and equally divide the plane circle. For example, the centers of the four auxiliary standard balls in each layer are located on the same plane circle and equally divide the plane circle.

[0072] Preferably, in this embodiment, the positive direction of the X-axis of the design coordinate system of the dimension measurement comprehensive parameter calibration ball set target is the same as the vector direction determined by the center of the auxiliary standard sphere 3 (7) and the center of the auxiliary standard sphere 1 (5).

[0073] Preferably, in this embodiment, the positive direction of the Y axis of the design coordinate system of the dimension measurement comprehensive parameter calibration ball set target is the same as the vector direction determined by the center of the auxiliary standard ball 4 (8) and the center of the auxiliary standard ball 2 (6).

[0074] Preferably, in this embodiment, the positive direction of the Z axis of the design coordinate system of the size measurement comprehensive parameter calibration ball set target is the same as the vector direction determined by the center of the node ball and the center of the main standard ball.

[0075] In this embodiment, the diameter of the main standard ball is preferably 10 mm, and the diameter of the auxiliary standard ball is preferably 8 mm. The diameter of the node ball is the same as the diameter of the auxiliary standard ball, and the diameter of the thin rod is 0.5 times the diameter of the auxiliary standard ball. In addition to this embodiment, other optional main standard ball diameters may also be preferably 5 mm,

[0076] 15mm, 20mm, 25mm, other optional auxiliary standard ball diameters may also be preferably 4mm, 12mm, 16mm, 20mm.

[0077] In this embodiment, the design is based on the principle that the projection distance between the two planes where the centers of the upper and lower auxiliary standard balls are located along the Z-axis direction of the coordinate system should not be less than 66% of the measurement range of the instrument in the same direction.

[0078] Step S2: using a high-precision calibration standard to calibrate the metrological characteristic parameters of the size measurement comprehensive parameter calibration ball set target.

[0079] Preferably, step S2 comprises the following steps:

[0080] Step S 21 The high-precision calibration standard includes a high-precision coordinate measuring machine or a roundness meter, or other similar equipment, etc.

[0081] Step S22 , the ratio of the measurement uncertainty of the high-precision coordinate measuring machine to the measurement uncertainty of the calibrated industrial CT equipment is less than or equal to 0.1.

[0082] Furthermore, the step S2 further comprises the following steps:

[0083] Step S 23 The metrological characteristic parameters of the size measurement comprehensive parameter calibration ball set target include but are not limited to: the roundness and diameter of the main standard ball and the auxiliary standard ball.

[0084] Step S 24 The metrological characteristic parameters of the size measurement comprehensive parameter calibration ball set target include but are not limited to: the distance between the centers of two non-adjacent balls of the upper auxiliary standard ball.

[0085] In combination with this embodiment, the distance L between the center of the auxiliary standard sphere 1 and the center of the auxiliary standard sphere 3 along the X-axis of the coordinate system is x , is the distance L between the center of auxiliary standard sphere 2 and the center of auxiliary standard sphere 4 along the Y axis of the coordinate system y (like Figure 3 shown).

[0086] Step S 25 The metrological characteristic parameters of the size measurement comprehensive parameter calibration ball set target include but are not limited to: the distance between the centers of the upper and lower layers of corresponding auxiliary standard balls along the direction of the line connecting the node ball and the center of the main standard ball.

[0087] In combination with this embodiment, the distance is the average value L of the difference between the Z coordinate values ​​of the four pairs of auxiliary standard sphere centers along the Z axis of the coordinate system. z =(z1+z2+z3+z4) / 4(e.g. Figure 4 shown).

[0088] Step S 26 , the metrological characteristic parameters of the size measurement comprehensive parameter calibration ball set target include but are not limited to: the distance between the centers of the two balls in the upper and lower layers of auxiliary standard balls corresponding to the line connecting the centers of the balls passing through the centers of the node balls.

