A turning workpiece modeling and dynamic updating method for ultra-precision turning

Abstract

The application discloses a turning workpiece modeling and dynamic updating method for ultra-precision turning, and belongs to the technical field of numerical control machining simulation and digital twin manufacturing. The method firstly acquires initial geometric parameters of a turning blank, divides the blank into a plurality of sequentially arranged discrete layers along a workpiece spindle direction according to a blank length and an axial layering thickness, and establishes corresponding layer data; in a simulation running process, a tool path point is periodically received and a possible intersecting discrete layer interval is determined, intersection determination and contour parameter updating are performed on the discrete layers in the interval, and finally, the current workpiece topography is locally reconstructed according to the updated parameters. The method fully utilizes the characteristics of the turning workpiece rotary body, reduces redundant calculation caused by global reconstruction, improves the dynamic updating efficiency of the workpiece topography, and is suitable for the real-time simulation scene of ultra-precision turning.

Description

Technical Field

[0001] This invention belongs to the field of CNC machining simulation and digital twin manufacturing technology, specifically a method for modeling and dynamically updating turned workpieces for ultra-precision turning. Background Technology

[0002] In ultra-precision turning scenarios, tool path accuracy, workpiece morphology evolution, and the visualization of machining results directly impact machining process analysis, condition monitoring, and machining quality assessment. Therefore, it is necessary to model and dynamically update the workpiece morphology in real time during machining to accurately reflect the workpiece's gradual evolution as the tool moves in virtual space.

[0003] In simulation systems, the way a workpiece model is represented directly affects the efficiency and accuracy of material removal calculations, dynamic morphology updates, and visualization. Existing workpiece models do not strike a good balance between accuracy and efficiency, making it difficult to meet ultra-precision requirements: models that pursue high accuracy will perform a unified traversal, material removal calculation, or overall reconstruction of the entire workpiece model in each cycle, resulting in high computational load, high resource consumption, and high update latency. They are mostly used in offline scenarios and cannot meet real-time requirements. Summary of the Invention

[0004] To address the aforementioned shortcomings, this invention provides a method for modeling and dynamically updating turned workpieces for ultra-precision turning.

[0005] The technical solution adopted by the present invention to achieve the above objectives is as follows:

[0006] A method for modeling and dynamically updating turned workpieces for ultra-precision turning includes the following steps:

[0007] Obtain the initial geometric parameters of the turning blank workpiece, divide the blank workpiece into multiple discrete layers according to the geometric parameters, and construct a set of discrete layer parameters;

[0008] Based on the coordinate parameters of the current tool trajectory point and the discrete layer coordinate parameters of the workpiece spindle direction, determine the candidate discrete layer interval corresponding to the current tool trajectory point;

[0009] Within the candidate discrete layer interval, the tool trajectory points are intersected with the parameters of the layer they belong to, and then the parameters of that layer are updated.

[0010] The workpiece shape is locally reconstructed based on the updated parameters, and the entire process is executed periodically to achieve dynamic updating of the workpiece shape during turning.

[0011] The initial geometric parameters of the turned blank workpiece include: blank length, blank radius, workpiece spindle direction, and axial layer thickness.

[0012] The process of dividing the workpiece blank into multiple discrete layers based on geometric parameters is specifically as follows:

[0013] Based on the initial geometric parameters of the blank length and axial layer thickness, the blank length is divided into equal thicknesses according to the preset axial layer thickness to obtain multiple discrete layers arranged in sequence. For each discrete layer, layer parameters are established, which include at least the layer number, axial position and contour boundary parameters, forming an ordered set of layers along the main axis of the workpiece.

[0014] When the turning blank is a cylindrical blank, the blank radius is used as the initial contour boundary parameter of each discrete layer, so that each discrete layer has the same outer contour boundary in the initial state.

[0015] The parameters of this layer are updated based on the intersection criteria, specifically as follows:

[0016] When the corresponding discrete layer does not intersect with the tool, the contour boundary parameters of the discrete layer remain unchanged. When the corresponding discrete layer intersects with the tool, the contour boundary parameters of the discrete layer are updated according to the cutting boundary of the tool at the corresponding position of the discrete layer. The contour boundary parameters are radius parameters or boundary position parameters that represent the local geometric state of the corresponding discrete layer.

[0017] A system for modeling and dynamically updating turned workpieces for ultra-precision turning includes:

[0018] The discrete layer parameter set construction module is used to obtain the initial geometric parameters of the turning blank workpiece, divide the blank workpiece into multiple discrete layers according to the geometric parameters, and construct the discrete layer parameter set.

[0019] The candidate discrete layer interval determination module is used to determine the candidate discrete layer interval corresponding to the current tool trajectory point based on the coordinate parameters of the current tool trajectory point and the discrete layer coordinate parameters of the workpiece spindle direction.

