A dual-stroke fast tool servo control system

Abstract

This invention relates to the field of fast tool servo control technology, and in particular to a dual-stroke fast tool servo control system. It comprises a two-stage displacement control system with two identical displacement controllers. Each displacement controller consists of a parallel PI control module and an error compensation module. The PI control module generates a primary adjustment control signal based on the tracking error signal; the error compensation module includes an inverse function module and a time delay module. The former restores the error displacement drive signal, and the latter acquires historical displacement drive signals. The two-stage controllers control their respective displacement components, gradually reducing the tracking error. Initially, the PI control module uses a proportional term for rapid correction to ensure initial tracking accuracy of the high-frequency signal; the error compensation module directly compensates for the current error without delay, gradually learning to approximate the desired signal as the error converges. The two modules work together to avoid the delay problem of the integral term, ensuring continuous high-precision tracking of high-frequency periodic signals and improving machining accuracy.

Description

Technical Field

[0001] This invention relates to the field of fast tool servo control technology, and in particular to a dual-stroke fast tool servo control system. Background Technology

[0002] Fast-tool servo devices are a key technology for precision and ultra-precision machining of curved and micro-structured surfaces, and have become a crucial component of ultra-precision machine tools. Due to their high precision and other characteristics, fast-tool servo devices are widely used to achieve high-precision machining of surfaces and contours, thereby improving manufacturing levels in industrial and high-tech fields. They have been widely applied in laser fusion, aerospace, optics, instrumentation, and many other fields.

[0003] Existing high-precision and ultra-precision machining equipment primarily utilizes piezoelectric ceramics and flexible hinges as the fast-tool servo mechanism, coupled with corresponding PI (Proportional-Integral) control strategies to reduce tracking errors and ensure high machining accuracy. Driven by the PI control strategy, it exhibits high tracking performance for some low-frequency periodic signals, thus guaranteeing high machining accuracy.

[0004] However, for high-frequency periodic signals generated when machining surfaces that combine macro and micro elements (such as sinusoidal signals when machining microlens arrays), the rate of change is rapid, requiring the controller to quickly adjust the output to match the input changes. Although the proportional term in a PI control strategy can provide a fast response, the integral term introduces a delay because it requires time to accumulate errors and make corresponding adjustments. This delay makes the system less sensitive to rapidly changing signals, and as machining time continues, the system's tracking performance deteriorates significantly, resulting in large amplitude tracking errors and / or phase tracking errors, which in turn leads to a significant reduction in machining accuracy. Summary of the Invention

[0005] To address one of the aforementioned technical problems, the present invention adopts the following technical solution:

[0006] According to one aspect of the present invention, a dual-stroke fast-cutting servo control system is provided, applied to a dual-stroke fast-cutting servo device. The fast-cutting device includes a primary displacement component and a secondary displacement component arranged in series in the target displacement direction, the primary displacement component and the secondary displacement component being superimposed to form a total target displacement. The control system includes:

[0007] Two displacement controllers are used to generate displacement drive signals for the primary displacement component and the secondary displacement component, respectively. The input signal of the displacement controller corresponding to the primary displacement component is the tracking error signal between the desired displacement signal input by the fast-blade control system and the actual displacement signal output by the primary displacement component.

[0008] The input signal of the displacement controller corresponding to the secondary displacement component is: the tracking error signal of the primary displacement component and the tracking error signal between the actual displacement signal output by the secondary displacement component when the tracking error signal is the input signal;

[0009] The displacement controller includes a PI control module, an error compensation module, and a first signal addition / subtraction module; the PI control module and the error compensation module are connected in parallel, and the first signal addition / subtraction module is communicatively connected to the output terminals of the PI control module and the error compensation module, respectively.

[0010] The PI control module is used to generate the corresponding primary adjustment control signal based on the corresponding tracking error signal using the PI control strategy;

[0011] The error compensation module includes: an inverse function module and a time delay module;

[0012] The inverse function module is used to restore the tracking error signal to the error displacement drive signal input by the corresponding displacement component; the displacement component can be a first-level displacement component or a second-level displacement component; the tracking error signal and the error displacement drive signal have different signal types;

[0013] The delay module is used to acquire the historical displacement drive signal input to the corresponding displacement component when the tracking error signal is generated;

[0014] The first signal addition / subtraction module is used to superimpose the primary adjustment control signal, the error displacement drive signal, and the historical displacement drive signal input to the corresponding displacement component when generating the tracking error signal, to generate a new displacement drive signal input to the corresponding displacement component.