[0089] In combination with this embodiment, the distance is the distance d1 between the centers of the auxiliary standard ball 1 and the auxiliary standard ball 7, the distance d2 between the centers of the auxiliary standard ball 2 and the auxiliary standard ball 8, the distance d3 between the centers of the auxiliary standard ball 3 and the auxiliary standard ball 5, and the distance d4 between the centers of the auxiliary standard ball 4 and the auxiliary standard ball 6 (such as Figure 5 shown).

[0090] Step S 27 The metrological characteristic parameters of the size measurement comprehensive parameter calibration ball set target include but are not limited to: the cone angles of the cones formed by the center of the main standard ball and the centers of the upper and lower layers of multiple auxiliary standard balls.

[0091] In combination with this embodiment, the cone angles are respectively the cone angle of cone 1 formed by the center of the main standard ball and the centers of auxiliary standard balls 1, 2, 3 and 4, and the cone angle of cone 2 formed by the center of the main standard ball and the centers of auxiliary standard balls 5, 6, 7 and 8. The structures of cone 1 and cone 2 are shown in FIG. Figure 6 shown.

[0092] Step S 28 The metrological characteristic parameters of the size measurement comprehensive parameter calibration ball set target include but are not limited to: the diameter of the cylinder formed by the centers of multiple auxiliary standard balls (8 auxiliary standard balls). In combination with this embodiment, the cylinder constructed is as follows Figure 7 shown.

[0093] Step S3: using a dimensional measurement comprehensive parameter calibration ball target set to calibrate the dimensional parameter measurement capability of the industrial CT equipment for key features.

[0094] Preferably, the step S3 further comprises the following steps:

[0095] Step S 31 , place the size measurement comprehensive parameter calibration ball set target on the measuring workbench of the industrial CT equipment, and scan and measure the main standard ball and multiple auxiliary standard balls.

[0096] For example, the main standard sphere and eight auxiliary standard spheres are scanned and each size parameter is measured three times.

[0097] Furthermore, the step S 31 Later also includes:

[0098] Step S 32 After the scan is completed, the diameter of the main standard ball is measured using industrial CT measurement software, and the deviation between the industrial CT measured value and the calibration value of the corresponding metrological characteristic parameter in step S2 is calculated respectively, and the deviation is used as the calibration value of the ball parameter.

[0099] In combination with this embodiment, the measured dimensional parameters include but are not limited to the diameter of the main standard ball, and the deviations between the industrial CT measured values ​​and the calibration values ​​of the corresponding metrological characteristic parameters in step 2 are calculated respectively, and the deviations are used as the calibration values ​​of the ball parameters.

[0100] Step S 33 After the scan is completed, the industrial CT measurement software is used to measure the distance between the centers of the two non-adjacent balls of the upper auxiliary standard ball, and the deviations between the industrial CT measured value and the calibration value of the corresponding metrological characteristic parameter in step S2 are calculated respectively, and the deviations are used as the calibration values ​​of the length parameters along the X-axis and Y-axis directions of the coordinate system.

[0101] In combination with this embodiment, the measurement size parameters include but are not limited to the distance L between the center of the auxiliary standard ball 1 and the center of the auxiliary standard ball 3. x , the distance L between the center of the auxiliary standard sphere 2 and the center of the auxiliary standard sphere 4 y , and respectively calculate the deviations between the industrial CT measured values ​​and the calibration values ​​of the corresponding metrological characteristic parameters in step 2, and use the deviations as the calibration values ​​of the length parameters along the X-axis and Y-axis directions of the coordinate system.

[0102] Step S 34 After the scan is completed, use the industrial CT measurement software to measure the distance between the center of the auxiliary standard spheres corresponding to the upper and lower layers along the direction of the line connecting the node sphere and the main standard sphere, and calculate the deviation between the industrial CT measured value and the calibration value of the corresponding metrological characteristic parameter in step S2, and use the deviation as the calibration value of the length parameter along the Z-axis direction of the coordinate system.

