Layered cutting machining parameter control method and system

Abstract

The invention discloses a layered cutting machining parameter control method and system, and relates to the technical field of device machining, the method comprises the steps that a heat sensitive workpiece is layered, an upper machining layer and a lower machining layer are obtained, and the heat dissipation capacity of the lower machining layer is lower than that of the upper machining layer; the to-be-machined area of the lower machining layer is divided into a plurality of discrete machining units; a machining sequence is generated, the machining sequence is a sequence for cutting the multiple discrete machining units, and the discrete machining units corresponding to two adjacent cutting operations in the machining sequence are not adjacent in space; and according to the machining sequence, cutting machining parameter control is conducted on the multiple discrete machining units. Layered cutting machining parameter control can be achieved in combination with different machining sequences, and the product quality and reliability are improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of device processing, and in particular to a layered cutting processing parameter control method and system. BACKGROUND

[0002] In the field of modern precision manufacturing, when processing a heat-sensitive metal workpiece with a complex deep cavity structure, the traditional method is to continuously cut the heat-sensitive metal workpiece according to the contour path. However, when processing from the shallow layer to the deep layer, the processing environment will change dramatically, especially the deterioration of cooling and chip removal conditions, which can have unexpected negative effects on the microstructure and mechanical properties of the workpiece material. The inconsistent conditions between the shallow layer and the deep layer introduce performance defects at the interlayer junction, which is a hidden and unpredictable quality problem, affecting the service life and reliability of the product, and the product quality and reliability are low.

[0003] To sum up, the technical problems in the related art need to be improved. SUMMARY

[0004] The main purpose of the embodiments of the present application is to provide a layered cutting processing parameter control method and system, which can realize layered cutting processing parameter control combined with different processing sequences, thereby improving the product quality and reliability.

[0005] In one aspect, the present application provides a layered cutting processing parameter control method, comprising the following steps: Layering the heat-sensitive workpiece to obtain an upper processing layer and a lower processing layer, the heat dissipation capacity of the lower processing layer being lower than that of the upper processing layer; Dividing the to-be-processed area of the lower processing layer into a plurality of discrete processing units; Generating a processing sequence, the processing sequence being the sequence of cutting the plurality of discrete processing units, and the discrete processing units corresponding to two adjacent cutting operations in the processing sequence being spatially non-adjacent; According to the processing sequence, the plurality of discrete processing units are subjected to cutting processing parameter control.

[0006] In some embodiments, the cutting processing parameter control of the plurality of discrete processing units according to the processing sequence comprises: According to the processing sequence, setting an energy injection limit; Collecting the power consumption value of the spindle drive motor at intervals of a preset collection time; Controlling the energy cumulative value of a single cutting operation of the discrete processing unit to be less than the energy injection limit, the energy cumulative value being calculated according to the power consumption value.

[0007] In some embodiments, the controlling, according to the machining sequence, the cutting machining parameter of the plurality of discrete machining units comprises: controlling, according to the machining sequence, a single cutting time of the discrete machining unit to be less than or equal to a first preset time threshold; controlling, according to the machining sequence, a time interval between adjacent cutting operations of the discrete machining unit to be greater than or equal to a second preset time threshold.

[0008] In some embodiments, the controlling, according to the machining sequence, the time interval between adjacent cutting operations of the discrete machining unit to be greater than or equal to a second preset time threshold comprises: calculating, according to the machining sequence, a total duration of cutting other machining units in the time interval; if the total duration is less than the second preset time threshold, calculating a time difference according to the total duration and the second preset time threshold; generating, according to the time difference, a non-cutting machine tool motion path, an execution duration of the non-cutting machine tool motion path being equal to the time difference; executing the non-cutting machine tool motion path.

[0009] In some embodiments, the generating, according to the time difference, the non-cutting machine tool motion path comprises: constructing a kinematic characteristic constraint of the non-cutting machine tool motion path, the kinematic characteristic constraint being used to suppress structural vibration caused by machine tool motion; generating, according to the time difference and the kinematic characteristic constraint, a geometric shape and speed curve of the non-cutting machine tool motion path; generating the non-cutting machine tool motion path according to the geometric shape and speed curve.

[0010] In some embodiments, the generating, according to the time difference and the kinematic characteristic constraint, the geometric shape and speed curve of the non-cutting machine tool motion path comprises: obtaining geometric information of the heat-sensitive workpiece in a machining space; generating, according to the geometric information, a boundary condition, the boundary condition being used to constrain the geometric shape of the non-cutting machine tool motion path; generating, according to the time difference, the kinematic characteristic constraint and the boundary condition, the geometric shape and speed curve of the non-cutting machine tool motion path.

[0011] In some embodiments, the constructing the kinematic characteristic constraint of the non-cutting machine tool motion path comprises: acquiring first position information within a machine tool workspace and second position information of a non-cutting machine tool movement path; constructing a target correspondence between the first position information and a target kinematic feature, the target kinematic feature being used to suppress structural vibration; constructing the kinematic feature constraint according to the second position information and the target correspondence.

[0012] In some embodiments, the constructing the target correspondence between the first position information and a target kinematic feature comprises: constructing an initial correspondence between the first position information and a target kinematic feature; acquiring actual vibration information when the machine tool executes a movement path at a target position, the first position information containing the target position; determining an associated kinematic feature according to the target position and the initial correspondence; determining a vibration reference according to the associated kinematic feature; updating the associated kinematic feature if the actual vibration information exceeds the vibration reference; updating the initial correspondence according to the updated associated kinematic feature to obtain the target correspondence.

[0013] In some embodiments, the updating the associated kinematic feature comprises: calculating a deviation amount according to the actual vibration information and the vibration reference; acquiring historical deviation information of the target position; determining a change rate of structural dynamic characteristics according to the historical deviation information; calculating a first weight of the deviation amount and a second weight of the historical deviation information according to the change rate of the structural dynamic characteristics, the first weight being positively correlated with the change rate of the structural dynamic characteristics; performing weighted summation on the deviation amount and the historical deviation information according to the first weight and the second weight to obtain an adjustment amount required by the associated kinematic feature; updating the associated kinematic feature according to the adjustment amount.

[0014] In another aspect, an embodiment of the present application provides a hierarchical cutting machining parameter control system, comprising: a workpiece hierarchical module configured to hierarchize a heat-sensitive workpiece to obtain an upper machining layer and a lower machining layer, the lower machining layer having a lower heat dissipation capacity than the upper machining layer; a region division module configured to divide a to-be-machined region of the lower machining layer into a plurality of discrete machining units; a sequence generation module, configured to generate a processing sequence, wherein the processing sequence is an order for cutting the plurality of discrete processing units, and the discrete processing units corresponding to two adjacent cutting operations in the processing sequence are not spatially adjacent; A cutting control module is used to control cutting processing parameters of the plurality of discrete processing units according to the processing sequence.

[0015] The embodiments of the present application include at least the following beneficial effects: the embodiments of the present application first layer the heat-sensitive workpiece to obtain an upper processing layer and a lower processing layer, then divide the area to be processed of the lower processing layer into multiple discrete processing units, and then generate a processing sequence for characterizing the order of cutting the multiple discrete processing units, and the discrete processing units corresponding to two adjacent cutting operations in the processing sequence are not adjacent in space. Finally, according to the processing sequence, the cutting processing parameters of the multiple discrete processing units are controlled, so that layered cutting processing parameter control can be achieved in combination with different processing sequences, thereby improving product quality and reliability.

[0016] Other features and advantages of the present invention will be described in the following description, and in part will become apparent from the description, or will be understood by practicing the present invention. The purpose and other advantages of the present invention can be realized and obtained through the structures particularly pointed out in the description and the drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0018] Figure 1 This is a flow chart of a layered cutting processing parameter control method according to an embodiment of the present invention; Figure 2 This is a structural diagram of a layered cutting processing parameter control system according to an embodiment of the present invention. DETAILED DESCRIPTION

[0019] In order to make the objectives, technical solutions, and advantages of this application more clearly understood, the present application is further described in detail below in conjunction with the accompanying drawings and examples. It should be understood that the specific embodiments described herein are only intended to illustrate this application and are not intended to limit this application. When the following description refers to the drawings, unless otherwise indicated, the same numbers in different drawings represent the same or similar elements.

