A thin-walled structure milling chatter suppression method and device based on spindle speed parameter adaptive regulation, electronic equipment and storage medium

Abstract

The application provides a kind of thin-walled structure milling chatter suppression method and device based on spindle speed parameter adaptive control, electronic equipment, storage medium, according to stability lobe diagram, determine continuous variable speed dominant area and discrete variable speed dominant area, form complete variable speed milling chatter suppression method: if in low speed area, use sine continuous variable speed modulation, optimize modulation parameters based on energy minimization criterion and generate continuous variable speed curve;If in high speed area, calculate stable target speed according to phase difference matching condition, and generate discrete speed sequence through low-pass filtering and saturation constraint processing;When stability improvement amplitude is lower than threshold value, the speed is divided into discrete variable speed dominant area, and discrete variable speed strategy is used.The application does not need additional vibration suppression device or hardware modification, has the advantages of simple implementation and low cost, and has significant effect in improving machining stability and efficiency.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of thin-walled workpiece milling, in particular to a thin-walled structure milling chatter suppression method and device based on spindle speed parameter adaptive regulation, electronic equipment and storage medium. BACKGROUND

[0002] In the process of thin-walled workpiece milling, due to low workpiece stiffness and large cutting force fluctuation, machining chatter is easily induced. Chatter will reduce the quality of the machined surface, exacerbate tool wear, and affect machining efficiency and part accuracy. Traditional chatter suppression methods mainly include passive and active control. Passive methods, such as damping tools, dampers or increasing workpiece support, can suppress chatter to some extent, but often require additional hardware devices, increasing processing costs and affecting processing accessibility. Active control methods based on piezoelectric actuators or electromagnetic actuators have better control effect, but the system is more complex, the cost is high, and the compatibility requirement of numerical control machine tool is higher, which is difficult to popularize and apply on ordinary machine tools. The spindle speed regulation-based chatter suppression method has attracted widespread attention due to its need for no additional hardware and easy implementation. The spindle speed regulation method mainly includes continuous variable speed cutting and discrete variable speed strategy, which can effectively improve the stability boundary and eliminate or suppress the occurrence of chatter. The continuous variable speed method disperses cutting energy through continuous frequency modulation, which has obvious suppression effect in the low speed area, but in the high speed area, the modulation frequency may couple with the system natural frequency and exacerbate the chatter; the discrete variable speed method avoids the critical speed by discrete jumping, which has better stability in the high speed area, but in the low speed area, the suppression may fail due to insufficient jump amplitude. Existing methods usually use a single fixed modulation strategy and do not consider the difference in modulation strategy in different speed intervals, which cannot adapt to the whole speed range. Moreover, the two strategies cannot be directly combined together. If the two strategies are simply combined, parameter conflicts (such as mismatching of modulation frequency and jump step) may occur, resulting in control failure. In addition, the modulation parameters (such as modulation amplitude and modulation frequency in continuous speed) are usually determined by trial and error or experience. When the dynamic characteristics change during processing, constant modulation parameters cannot guarantee the suppression effect. These reasons make it difficult to effectively suppress the occurrence of chatter in thin-walled workpiece milling. SUMMARY

[0003] The purpose of the present application is to provide a thin-walled structure milling chatter suppression method and device based on spindle speed parameter adaptive regulation, electronic equipment and storage medium. Only the spindle speed instruction needs to be adjusted by the numerical control system, without additional vibration suppression devices or hardware modification. The method has the advantages of easy implementation and low cost, and is suitable for various milling processing scenes, which has a significant effect on improving processing stability and efficiency.

[0004] To achieve the above technical purposes, the technical solutions adopted by the present application are as follows:

[0005] In a first aspect, the application discloses a thin-walled structure milling chatter suppression method based on spindle speed parameter adaptive control, which comprises the following steps:

[0006] S1, constructing a stability blade diagram based on the dynamic characteristics of the thin-walled workpiece during milling, determining the critical threshold by calculating the critical stable value under the maximum modulation parameter allowed at continuous variable speed and comparing it with the critical value at the conventional speed;