[0103] In combination with this embodiment, the measurement size parameters include but are not limited to the distance L between the centers of the auxiliary standard balls corresponding to the upper and lower layers along the line connecting the node ball and the main standard ball. z , and respectively calculate the deviation between the industrial CT measured value and the calibration value of the corresponding metrological characteristic parameter in step S2, and use the deviation as the calibration value of the length parameter along the Z-axis direction of the coordinate system.

[0104] Step S 35 After the scan is completed, use the industrial CT measurement software to measure the distance between the centers of the two balls in the upper and lower layers of auxiliary standard balls, corresponding to the center line passing through the center of the node ball, and calculate the deviation between the industrial CT measured value and the corresponding metrological characteristic parameter calibration value in step S2, and use the deviation as the calibration value of the length parameter along the diagonal direction of the coordinate system space.

[0105] In combination with the present embodiment, the measured dimensional parameters include, but are not limited to, the distance between the centers of the two balls in the upper and lower layers of auxiliary standard balls corresponding to the center line passing through the center of the node ball: the distance d1 between the centers of auxiliary standard ball 1 and auxiliary standard ball 7, the distance d2 between the centers of auxiliary standard ball 2 and auxiliary standard ball 8, the distance d3 between the centers of auxiliary standard ball 3 and auxiliary standard ball 5, and the distance d4 between the centers of auxiliary standard ball 4 and auxiliary standard ball 6. The deviations between the actual measured values ​​of the industrial CT and the calibration values ​​of the corresponding metrological characteristic parameters in step S2 are calculated respectively, and the deviations are used as the calibration values ​​of the length parameters along the diagonal direction of the coordinate system space.

[0106] Step S 36 After the scan is completed, use the industrial CT measurement software to measure the cone angle of the cone formed by the center of the main standard ball and the centers of the upper and lower layers of multiple auxiliary standard balls, and calculate the deviation between the industrial CT measured value and the corresponding metrological characteristic parameter calibration value in step S2, and use the deviation as the cone angle parameter calibration value of the cone.

[0107] In combination with this embodiment, the measured dimensional parameters include, but are not limited to, the cone angles of cone 1 and cone 2 formed by the center of the main standard ball and the centers of the four auxiliary standard balls in the upper and lower layers, respectively, and the deviations between the industrial CT measured values ​​and the corresponding metrological characteristic parameter calibration values ​​in step S2 are calculated respectively, and the deviations are used as the cone angle parameter calibration values ​​of the cone.

[0108] Step S 37 After the scanning is completed, the industrial CT measurement software is used to measure the diameter of the cylinder formed by the centers of multiple auxiliary standard balls, and the deviations between the industrial CT measured values ​​and the corresponding metrological characteristic parameter calibration values ​​in step S2 are calculated respectively, and the deviations are used as the diameter parameter calibration values ​​of the cylinder.

[0109] In combination with this embodiment, the measured dimensional parameters include, but are not limited to, the diameter of the cylinder formed by the centers of the eight auxiliary standard balls, and the deviations between the industrial CT measured values ​​and the corresponding metrological characteristic parameter calibration values ​​in step S2 are calculated respectively, and the deviations are used as the diameter parameter calibration values ​​of the cylinder.

[0110] According to the above description, the calibration method of the dimensional measurement comprehensive parameter calibration ball group target of the present invention can not only calibrate larger dimensional parameters but also realize the calibration of cone and cylinder parameters by one calibration using the comprehensive parameter calibration ball group target. It has a simple structure and is easy to operate and maintain, which is beneficial to improving the calibration efficiency of industrial CT equipment and reducing the calibration cost.