[0020] It can be understood that the terms "first", "second" and the like used in the present application can be used herein to describe various concepts, but unless specifically stated, these concepts are not limited by these terms. These terms are only used to distinguish one concept from another concept. For example, without departing from the scope of the embodiments of the present application, the first information can also be referred to as the second information, and similarly, the second information can also be referred to as the first information. Depending on the context, the word "if" as used herein can be interpreted as "when" or "upon" or "in response to determining".

[0021] The terms "at least one", "multiple", "each", "any" and the like used in the present application include one, two or more than two, multiple includes two or more than two, each refers to each of the corresponding plurality, and any refers to any one of the plurality.

[0022] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as understood by a person skilled in the art to which the present application belongs. The terms used herein are only for the purpose of describing the embodiments of the present application, and are not intended to limit the present application.

[0023] Before the embodiments of the present application are described in detail, first, some nouns and terms involved in the embodiments of the present application are explained, and the nouns and terms involved in the embodiments of the present application are applicable to the following explanations.

[0024] Cutting: refers to a mechanical machining method that uses a tool with a regular shape to cut off excess material from the surface of a workpiece, so as to ensure that the geometry, size accuracy, surface roughness and surface layer quality meet the design requirements. The workpiece can be a blank or a semi-finished product; its material can be metal or non-metal; the tool used can be single-edged or multi-edged. Cutting is a basic machining method in manufacturing industry and is widely used in production.

[0025] In the related art, the traditional existing layered cutting processing, especially when processing heat-sensitive workpieces with complex deep cavity structure, when the processing from shallow layer to deep layer, the processing environment will change dramatically, especially the deterioration of cooling and chip removal conditions, which may have unexpected negative effects on the microstructure and mechanical properties of the workpiece material. The performance defects introduced between the layers due to inconsistent conditions between the two processes are a hidden and unpredictable quality problem, which is directly related to the service life and reliability of the final product, and the product quality is low, and the reliability is low. The core technical problem is how to plan the cutting path of the subsequent processing layer to actively control the spatial distribution and time accumulation of cutting heat on the interlayer bonding interface, so as to avoid the overtempering of the surface hardened layer formed by the previous processing layer due to local heat accumulation, and finally prevent the formation of performance degradation micro-soft band at the interlayer bonding.

[0026] For example, suppose in a constant temperature processing workshop for manufacturing precision injection mold, a high-precision five-axis machining center is processing a mold core forged from H13 hot work die steel. The final form of the mold core requires a long and narrow cavity with a depth of 200 mm and a width of 30 mm. The mechanical properties of H13 steel after quenching and tempering are sensitive to the thermal history of the machining process. The machining scheme is divided into two layered milling steps, each with a depth of 100 mm. In the first step, i.e. machining the cavity to a depth of 0 to 100 mm, the external cooling system can effectively pour emulsified coolant into the cutting area, efficiently removing cutting heat and flushing away chips. After the machining is completed, a layer of work-hardened layer is formed on the surface of the cavity, and the microstructure is stable. However, when the machine tool performs the second layer cutting of 100 to 200 mm depth, due to the deep and narrow shape of the cavity, the external cooling liquid cannot effectively reach the cutting area. The cooling method is forced to switch to the micro-lubrication system sprayed by the spindle. Although the micro-lubrication system ensures lubrication and chip removal, its ability to remove overall heat is significantly different from that of large-flow liquid cooling. After the second layer processing is completed, when performing continuous hardness scanning on the inner wall of the mold cavity, a hardness drop is recorded at exactly 100 mm depth. Metallographic analysis shows that in the low hardness zone, the tempered martensite structure of H13 steel shows signs of coarsening, and the carbide particles also have a tendency to aggregate and grow, which is consistent with the overtempered microstructure. This indicates that when the second layer is processed, the high temperature generated by the tool preheats the work-hardened layer left by the first layer processing through heat conduction, causing the material in this layer to overtemper, resulting in a decrease in hardness and strength. This phenomenon forms a micro-soft band at the interlayer bonding of the mold cavity side wall, affecting the service life of the mold.

[0027] If the above problems are not solved, in the layered cutting process of heat-sensitive workpieces, especially when the cooling conditions between the layers change, the improper spatial distribution and time accumulation of cutting heat on the interlayer bonding interface will cause the overtempering of the formed surface hardened layer. This overtempering phenomenon will cause a local decrease in material hardness and strength, forming a micro-soft band. This soft band will become a weak link in the structure during the service of the final product, and will not be able to resist external stress, wear or fatigue load, thereby significantly shortening the service life and reliability of the product. For precision molds, this means that the mold may fail prematurely during production, leading to production interruptions, increased scrap rates, and high repair or replacement costs. For other critical components, this hidden performance defect can cause catastrophic failures under extreme conditions, posing a threat to equipment safety and operational stability. Therefore, solving the problem of cutting heat accumulation at the interlayer bonding is crucial to ensuring the machining quality and service performance of heat-sensitive workpieces.

[0028] In the face of the above problems, the first thought of the present application is to reduce the generation of cutting heat by reducing the cutting parameters, such as reducing the cutting speed or feed rate. However, this method will significantly reduce the machining efficiency, and in deep cavity machining, even if the overall heat is reduced, the problem of local heat accumulation still exists, making it difficult to effectively avoid overtempering at the interlayer bonding. In this regard, further thinking is to try to improve the cooling method, such as developing more efficient deep cavity cooling technology. However, due to the geometric structure of the deep cavity and the extension length of the tool, traditional high-flow cooling fluid is difficult to effectively reach the cutting area, while the micro-lubrication system can provide lubrication but has limitations in removing overall heat. Therefore, simply relying on the improvement of the cooling method is difficult to fundamentally solve the problem. In view of the above challenges, the present application shifts the solution to the fine control of the cutting machining path and parameters. Considering that heat conduction and dissipation in the material takes time, if continuous cutting on the same area or adjacent area can be avoided, enough time will be provided for heat dissipation. Based on this, the present application conceives a method of dividing the machining area into multiple discrete units and generating a special machining sequence. The characteristic of this sequence is that the discrete machining units corresponding to two adjacent cutting operations are not adjacent in space. This means that after cutting on one unit, the immediately adjacent unit is skipped and other areas are machined, so that the previously machined area has time to dissipate heat. Subsequently, according to this machining sequence, the cutting parameters of each discrete machining unit are controlled to further optimize heat input and distribution. This strategy aims to actively manage the spatial distribution and time accumulation of cutting heat from the level of machining path and parameter control, thereby effectively avoiding local heat accumulation and preventing overtempering at the interlayer bonding.

[0029] The embodiments of the present application will be specifically explained in combination with the drawings: Figure 1 is an optional flowchart of a layered cutting process parameter control method provided by an embodiment of the present application, Figure 1 The method in the above embodiment can include, but is not limited to, steps S101-S104.

[0030] Step S101, layering the heat-sensitive workpiece to obtain an upper machining layer and a lower machining layer, the heat dissipation capability of the lower machining layer being lower than that of the upper machining layer; Step S102, dividing the to-be-machined region of the lower machining layer into a plurality of discrete machining units; Step S103, generating a machining sequence, the machining sequence being the sequence of machining the plurality of discrete machining units, the discrete machining units corresponding to two adjacent machining operations in the machining sequence being spatially non-adjacent; Step S104, controlling the machining process parameters of the plurality of discrete machining units according to the machining sequence.

[0031] The steps S101-S104 shown in the above embodiment can realize layered cutting process parameter control in combination with different machining sequences, thereby improving product quality and reliability.