[0015] This invention has at least one of the following beneficial effects:

[0016] In this invention, two stages of displacement components are connected in series to achieve the total desired displacement, i.e., the total target displacement. Simultaneously, two identical displacement controllers are also set up in this system to control the first-stage displacement component to reduce the error between the actual displacement output and the desired displacement signal input by the fast-tool control system, and to control the second-stage displacement component to further compensate for and eliminate the error generated by the first-stage displacement component. This keeps the overall tracking error of the system at a low level, thereby improving machining accuracy.

[0017] Furthermore, in addition to the PI control module, the controller of this invention also includes an error compensation module connected in parallel, comprising an inverse function module and a time delay module. This module superimposes and integrates the currently generated displacement error and the historical displacement drive signal of the input displacement component corresponding to the error into a compensation signal. This compensation signal is then superimposed with the primary adjustment control signal generated by the PI control module to form a new displacement control signal. Since the error compensation module directly compensates for the current error entirely in the newly generated control signal, it can compensate for the error more directly and quickly, without introducing any delay.

[0018] And, as Figure 5 As shown, in the initial operating phase, the proportional term (P) of the PI control module immediately generates a control action based on the current error, providing instantaneous correction. Since the integral term (I) depends on the time accumulation of the error, its contribution in the initial stage is relatively small. Therefore, the PI control module can achieve high tracking accuracy in the initial tracking of high-frequency periodic signals. Simultaneously, the error compensation module more quickly and directly compensates for the current error. That is, in the initial stage, the error compensation module provides a larger and more direct compensation. Therefore, as the error converges to near zero (typically within tens of milliseconds), the control signal output by the error compensation module gradually approaches the desired signal. At the same time, as the error value gradually decreases to zero, the control signal output by the PI control module gradually approaches a constant value.

[0019] Therefore, as the error gradually decreases, the error compensation module gradually learns and approximates the desired control signal based on the currently generated displacement error and historical displacement drive signals. Its adjustment effect on the signal gradually increases, and because it does not introduce delay, it ensures higher tracking capability for high-frequency signals in the later stages. Correspondingly, since the PI control module generates an adjustment signal based on the error, its adjustment effect on the signal gradually decreases during this process. This ensures good tracking accuracy based on the error signal in the initial stage, while playing virtually no adjustment role in the later stages, avoiding delay introduced by the integral term. Thus, the error compensation module and the PI module in this system controller compensate and cooperate with each other, preventing a significant decline in the system's tracking performance as processing time continues, thereby ensuring the processing accuracy of high-frequency periodic signals. Attached Figure Description

[0020] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0021] Figure 1 This is a schematic diagram of a dual-stroke fast tool servo control system provided in an embodiment of the present invention;

[0022] Figure 2 This is a schematic diagram of the structure of the dual-stroke fast cutter servo device provided in an embodiment of the present invention;

[0023] Figure 3 This is an exploded view of the dual-stroke fast cutter servo device provided in an embodiment of the present invention;

[0024] Figure 4 This is a schematic diagram of the internal cutting structure of the dual-stroke fast cutter servo device provided in an embodiment of the present invention;

[0025] Figure 5 This is a schematic diagram showing the output signal trends of the PI control module (blue) and the error compensation module (red) in a dual-stroke fast-tool servo control system provided in an embodiment of the present invention, during the process of error convergence to near zero.

[0026] Figure Labels

[0027] 1. Primary displacement assembly; 10. First hinge body; 11. First hinge arm; 12. First piezoelectric ceramic; 13. Displacement base; 14. Sensor mounting slot; 15. Weight reduction through hole; 2. Secondary displacement assembly; 20. Second hinge body; 21. Second hinge arm; 22. Second piezoelectric ceramic; 3. Cutting head; 4. Displacement sensor bracket; 50. PI control module; 51. Inverse function module; 52. Time delay module; 53. Second signal addition / subtraction module; 54. Low-pass filter; 55. First signal addition / subtraction module; 56. Limiting module; 57. Third signal addition / subtraction module. Detailed Implementation

[0028] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0029] As one possible embodiment of the present invention, such as Figure 1 As shown, a dual-stroke fast tool servo control system is provided, which is applied to a dual-stroke fast tool servo device, such as... Figures 2 to 4 As shown, the fast-cutting device includes a primary displacement component 1 and a secondary displacement component 2 connected in series in the target displacement direction. The primary displacement component 1 and the secondary displacement component 2 are used to superimpose to form the total target displacement.