[0111] In summary, the calibration method of the size measurement comprehensive parameter calibration ball set target of the present invention has the following advantages:

[0112] 1. Compared with the forest ball standard, the measuring size of the present invention is larger, and it can provide calibration of the cone and cylinder parameters of industrial CT equipment, thereby improving the accuracy of measuring the cone and cylinder parameters of industrial CT equipment;

[0113] Second, through the new structural design, the present invention can realize one-time metrological calibration of multiple size parameters, replacing the multiple metrological calibrations of traditional forest balls, special cones and cylinder standards, and improving the calibration efficiency of industrial CT equipment;

[0114] 3. The calibration ball target set of the present invention has a simple structure and is easy to use and maintain, and can solve the problem of high maintenance and management costs and difficulty caused by the large variety of size calibration standards currently available for industrial CT equipment.

[0115] For those skilled in the art, the above invention disclosure is only used as an example and does not constitute a limitation of the present application. Although not explicitly stated herein, those skilled in the art may make various modifications, improvements and amendments to the present application. Such modifications, improvements and amendments are suggested in the present application, so such modifications, improvements and amendments still belong to the spirit and scope of the exemplary implementation of the present application.

[0116] At the same time, the present application uses specific words to describe the embodiments of the present application. For example, "one embodiment", "an embodiment", and / or "some embodiments" refer to a certain feature, structure or characteristic related to at least one embodiment of the present application. Therefore, it should be emphasized and noted that "one embodiment" or "an embodiment" or "an alternative embodiment" mentioned twice or more in different positions in this specification does not necessarily refer to the same embodiment. In addition, some features, structures or characteristics in one or more embodiments of the present application can be appropriately combined.

[0117] Although the specific embodiments of the present invention are described above, it should be understood by those skilled in the art that these are only examples, and the protection scope of the present invention is defined by the appended claims. Those skilled in the art may make various changes or modifications to these embodiments without departing from the principles and essence of the present invention, but these changes and modifications all fall within the protection scope of the present invention.

Claims

1. A calibration method for a size measurement comprehensive parameter calibration ball set target, characterized in that: The calibration method comprises the following steps: S1. Design and manufacture dimensional measurement comprehensive parameter calibration ball set targets; S2. Use high-precision calibration standards to calibrate the metrological characteristic parameters of the dimensional measurement comprehensive parameter calibration ball set target; S3. Use the dimensional measurement comprehensive parameter calibration ball target set to calibrate the dimensional parameter measurement capability of the industrial CT equipment for key features.

2. The calibration method of the size measurement comprehensive parameter calibration ball set target according to claim 1, characterized in that: The step S1 includes: S 11 The size measurement comprehensive parameter calibration ball set target includes a main standard ball and multiple auxiliary standard balls; S 12 , the main standard ball and a plurality of auxiliary standard balls are mounted on the node ball through thin rods; S 13 The node ball is mounted on the disc-shaped base via a thin rod.

3. The calibration method of the size measurement comprehensive parameter calibration ball set target according to claim 2, characterized in that: The step S1 also includes: S 14 , a line connecting the center of the main standard sphere and the center of the node sphere is perpendicular to the upper surface of the disc-shaped base; S 15 , the distance between the center of the auxiliary standard sphere and the center of the node sphere is the same, and the center of the auxiliary standard sphere is located on a spherical surface concentric with the node sphere; S 16 , the angle between the line connecting the center of each auxiliary standard sphere and the center of the node sphere is equal to the angle between the line connecting the center of the main standard sphere and the center of the node sphere.

4. The calibration method of the size measurement comprehensive parameter calibration ball set target according to claim 3, characterized in that: The step S1 also includes: S 17 , the auxiliary standard balls include 8 auxiliary standard balls, which are symmetrically distributed in two layers, with 4 auxiliary standard balls distributed in each layer; S 18 The centers of the auxiliary standard balls in each layer are located on the same plane circle and equally divide the plane circle.

