System and method for transmitting springback compensation data of scalloped segment part drawing forming die

Abstract

The invention provides a scalloped segment part drawing forming die springback compensation data transmission system and method, and the system comprises a data collection module which collects the point cloud data of the inner molded surface of a scalloped segment real object; the data transmission module is used for transmitting the acquired point cloud data to the modeling module; the modeling module is used for receiving the point cloud data and reversely reconstructing the point cloud data to form a real object scalloped segment model; the springback compensation module is used for comparing the real scalloped segment model with the theoretical scalloped segment model to obtain actual springback data of the scalloped segment; and carrying out reverse compensation on the molded surface of the scalloped segment mold based on the springback data. The compensated mold is used for machining the scalloped segment product, the forming precision of the scalloped segment product can be guaranteed, manual shape correction work is omitted, the overall machining efficiency and reliability of the product are greatly improved, and manpower resources are saved.

Description

Technical Field

[0001] The invention relates to the field of metal plastic forming, and in particular to a springback compensation data transmission system and method for a melon-shaped part drawing die. Background Art

[0002] Melon slice parts are an important curved surface structural part in the tank structure of a launch vehicle. They are usually welded together to form an ellipsoidal tank bottom. This type of part usually uses a deep drawing process to form the part profile, and the final geometric features of the part are formed after trimming and springback. In the middle, the product is heat treated and strengthened by quenching and artificial aging. The current main process flow adopts "deep drawing + trimming + hot pressing correction + quenching + manual correction". The main defects of this type of part forming process are surface wrinkling, cracking and springback. The wrinkling and cracking problems can currently be solved by adjusting the structure of the deep drawing die and the deep drawing process parameters, but the quenching heat treatment and trimming springback of the parts are inevitable, resulting in a large workload for part correction. With the increase in model development tasks and reliability requirements in the aerospace field, it is necessary to consider process factors such as springback, reversely compensate the part springback on the die profile, and perform deep drawing on the quenched sheet to achieve fast and precise forming. Summary of the invention

[0003] In view of the defects in the prior art, the object of the present invention is to provide a data transmission system and method for springback compensation of a deep drawing die for melon peel parts.

[0004] According to the present invention, a springback compensation data transmission system for a melon peel part drawing die is provided, comprising: Data acquisition module, collecting point cloud data of the inner surface of the melon slice; Data transmission module, which transmits the collected point cloud data to the modeling module; The modeling module receives the point cloud data and reversely reconstructs the point cloud data to form a physical melon slice model.

[0005] Preferably, it also includes a springback compensation module for comparing the physical melon slice model with the theoretical melon slice model to obtain actual springback data of the melon slice; and reversely compensate the melon slice mold surface based on the springback data.

[0006] Preferably, the modeling module includes: Extract the inner surface of the theoretical melon slice model and divide the surface equally along the longitude and latitude to form equal points P i,j (x, y, z); the normal vector V of the equally divided point i,j Perpendicular to the melon-shaped surface, and set the direction inside the surface as the positive direction; For the trimmed melon slice parts, find the points on the actual object that correspond to the theoretical melon slice model and make reference holes; use 3D scanning equipment to digitally scan and measure the inner surface of the formed part to obtain the point cloud data of the inner surface of the part; use 3D software to reversely reconstruct the point cloud data to form a reconstructed melon slice physical surface.

[0007] Preferably, the springback compensation module includes aligning the theoretical profile with the physical profile at a certain point and its normal vector; comparing the theoretical melon segment model with the physical melon segment model, calculating the springback amount of each discrete point on the theoretical profile from the normal direction of the surface at that point to the point on the physical profile, and obtaining the springback data of each discrete point. S i，j : S i，j =\ W i,j -P i，j \ ; Among them, W i,j is a point on the physical surface, P i，j are discrete points on the theoretical surface.