[0032] In some embodiments, steps S101-S104 can first layer the heat-sensitive workpiece to obtain an upper machining layer and a lower machining layer, wherein the heat dissipation capability of the lower machining layer is lower than that of the upper machining layer. Then the to-be-machined region of the lower machining layer is divided into a plurality of discrete machining units, which enables fine management of the machining region. Then a machining sequence is generated, wherein the machining sequence is the sequence of machining the plurality of discrete machining units, the discrete machining units corresponding to two adjacent machining operations in the machining sequence being spatially non-adjacent. This enables the adjacent region of a discrete machining unit to not be machined immediately after the machining of the discrete machining unit, thereby providing the region with heat dissipation and cooling time. This time interval avoids the accumulation of cutting heat in the local region, reducing the local temperature peak. Finally, the machining process parameters of the plurality of discrete machining units are controlled according to the machining sequence, for example, the cutting speed, feed rate or cutting depth are adjusted to further manage the heat input of each unit. Through this heat management strategy combining spatial dispersion and time interval, the present embodiment can control the distribution and accumulation of cutting heat on the interlayer bonding interface, thereby preventing the material over tempering phenomenon caused by local heat concentration and avoiding the formation of performance-degrading micro-soft bands at the key bonding sites.

[0033] It can be understood that the discrete machining unit refers to the decomposition of a continuous machining area into smaller, independently processable areas, which can be achieved by techniques such as grid partitioning, point cloud sampling, or feature area segmentation, etc. The main purpose is to realize the fine management and control of the machining area, and facilitate subsequent independent parameter adjustment and heat management for each small area. The discrete machining units corresponding to two adjacent cutting operations in the machining sequence are not adjacent in space, which means that the execution order of the cutting operation is designed to be jump-like, i.e. the current cutting unit and the next cutting unit are not directly adjacent in physical position. It can be generated by using jump-like milling path, chessboard format machining sequence or interval machining strategy, etc. The main purpose is to avoid the rapid accumulation of cutting heat in the local area, allowing the machined area to have enough cooling and heat dissipation time, thereby reducing the local temperature peak and preventing the material from deteriorating due to overheating.

[0034] In order to more clearly illustrate the technical scheme, specific examples are used for explanation. Taking the machining of a heat-sensitive H13 die steel workpiece with a deep and narrow cavity as an example, first, the cavity depth of the workpiece is layered, for example, the lower half of the cavity is defined as the lower machining layer, which is difficult for the cooling liquid to reach due to geometric constraints, and the heat dissipation capacity is lower than the upper half. Then, the machining area of the lower machining layer, such as the specific depth area of the cavity bottom or side wall, is divided into multiple discrete machining units, which can be achieved by decomposing the continuous machining path into a series of independent, small-size machining blocks in the numerical control programming software. Subsequently, a machining sequence is generated, which ensures that when the discrete machining units are cut, the discrete machining units corresponding to two adjacent cutting operations are not adjacent in space. For example, a jump-like or interval machining strategy can be used, first machining area A, then skipping adjacent areas B and C, machining area D, and then returning to machining area B or C after area A has enough time to dissipate heat. Finally, the cutting machining parameters of each discrete machining unit are controlled according to the generated machining sequence. This can include introducing a short non-cutting waiting time before moving to the next non-adjacent unit after cutting a unit, or dynamically adjusting the cutting feed rate and cutting depth to ensure that the heat input on each discrete machining unit is managed, thereby avoiding excessive accumulation of local heat.

[0035] By the technical solution, the embodiment can solve the problem of material performance degradation at the interlayer bonding caused by the difference in heat dissipation capacity of the upper and lower processing layers in the layered cutting processing of the heat-sensitive workpiece. By dividing the lower processing area into discrete units and using spatially non-adjacent cutting sequences, the cutting heat is dispersed inside the workpiece, avoiding the accumulation of heat in the local area. This strategy provides the processed area with heat dissipation time, thereby reducing the local temperature peak and inhibiting the risk of overtempering of the surface hardened layer formed by the first layer processing. The embodiment ensures the stability of the material organization and mechanical properties at the interlayer bonding, prevents the formation of microscopic soft bands, and improves the overall quality and service reliability of the workpiece.

[0036] In some embodiments, in step S104, the cutting processing parameter control on the plurality of discrete processing units according to the processing sequence can include but is not limited to the following steps: setting an energy injection limit according to the processing sequence; collecting the power consumption value of the spindle drive motor at preset collection time intervals; controlling the energy accumulation value of the single cutting operation of the discrete processing unit to be less than the energy injection limit, the energy accumulation value being calculated according to the power consumption value.

[0037] In some embodiments, the time interval between adjacent cutting operations is usually a fixed value, and for workpieces with different properties, using a fixed time interval may not be able to well control the heat production. Therefore, the interval between adjacent cutting operations can be further determined by detecting the injected energy. The energy injection limit can be set according to the processing sequence, which fully considers the characteristics of the heat-sensitive workpiece in the lower processing layer with poor heat dissipation capacity, as well as the specific position of the discrete processing unit in the processing sequence and its surrounding heat dissipation environment, providing a clear upper limit for subsequent energy control. Then, the power consumption value of the spindle drive motor is collected at preset collection time intervals, and the real-time monitoring mechanism can accurately reflect the actual heat generated during cutting, providing data for the calculation of the energy accumulation value, and the data is reliable. Then, the energy accumulation value of the single cutting operation of the discrete processing unit is controlled to be less than the energy injection limit, wherein the energy accumulation value is calculated according to the power consumption value, and the system can dynamically adjust the cutting parameters to ensure that the energy input of each cutting operation is within a safe range.

[0038] It can be understood that the energy injection limit refers to the maximum energy allowed to be input during the single cutting operation of the discrete processing unit, which can be a pre-set fixed value or a value calculated according to the heat sensitivity and heat dissipation capacity of the workpiece material, as well as the position of the current processing unit in the processing sequence and the surrounding environmental conditions, the purpose of which is to limit the generation of cutting heat from the source and prevent overtempering or organization degradation in the local area of the workpiece due to excessive energy input.

[0039] To make the technical solution clearer, specific examples are used for explanation below. Before cutting the lower layer, according to the thermal conductivity, specific heat capacity of the workpiece material and the geometric parameters of the tool, an energy injection limit can be calculated and set for each discrete machining unit at a specific position in the machining sequence through a pre-established empirical database or thermodynamic model. For example, the energy injection limit of the area with poor heat dissipation conditions at the bottom of the deep cavity can be set relatively low. During cutting, the instantaneous power consumption value of the spindle drive motor can be collected in real time at a preset collection time interval of, for example, every 50 milliseconds, using a power sensor integrated in the numerical control system of the machine tool or a separate electric energy metering module. These power consumption values are continuously transmitted to the machine tool controller or a separate energy management unit. When a single cutting operation of a discrete machining unit starts, the energy management unit continuously accumulates the power consumption values obtained from the spindle drive motor, and calculates the energy cumulative value of the cutting operation by integrating the instantaneous power values within the cutting duration. During cutting, the energy management unit compares the currently calculated energy cumulative value with the pre-set energy injection limit in real time. If the energy cumulative value approaches or reaches the energy injection limit, the machine tool controller can immediately trigger the adjustment of the cutting parameters, for example, automatically reducing the feed speed or spindle speed, to reduce the energy input per unit time, so as to ensure that the energy cumulative value of the single cutting operation always remains below the energy injection limit, avoiding excessive local heat concentration.

[0040] Through the above technical solution, the embodiment can realize accurate management of energy input during cutting. By pre-setting the energy injection limit and monitoring and controlling the energy cumulative value of the single cutting operation of the discrete machining unit in real time, the generation and accumulation of cutting heat can be limited, thereby avoiding local overheating of the workpiece during machining. This is valuable for deep cavity machining of heat-sensitive materials, can prevent material organization deterioration or over tempering due to heat concentration, ensures stable material performance in the machining area, and further improves machining quality and workpiece reliability.