[0030] Specifically, such as Figures 2 to 4 As shown, the dual-stroke fast-tool servo device in this embodiment includes the following structure:

[0031] The primary displacement component 1 includes a displacement base 13, a first piezoelectric ceramic 12, and a first flexible hinge.

[0032] The first flexible hinge includes a first hinge body 10 and a plurality of first hinge arms 11 disposed on the side wall of the first hinge body 10.

[0033] The outer end of the first hinge arm 11 is fixedly connected to the displacement base 13. The displacement base 13 has a first driving chamber inside.

[0034] The first piezoelectric ceramic 12 is disposed in the first driving chamber. The two opposite ends of the first piezoelectric ceramic 12 abut against the inner wall of the displacement base 13 and the bottom of the first hinge body 10, respectively. The first piezoelectric ceramic 12 is used to control the two opposite ends to undergo corresponding deformation in the target displacement direction according to the input voltage control signal.

[0035] In the fast servo tool post (i.e., the dual-stroke fast tool servo device of this embodiment), the flexible hinge is mainly used to enhance the dynamic performance and machining accuracy of the tool post. A flexible hinge is a mechanical component that uses the elastic deformation of a material to achieve motion transmission. Specifically, in this embodiment, the first hinge body 10 has an external cuboid shape, with corresponding first hinge arms 11 fixedly mounted on its four sides. Furthermore, the first hinge arms 11 have weight-reducing through holes 15 to reduce the stiffness of the first hinge arms 11 in the desired direction, allowing the first hinge arms 11 to move more easily in that direction. Simultaneously, it maintains the corresponding stiffness in directions where deformation is not desired (such as the hinge torsion direction caused by cutting force). This ensures that when the first flexible hinge executes the corresponding displacement command, the first hinge arms 11 can more accurately undergo the corresponding stroke deformation while maintaining the corresponding stiffness. In this embodiment, the flexible hinge can be made of aluminum.

[0036] In fast-actuator servo mechanisms, piezoelectric ceramics are primarily used to achieve high-precision position control and rapid response. Based on the piezoelectric effect, piezoelectric ceramics generate a corresponding degree of displacement in the desired direction by receiving a corresponding voltage drive signal.

[0037] like Figures 2 to 4 As shown, the secondary displacement component 2 includes a second piezoelectric ceramic 22 and a second flexible hinge.

[0038] The second flexible hinge includes a second hinge body 20 and a plurality of second hinge arms 21 disposed on the side wall of the second hinge body 20. A cutting head 3 is fixedly disposed on the second hinge body 20.

[0039] The second hinge arm 21 is fixedly connected to the first hinge body 10. The first hinge body 10 has a second drive chamber inside.

[0040] The second piezoelectric ceramic 22 is disposed in the second driving chamber. The two opposite ends of the second piezoelectric ceramic 22 abut against the inner wall of the first hinge body 10 and the bottom of the second hinge body 20, respectively. The second piezoelectric ceramic 22 is used to control the two opposite ends to undergo corresponding deformation in the target displacement direction according to the input voltage control signal.

[0041] Correspondingly, the structure of the secondary displacement component 2 is basically the same as that of the primary displacement component 1. The secondary displacement component 2 is installed on the movable part (first hinge body 10) of the primary displacement component 1, and is used to continue displacement based on the movement of the primary displacement component 1. In this embodiment, the motion structures between the two displacement components are independent and decoupled from each other, so that they can be controlled separately by two controllers. The control strategies do not affect each other, making it simpler.

[0042] Specifically, the displacement base 13, the first piezoelectric ceramic 12, the second piezoelectric ceramic 22, and the first hinge body 10 are all hollow structures.

[0043] like Figures 2 to 4 As shown, the fast-cutting device also includes: a displacement sensor bracket 4, a first displacement sensor, and a second displacement sensor.

[0044] The displacement sensor bracket 4 is inserted into the clamping channel formed by the displacement base 13, the first piezoelectric ceramic 12, the second piezoelectric ceramic 22, and the internal cavity of the first hinge body 10. The displacement sensor bracket 4 has a hollow structure.