[0008] Preferably, the rebound compensation module further includes a method for compensating the rebound data of each discrete point. S i，j , calculate the springback amount of each discrete segment; Assume the rebound compensation coefficient of each discrete point is k i，j , then the compensation point is: P ’ i，j= P i，j -k i，j ×V i,j × S i，j ; The compensated points are spliced ​​using spline curves in CATIA software, and the spliced ​​multiple spline lines are reconstructed through multi-section surfaces to obtain the compensated melon segment inner surface.

[0009] Preferably, the point cloud data is acquired by scanning the inner surface of the actual melon slice with a non-contact measuring device; the compensated melon slice inner surface is supplemented with technology according to the actual mold design requirements to complete the compensation process.

[0010] According to the present invention, a method for transmitting data of springback compensation for a deep drawing die of a melon-shaped part is provided, comprising: Data collection step, collecting point cloud data of the inner surface of the melon slice; Data transmission step, transmitting the collected point cloud data; The modeling step is to receive the point cloud data and reversely reconstruct the point cloud data to form a physical melon slice model.

[0011] Preferably, the method further includes a springback compensation step for comparing the physical melon slice model with the theoretical melon slice model to obtain actual springback data of the melon slice; and reversely compensating the melon slice mold surface based on the springback data.

[0012] Preferably, the modeling step comprises: Extract the inner surface of the theoretical melon slice model and divide the surface equally along the longitude and latitude to form equal points P i,j (x, y, z); the normal vector V of the equally divided point i,j Perpendicular to the melon-shaped surface, and set the direction inside the surface as the positive direction; For the trimmed melon slice parts, find the points on the actual object that correspond to the theoretical melon slice model and make reference holes; use 3D scanning equipment to digitally scan and measure the inner surface of the formed part to obtain the point cloud data of the inner surface of the part; use 3D software to reversely reconstruct the point cloud data to form a reconstructed melon slice physical surface.

[0013] Preferably, the springback compensation step includes aligning the theoretical profile with the physical profile at a certain point and its normal vector; comparing the theoretical melon segment model with the physical melon segment model, calculating the springback amount of each discrete point on the theoretical profile from the normal direction of the surface at that point to the point on the physical profile, and obtaining the springback data of each discrete point. S i，j : S i，j =\ W i,j -P i，j \ ; Among them, W i,j is a point on the physical surface, P i，j are discrete points on the theoretical surface.

[0014] Preferably, the springback compensation step further comprises: S i，j , calculate the springback amount of each discrete segment; Assume the rebound compensation coefficient of each discrete point is k i，j , then the compensation point is: P ’ i，j= P i，j -k i，j ×V i,j × S i，j ; The compensated points are spliced ​​using spline curves in CATIA software, and the spliced ​​multiple spline lines are reconstructed through multi-section surfaces to obtain the compensated melon segment inner surface.

[0015] Preferably, the point cloud data is acquired by scanning the inner surface of the actual melon slice with a non-contact measuring device; the compensated melon slice inner surface is supplemented with technology according to the actual mold design requirements to complete the compensation process.

[0016] Compared with the prior art, the present invention has the following beneficial effects: 1. The present invention adopts a non-contact measuring device to scan the inner surface of the actual melon slice to obtain a point cloud, and uses three-dimensional software to reversely reconstruct the point cloud data to form a physical melon slice model. By comparing the physical melon slice model with the theoretical model, the actual springback data of the melon slice is obtained, and the melon slice mold surface is reversely compensated based on the springback data. It can realize fast and accurate forming of the quenched plate and has good practicality.

[0017] 2. The present invention adopts a compensated mold to process melon slice products, which can ensure their forming accuracy, eliminate manual shaping work, greatly improve the overall processing efficiency and reliability of the product, and save human resources.

[0018] Other beneficial effects of the present invention will be explained in the specific implementation manner through the introduction of specific technical features and technical solutions. Through the introduction of these technical features and technical solutions, those skilled in the art should be able to understand the beneficial technical effects brought about by the technical features and technical solutions. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Other features, objects and advantages of the present invention will become more apparent from the detailed description of non-limiting embodiments made with reference to the following drawings: Figure 1 The figure is a flow chart of the method of the present invention.