[0007] S2, judging the preset spindle speed region according to the critical threshold, dividing it into a continuous variable speed dominant region and a discrete variable speed dominant region, selecting the corresponding speed control strategy according to the judged speed region, adjusting the spindle speed in real time and monitoring the processing state; if the speed is in the continuous variable speed dominant region, the sinusoidal continuous variable speed modulation is adopted, the speed modulation parameters include amplitude ratio and frequency ratio, a series of modulation parameters arranged from small to large in energy is generated by using the RV factor representing energy, and the modulation parameter with the minimum energy is selected as the first choice to generate a smooth continuous variable speed curve; if it is in the discrete variable speed dominant region, the stable target speed is calculated according to the phase difference matching condition, and the discrete speed sequence is generated through low-pass filtering and saturation constraint processing, and the discrete speed with the minimum difference value from the preset spindle speed is selected as the target speed;

[0008] S3, monitoring the chatter on line according to the multi-source signal characteristics, if the chatter is suppressed, maintaining the current spindle speed and outputting the stable processing state until the processing is completed, if the chatter is not suppressed, switching to step S2 and switching to the next group of parameter combination for continuous control; for the continuous variable speed dominant region, the next group of speed modulation parameters is selected according to the order from small to large in energy, and for the discrete variable speed dominant region, the corresponding discrete speed is selected as the target speed according to the order from small to large in the difference value between the discrete speed and the preset spindle speed. For example, for the continuous variable speed dominant region, the speed modulation parameter corresponding to the first RV factor is selected in the previous group, and the speed modulation parameter corresponding to the second RV factor is selected in the next group, and so on; for the discrete variable speed dominant region, the discrete speed with the minimum difference value is selected in the previous group, and the discrete speed with the second minimum difference value is selected in the next group, and so on.

[0009] Further, the continuous variable speed dominant region adopts sinusoidal continuous variable speed modulation, and the process of optimizing the speed modulation parameter and generating a smooth speed curve based on the energy minimization criterion comprises the following steps:

[0010] The speed of the sinusoidal continuous variable speed modulation is represented as:

[0011] ;

[0012] Wherein, ,​ , Ω0 represents the amplitude of the nominal speed, Ω1 represents the amplitude of the speed variation, ω m represents the angular frequency of the speed variation, , f m represents the main flutter frequency when flutter occurs under the condition that the speed is in the continuous variable speed dominant zone; f0 represents the frequency of the nominal speed; RVA and RVF represent the amplitude ratio and the frequency ratio, respectively, and t represents the time t;

[0013] The speed modulation parameters are calculated based on the energy minimum principle and are represented as follows:

[0014] ;

[0015] wherein, ;

[0016] In the formula, k0 represents the number of lobes of the stability lobe diagram; represents the phase difference between the current tool tooth and the previous tool tooth vibration displacement in milling; N t represents the number of cutter teeth; ω c represents the flutter angular frequency when flutter occurs; m f represents the modulation degree, which is obtained by calculating the local minimum value of the 0-order first kind Bessel function;

[0017] The results calculated according to the above formula include a series of modulation parameters. In order to perform parameter optimization and reduce the energy consumption of the machine tool, the RV factor representing the energy is introduced to sort the speed modulation parameters according to the energy size. The RV factor is represented as follows:

[0018] ;

[0019] According to the parameter priority, the speed modulation parameter combination with the smallest RV factor is selected to generate a continuous and smooth sinusoidal variable speed curve as the continuous variable speed curve.

[0020] Further, the discrete variable speed dominant zone calculates the stable target speed according to the phase difference matching condition, and generates the discrete speed sequence through low-pass filtering and saturation constraint processing. The process includes the following steps:

[0021] The target speed for stable machining is calculated according to the phase difference matching condition, so that the phases of the modulation waves of adjacent two cutting are the same. The target speed is represented as follows:

[0022] ;

[0023] In the formula, k is the number of complete flutter waves contained between two consecutive cutting, is the main flutter frequency when flutter occurs under the condition that the speed is in the discrete variable speed dominant zone, which is calculated according to the vibration signal in machining;

[0024] The rotational speed is constrained and processed by a low-pass filter and a saturation module to generate a discrete rotational speed sequence.

[0025] Further, in step S3, the processing vibration signal is continuously collected, and whether the chatter is effectively suppressed is determined by analyzing the chatter characteristic frequency components contained therein.