[0041] In some embodiments, in step S104, the cutting machining parameter control of the plurality of discrete machining units according to the machining sequence can include but is not limited to the following steps: Step S201, according to the machining sequence, controlling the single cutting time of the discrete machining unit to be less than or equal to a first preset time threshold; Step S202, according to the machining sequence, controlling the time interval between adjacent cutting operations of the discrete machining unit to be greater than or equal to a second preset time threshold.

[0042] In some embodiments, since simply performing continuous cutting can not be able to sufficiently avoid local heat concentration, heat can accumulate on the interlayer bonding interface, causing the surface hardening layer formed by the first layer of machining to be over tempered. In order to more finely control the heat input during the cutting process, avoid local overheating. According to the machining sequence, the single cutting time of the discrete machining unit can be controlled to be less than or equal to a first preset time threshold. This means that for each independent cutting area, the duration of the cutting operation is strictly limited, thereby directly limiting the total amount of heat generated during a single cutting process, avoiding the sharp rise in local temperature due to long-time continuous cutting. Then according to the machining sequence, the time interval between adjacent cutting operations of the discrete machining unit is greater than or equal to a second preset time threshold. This means that when a discrete machining unit is cut to completion, a sufficiently long waiting time is introduced before the next cutting of the spatially adjacent discrete machining unit. This time interval provides sufficient conduction and dissipation opportunities for the heat generated by the previous cutting operation, allowing the heat to diffuse from the cutting area to the surrounding base material, avoiding the continuous accumulation of heat in adjacent areas.

[0043] To make the technical solution clearer, specific examples are used for explanation. In the layered cutting of the lower processing layer of the heat-sensitive workpiece, the region to be processed is first divided into multiple discrete processing units. Then, a processing sequence is generated, which ensures that spatially adjacent discrete processing units are not continuously cut. Specifically, to control the heat input during cutting, a first preset time threshold can be set in advance, for example, determined through experiments or simulations, when the single cutting time exceeds this threshold, the local temperature of the workpiece may reach the critical point of over tempering. In actual processing, the numerical control system is configured to monitor the single cutting duration of each discrete processing unit in real time. Once it is detected that the single cutting time of a certain discrete processing unit is about to reach or has reached the first preset time threshold, the system can automatically adjust the cutting parameters, such as reducing the feed speed or spindle speed, or pausing the current cutting operation, to ensure that the single cutting time does not exceed the threshold. In addition, to ensure that the heat has enough time to dissipate, a second preset time threshold can be set. This threshold can be determined according to the thermal diffusion coefficient of the material, the cooling conditions, and the allowable temperature drop rate. In the processing sequence, after the cutting operation of a discrete processing unit is completed, before switching to the next discrete processing unit that is not spatially adjacent but may be cut in the subsequent sequence, the system checks whether the current time interval meets the second preset time threshold. If the actual time interval is insufficient, the system can generate a non-cutting machine tool motion path, such as making the tool run empty outside the workpiece, or performing a short empty walk on the non-critical area of the workpiece, to fill the time until the second preset time threshold is met. In this way, before cutting the next discrete processing unit, the heat in the previous cutting area has been sufficiently dissipated, thereby avoiding the accumulation of heat at the interlayer junction.

[0044] Through the above technical solution, the heat input during the layered cutting of the heat-sensitive workpiece can be finely managed. By limiting the single cutting time, excessive heat can be effectively avoided in a single cutting area within a short period of time; by extending the time interval between adjacent cutting operations, sufficient diffusion and dissipation time is provided for the generated heat, thereby avoiding excessive accumulation of heat in the local area. Thus, the problem of over tempering at the interlayer junction due to deteriorating heat dissipation conditions during deep processing of heat-sensitive workpieces can be effectively solved, thereby maintaining the microstructure and mechanical properties of the workpiece and improving the reliability of the product.

[0045] In some embodiments, in step S202, according to the processing sequence, the time interval between adjacent cutting operations of the discrete processing units is greater than or equal to the second preset time threshold, which can include but is not limited to the following steps: Step S301, according to the processing sequence, calculate the total duration of cutting other processing units in the time interval; Step S302, if the total time length is less than the second preset time threshold, calculating a time difference according to the total time length and the second preset time threshold; Step S303, generating a non-cutting machine tool motion path according to the time difference, the execution time length of the non-cutting machine tool motion path being equal to the time difference; Step S304, executing the non-cutting machine tool motion path.

[0046] In some embodiments, it can be insufficient to guarantee sufficient heat dissipation effect by merely making the machine tool in a stationary state within the time interval, because the heat exchange efficiency between the workpiece or the tool and the environment is low in the stationary state, and the idle time cannot be effectively utilized for active heat dissipation, resulting in local heat accumulation. Therefore, the time interval between adjacent cutting operations can be utilized to dissipate heat from the workpiece while also dissipating heat from the tool, so as to achieve better heat dissipation effect.

[0047] The total time length of cutting other machining units in the time interval can be calculated according to the machining sequence, so as to reveal how much time is actually occupied by the cutting task within the preset time interval, and thus the potential idle time can be identified. If the total time length is less than the second preset time threshold, it can be identified that there is an idle time that is not fully utilized. A time difference is calculated according to the total time length and the second preset time threshold, and the time difference represents the additional idle time that can be actively utilized. Then, a non-cutting machine tool motion path is generated according to the time difference, and the non-cutting machine tool motion path is executed, wherein the execution time length of the non-cutting machine tool motion path is equal to the time difference. This means that the machine tool no longer simply waits in a stationary state before the next cutting operation starts, but performs a purposeful motion. By executing the non-cutting machine tool motion path, the motion of the machine tool can drive the surrounding air to flow, or change the relative position of the workpiece or the tool and the cooling medium, thereby enhancing the convective heat exchange efficiency of the workpiece surface and accelerating the dissipation of heat from the inside of the workpiece to the external environment.

[0048] It can be understood that the non-cutting machine tool motion path refers to a preset trajectory followed by the moving parts (such as the spindle, the worktable or the tool) of the machine tool without material cutting, which can be a linear motion, a curved motion or a composite motion, and the purpose is to utilize the motion of the machine tool to enhance the heat exchange between the workpiece or the tool and the surrounding environment, thereby promoting heat dissipation.

[0049] To make the technical solution clearer, specific examples are used for explanation below. Assume that when deep cavity layered cutting is performed on a heat-sensitive mold steel workpiece, the machining control system has planned the cutting sequence of discrete machining units according to the machining sequence, and set the second preset time threshold that the time interval between adjacent cutting operations should be greater than or equal to 5 seconds. After the cutting of a discrete machining unit is completed, the system will immediately check the start time of the next cutting operation in the machining sequence, and calculate whether there are other non-adjacent discrete machining units that need to be cut within the 5-second time interval. If the system calculates that only 2 seconds are used for cutting other machining units within the 5-second time interval, there are 3 seconds of idle time (5 seconds minus 2 seconds). At this time, the control system will automatically generate a non-cutting machine tool movement path according to the 3-second time difference. This path can be a simple Z-axis lifting and lowering movement, or a small range of reciprocating movement in the X-Y plane within the safety area, and the movement speed and acceleration will be optimized to ensure that the execution time is exactly 3 seconds. Once the non-cutting machine tool movement path is generated, the machine tool will immediately execute the path. For example, the machine tool spindle can be lifted from the current machining position to a safe height, and then moved along a preset path, such as a small circular or square trajectory movement above the workpiece, and then returned to the starting position of the next cutting operation. In this way, the machine tool continuously maintains the movement state within the 3 seconds of waiting for the start of the next cutting operation, thereby promoting the air flow of the workpiece surface, accelerating heat dissipation, and effectively reducing the local temperature of the workpiece, creating a better thermal environment for subsequent cutting operations.