[0045] The first displacement sensor is fixedly installed inside the displacement sensor bracket 4 to obtain displacement information L1 between the second hinge body 20 and the displacement base 13, that is, the total displacement of the two-stage displacement components.

[0046] The second displacement sensor is installed in the sensor mounting groove 14 on the displacement base 13 to obtain the displacement information L2 between the first hinge body 10 and the displacement base 13, that is, the displacement of the first-stage displacement component 1.

[0047] In the dual-stroke fast-tool servo device of this embodiment, since the space between the first hinge body 10 and the second hinge body 20 is small, it is not convenient to install corresponding displacement sensors to measure the relative displacement between them. Therefore, in this embodiment, corresponding displacement sensors are installed on the inner and outer sides of the displacement base 13, where displacement sensors can be easily installed, to obtain L1 and L2. The relative displacement between the first hinge body 10 and the second hinge body 20, that is, the displacement L3 of the secondary displacement component 2, can be obtained by L1-L2. Thus, while obtaining L2 and L3, the compactness of the dual-stroke fast-tool servo device structure is also ensured.

[0048] like Figure 1 As shown, the control system in this embodiment includes:

[0049] Two displacement controllers are used to generate displacement drive signals for the primary displacement component 1 and the secondary displacement component 2, respectively. Specifically, in this embodiment, the drive components for both the primary displacement component 1 and the secondary displacement component 2 are piezoelectric ceramics, and the displacement drive signals are voltage signals.

[0050] The input signal of the displacement controller corresponding to the first-level displacement component 1 is the tracking error signal between the desired displacement signal input by the fast-blade control system and the actual displacement signal output by the first-level displacement component 1.

[0051] The input signal of the displacement controller corresponding to the secondary displacement component 2 is: the tracking error signal of the primary displacement component 1 and the tracking error signal between the actual displacement signal output by the secondary displacement component 2 when the tracking error signal is the input signal.

[0052] Specifically, this system also includes: a third signal addition / subtraction module 57.

[0053] The third signal addition / subtraction module 57 is used to generate a corresponding tracking error signal based on the expected displacement signal input to the corresponding displacement component and the actual displacement signal output. In this embodiment, different error signals input to the displacement controller can be generated by setting the corresponding third signal addition / subtraction module 57.

[0054] In this embodiment, the primary displacement component 1 is used to achieve the main tracking of the desired displacement. Therefore, when its corresponding displacement controller performs control, the error signal it targets is the tracking error signal between the desired displacement signal input by the fast-sweep control system and the actual displacement signal output by the primary displacement component 1. Thus, by minimizing the error, the displacement output by the primary displacement component 1 can basically reach the desired displacement amount. However, in actual use, the displacement output by the primary displacement component 1 often does not completely match the desired displacement, meaning there will still be some error. Therefore, the secondary displacement component 2 in this embodiment is used to further optimize and compensate for the error generated by the primary displacement component 1, further reducing the error value between the final generated total displacement and the desired displacement. Therefore, the error value generated by the primary displacement component 1 is directly introduced into the displacement controller corresponding to the secondary displacement component 2, so that the displacement controller uses the error feedback from this error value to make the secondary displacement component 2 as close as possible to the displacement amount represented by the error value generated by the primary displacement component 1.

[0055] The displacement controller includes a PI control module 50, an error compensation module, and a first signal addition / subtraction module 55. The PI control module 50 and the error compensation module are connected in parallel, and the first signal addition / subtraction module 55 is communicatively connected to the output terminals of both the PI control module 50 and the error compensation module.

[0056] The PI control module 50 is used to generate a corresponding primary adjustment control signal based on the corresponding tracking error signal using a PI control strategy.

[0057] Specifically, taking the displacement error obtained at the current time t as an example, the primary adjustment control signal E(t) generated by the PI control strategy satisfies the following condition:

[0058] ;

[0059] Among them, K p It is the proportional gain, which determines the strength of the proportional term's response to error. K i The integral gain determines the rate at which the integral term accumulates error.

[0060] The error compensation module includes: inverse function module 51 and time delay module 52.

[0061] The inverse function module 51 is used to restore the tracking error signal to the error displacement drive signal input to the corresponding displacement component. The displacement component is either a first-level displacement component 1 or a second-level displacement component 2. The tracking error signal and the error displacement drive signal have different signal types. Specifically, the primary adjustment control signal, the error displacement drive signal, and the historical displacement drive signal are all voltage signals.