[0026] In a second aspect, the application discloses a thin-walled structure milling chatter suppression device based on spindle speed parameter adaptive regulation, the device comprises:

[0027] A rotational speed threshold setting module is configured to construct a stability blade diagram based on the dynamic characteristics during workpiece milling, determine the critical threshold by calculating the critical stability value under the maximum modulation parameter allowed at the continuous variable rotational speed, and comparing the critical value at the conventional rotational speed;

[0028] A rotational speed division module is configured to determine the rotational speed region to which the preset spindle speed belongs according to the critical threshold;

[0029] A rotational speed regulation module is configured to select the corresponding rotational speed regulation strategy according to the determined rotational speed region, adjust the spindle speed in real time and monitor the processing state; if the rotational speed is in the continuous variable rotational speed dominant region, a sinusoidal continuous variable rotational speed modulation is adopted, the rotational speed modulation parameters include amplitude ratio and frequency ratio, a series of modulation parameters arranged in ascending order of energy are generated by using the RV factor representing energy, and the modulation parameter with the minimum energy is selected as the first selection to generate a smooth continuous variable rotational speed curve; if the rotational speed is in the discrete variable rotational speed dominant region, the stable target rotational speed is calculated according to the phase difference matching condition, and a discrete rotational speed sequence is generated by low-pass filtering and saturation constraint processing, and the discrete rotational speed with the minimum difference value from the preset spindle speed is selected as the target rotational speed;

[0030] A chatter monitoring module is configured to monitor the chatter online according to the multi-source signal characteristics, keep the current spindle speed and output the stable processing state if the chatter is suppressed until the processing is completed, and switch to the next group of parameter combinations to continue the regulation if the chatter is not suppressed; for the continuous variable rotational speed dominant region, the next group of rotational speed modulation parameters are selected in ascending order of energy, and for the discrete variable rotational speed dominant region, the corresponding discrete rotational speed is selected as the target rotational speed in ascending order of the difference value between the discrete rotational speed and the preset spindle speed.

[0031] In a third aspect, the application discloses an electronic device, which comprises one or more processors, a storage device configured to store one or more programs, and when the one or more programs are executed by the one or more processors, the one or more processors implement the thin-walled structure milling chatter suppression method based on spindle speed parameter adaptive regulation as described above.

[0032] In a fourth aspect, the application discloses a computer readable storage medium, which stores a computer program, and the program is executed by a processor to realize the thin-walled structural part milling chatter suppression method based on spindle speed parameter adaptive regulation.

[0033] Compared with the prior art, the application has the following beneficial effects:

[0034] Firstly, the thin-walled structural part milling chatter suppression method and device based on spindle speed parameter adaptive regulation, the electronic equipment and the storage medium effectively combine continuous variable speed cutting and discrete variable speed modulation strategies, so that the optimal strategy can be adopted for adjustment in different speed intervals, and parameter conflicts are avoided, greatly reducing the trial and error cost and improving the chatter suppression efficiency.

[0035] Secondly, in the machining process, the thin-walled structural part milling chatter suppression method and device based on spindle speed parameter adaptive regulation, the electronic equipment and the storage medium only need to adjust the spindle speed instruction of the numerical control system, without additional hardware, thereby reducing the use cost and ensuring the real-time and stability of the chatter suppression.

[0036] Thirdly, the thin-walled structural part milling chatter suppression method and device based on spindle speed parameter adaptive regulation, the electronic equipment and the storage medium are suitable for various milling machining scenes, and have a significant chatter suppression effect on high chatter risk working conditions such as thin-walled parts and difficult-to-machine materials. BRIEF DESCRIPTION OF DRAWINGS

[0037] Figure 1 A flowchart of a thin-walled structural part milling chatter suppression method based on spindle speed parameter adaptive regulation is provided for the embodiments of the application.

[0038] Figure 2 A speed regulation region division schematic diagram in a stability blade diagram is provided for the embodiments of the application.

[0039] Figure 3 A curve schematic diagram of a low-speed region sinusoidal continuous variable speed modulation method is provided for the embodiments of the application.

[0040] Figure 4a A stability blade diagram of constant speed milling and continuous variable speed milling is constructed based on the dynamic characteristics of the thin-walled workpiece.

[0041] Figure 4b A speed critical threshold division schematic diagram based on stability improvement amount is provided for the embodiments of the application.

[0042] Figure 5 A continuous variable speed milling stability blade curve diagram is provided for the embodiments of the application.