[0050] Through the above technical solution, the embodiment can more effectively utilize the time interval between adjacent cutting operations, and convert the otherwise wasted idle time into active heat dissipation time. By executing a non-cutting machine tool movement path during the idle time, heat exchange between the workpiece and the surrounding environment can be enhanced, and heat dissipation can be accelerated, thereby effectively reducing the local temperature rise of the heat-sensitive workpiece during machining, avoiding material property degradation caused by heat accumulation, such as overtempering, and ultimately improving machining quality and workpiece reliability.

[0051] In some embodiments, in step S303, generating a non-cutting machine tool movement path according to the time difference can include but is not limited to the following steps: Step S401, constructing kinematic feature constraints of the non-cutting machine tool movement path, the kinematic feature constraints being used to suppress structural vibration caused by machine tool movement; Step S402, generating the geometry and speed curve of the non-cutting machine tool movement path according to the time difference and the kinematic feature constraints; Step S403, generating the non-cutting machine tool movement path according to the geometry and speed curve.

[0052] In some embodiments, considering only time factor can cause the machine tool to generate structural vibration when performing non-cutting motion, affecting the machining precision and efficiency. In order to suppress the structural vibration caused by the machine tool motion, the kinematic characteristic constraint of the non-cutting machine tool motion path can be constructed first, wherein the kinematic characteristic constraint is used to suppress the structural vibration caused by the machine tool motion, for example, by limiting the parameters such as speed, acceleration or jerk, to ensure that the machine tool remains stable during the motion. Then, according to the time difference and the kinematic characteristic constraint, the geometry and speed curve of the non-cutting machine tool motion path are generated, which means that the generated path not only meets the time compensation requirement, but also meets the vibration suppression requirement in the shape of the trajectory and the change of the speed, thereby avoiding the vibration caused by simply pursuing time compensation. According to the geometry and speed curve, the non-cutting machine tool motion path is generated, so that the machine tool can effectively utilize the time difference to meet the time interval requirement of the adjacent cutting operation during the non-cutting motion, and can also reduce or eliminate the structural vibration through fine kinematic control.

[0053] It can be understood that the kinematic characteristic constraint refers to the limiting condition of the kinematic parameters such as position, speed, acceleration and jerk of the machine tool during the non-cutting motion, which can be specifically set by setting the maximum allowable speed, the maximum allowable acceleration and the like, or by limiting the curvature change rate of the motion trajectory, and the purpose is to avoid resonance or excessive vibration of the machine tool during high-speed or sharp turning motion, thereby protecting the machine tool structure and improving the machining stability.

[0054] To make the technical solution clearer, specific examples are used for explanation below. In generating the non-cutting machine tool motion path, the natural frequencies and vibration response characteristics of the machine tool in different motion states can be obtained first by modal analysis or vibration testing on a specific machine tool model, so as to construct the kinematic characteristic constraints. For example, the maximum allowable jerk value of each axis of the machine tool can be set to avoid exciting the low-order resonance modes of the machine tool structure. Subsequently, when it is necessary to generate a non-cutting path according to a time difference, for example, if the calculated time difference is 2 seconds and the machine tool needs to move from the current position to the starting position of the next machining unit, the system will consider both the 2-second time limit and the preset kinematic characteristic constraints. The path planning algorithm can use a method based on a spline curve (such as a B-spline or NURBS curve) to generate a smooth geometric shape, and at the same time, the speed planning module will generate a corresponding speed curve according to the time difference and the kinematic constraints (such as maximum speed, maximum acceleration) to ensure that the motion is completed within the specified time and no vibration is generated. For example, if the time difference allows, the system can choose a longer path with smaller curvature changes and run at a lower, smooth speed to further reduce the risk of vibration. Finally, the generated geometric shape and speed curve are converted into G code or motion instructions that can be recognized by the machine tool controller, for example, through a series of G01 (linear interpolation) and G02 / G03 (circular interpolation) instructions with F (feed speed) parameters, so as to drive the machine tool to perform non-cutting motion according to the planned path and speed.

[0055] Through the above technical solution, when generating a non-cutting machine tool motion path according to a time difference, the structural vibration caused by machine tool motion can be suppressed. This makes the machine tool run stably when performing non-cutting motion, avoiding impact and resonance, thereby improving the stability and precision of the machining process. At the same time, since the vibration is controlled, the wear of machine tool parts is reduced, prolonging the service life of the equipment and improving the production efficiency and product quality.

[0056] In some embodiments, in step S402, generating the geometric shape and speed curve of the non-cutting machine tool motion path according to the time difference and the kinematic characteristic constraints can include but is not limited to the following steps: Obtaining geometric information of the heat-sensitive workpiece in the machining space; Generating boundary conditions according to the geometric information, the boundary conditions being used to constrain the geometric shape of the non-cutting machine tool motion path; Generating the geometric shape and speed curve of the non-cutting machine tool motion path according to the time difference, the kinematic characteristic constraints and the boundary conditions.

[0057] In some embodiments, since the non-cutting machine tool movement path is generated only according to the time difference and the kinematic feature constraints, the generated path can not meet the actual machining requirements, for example, it can collide with the heat-sensitive workpiece, or the generated path is not smooth, causing the machine tool to vibrate. In order to more accurately generate the geometry and speed curve, the geometric information of the heat-sensitive workpiece in the machining space can be obtained first. These geometric information is the basis for ensuring the safety of the machine tool movement path, because the heat-sensitive workpiece is particularly sensitive to collision and improper contact during machining. Then, according to the geometric information, boundary conditions are generated, which are used to constrain the geometry of the non-cutting machine tool movement path. These boundary conditions can accurately define the areas that the machine tool must avoid during non-cutting movement, such as the surface, internal structure or machined area of the workpiece, thereby effectively constraining the geometry of the non-cutting machine tool movement path and preventing the machine tool from interfering or colliding with the workpiece. Then, according to the time difference, the kinematic feature constraints and the boundary conditions, the geometry and speed curve of the non-cutting machine tool movement path are generated. In addition to considering the preset time difference and kinematic feature constraints, these newly generated boundary conditions are also taken into account. By comprehensively considering the time difference, the kinematic feature constraints and the boundary conditions, the path planning algorithm can generate a non-cutting movement path that meets the time requirements, is smooth in motion, and completely avoids the workpiece.

[0058] It can be understood that the boundary condition refers to the restriction or requirement imposed on the geometry of the non-cutting machine tool movement path, which can specifically refer to the starting point, the termination point, the intermediate passing point, the avoidance area, the safety distance or the specific shape constraint of the path, and its purpose is to ensure that the generated path meets the safety and process requirements.

[0059] To make the technical solution clearer, specific examples are used for explanation below. In generating the geometry and velocity profile of the non-cutting machine tool movement path, first, the three-dimensional model data of the workpiece to be processed can be imported from a computer-aided design (CAD) system to obtain accurate geometric information. These geometric information can include the surface mesh, solid model or point cloud data of the workpiece. Then, based on these geometric information, the path planning software can automatically identify and generate a series of boundary conditions. For example, the surface of the workpiece can be set as an impassable obstacle, and a minimum safety distance can be defined to ensure that the machine tool cutter or spindle always maintains this safety distance from the workpiece during non-cutting movement. These boundary conditions can be represented as a series of spatial region restrictions, such as forbidden areas, allowed areas or specific path points. Subsequently, the path planning module can use optimization algorithms, such as methods based on spline curve interpolation or B-spline curve fitting, combined with pre-set time differences, kinematic constraints of the machine tool (such as maximum speed, maximum acceleration, jerk limit, and movement patterns that avoid resonance frequencies), and the boundary conditions generated earlier, to calculate and generate an optimal geometry and velocity profile of the non-cutting machine tool movement path. For example, if the time difference requires the machine tool to complete the movement within 2 seconds, the kinematic constraints require the maximum speed not to exceed 10 meters / second and the jerk to be smooth, and the boundary conditions require to avoid a specific groove of the workpiece, the algorithm will find a path that completes the movement within 2 seconds, with smooth speed and no collision with the groove. The geometry of the path can be a composite curve, and the velocity curve can be an S-shaped curve to ensure the smoothness of the movement.