[0020] The layer parameter update module is used to determine the intersection between the tool trajectory points and the parameters of the layer they belong to, layer by layer, within the candidate discrete layer interval, and then update the parameters of that layer.

[0021] The workpiece reconstruction module is used to locally reconstruct the current workpiece shape based on the updated parameters, and periodically execute all steps to achieve dynamic updating of the workpiece shape during the turning process.

[0022] A device for modeling and dynamically updating turning workpieces for ultra-precision turning includes a memory and a processor; the memory is used to store a computer program; the processor is used to implement the method for modeling and dynamically updating turning workpieces for ultra-precision turning when the computer program is executed.

[0023] A computer-readable storage medium storing a computer program that, when executed by a processor, implements the aforementioned method for modeling and dynamically updating turning workpieces for ultra-precision turning.

[0024] The present invention has the following beneficial effects and advantages:

[0025] 1. This invention makes full use of the rotating features of the turned workpiece and adopts a layered discrete structure along the main axis of the workpiece to express the workpiece morphology, which reduces the complexity of the model organization while ensuring the ability to express local contours.

[0026] 2. This invention quickly determines candidate discrete layer intervals by using the current tool position, and only processes the local layer units where the tool is actually applied, avoiding repeated calculations of unchanged areas, which helps to improve real-time update efficiency.

[0027] 3. The present invention can adjust the axial layer thickness according to the required accuracy and efficiency, which facilitates engineering applications in different turning simulation tasks. Attached Figure Description

[0028] Figure 1 This is a flowchart of the overall process of the present invention;

[0029] Figure 2 This is a schematic diagram of a layered discrete workpiece model;

[0030] Figure 3 This is a schematic diagram of localized material removal and workpiece morphology update. Detailed Implementation

[0031] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments.

[0032] like Figure 1 As shown, a method for modeling and dynamically updating turned workpieces for ultra-precision turning includes the following steps:

[0033] Obtain the initial geometric parameters of the turning blank, wherein the initial geometric parameters include at least the blank length, blank radius, workpiece spindle direction, and axial layer thickness;

[0034] Based on the blank length and axial layer thickness, the blank is divided into multiple discrete layers arranged in sequence along the main axis of the workpiece, and layer data containing at least layer number, axial position and contour boundary parameters is established for each discrete layer, forming an ordered set of layers along the workpiece direction.

[0035] The cycle is determined based on the current tool path point, the tool axial width, and the axial layer thickness to determine the current corresponding candidate discrete layer interval;

[0036] For each discrete layer in the candidate discrete layer interval, the intersection between the tool and the workpiece is determined layer by layer. When the corresponding discrete layer does not intersect with the tool, the contour boundary parameters of the discrete layer remain unchanged. When the corresponding discrete layer intersects with the tool, the contour boundary parameters of the discrete layer are updated according to the cutting boundary of the tool at the corresponding position of the discrete layer.

[0037] The workpiece shape at the current moment is locally reconstructed based on the updated discrete layer contour boundary parameters, and the process is executed cyclically according to the tool trajectory points to achieve dynamic updating of the workpiece shape during turning.

[0038] Furthermore, the method of dividing the blank into multiple sequentially arranged discrete layers along the main axis of the workpiece is as follows: the blank length is divided into equal-thickness sections according to a preset axial layer thickness to obtain the number of discrete layers, and a position index relationship corresponding one-to-one with the actual axial coordinates is established for each discrete layer.

[0039] When the turning blank is a cylindrical blank, the blank radius is used as the initial contour boundary parameter of each discrete layer, so that each discrete layer has the same outer contour boundary in the initial state.

[0040] The candidate discrete layer interval is determined by the position of the current tool trajectory point in the workpiece spindle direction, so as to convert the current working range of the tool into a local layer interval in the workpiece spindle direction.

[0041] The determination of the intersection between the tool trajectory point and the workpiece, as well as the updating of the contour parameters, are performed only within the candidate discrete layer interval, avoiding global traversal and unified reconstruction of the entire workpiece model.

[0042] The contour boundary parameter is a radius parameter or boundary position parameter that represents the local geometric state of the corresponding discrete layer.

[0043] Within each update cycle, after updating the contour boundary parameters of the candidate discrete layer intervals, the workpiece shape at the current moment is locally reconstructed based on the updated layer parameters.

[0044] Example

[0045] In the embodiments, such as Figure 2 As shown, a layered discrete model is established for a cylindrical turning blank. First, the blank length L, blank radius R, workpiece spindle direction, and axial layer thickness Δz are obtained. Based on L and Δz, the number N of discrete layers along the workpiece spindle direction is calculated, and the blank is divided into N sequentially arranged discrete layers along the workpiece spindle direction. For each discrete layer, the layer number i and the corresponding axial position Z are recorded. i and the contour boundary parameter r i For a cylindrical initial blank, each discrete layer has the same outer contour boundary in the initial state, therefore r iThe initial values ​​of all are set to R. This establishes an ordered sequence set along the main axis of the workpiece, completing the initialization of the workpiece model.