[0043] Figure 6aand Figure 6b The vibration displacement graphs before and after the speed regulation of the continuous variable speed dominant zone provided for the embodiments of the present application; wherein, Figure 6a Corresponding to the constant speed milling condition (before speed regulation), Figure 6b Corresponding to the sinusoidal continuous variable speed condition (after speed regulation);

[0044] Figure 7 The vibration displacement graphs before and after the speed regulation of the discrete variable speed dominant zone provided for the embodiments of the present application. DETAILED DESCRIPTION

[0045] The embodiments of the present application are further described in detail below with reference to the accompanying drawings.

[0046] In an embodiment, as shown in Figure 1 , the present application provides a thin-walled structure milling chatter suppression method based on spindle speed parameter adaptive regulation, comprising:

[0047] First, according to the stability lobe diagram of the milling machining system, the spindle speed is divided into continuous variable speed dominant zone and discrete variable speed dominant zone, and the critical threshold of region division is determined (as shown in Figure 2 ), when the spindle speed is less than , it is in the continuous variable speed dominant zone; when the spindle speed is greater than less than , it is in the discrete variable speed dominant zone, indicates the limit speed of the machine tool.

[0048] Second, before processing, according to the preset spindle speed, it is judged whether it belongs to the continuous variable speed dominant zone or the discrete variable speed dominant zone, so as to automatically select the corresponding regulation strategy.

[0049] Third, select the speed regulation strategy by zone.

[0050] As shown in Figure 3 , the speed of the continuous variable speed dominant zone when using sinusoidal continuous variable speed modulation is:

[0051] ;

[0052] Wherein, , .

[0053] Wherein, , , Ω0 represents the amplitude of the nominal speed, Ω1 represents the change amplitude of the speed, ω m represents the angular frequency of the speed change, , f mf0is the frequency of the nominal speed; RVAand RVFare the amplitude ratio and frequency ratio, respectively; , f0is the frequency of the nominal speed; RVAand RVFare the amplitude ratio and frequency ratio, respectively;

[0054] The speed modulation parameters are calculated based on the energy minimum principle, which is expressed as:

[0055] ;

[0056] wherein, .

[0057] In the formula, k0represents the number of lobes of the stability lobe diagram; φrepresents the phase difference between the vibration displacement of the current cutter tooth and the previous cutter tooth in milling processing; N t N represents the number of cutter teeth; ω c f0is the frequency of the nominal speed; RVAand RVFare the amplitude ratio and frequency ratio, respectively; f m represents the modulation degree, which is obtained by calculating the local minimum value of the 0-order first Bessel function; f = 3.83, 10.17, 16.47, 22.76,…

[0058] Then the RV factor is introduced to prioritize the speed modulation parameters, and the RV factor is expressed as:

[0059] ;

[0060] According to the parameter priority, the combination of the speed modulation parameters with the smallest RV factor is selected to generate a continuous and smooth sinusoidal variable speed curve.

[0061] The discrete variable speed method is used in the discrete variable speed dominant zone. The target speed for stable processing is calculated according to the phase difference matching condition. The vibration displacement between the current cutter tooth and the previous cutter tooth in milling processing produces a phase difference, which leads to the occurrence of chatter, and the phase difference is expressed as:

[0062] ;

[0063] In the formula, and represent the real part and the imaginary part of , respectively; G(ω) represents the transfer function of the processing system.

[0064] When the real part of the transfer function of the processing system in the phase difference calculation formula is , the stable cutting width reaches the maximum, and at this time Therefore, the phase of the modulation wave of the two adjacent cutting should be the same to avoid the occurrence of chatter.

[0065] When the phase of the modulation wave of the two adjacent cutting is the same, i.e. the target rotating speed is expressed as:

[0066] ;

[0067] In the formula, k is the number of complete chatter waves contained between two consecutive cutting, k = 0, 1, 2, 3…; is the main chatter frequency when the rotating speed is in the discrete variable speed dominant region, which is calculated according to the vibration signal in the machining;

[0068] The rotating speed is constrained by a low-pass filter and a saturation module to generate a discrete rotating speed sequence, thereby avoiding the impact of sudden changes in rotating speed on the stability of machining.