[0060] Through the above technical solution, when generating the non-cutting machine tool movement path, the actual geometry of the heat-sensitive workpiece can be fully considered to avoid collision between the machine tool and the workpiece during non-cutting movement, improving the safety of processing. At the same time, combined with the kinematic constraints and the time difference, the generated path meets the time requirements of the processing rhythm and ensures the smoothness of the machine tool movement, suppresses the structural vibration caused by the machine tool movement, and improves the processing precision and the surface quality of the workpiece.

[0061] In some embodiments, in step S401, constructing the kinematic constraints of the non-cutting machine tool movement path can include but is not limited to the following steps: Step S501, obtaining first position information within the machine tool workspace and second position information of the non-cutting machine tool movement path; Step S502, constructing a target correspondence relationship between the first position information and a target kinematic constraint, the target kinematic constraint being used to suppress structural vibration; Step S503, constructing the kinematic constraints according to the second position information and the target correspondence relationship.

[0062] In some embodiments, due to the lack of consideration of the dynamic characteristics of the machine tool at different workspace positions in the process of constructing the kinematic feature constraints, the non-cutting motion path may cause or exacerbate structural vibration at certain specific positions, and the structural vibration caused by the machine tool motion cannot be effectively suppressed, thereby affecting the machining precision and stability. To more effectively suppress structural vibration, first position information within the machine tool workspace and second position information of the non-cutting machine tool motion path can be obtained, thereby providing a spatial positioning basis for subsequent vibration suppression strategies. Then a target correspondence between the first position information and the target kinematic feature is constructed, the target kinematic feature being used to suppress structural vibration, and the establishment of the target correspondence enables the machine tool to dynamically select or adjust the kinematic parameters when performing non-cutting motion according to the specific position it is in, thereby actively avoiding or mitigating resonance or structural vibration caused by motion. Then, according to the second position information and the target correspondence, the kinematic feature constraints are constructed to ensure that the planning of the non-cutting motion path not only meets the time difference requirement, but also optimizes the kinematic characteristics to suppress vibration.

[0063] To make the technical solution clearer, specific examples are used for explanation below. First, a series of representative discrete points can be pre-selected as first position information within the machine tool workspace. These points can be uniformly distributed throughout the workspace, or concentrated in areas where the machine tool structure dynamic characteristics change significantly. For each first position information point, the vibration response data of the machine tool when performing a specific motion at that position can be obtained through experimental testing or simulation analysis, and the target kinematic characteristics that can effectively suppress vibration are determined accordingly, such as the maximum allowable speed, acceleration of each axis of the machine tool at that position, or the recommended trajectory smoothness parameters. These data can be stored in a database or lookup table, thereby constructing the target correspondence between the first position information and the target kinematic characteristics. When generating a non-cutting machine tool motion path is needed, a series of key points or sampling points on the path can be obtained as second position information first. These second position information points can represent the start, end and turning points in the middle of the path. For each second position information point, the target kinematic characteristics corresponding to the position can be obtained by querying the target correspondence established earlier. For example, if the second position information point is located in a known area of the machine tool workspace where resonance is prone to occur, the target correspondence can indicate that lower speed and acceleration limits should be adopted in this area, and higher trajectory smoothness is required. Finally, according to these second position information points and their corresponding target kinematic characteristics, the kinematic characteristic constraints of the non-cutting machine tool motion path can be constructed. These constraints will be input into the path planning algorithm to guide the algorithm to generate the geometry and speed curve of the non-cutting motion path that meets the time difference requirement and at the same time suppresses the structure vibration. For example, the path planner will ensure that the local speed and acceleration of the generated path when passing through a specific second position information point do not exceed the limit values obtained from the target correspondence, and the curvature change rate of the path meets the smoothness requirement, thereby avoiding exciting the inherent vibration mode of the machine tool.

[0064] Through the above technical solution, the embodiment can dynamically construct the kinematic characteristic constraints of the non-cutting machine tool motion path according to the dynamic characteristics of the machine tool at different workspace positions. This makes the planning of the non-cutting path no longer a simple geometric connection, but incorporates the consideration of vibration suppression, thereby effectively suppressing the structural vibration caused by machine tool motion. This helps to improve the running stability of the machine tool during non-cutting process, reduce the adverse effects of vibration on machining precision, and thus improve the machining quality and surface integrity of the final workpiece.

[0065] In some embodiments, in step S502, constructing the target correspondence between the first position information and the target kinematic characteristics can include but is not limited to the following steps: Step S601, constructing an initial correspondence between the first position information and the target kinematic characteristics; Step S602, actual vibration information of the machine tool when performing the motion path at the target position is obtained, and the first position information includes the target position; Step S603, according to the target position and the initial correspondence relationship, the associated kinematic characteristics are determined; Step S604, according to the associated kinematic characteristics, the vibration reference is determined; Step S605, if the actual vibration information exceeds the vibration reference, the associated kinematic characteristics are updated; Step S606, according to the updated associated kinematic characteristics, the initial correspondence relationship is updated to obtain the target correspondence relationship.

[0066] In some embodiments, since the structural dynamic characteristics of the machine tool change over time and with the change of the use environment, the pre-set target correspondence relationship is no longer optimal, which affects the vibration suppression effect. Therefore, the target correspondence relationship between the first position information and the target kinematic characteristics can be dynamically updated according to the actual vibration of the machine tool to adapt to the change of the structural dynamic characteristics of the machine tool.

[0067] The initial correspondence relationship between the first position information and the target kinematic characteristics can be constructed first, and the actual vibration information of the machine tool when performing the motion path at the target position is obtained, wherein the first position information includes the target position. Then, according to the target position and the initial correspondence relationship, the associated kinematic characteristics are determined, which are key parameters affecting the vibration level. Then, according to the associated kinematic characteristics, the vibration reference is determined as a basis for judging whether the actual vibration is within an acceptable range. If the actual vibration information exceeds the vibration reference, it indicates that the current kinematic characteristic parameters can no longer effectively suppress vibration, and the associated kinematic characteristics can be updated. This update is based on actual vibration feedback, so that the kinematic characteristics can adapt to the change of the structural dynamic characteristics of the machine tool. Finally, according to the updated associated kinematic characteristics, the initial correspondence relationship is updated to obtain the target correspondence relationship. This dynamic updating mechanism ensures that the kinematic characteristic constraints of the machine tool can be continuously optimized to effectively suppress structural vibration under different working conditions and long-term operation. Even when the machine tool performs non-cutting motion for heat management, high precision and stability can be maintained, and new machining defects caused by vibration can be avoided, thereby improving the overall machining quality and efficiency, especially for deep cavity machining of heat-sensitive workpieces, which can effectively avoid the performance degradation problem at the interlayer bonding site.

[0068] It can be understood that the actual vibration information refers to the data reflecting the vibration state of the structure of the machine tool in real time collected by the sensor when the machine tool executes a specific motion path, which can include vibration acceleration, vibration speed, vibration displacement and other physical quantities, which are obtained through sensors such as accelerometers, laser vibration meters or strain gauges, and the purpose is to objectively evaluate the vibration level of the machine tool under the current kinematic characteristic parameters as the basis for judging whether adjustment is needed. The vibration reference refers to a preset threshold or standard for measuring whether the actual vibration level of the machine tool is acceptable, which can be set according to the design specification of the machine tool, the processing process requirement, the industry standard or the statistical analysis result of historical operation data, which can be a fixed value or a dynamically changing range, and the purpose is to provide an objective basis for determining when to trigger the update of the associated kinematic characteristics.