[0062] The delay module 52 is used to acquire the historical displacement drive signal input to the corresponding displacement component when generating the tracking error signal.

[0063] Since both the system's input and output are displacement signals, the resulting tracking error is also a displacement signal. The displacement controller ultimately outputs a drive signal, i.e., a voltage signal, to move the piezoelectric ceramic. Therefore, an inverse function module 51 is needed to convert the error signal into a corresponding voltage signal.

[0064] In this embodiment, existing technology can be used to establish transfer function models P corresponding to the first-stage displacement component 1 and the second-stage displacement component 2, respectively, to simulate the relationship between the inputs and outputs of the first-stage displacement component 1 and the second-stage displacement component 2, respectively. Then, the corresponding inverse function model P is obtained based on the transfer function model P. -1 That is, the inverse function module 51.

[0065] Theoretically P×P -1 =1, but in actual construction, the theoretically perfect state cannot be achieved. Usually, P and P -1 There is a delay term Z. -d Therefore, the error value of the voltage form after conversion by the inverse function module 51 also has a certain time delay. That is, the voltage error may be the error value generated by the previous one or several control signals. Therefore, in order to obtain the historical displacement drive signal corresponding to the time when the error value of the voltage form is greater than that, it is necessary to set the time delay module 52 to obtain the corresponding drive signal from the historical control data to ensure the consistency between the error and the drive signal and avoid the misalignment of the error and the drive signal, which would lead to the adjustment misalignment problem.

[0066] Specifically, taking the displacement error obtained at the current time t as an example, the error displacement driving signal V generated by the inverse function module 51 is explained. e(t) It simply converts the displacement signal into a voltage signal. The time delay module 52 acquires the signal related to V. e(t) The corresponding historical displacement driving signal u(t).

[0067] The first signal addition / subtraction module 55 is used to superimpose the primary adjustment control signal, the error displacement drive signal, and the historical displacement drive signal input by the corresponding displacement component when generating the tracking error signal, to generate a new displacement drive signal input by the corresponding displacement component.

[0068] That is, the new displacement driving signal W=u(t)+V e(t) +E(t).

[0069] Furthermore, the displacement controller also includes a limiting module 56.

[0070] The amplitude limiting module 56 is communicatively connected to the first signal addition / subtraction module 55 and is used to limit the amplitude of the new displacement driving signal within a preset amplitude range.

[0071] The limiting module 56 can be a bandpass filter. By setting the corresponding cutoff frequency, it can ensure that the final output displacement drive signal conforms to the amplitude setting of the corresponding input signal of the piezoelectric ceramic.

[0072] During the process of the displacement controller converging the error to near zero (typically within tens of milliseconds), it actually works by adjusting the V in the error compensation module. e(t) The error is jointly adjusted by the E(t) generated by the PI control strategy. Specifically, as the error value e(t) gradually decreases to zero, the control signal (K) output by the PI control module 50... p e(t) approaches zero. The value gradually approaches a constant value. Correspondingly, the control signal output by the error compensation module (i.e., u(t) + V) gradually approaches a constant value. e(t) Then it gradually approaches the desired signal.

[0073] like Figure 5 As shown, as the error gradually decreases, the error compensation module gradually learns and approximates the desired control signal based on the currently generated displacement error and historical displacement drive signals. Its adjustment effect on the signal gradually increases from weak to strong. Because it does not introduce delay, it ensures higher tracking capability for high-frequency signals in the later stages. Correspondingly, since the PI control module 50 generates an adjustment signal based on the error, its adjustment effect on the signal gradually decreases from strong to weak during this process. This ensures good tracking accuracy based on the error signal in the initial stage, while playing virtually no adjustment role in the later stages, avoiding delay introduced by the integral term. Therefore, the error compensation module and the PI module in this system controller compensate and cooperate with each other, preventing a significant decrease in the system's tracking performance as processing time continues, thus ensuring the processing accuracy of high-frequency periodic signals.

[0074] In one possible embodiment of the present invention, the error compensation module further includes:

[0075] The second signal addition / subtraction module 53 and the low-pass filter 54.

[0076] The second signal addition / subtraction module 53 is used to superimpose the error displacement drive signal and the historical displacement drive signal to generate a hybrid adjustment control signal.

[0077] The low-pass filter 54 is used to remove signals with frequencies greater than the preset cutoff frequency from the mixed adjustment control signal and generate the primary and secondary adjustment control signals.