[0069] Fourthly, real-time adjustment of rotating speed and monitoring of machining state. In the machining process, the vibration signal is collected in real time, the chatter frequency characteristics are analyzed, and it is judged whether the chatter is effectively suppressed. If the chatter is not suppressed, the next set of parameter combination is automatically switched to continue to control; if the chatter is suppressed, the current parameters are maintained and the stable machining instruction is output.

[0070] To illustrate the process of chatter suppression in thin-walled structure milling based on adaptive control of spindle rotating speed parameters, thin-walled workpiece milling is taken as an example for simulation analysis. First, the critical threshold of region division is determined, a 4-fluted flat-bottom milling cutter with a diameter of 12 mm is used as the machining tool, and the stability lobe diagram of constant speed milling and continuous variable speed milling is constructed based on the dynamic characteristics of thin-walled workpiece (as shown in Figure 4a Fig. 1), and the spindle speed range is set to 2000-10000 rpm and the axial depth of cut range is set to 0-10 mm. Figure 4bThe stability improvement amount is used as the evaluation index for comparative analysis. Considering the uncertainty factors such as calculation error in the process of solving stability, the threshold value is set to -5%, which means that when the stability improvement effect of continuous variable speed milling is lower than this value, its stability is worse than that of constant speed milling. Under the condition of considering the actual machine tool dynamic performance constraint, the maximum modulation parameters RVA and RVF are set to 0.3. It can be seen that when the spindle speed exceeds 5300 rpm, the stability range of variable speed milling appears obvious reduction, and the stability improvement amount is lower than the set threshold value, which confirms the limitation of continuous variable speed strategy in high speed range. Based on this, 5300 rpm is set as the switching boundary of the speed control strategy, which provides a theoretical basis for the development of subsequent partition control strategy. The nominal speed of 3000 rpm is selected for simulation verification, which is below the switching boundary of 5300 rpm, so the sinusoidal continuous variable speed strategy is adopted for chatter suppression. The modulation parameters are determined by the RV factor. After calculation, the modulation parameters under the minimum RV factor are: RVA=0.071, RVF=0.036, and the reconstructed continuous variable speed milling stability lobe based on these parameters is shown in Figure 5 Point A (3000 rpm) has been transferred from the original unstable region to below the critical stability curve corresponding to variable speed milling, indicating the stability improvement effect of sinusoidal continuous variable speed strategy in low speed range. To further verify the universality of the control strategy, point C is selected for comparative analysis, where the speed of point C has exceeded the switching boundary of the control strategy and needs to use discrete variable speed method for control. The vibration displacement before and after speed modulation for the machining condition of point A (3000 rpm) is shown in Figure 6a and Figure 6b f tp is the tooth passing frequency, which represents the multiple of the spindle speed frequency, and when only the tooth passing frequency appears in the frequency spectrum, it indicates that the machining is stable. As shown in Figure 6a , under the condition of constant speed milling, the vibration displacement amplitude is about 0.08 mm, and the significant chatter frequency component appears in the frequency spectrum, indicating that the system is in an unstable state. As shown in Figure 6b , when the sinusoidal continuous variable speed control strategy is introduced, the system dynamic response is improved, and the vibration displacement amplitude is reduced to 0.05 mm, and the frequency spectrum only contains the spindle rotation frequency and its multiple, indicating that the chatter is effectively suppressed. It is worth noting that due to the introduction of periodic disturbance by speed modulation, the vibration displacement presents regular fluctuation synchronized with the modulation frequency. Although this controlled fluctuation increases the range of instantaneous amplitude change, it will not cause system instability through frequency spectrum analysis, and it belongs to controllable stable vibration mode. When the speed is 6800 rpm, i.e. point B in Figure 5 , the discrete variable speed strategy is used for calculation, and the result is shown in Figure 7As shown. Without speed control, the vibration displacement exhibits a divergent trend over time, with a maximum amplitude of 0.48 mm. The frequency spectrum is dominated by chatter frequency components, and analysis revealed that the main chatter frequency is 514 Hz, indicating instability in the machining system. Subsequently, based on the chatter frequency calculation, a discrete variable speed strategy was implemented. Figure 5 The nearest target speed at point B is 7710 rpm, which is... Figure 5 Point C in the middle. From Figure 7 As can be seen, after the rotational speed is switched to 7710 rpm, the vibration displacement converges rapidly, with the maximum amplitude being only 0.001 mm, and there is no chatter frequency in the spectrum, indicating that the machining process is stable, proving the effectiveness of the discrete variable speed strategy in the high speed range.