5. The calibration method for the size measurement comprehensive parameter calibration ball set target according to claim 1, characterized in that: The metrological characteristic parameters of the size measurement comprehensive parameter calibration ball group target described in step S2 include: the roundness and diameter of the main standard ball and the auxiliary standard ball; the distance between the centers of two non-adjacent auxiliary standard balls in the upper layer; the distance between the centers of the corresponding auxiliary standard balls in the upper and lower layers in the direction of the line connecting the node ball and the center of the main standard ball; the distance between the centers of the two balls in the upper and lower layers of auxiliary standard balls whose corresponding center lines pass through the center of the node ball; the cone angle of the cone formed by the center of the main standard ball and the centers of multiple auxiliary standard balls in the upper and lower layers; and the diameter of the cylinder formed by the centers of multiple auxiliary standard balls.

6. The calibration method of the size measurement comprehensive parameter calibration ball set target according to claim 1, characterized in that: The high-precision calibration standard in step S2 includes a high-precision coordinate measuring machine or a roundness meter; the ratio of the measurement uncertainty of the high-precision coordinate measuring machine to the measurement uncertainty of the calibrated industrial CT equipment is less than or equal to 0.

1.

7. The calibration method for the size measurement comprehensive parameter calibration ball set target according to claim 1, characterized in that: The step S3 comprises: S 31 , place the size measurement comprehensive parameter calibration ball set target on the measuring workbench of the industrial CT equipment, and scan and measure the main standard ball and multiple auxiliary standard balls.

8. The calibration method for the size measurement comprehensive parameter calibration ball set target according to claim 7, characterized in that: The step S 31 The method then includes: after the scanning is completed, using industrial CT measurement software to measure the diameter of the main standard ball, and calculating the deviation between the industrial CT measured value and the calibration value of the corresponding metrological characteristic parameter in step S2, and using the deviation as the calibration value of the ball parameter.

9. The calibration method of the size measurement comprehensive parameter calibration ball set target according to claim 7, characterized in that: The step S 31 It also includes: after the scanning is completed, using industrial CT measurement software to measure the distance between the centers of two non-adjacent balls of the upper auxiliary standard ball, and calculating the deviations between the industrial CT measured value and the calibration value of the corresponding metrological characteristic parameter in step S2, and using the deviations as calibration values ​​of the length parameters along the X-axis and Y-axis directions of the coordinate system.

10. The calibration method of the size measurement comprehensive parameter calibration ball set target according to claim 7, characterized in that: The step S 31 It also includes: after the scanning is completed, using industrial CT measurement software to measure the distance between the center of the auxiliary standard spheres corresponding to the upper and lower layers along the direction of the line connecting the node sphere and the main standard sphere, and calculating the deviation between the industrial CT measured value and the corresponding metrological characteristic parameter calibration value in step S2, and using the deviation as the calibration value of the length parameter along the Z-axis direction of the coordinate system.

11. The calibration method of the size measurement comprehensive parameter calibration ball set target according to claim 7, characterized in that: The step S 31 It also includes: after the scanning is completed, using industrial CT measurement software to measure the distance between the centers of the two balls in the upper and lower layers of auxiliary standard balls, corresponding to the center line passing through the center of the node ball, and calculating the deviation between the industrial CT measured value and the corresponding metrological characteristic parameter calibration value in step S2, and using the deviation as the calibration value of the length parameter along the diagonal direction of the coordinate system space.

12. The calibration method of the size measurement comprehensive parameter calibration ball set target according to claim 7, characterized in that: The step S 31 The method also includes: after the scanning is completed, using industrial CT measurement software to measure the cone angle of the cone formed by the center of the main standard ball and the centers of the upper and lower layers of multiple auxiliary standard balls, and calculating the deviation between the industrial CT measured value and the corresponding metrological characteristic parameter calibration value in step S2, and using the deviation as the cone angle parameter calibration value of the cone.

13. The calibration method of the size measurement comprehensive parameter calibration ball set target according to claim 8, characterized in that: The step S 31 It also includes: after the scanning is completed, using industrial CT measurement software to measure the diameter of the cylinder formed by the centers of multiple auxiliary standard balls, and calculating the deviation between the industrial CT measured value and the corresponding metrological characteristic parameter calibration value in step S2, and using the deviation as the diameter parameter calibration value of the cylinder.

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