[0078] Since the primary displacement component 1 and the secondary displacement component 2 are inevitably affected by environmental noise during actual motion execution, such as resonance of other components, the actual displacement signal of the displacement component obtained in this embodiment inevitably contains some environmental noise information. Therefore, the final generated e(t) and Ve(t) will contain this environmental noise. Since this noise is usually high-frequency noise, it can be removed by setting a low-pass filter 54 in the error compensation module to improve the accuracy of the signal.

[0079] Correspondingly, in this embodiment, the function of the first signal addition / subtraction module 55 is replaced by: superimposing the primary adjustment control signal and the secondary adjustment control signal to generate a new displacement drive signal input to the corresponding displacement component.

[0080] As another possible embodiment of the present invention, the control system further includes: a trajectory analysis module, which is used to perform the following steps:

[0081] S100: Performs a Fast Fourier Transform on the tool path to be machined, generating a spectrum diagram corresponding to the tool path. The spectrum diagram includes all frequency components contained in the tool path.

[0082] S200: If there is only one frequency component in the spectrum with an amplitude greater than the preset amplitude threshold and a signal frequency greater than the preset frequency threshold, then the displacement signal corresponding to the tool trajectory to be processed will be used as the desired displacement signal input to the fast tool control system.

[0083] The preset amplitude threshold and preset frequency threshold in this embodiment can be set according to the actual usage scenario.

[0084] S300: If there are at least two frequency components in the spectrum with amplitudes greater than the preset amplitude threshold, an alarm signal is generated.

[0085] For a true single-frequency periodic signal, the peak in the spectrum should be very prominent and concentrated, with almost no other significant energy distribution around it. Therefore, a preset amplitude threshold can be used to filter and determine whether the tool path to be processed is a single-frequency periodic signal. Simultaneously, the signal frequency can be determined using a preset frequency threshold. Thus, the trajectory analysis module can determine in advance whether the current tool path to be processed is a high-frequency single-frequency periodic signal more suitable for the machining process of this system.

[0086] Furthermore, the above figures are merely illustrative of the processes included in a control system according to exemplary embodiments of the present invention, and are not intended to be limiting. It is readily understood that the processes shown in the above figures do not indicate or limit the temporal order of these processes. Additionally, it is readily understood that these processes may be executed synchronously or asynchronously, for example, in multiple modules.

[0087] It should be noted that although several modules or units for the device used to perform actions have been mentioned in the detailed description above, this division is not mandatory. In fact, according to embodiments of this disclosure, the features and functions of two or more modules or units described above can be embodied in one module or unit. Conversely, the features and functions of one module or unit described above can be further divided and embodied by multiple modules or units.

[0088] The above are merely specific embodiments of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A dual-stroke fast-cutting servo control system, applied to a dual-stroke fast-cutting servo device, the fast-cutting servo device comprising a primary displacement component and a secondary displacement component connected in series in the target displacement direction, the primary displacement component and the secondary displacement component being superimposed to form a total target displacement; characterized in that, The control system includes: Two displacement controllers are used to generate displacement drive signals for a primary displacement component and a secondary displacement component, respectively. The input signal of the displacement controller corresponding to the primary displacement component is the tracking error signal between the desired displacement signal input by the fast-blade control system and the actual displacement signal output by the primary displacement component. The input signal of the displacement controller corresponding to the secondary displacement component is: the tracking error signal of the primary displacement component and the tracking error signal between the actual displacement signal output by the secondary displacement component when the tracking error signal is the input signal; The displacement controller includes a PI control module, an error compensation module, and a first signal addition / subtraction module; the PI control module and the error compensation module are connected in parallel, and the first signal addition / subtraction module is communicatively connected to the output terminals of the PI control module and the error compensation module, respectively. The PI control module is used to generate a corresponding primary adjustment control signal based on the corresponding tracking error signal using a PI control strategy; the primary adjustment control signal E(t) satisfies the following condition: ； Among them, K p It is the proportional gain, which determines the strength of the proportional term's response to error; K i The integral gain determines the rate at which the integral term accumulates error. The error compensation module includes: an inverse function module and a time delay module; The inverse function module is used to restore the tracking error signal to the error displacement drive signal input by the corresponding displacement component; the displacement component is a first-level displacement component or a second-level displacement component; the tracking error signal and the error displacement drive signal have different signal types; The time delay module is used to acquire the historical displacement drive signal input to the corresponding displacement component when the tracking error signal is generated; The first signal addition / subtraction module is used to superimpose the primary adjustment control signal, the error displacement drive signal, and the historical displacement drive signal input to the corresponding displacement component when generating the tracking error signal to generate a new displacement drive signal input to the corresponding displacement component. The trajectory analysis module is used to perform the following steps: A fast Fourier transform is performed on the tool path to be machined to generate a spectrum diagram corresponding to the tool path; the spectrum diagram includes all frequency components included in the tool path. If there is only one frequency component in the spectrum whose amplitude is greater than a preset amplitude threshold and whose signal frequency is greater than a preset frequency threshold, then the displacement signal corresponding to the trajectory of the tool to be processed is taken as the expected displacement signal input to the fast tool control system.