[0071] This invention provides a method for suppressing chatter during milling of thin-walled structural parts based on adaptive control of spindle speed parameters. The method divides the speed range according to a stability lobe diagram, determining a continuously variable speed dominant region and a discrete variable speed dominant region, forming a complete chatter suppression method for variable speed milling. In the low-speed region, sinusoidal continuous speed modulation is used, and modulation parameters are optimized based on the energy minimization criterion to generate a smooth speed curve. In the high-speed region, a stable target speed is calculated based on phase difference matching conditions, and a discrete speed sequence is generated through low-pass filtering and saturation constraint processing. To quickly determine the division boundary, the critical stability value under the maximum allowable modulation parameters under continuously variable speed is calculated and compared with the critical value under conventional speed. When the stability improvement is less than a threshold, the speed is classified into the discrete variable speed dominant region, and a discrete variable speed strategy is adopted. This invention uses the optimal strategy for different speed ranges, reducing trial-and-error costs and improving vibration suppression efficiency. During implementation, only the spindle speed command of the CNC system needs to be adjusted, requiring no additional hardware, reducing operating costs, and ensuring the real-time performance and stability of chatter suppression. This invention is applicable to various milling processing scenarios, and has a significant vibration suppression effect, especially for high chatter risk conditions such as thin-walled parts and difficult-to-machine materials.

[0072] Although preferred embodiments of this application have been described, those skilled in the art, upon learning the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments as well as all changes and modifications falling within the scope of this application.

[0073] Obviously, those skilled in the art can make various modifications and variations to this application without departing from the spirit and scope of this application. Therefore, if such modifications and variations fall within the scope of the claims of this application and their equivalents, this application also intends to include such modifications and variations.

Claims

1. A method for suppressing chatter during milling of thin-walled structural parts based on adaptive control of spindle speed parameters, characterized in that, The method includes the following steps: S1. Based on the dynamic characteristics of thin-walled workpiece milling, a stability lobe diagram is constructed. The critical stability value under the maximum allowable modulation parameter under continuous variable speed is calculated and compared with the critical value under conventional speed to determine the critical threshold. S2, based on the critical threshold, determine the speed range of the preset spindle speed, dividing it into a continuous variable speed dominant range and a discrete variable speed dominant range. Select the corresponding speed control strategy based on the determined speed range to adjust the spindle speed in real time and monitor the machining status. If the speed is in the continuous variable speed dominant range, sinusoidal continuous variable speed modulation is used. The speed modulation parameters include amplitude ratio and frequency ratio. An RV factor representing energy is used to generate a series of modulation parameters arranged from smallest to largest energy. The modulation parameter with the lowest energy is selected as the first choice to generate a smooth continuous variable speed curve. If it is in the discrete variable speed dominant range, a stable target speed is calculated based on the phase difference matching condition. A discrete speed sequence is generated through low-pass filtering and saturation constraint processing. The discrete speed with the smallest difference from the preset spindle speed is selected as the target speed. S3: Monitor chatter online based on multi-source signal characteristics. If chatter is suppressed, maintain the current spindle speed and output a stable machining state until machining is completed. If chatter is not suppressed, proceed to step S2 and switch to the next set of parameter combinations for further control. For the continuous variable speed dominant region, select the next set of speed modulation parameters in order of energy from small to large. For the discrete variable speed dominant region, select the corresponding discrete speed as the target speed in order of the difference between the discrete speed and the preset spindle speed from small to large. The process of using sinusoidal continuous speed modulation in the continuously variable speed dominant region, optimizing the speed modulation parameters based on the energy minimization criterion, and generating a smooth speed curve includes the following steps: The rotational speed Ω during sinusoidal continuous speed modulation is expressed as: Ω=Ω0+Ω1sin(ω m t)=Ω0[1+RVA·sin(RVF·2πf0t)]; Where RVA = Ω1 / Ω0, RVF = 60f m / Ω0=f m / f0, Ω0 represents the magnitude of the nominal speed, Ω1 represents the magnitude of the speed change, ω m ω represents the angular frequency of the change in rotational speed. m =2πf m f m f0 represents the frequency of the main flutter when flutter occurs under the condition that the rotational speed is in the dominant region of continuous variable speed; RVA and RVF represent the amplitude ratio and frequency ratio, respectively; t represents time t. The speed modulation parameters are calculated based on the principle of minimum energy and are expressed as follows: in, In the formula, k0 represents the number of lobes in the stability lobe diagram; ε0 represents the phase difference between the vibration displacement of the current cutting tooth and the previous cutting tooth during milling; N t Indicates the number of teeth on the milling cutter; ω c The flutter angular frequency at which flutter occurs; m f The degree of modulation is indicated by calculating the local minimum of the 0th-order Bessel function of the first kind; The calculation results from the above formula contain a series of modulation parameters. To optimize these parameters and reduce machine tool energy consumption, an RV factor, representing energy, is introduced to sort the speed modulation parameters according to their energy levels. The RV factor is expressed as: RV = RVA·RVF; Based on parameter priority, the combination of speed modulation parameters with the smallest RV factor is selected to generate a continuous and smooth sinusoidal variable speed curve as the continuous variable speed curve.