[0069] In order to more clearly illustrate the technical scheme, specific examples are used for explanation below. The initial correspondence between the first position information and the target kinematic characteristics can be established by a database established by finite element analysis or modal analysis in advance, or by a series of test runs under typical working conditions, recording the vibration response under different positions and motion parameters, and then obtaining the mapping model through regression analysis or neural network training. In the actual operation process of the machine tool, the actual vibration information of the machine tool when executing the motion path at the target position can be obtained, which can be collected in real time by installing three-axis accelerometers on the machine tool spindle box, workbench or key bearing seat. These accelerometers convert the vibration signal into an electrical signal and transmit it to the controller through a data acquisition card. The first position information includes the target position, such as the path point or interpolation point defined in the numerical control program of the machine tool. According to the current target position and the initial correspondence, the system can determine the associated kinematic characteristics, such as the feed speed, axis acceleration and the like corresponding to the current target position. Subsequently, according to these associated kinematic characteristics, the vibration reference can be determined, such as setting the machine tool vibration level specified in the ISO 2372 standard, or according to historical processing experience, the surface roughness requirement of a specific workpiece is inversely calculated as the maximum allowed vibration acceleration peak value. If the actual vibration information, such as the root mean square value of the vibration acceleration, exceeds the vibration reference, an adaptive control algorithm, such as a method based on gradient descent or reinforcement learning, can be used to fine-tune the associated kinematic characteristics corresponding to the current target position. For example, if the vibration is too large, the allowed maximum acceleration or jerk at that position can be appropriately reduced. Finally, according to the updated associated kinematic characteristics, the initial correspondence can be updated to obtain a target correspondence. This can be by modifying the corresponding entries in the lookup table, or by updating the coefficients of the parameterized model through online learning algorithms such as Kalman filtering or recursive least squares, so that the new target correspondence can reflect the current real dynamic characteristics of the machine tool.

[0070] By the technical solution, the embodiment can dynamically update the target correspondence between the first position information and the target kinematic feature. By acquiring the actual vibration information of the machine tool in real time and comparing it with the vibration benchmark, the system can timely discover and respond to the change of the machine tool structure dynamic characteristics. When the vibration exceeds the acceptable range, the scheme can automatically adjust the associated kinematic feature and update the target correspondence accordingly, so that the vibration suppression strategy of the machine tool always remains in the optimal or near-optimal state. This effectively solves the problem of decline in vibration suppression effect caused by long-term operation, wear and tear or environmental changes of the machine tool, ensures that the machine tool can maintain high precision and stability throughout its life cycle, and thus improves the processing quality, reduces the scrap rate, and may prolong the service life of the key components of the machine tool.

[0071] In some embodiments, in step S605, updating the associated kinematic feature can include but is not limited to the following steps: calculating the deviation amount according to the actual vibration information and the vibration benchmark; acquiring historical deviation information of the target position; determining a change rate of the structure dynamic characteristics according to the historical deviation information; calculating a first weight of the deviation amount and a second weight of the historical deviation information according to the change rate of the structure dynamic characteristics, the first weight being positively correlated with the change rate of the structure dynamic characteristics; weighting and summing the deviation amount and the historical deviation information according to the first weight and the second weight to obtain an adjustment amount required by the associated kinematic feature; updating the associated kinematic feature according to the adjustment amount.

[0072] In some embodiments, since only the historical deviation information and the current actual vibration information are fused according to a fixed proportion, the change of the structure dynamic characteristics is not considered, which may lead to insufficient accuracy of the adjustment when the vibration characteristics of the machine tool change, and the structure vibration cannot be effectively suppressed.

[0073] To improve the accuracy of adjustment, the deviation amount can be calculated according to the actual vibration information and the vibration reference, so as to quantify the current vibration state. Then, the historical deviation information of the target position is obtained, which contains the vibration data of the position in the past period of time and can reflect the dynamic characteristics of the machine tool structure. According to the historical deviation information, the change rate of the structure dynamic characteristics is determined, which reflects the trend of the inherent characteristics such as machine tool stiffness, damping and the like changing with time. Then, the first weight of the deviation amount and the second weight of the historical deviation information are calculated according to the change rate of the structure dynamic characteristics, wherein the first weight is positively correlated with the change rate of the structure dynamic characteristics. This means that when the machine tool structure characteristics change rapidly, the system will pay more attention to the current actual vibration information to quickly respond to the new vibration state; on the contrary, when the structure characteristics are relatively stable, the system will refer more to the historical deviation information to maintain the stability and robustness of the adjustment. According to the first weight and the second weight, the deviation amount and the historical deviation information are weighted and summed to obtain the adjustment amount required for the associated kinematic characteristics, which comprehensively reflects the current vibration deviation and the historical vibration trend and can more accurately reflect the actual vibration demand of the machine tool. Finally, the associated kinematic characteristics are updated according to the adjustment amount, thereby improving the accuracy of the adjustment of the associated kinematic characteristics.

[0074] It can be understood that the deviation amount refers to the difference between the current machine tool actual vibration state and the preset or expected vibration reference, which can be represented by the difference or ratio of vibration amplitude, frequency or energy and the like, and the purpose is to quantify the deviation of the current vibration from the ideal state. The historical deviation information refers to the vibration data recorded by the target position in the past period of time, which can contain a series of time sequence vibration amplitudes, frequencies, phases or statistical characteristics such as mean, variance or trend, and the purpose is to reflect the vibration trend and stability of the machine tool structure in a period of time. The change rate of the structure dynamic characteristics refers to the speed of the inherent properties of the machine tool structure in vibration response changing with time, which can be determined according to the trend analysis of the vibration parameters in the historical deviation information, the drift of the spectral characteristics or the identification results of the modal parameters, and the purpose is to evaluate whether the characteristics such as machine tool stiffness, damping or mass distribution are changing significantly. The adjustment amount refers to the specific numerical value or vector used to correct the associated kinematic characteristics, which can be a comprehensive correction value obtained by weighting and summing the deviation amount and the historical deviation information, and the purpose is to provide an accurate correction instruction to optimize the kinematic characteristics of the machine tool.

[0075] To make the technical solution clearer, specific examples are used for explanation below. First, the actual vibration information of the machine tool when performing the motion path at the target position can be collected in real time by using the acceleration sensor installed at the key position of the machine tool, for example, the root mean square value of the vibration signal is obtained. At the same time, the system will preset a vibration reference, which can be the vibration root mean square threshold value obtained by a large number of experimental data statistics in the stable running state of the machine tool. Then, by comparing the actual vibration information collected in real time with the vibration reference, the current deviation is calculated, for example, the difference between the two is calculated. Next, the system will obtain the historical deviation information accumulated in the past period of time of the target position from the storage unit, which can be a deviation sequence containing multiple time points. In order to determine the change rate of the structural dynamic characteristics, the system can perform trend analysis on the historical deviation information, for example, by using linear regression algorithm to calculate the slope of the deviation with respect to time, or by calculating the average change rate between adjacent deviations. If the calculated slope or average change rate is large, it indicates that the change rate of the structural dynamic characteristics is high. Based on this change rate, the system can dynamically calculate the first weight of the deviation and the second weight of the historical deviation information. For example, a change rate threshold can be set, when the change rate of the structural dynamic characteristics exceeds this threshold, the first weight can be set to a relatively high value, for example 0.7, and the second weight is set to 0.3 accordingly; on the contrary, when the change rate is lower than the threshold, the first weight can be set to 0.3, and the second weight is set to 0.7. This ensures that the first weight is positively correlated with the change rate of the structural dynamic characteristics. Subsequently, the system calculates the first weight and the second weight, and then the current deviation and a representative value (for example, the average value or the latest value of the historical deviation information) in the historical deviation information are weighted and summed, so as to obtain the adjustment amount required for the associated kinematic characteristics. For example, the adjustment amount can be equal to the first weight multiplied by the deviation, plus the second weight multiplied by the average value of the historical deviation information. Finally, the system superimposes this adjustment amount on the current associated kinematic characteristics, and completes the update of the associated kinematic characteristics, for example, if the associated kinematic characteristics is a speed or acceleration limit parameter used to suppress vibration, then the new limit parameter will be the old parameter plus or minus the adjustment amount.