2. The control system according to claim 1, characterized in that, The error compensation module further includes: Second signal addition / subtraction module and low-pass filter; The second signal addition / subtraction module is used to superimpose the error displacement driving signal and the historical displacement driving signal to generate a hybrid adjustment control signal; The low-pass filter is used to remove signals with frequencies greater than the preset cutoff frequency from the mixed adjustment control signal and generate primary and secondary adjustment control signals. The function of the first signal addition / subtraction module is replaced by: superimposing the primary adjustment control signal and the secondary adjustment control signal to generate a new displacement drive signal input to the corresponding displacement component.

3. The control system according to claim 1, characterized in that, The displacement controller also includes: a limiting module; The amplitude limiting module is communicatively connected to the first signal addition / subtraction module and is used to limit the amplitude of the new displacement driving signal within a preset amplitude range.

4. The control system according to claim 1, characterized in that, Also includes: Third signal addition / subtraction module; The third signal addition / subtraction module is used to generate a corresponding tracking error signal based on the expected displacement signal input by the corresponding displacement component and the actual displacement signal output.

5. The control system according to claim 1, characterized in that, After generating the spectrum diagram corresponding to the tool path to be machined, the path analysis module is further configured to perform the following steps: If there are at least two frequency components in the spectrum whose amplitude is greater than a preset amplitude threshold, an alarm signal is generated.

6. The control system according to claim 1, characterized in that, The primary adjustment control signal, error displacement drive signal, and historical displacement drive signal are all voltage signals.

7. The control system according to claim 1, characterized in that, The primary displacement assembly includes a displacement base, a first piezoelectric ceramic, and a first flexible hinge. The first flexible hinge includes a first hinge body and a plurality of first hinge arms disposed on the side wall of the first hinge body; The outer end of the first hinge arm is fixedly connected to the displacement base; the displacement base is provided with a first driving chamber. The first piezoelectric ceramic is disposed in the first driving chamber, and the two opposite ends of the first piezoelectric ceramic abut against the inner wall of the displacement base and the bottom of the first hinge body, respectively. The first piezoelectric ceramic is used to control the two opposite ends to undergo corresponding deformation in the target displacement direction according to the input voltage control signal.

8. The control system according to claim 7, characterized in that, The secondary displacement component includes a second piezoelectric ceramic and a second flexible hinge; The second flexible hinge includes a second hinge body and a plurality of second hinge arms disposed on the side wall of the second hinge body; The second hinge arm is fixedly connected to the first hinge body; the first hinge body has a second drive chamber inside; The second piezoelectric ceramic is disposed in the second driving chamber. The two opposite ends of the second piezoelectric ceramic abut against the inner wall of the first hinge body and the bottom of the second hinge body, respectively. The second piezoelectric ceramic is used to control the two opposite ends to undergo corresponding deformation in the target displacement direction according to the input voltage control signal.

9. The control system according to claim 8, characterized in that, The displacement base, the first piezoelectric ceramic, the second piezoelectric ceramic, and the main body of the first hinge are all hollow structures. The fast-blade servo device also includes: a displacement sensor bracket, a first displacement sensor, and a second displacement sensor; The displacement sensor bracket is inserted into a clamping channel formed by the displacement base, the first piezoelectric ceramic, the second piezoelectric ceramic, and the internal cavity of the first hinge body; the displacement sensor bracket has a hollow structure. The first displacement sensor is fixedly installed in the displacement sensor bracket and is used to obtain displacement information between the second hinge body and the displacement base; The second displacement sensor is mounted on the displacement base to obtain displacement information between the first hinge body and the displacement base.

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