[0020] Figure 2 This is a schematic diagram of the box bottom component product.

[0021] Figure 3 This is a schematic diagram of the theoretical inner surface of the melon slice part at the bottom of the box.

[0022] Figure 4 This is the theoretical surface discrete diagram of the melon slice part.

[0023] Figure 5 This is a schematic diagram of the inner surface of the melon segment after 3D scanning.

[0024] Figure 6 This is a comparison diagram between the scanned actual surface and the theoretical surface.

[0025] Figure 7 This is a schematic diagram of melon slice compensation and mold design. DETAILED DESCRIPTION

[0026] The present invention is described in detail below in conjunction with specific embodiments. The following embodiments will help those skilled in the art to further understand the present invention, but are not intended to limit the present invention in any form. It should be noted that, for those of ordinary skill in the art, several changes and improvements can also be made without departing from the concept of the present invention. These all belong to the protection scope of the present invention.

[0027] Example 1 Reference Figure 1 As shown, a method for transmitting data of springback compensation of a deep drawing die for melon peel parts comprises: Step 1: Discrete the melon slice surface; Reference Figure 4 As shown in the figure, it is the inner surface of the box bottom melon wedge part with a major semi-axis of 1892 and a minor semi-axis of 1182.5; L i are discrete meridians, P i，j is a discrete point, V i，j is the normal vector of the discrete point on the surface. Extract the inner surface of the melon slice theoretical model, divide the surface into 10 equal parts along the longitude and latitude directions, and form equal division points P i,j (x,y,z)(i=1,2…11;j=1,2…11), normal vector V of the equally divided point i,j (i=1,2…11;j=1,2…11) are perpendicular to the melon slice surface, the direction is inward of the surface as the positive direction, and the bisectors from left to right are L1, L2, L3…L 11 , the equal points from the upper left to the lower right are P 1，1 , P 1，2 …P i，j …P 11，10 , P 11，11 .

[0028] Step 2: Non-contact 3D measurement of melon slice surface; Reference Figure 5 and Figure 6 As shown in the figure, for the cut melon slice part, find the P corresponding to the theoretical model in the real object. 6，1 , P 6，6 , P 6，11 Points are made at 3 points, 2.5 holes are made as reference holes, and 3D scanning equipment is used to digitally scan and measure the inner surface of the formed part to obtain the point cloud data of the inner surface of the part (including the reference hole position). The point cloud data is reversely reconstructed using general 3D software to form a reconstructed melon slice physical surface.

[0029] Step 3: Surface comparison and springback calculation; Reference Figure 6 As shown, the theoretical surface and the actual surface are connected at point P 6，6 and V on the normal vector 6，6Overlap, in L 6 coplanar; among them W i,j V is the normal vector of the theoretical model on the physical model. i，j The intersection of is the springback point. By comparing the theoretical model with the actual measurement reconstruction model, the theoretical surface of each discrete point P is calculated. i，j The surface normal direction V at this point i,j Go to point W on the physical surface i,j Rebound amount, the rebound data of each discrete point is: S i，j =\ W i,j -P i，j \ .

[0030] Step 4: Springback compensation; According to the part springback geometry data S i，j , calculate the rebound amount of each discrete segment, and set the rebound compensation coefficient of each discrete point to be k i，j Set to 1, the compensation point is P ’ i，j= P i，j -k×V i，j ×S i，j , the compensated points are spliced ​​using spline curves in CATIA software, and the spliced ​​multiple spline lines L ’ i Through multi-section surface reconstruction, the inner surface of the melon slice after compensation is obtained. Table 3 is the rebound measurement data table: Table 3 Rebound measurement data Table S i，j

[0031] Step 5: Compensation mold design; Reference Figure 7 As shown, the inner surface of the melon slice after compensation is supplemented with process according to the actual mold design requirements, and finally the compensation design of the mold is realized.