2. The method for suppressing chatter during milling of thin-walled structural parts based on adaptive control of spindle speed parameters according to claim 1, characterized in that, The process of calculating a stable target speed based on phase difference matching conditions in the discrete variable speed dominant region, and generating a discrete speed sequence through low-pass filtering and saturation constraint processing, includes the following steps: The target rotational speed for stable machining is calculated based on the phase difference matching condition, ensuring that the phases of the modulated waves in two adjacent cuts are the same; the target rotational speed is expressed as: In the formula, k is the number of complete chatter waves contained between two consecutive cuts, and f c The main chatter frequency is calculated based on the vibration signal during machining when the rotational speed is in the discrete variable speed dominance region. The rotational speed is constrained by a low-pass filter and a saturation module to generate a discrete rotational speed sequence.

3. The method for suppressing chatter during milling of thin-walled structural parts based on adaptive control of spindle speed parameters according to claim 1, characterized in that, In step S3, the processing vibration signal is continuously collected, and the chatter characteristic frequency components contained therein are analyzed to determine whether the chatter has been effectively suppressed.

4. A chatter suppression device for milling thin-walled structural parts based on adaptive control of spindle speed parameters according to the method of claim 1, characterized in that, The device includes: The speed threshold setting module is used to construct a stability lobe diagram based on the dynamic characteristics of the workpiece during milling. It determines the critical threshold by calculating the critical stability value under the maximum allowable modulation parameter under continuous speed variation and comparing it with the critical value under normal speed. The speed division module determines the speed range to which the preset spindle speed belongs based on a critical threshold. The speed control module is used to select the corresponding speed control strategy based on the determined speed range, adjust the spindle speed in real time, and monitor the machining status. If the speed is in the continuous variable speed dominance range, sinusoidal continuous variable speed modulation is adopted. The speed modulation parameters include amplitude ratio and frequency ratio. The RV factor, which represents energy, is used to generate a series of modulation parameters arranged in ascending order of energy. The modulation parameter with the lowest energy is selected as the first choice to generate a smooth continuous variable speed curve. If the speed is in the discrete variable speed dominance range, the stable target speed is calculated based on the phase difference matching condition. The discrete speed sequence is generated through low-pass filtering and saturation constraint processing. The discrete speed with the smallest difference from the preset spindle speed is selected as the target speed. The chatter monitoring module monitors chatter online based on the characteristics of multi-source signals. If chatter is suppressed, the current spindle speed is maintained and a stable machining state is output until machining is completed. If chatter is not suppressed, the module switches to the speed control module and continues to control the next set of parameters. Specifically, for the continuous variable speed dominant region, the next set of speed modulation parameters is selected according to the energy from small to large. For the discrete variable speed dominant region, the corresponding discrete speed is selected as the target speed according to the difference between the discrete speed and the preset spindle speed from small to large.

5. An electronic device, characterized in that, include: One or more processors; A storage device for storing one or more programs, which, when executed by one or more processors, cause the one or more processors to implement the chatter suppression method for milling thin-walled structural parts based on adaptive control of spindle speed parameters as described in any one of claims 1-3.

6. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the program is executed by the processor, it implements the milling chatter suppression method for thin-walled structural parts based on adaptive control of spindle speed parameters as described in any one of claims 1-3.

Images