[0046] like Figure 3 As shown, during the simulation, the system periodically reads the tool trajectory points sequentially. Let the current tool trajectory point be Z in the workpiece spindle direction. t If the width of the tool in the axial direction is w, then according to Z t The parameters w and Δz determine the candidate discrete layer intervals that the current tool position may affect. Then, the discrete layers within the interval are intersected layer by layer: if the tool does not intersect with a certain discrete layer, the original contour boundary parameters of the discrete layer are kept unchanged; if the tool intersects with a certain discrete layer, the contour boundary parameters of the discrete layer are updated according to the cutting boundary formed by the tool at the position of the discrete layer.

[0047] After the update is complete, the system reconstructs the current workpiece shape based on the new set of layer parameters. Since parameter modifications are only performed on candidate discrete layer intervals, there is no need to perform a global reconstruction of the entire workpiece model in each cycle, thus reducing the overhead of model updates. As the tool moves, the system periodically repeats the above process, eventually causing the workpiece to gradually evolve from its initial blank state to the machined target shape.

Claims

1. A method for modeling and dynamically updating turned workpieces for ultra-precision turning, characterized in that, Includes the following steps: Obtain the initial geometric parameters of the turning blank workpiece, divide the blank workpiece into multiple discrete layers according to the geometric parameters, and construct a set of discrete layer parameters; Based on the coordinate parameters of the current tool trajectory point and the discrete layer coordinate parameters of the workpiece spindle direction, determine the candidate discrete layer interval corresponding to the current tool trajectory point; Within the candidate discrete layer interval, the tool trajectory points are intersected with the parameters of the layer they belong to, and then the parameters of that layer are updated. The workpiece shape is locally reconstructed based on the updated parameters, and the entire process is executed periodically to achieve dynamic updating of the workpiece shape during turning.

2. The method for modeling and dynamically updating turned workpieces for ultra-precision turning according to claim 1, characterized in that, The initial geometric parameters of the turned blank workpiece include: blank length, blank radius, workpiece spindle direction, and axial layer thickness.

3. The method for modeling and dynamically updating turned workpieces for ultra-precision turning according to claim 1, characterized in that, The process of dividing the blank workpiece into multiple discrete layers based on geometric parameters is specifically as follows: Based on the initial geometric parameters of the blank length and axial layer thickness, the blank length is divided into equal thicknesses according to the preset axial layer thickness to obtain multiple discrete layers arranged in sequence. For each discrete layer, layer parameters are established, which include at least the layer number, axial position and contour boundary parameters, forming an ordered set of layers along the main axis of the workpiece.

4. The method for modeling and dynamically updating turned workpieces for ultra-precision turning according to claim 1, characterized in that, When the turning blank is a cylindrical blank, the blank radius is used as the initial contour boundary parameter of each discrete layer, so that each discrete layer has the same outer contour boundary in the initial state.

5. The method for modeling and dynamically updating turned workpieces for ultra-precision turning according to claim 1, characterized in that, The parameters of this layer are updated based on the intersection criteria, specifically as follows: When the corresponding discrete layer does not intersect with the tool, the contour boundary parameters of the discrete layer remain unchanged. When the corresponding discrete layer intersects with the tool, the contour boundary parameters of the discrete layer are updated according to the cutting boundary of the tool at the corresponding position of the discrete layer. The contour boundary parameters are radius parameters or boundary position parameters that represent the local geometric state of the corresponding discrete layer.

6. A modeling and dynamic updating system for machined workpieces in ultra-precision turning, characterized in that, include: The discrete layer parameter set construction module is used to obtain the initial geometric parameters of the turning blank workpiece, divide the blank workpiece into multiple discrete layers according to the geometric parameters, and construct the discrete layer parameter set. The candidate discrete layer interval determination module is used to determine the candidate discrete layer interval corresponding to the current tool trajectory point based on the coordinate parameters of the current tool trajectory point and the discrete layer coordinate parameters of the workpiece spindle direction. The layer parameter update module is used to determine the intersection between the tool trajectory points and the parameters of the layer they belong to, layer by layer, within the candidate discrete layer interval, and then update the parameters of that layer. The workpiece reconstruction module is used to locally reconstruct the current workpiece shape based on the updated parameters, and periodically execute all steps to achieve dynamic updating of the workpiece shape during the turning process.

7. A device for modeling and dynamically updating turned workpieces for ultra-precision turning, characterized in that, It includes a memory and a processor; the memory is used to store a computer program; the processor is used to implement, when executing the computer program, a method for modeling and dynamically updating turning workpieces for ultra-precision turning as described in any one of claims 1-5.

8. A computer-readable storage medium, characterized in that, The storage medium stores a computer program, which, when executed by a processor, implements a method for modeling and dynamically updating turning workpieces for ultra-precision turning as described in any one of claims 1-5.

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