[0032] The present invention adopts the compensated mold to process the melon slice product, which can ensure the forming accuracy, eliminate the manual shape adjustment work, greatly improve the overall processing efficiency and reliability of the product, and save human resources.

[0033] Example 2 A springback compensation data transmission system for deep drawing forming dies of melon peel parts, comprising: Data acquisition module, collecting point cloud data of the inner surface of the melon slice; Data transmission module, which transmits the collected point cloud data to the modeling module; The modeling module receives the point cloud data and reversely reconstructs the point cloud data to form a physical melon slice model.

[0034] It also includes a springback compensation module, which is used to compare the physical melon slice model with the theoretical melon slice model to obtain the actual springback data of the melon slice; and reversely compensate the melon slice mold surface based on the springback data.

[0035] The modeling module includes: Extract the inner surface of the theoretical melon slice model and divide the surface equally along the longitude and latitude to form equal points P i,j (x, y, z); the normal vector V of the equally divided point i,j Perpendicular to the melon-shaped surface, and set the direction inside the surface as the positive direction; For the trimmed melon slice parts, find the points on the actual object that correspond to the theoretical melon slice model and make reference holes; use 3D scanning equipment to digitally scan and measure the inner surface of the formed part to obtain the point cloud data of the inner surface of the part; use 3D software to reversely reconstruct the point cloud data to form a reconstructed melon slice physical surface.

[0036] The springback compensation module includes aligning the theoretical profile with the physical profile at a certain point and its normal vector; comparing the theoretical melon slice model with the physical melon slice model, calculating the springback amount of each discrete point on the theoretical profile from the normal direction of the surface at that point to the point on the physical profile, and obtaining the springback data of each discrete point. S i，j : S i，j =\ W i,j -P i，j \ ; Among them, W i,j is a point on the physical surface, P i，j are discrete points on the theoretical surface.

[0037] The springback compensation module also includes a springback data according to each discrete point S i，j , calculate the springback amount of each discrete segment; Assume the rebound compensation coefficient of each discrete point is k i，j , then the compensation point is: P ’ i，j= P i，j -k i，j ×V i,j × S i，j ; The compensated points are spliced ​​using spline curves in CATIA software, and the spliced ​​multiple spline lines are reconstructed through multi-section surfaces to obtain the compensated melon segment inner surface.

[0038] The point cloud data is acquired based on scanning the inner surface of the actual melon slice by a non-contact measuring device; the compensated melon slice inner surface is supplemented with technology according to the actual mold design requirements to complete the compensation process.

[0039] Those skilled in the art know that, in addition to realizing the system and its various devices, modules, and units provided by the present invention in a purely computer-readable program code, it is entirely possible to realize the same functions in the form of logic gates, switches, application-specific integrated circuits, programmable logic controllers, and embedded microcontrollers by logically programming the method steps. Therefore, the system and its various devices, modules, and units provided by the present invention can be considered as a hardware component, and the devices, modules, and units included therein for realizing various functions can also be regarded as structures within the hardware component; the devices, modules, and units for realizing various functions can also be regarded as both software modules for realizing the method and structures within the hardware component.

[0040] In the description of the present application, it should be understood that the terms "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.

[0041] The above describes the specific embodiments of the present invention. It should be understood that the present invention is not limited to the above specific embodiments, and those skilled in the art can make various changes or modifications within the scope of the claims, which does not affect the essence of the present invention. In the absence of conflict, the embodiments of the present application and the features in the embodiments can be combined with each other arbitrarily.

Claims

1. A springback compensation data transmission system for deep drawing die of melon peel parts, characterized in that: include: Data acquisition module, collecting point cloud data of the inner surface of the melon slice; Data transmission module, which transmits the collected point cloud data to the modeling module; A modeling module receives point cloud data and reversely reconstructs the point cloud data to form a physical melon slice model; The springback compensation module is used to compare the physical melon slice model with the theoretical melon slice model to obtain the actual springback data of the melon slice; and reversely compensate the melon slice mold surface based on the springback data.