[0076] By the technical solution, when the associated kinematic characteristics are updated, the current actual vibration information and the historical deviation information can be dynamically fused. By adjusting the weight of the deviation and the historical deviation information according to the change rate of the structure dynamic characteristics, the adjustment of the associated kinematic characteristics is more accurate and adaptive. When the structure characteristics change rapidly, the system can quickly respond to the current vibration state; when the structure characteristics are stable, the historical data can be used to maintain the stability of the adjustment. This effectively solves the problem of how to accurately adjust the associated kinematic characteristics, thereby more effectively suppressing the structure vibration of the machine tool and improving the stability of the machine tool movement and the machining precision.

[0077] The beneficial effects of implementing the embodiments of the present application include that the embodiments of the present application first layer the heat-sensitive workpiece to obtain an upper machining layer and a lower machining layer, then divide a to-be-machined region of the lower machining layer into a plurality of discrete machining units, generate a machining sequence for representing a sequence of cutting the plurality of discrete machining units, and the discrete machining units corresponding to two adjacent cutting operations in the machining sequence are not adjacent in space, and finally control cutting machining parameters of the plurality of discrete machining units according to the machining sequence, so that layered cutting machining parameter control can be realized in combination with different machining sequences, thereby improving product quality and reliability.

[0078] As shown in Figure 2 The embodiments of the present application also provide a layered cutting machining parameter control system, which comprises: A workpiece layering module 701 is configured to layer a heat-sensitive workpiece to obtain an upper machining layer and a lower machining layer, and the heat dissipation capacity of the lower machining layer is lower than that of the upper machining layer; A region dividing module 702 is configured to divide a to-be-machined region of the lower machining layer into a plurality of discrete machining units; A sequence generating module 703 is configured to generate a machining sequence, the machining sequence being a sequence of cutting the plurality of discrete machining units, and the discrete machining units corresponding to two adjacent cutting operations in the machining sequence are not adjacent in space; A cutting control module 704 is configured to control cutting machining parameters of the plurality of discrete machining units according to the machining sequence.

[0079] The contents in the above method embodiments are all applicable to the system embodiments, the system embodiments specifically implement the same functions as the above method embodiments, and achieve the same beneficial effects as the above method embodiments.

[0080] Those skilled in the art can understand that the technical solutions shown in the drawings do not constitute a limitation on the embodiments of the present application, and can include more or fewer steps than the drawings, or combine certain steps or different steps.

[0081] The embodiments described in the embodiments of the present application are used to more clearly illustrate the technical solutions of the embodiments of the present application, and do not constitute a limitation on the technical solutions provided by the embodiments of the present application. Those skilled in the art can know that, with the evolution of technology and the appearance of new application scenarios, the technical solutions provided by the embodiments of the present application are also applicable to similar technical problems.

Claims

1. A layered cutting parameter control method, characterized in that: The following steps are involved: The heat-sensitive workpiece is layered to obtain an upper processing layer and a lower processing layer, wherein the heat dissipation capacity of the lower processing layer is lower than that of the upper processing layer; Dividing the to-be-processed area of ​​the lower processing layer into a plurality of discrete processing units; generating a processing sequence, wherein the processing sequence is an order for cutting the plurality of discrete processing units, wherein the discrete processing units corresponding to two adjacent cutting operations in the processing sequence are not spatially adjacent; According to the processing sequence, cutting processing parameters of the plurality of discrete processing units are controlled.

2. The method according to claim 1, characterized in that The controlling of cutting parameters of the plurality of discrete machining units according to the machining sequence includes: setting an energy injection limit according to the processing sequence; The power consumption value of the spindle drive motor is collected at preset collection time intervals; An energy accumulation value of a single cutting operation of the discrete machining unit is controlled to be less than the energy injection limit, and the energy accumulation value is calculated according to the power consumption value.

3. The method according to claim 1, characterized in that The controlling of cutting parameters of the plurality of discrete machining units according to the machining sequence includes: According to the processing sequence, controlling the single cutting time of the discrete processing unit to be less than or equal to a first preset time threshold; According to the processing sequence, the time interval between adjacent cutting operations of the discrete processing units is controlled to be greater than or equal to a second preset time threshold.

4. The method according to claim 3, characterized in that The step of controlling the time interval between adjacent cutting operations of the discrete machining units to be greater than or equal to a second preset time threshold according to the machining sequence includes: According to the processing sequence, calculating the total duration of cutting of other processing units in the time interval; If the total duration is less than the second preset time threshold, calculating the time difference according to the total duration and the second preset time threshold; generating a non-cutting machine tool motion path according to the time difference, wherein the execution time of the non-cutting machine tool motion path is equal to the time difference; The non-cutting machine motion path is executed.

5. The method according to claim 4, characterized in that Generating a non-cutting machine tool motion path according to the time difference includes: Constructing kinematic feature constraints for the non-cutting machine tool motion path, wherein the kinematic feature constraints are used to suppress structural vibration caused by the machine tool motion; generating a geometry and a velocity curve of the non-cutting machine tool motion path according to the time difference and the kinematic characteristic constraint; The non-cutting machine tool motion path is generated according to the geometric shape and speed curve.

6. The method according to claim 5, characterized in that Generating the geometry and speed curve of the non-cutting machine tool motion path according to the time difference and the kinematic characteristic constraint includes: Acquiring geometric information of the heat-sensitive workpiece in a processing space; generating boundary conditions based on the geometric information, wherein the boundary conditions are used to constrain the geometry of the non-cutting machine tool motion path; The geometry and speed curve of the non-cutting machine tool motion path are generated according to the time difference, the kinematic characteristic constraint and the boundary condition.

7. The method according to claim 5, characterized in that The kinematic feature constraints of constructing the non-cutting machine tool motion path include: Acquiring first position information within a machine tool workspace and second position information of the non-cutting machine tool motion path; establishing a target correspondence relationship between the first position information and a target kinematic feature, wherein the target kinematic feature is used to suppress structural vibration; The kinematic feature constraint is constructed according to the second position information and the target correspondence.

8. The method according to claim 7, characterized in that The establishing of a target correspondence relationship between the first position information and the target kinematic characteristics includes: Establishing an initial correspondence between the first position information and the target kinematic characteristics; Acquiring actual vibration information of the machine tool when executing the motion path at a target position, wherein the first position information includes the target position; determining associated kinematic features according to the target position and the initial corresponding relationship; determining a vibration reference based on the associated kinematic characteristics; If the actual vibration information exceeds the vibration reference, updating the associated kinematic feature; The initial correspondence is updated according to the updated associated kinematic features to obtain the target correspondence.

9. The method according to claim 8, characterized in that The updating of the associated kinematic features includes: Calculating a deviation amount according to the actual vibration information and the vibration reference; Obtaining historical deviation information of the target position; determining a rate of change of a structural dynamic characteristic based on the historical deviation information; calculating a first weight of the deviation and a second weight of the historical deviation information according to a rate of change of the structural dynamic characteristics, wherein the first weight is positively correlated with the rate of change of the structural dynamic characteristics; performing a weighted summation of the deviation amount and the historical deviation information according to the first weight and the second weight to obtain an adjustment amount required for the associated kinematic feature; The associated kinematic feature is updated according to the adjustment amount.

10. A layered cutting parameter control system, characterized in that: include: A workpiece layering module is used to layer the heat-sensitive workpiece to obtain an upper processing layer and a lower processing layer, wherein the heat dissipation capacity of the lower processing layer is lower than that of the upper processing layer; An area division module, used for dividing the to-be-processed area of ​​the lower processing layer into a plurality of discrete processing units; a sequence generation module, configured to generate a processing sequence, wherein the processing sequence is an order for cutting the plurality of discrete processing units, and the discrete processing units corresponding to two adjacent cutting operations in the processing sequence are not spatially adjacent; A cutting control module is used to control cutting processing parameters of the plurality of discrete processing units according to the processing sequence.

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