2. The springback compensation data transmission system for deep drawing die of melon peel parts according to claim 1 is characterized in that: The modeling module includes: Extract the inner surface of the theoretical melon slice model and divide the surface equally along the longitude and latitude to form equal points P i,j (x, y, z); the normal vector V of the equally divided point i,j Perpendicular to the melon-shaped surface, and set the direction inside the surface as the positive direction; For the trimmed melon slice parts, find the points on the actual object that correspond to the theoretical melon slice model and make reference holes; use 3D scanning equipment to digitally scan and measure the inner surface of the formed part to obtain the point cloud data of the inner surface of the part; use 3D software to reversely reconstruct the point cloud data to form a reconstructed melon slice physical surface.

3. The springback compensation data transmission system for deep drawing die of melon peel parts according to claim 2 is characterized in that: The springback compensation module includes aligning the theoretical profile with the physical profile at a certain point and its normal vector; comparing the theoretical melon slice model with the physical melon slice model, calculating the springback amount of each discrete point on the theoretical profile from the normal direction of the surface at that point to the point on the physical profile, and obtaining the springback data of each discrete point. S i，j : S i，j =\ W i,j -P i，j \ ; Among them, W i,j is a point on the physical surface, P i，j are discrete points on the theoretical surface.

4. The springback compensation data transmission system for deep drawing die of melon peel parts according to claim 3 is characterized in that: The springback compensation module also includes a springback data according to each discrete point S i，j , calculate the springback amount of each discrete segment; Assume the rebound compensation coefficient of each discrete point is k i，j , then the compensation point is: P ’ i，j= P i，j -k i，j ×V i,j × S i，j ; The compensated points are spliced ​​using spline curves in CATIA software, and the spliced ​​multiple spline lines are reconstructed through multi-section surfaces to obtain the compensated melon segment inner surface.

5. The springback compensation data transmission system for deep drawing die of melon peel parts according to claim 3 is characterized in that: The point cloud data is acquired based on scanning the inner surface of the actual melon slice by a non-contact measuring device; the compensated melon slice inner surface is supplemented with technology according to the actual mold design requirements to complete the compensation process.

6. A method for transmitting data of springback compensation for deep drawing die of melon peel parts, characterized in that: include: Data collection step, collecting point cloud data of the inner surface of the melon slice; Data transmission step, transmitting the collected point cloud data; Modeling step: receiving point cloud data and reversely reconstructing the point cloud data to form a physical melon slice model; The springback compensation step is used to compare the physical melon slice model with the theoretical melon slice model to obtain the actual springback data of the melon slice; and reversely compensate the melon slice mold surface based on the springback data.

7. The method for transmitting data of springback compensation for deep drawing die of melon peel parts according to claim 6, characterized in that: The modeling steps include: Extract the inner surface of the theoretical melon slice model and divide the surface equally along the longitude and latitude to form equal points P i,j (x, y, z); the normal vector V of the equally divided point i,j Perpendicular to the melon-shaped surface, and set the direction inside the surface as the positive direction; For the trimmed melon slice parts, find the points on the actual object that correspond to the theoretical melon slice model and make reference holes; use 3D scanning equipment to digitally scan and measure the inner surface of the formed part to obtain the point cloud data of the inner surface of the part; use 3D software to reversely reconstruct the point cloud data to form a reconstructed melon slice physical surface.

8. The method for transmitting data of springback compensation for deep drawing die of melon peel parts according to claim 7, characterized in that: The springback compensation step includes aligning the theoretical profile with the physical profile at a certain point and its normal vector; comparing the theoretical melon segment model with the physical melon segment model, calculating the springback amount of each discrete point on the theoretical profile from the normal direction of the surface at that point to the point on the physical profile, and obtaining the springback data of each discrete point. S i，j : S i，j =\ W i,j -P i，j \ ; Among them, W i,j is a point on the physical surface, P i，j are discrete points on the theoretical surface.

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