Double-stroke fast tool servo control system

Abstract

The invention relates to the technical field of fast tool servo control, in particular to a double-stroke fast tool servo control system. And the two-stage displacement control system comprises two same displacement controllers. Each displacement controller is composed of a PI control module and an error compensation module which are connected in parallel. The PI control module generates a primary adjustment control signal according to the tracking error signal; the error compensation module comprises an inverse function module and a time delay module, the inverse function module restores the error displacement driving signal, and the time delay module obtains the historical displacement driving signal. Two-stage controllers of the system respectively control corresponding displacement assemblies, and tracking errors are gradually reduced. The PI control module ensures the initial tracking precision of the high-frequency signal through proportional quick correction at the initial stage; the error compensation module directly compensates the current error without delay, and gradually learns and approaches the expected signal along with error convergence. The two are matched to avoid the problem of integral term delay, continuous high-precision tracking of high-frequency periodic signals is ensured, and the machining precision is improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of fast tool servo control, in particular to a double-stroke fast tool servo control system. BACKGROUND

[0002] The fast tool servo device is one of the key technologies for precise and ultra-precise curved surface and microstructure surface processing, and has become one of the key components of ultra-precise machine tools. It has the characteristics of high precision, etc., so the fast tool servo device is widely used to realize high-precision machined surfaces and contour accuracy, and to improve the manufacturing level in the industrial and high-precision fields. It has been widely used in laser fusion, aerospace, optics, instruments and other fields.

[0003] The fast tool servo device in the existing precise and ultra-precise machining equipment is mainly in the form of piezoelectric ceramic and flexible hinge, and is matched with the corresponding PI (Proportional-Integral) control strategy to reduce the tracking error and ensure high machining precision. Under the driving of the PI control strategy, it has high tracking performance for some low-frequency periodic signals, which can ensure high machining precision.

[0004] However, for high-frequency periodic signals generated when machining some macro-micro combined surfaces (such as sinusoidal signals when machining micro-lens arrays), the change rate is fast, and the controller is required to quickly adjust the output to match the change of the input. Although the proportional term in the PI control strategy can provide a faster response, the integral term will introduce a delay because it needs time to accumulate errors and make corresponding adjustments. This delay makes the system less sensitive to rapidly changing signals, and as the machining time continues, the tracking performance of the system will be greatly reduced, resulting in large amplitude tracking error and / or phase tracking error, and thus leading to a significant reduction in machining precision. SUMMARY

[0005] To solve one of the above technical problems, the technical solution adopted by the present application is: According to one aspect of the present application, a double-stroke fast tool servo control system is provided, which is applied to a double-stroke fast tool servo device. The fast tool device includes a first displacement component and a second displacement component arranged in series in the target displacement direction, and the first displacement component and the second displacement component are used to superimpose the total target displacement amount; the control system comprises: Two displacement controllers, the two displacement controllers are respectively used to generate displacement driving signals of the first displacement component and the second displacement component; the input signal of the displacement controller corresponding to the first displacement component is the tracking error signal between the expected displacement signal input by the fast tool control system and the actual displacement signal output by the first displacement component corresponding to the first displacement component; The input signal of the displacement controller corresponding to the secondary displacement assembly is: the tracking error signal of the primary displacement assembly, and the tracking error signal between the actual displacement signal output by the secondary displacement assembly and the tracking error signal when the tracking error signal is the input signal; The displacement controller comprises a PI control module, an error compensation module and a first signal addition and subtraction module; the PI control module and the error compensation module are arranged in parallel; and the first signal addition and subtraction module is in communication connection with the output ends of the PI control module and the error compensation module respectively; The PI control module is used for generating a corresponding primary adjustment control signal by using a PI control strategy according to the corresponding tracking error signal; The error compensation module comprises an inverse function module and a time delay module; The inverse function module is used for restoring the tracking error signal into an error displacement driving signal input by the corresponding displacement assembly; the displacement assembly is a primary displacement assembly or a secondary displacement assembly; the signal types of the tracking error signal and the error displacement driving signal are different; The time delay module is used for obtaining a historical displacement driving signal input by the corresponding displacement assembly when the tracking error signal is generated; The first signal addition and subtraction module is used for superimposing the primary adjustment control signal, the error displacement driving signal and the historical displacement driving signal input by the corresponding displacement assembly when the tracking error signal is generated to generate a new displacement driving signal input by the corresponding displacement assembly.

[0006] The present application has at least one of the following beneficial effects: In the present application, two-stage displacement assemblies are arranged in series to superimpose and realize the total desired displacement, i.e., the total target displacement. Meanwhile, two identical displacement controllers are arranged in the present system to control the primary displacement assembly to reduce the error between the actual displacement output by the primary displacement assembly and the desired displacement signal input by the fast knife control system, control the secondary displacement assembly to further compensate and eliminate the error generated by the primary displacement assembly, and thus keep the tracking error of the whole system at a low level to improve the machining precision.

[0007] In addition, in the controller of the present application, an error compensation module comprising an inverse function module and a time delay module is arranged in parallel on the basis of the PI control module. The module superimposes and integrates the current displacement error and the historical displacement driving signal of the input displacement assembly corresponding to the error to form a compensation signal, and then superimposes 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 the current error to the newly generated control signal, the error can be compensated more directly and rapidly without delay.

[0008] Moreover, as Figure 5As shown, in the initial stage of the initial work, the proportional term (P) in the PI control module will immediately generate a control action according to the current error, providing immediate correction force. Since the integral term (I) depends on the time accumulation of the error, its contribution in the initial stage is relatively small. Thus, the PI control module can have higher tracking accuracy when tracking high-frequency periodic signals in the initial stage. At the same time, the error compensation module will also more directly compensate for the current error. That is, the error compensation module compensates for the error more directly in the initial stage. Therefore, in the process of error convergence to near zero (usually tens of milliseconds), the control signal output by the error compensation module gradually approaches the desired signal. At the same time, since the error value gradually decreases to zero, the control signal output by the PI control module gradually approaches a constant value.

[0009] Therefore, in the process of gradually reducing the error, the error compensation module gradually learns and approaches the desired control signal based on the current displacement error and the historical displacement driving signal, and its signal adjustment gradually weakens. Also, it does not introduce delay to ensure higher tracking ability for high-frequency signals in the subsequent process. Correspondingly, since the PI control module generates a regulation signal based on the error, its signal adjustment gradually weakens in the process to ensure better tracking accuracy based on the error signal in the initial stage, and to avoid the delay introduced by the integral term in the later stage. Thus, the error compensation module and the PI module in the system controller complement each other, which can avoid the problem of significant decline in tracking performance of the system as the processing time continues, thereby ensuring the processing accuracy of high-frequency periodic signals. BRIEF DESCRIPTION OF DRAWINGS

[0010] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following will briefly introduce the drawings needed in the embodiment description. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative labor.

[0011] Figure 1 A structural schematic diagram of a double-stroke fast knife servo control system provided by an embodiment of the present application is shown in the figure. Figure 2 A structural schematic diagram of a double-stroke fast knife servo device provided by an embodiment of the present application is shown in the figure. Figure 3 An exploded structural schematic diagram of a double-stroke fast knife servo device provided by an embodiment of the present application is shown in the figure. Figure 4 An internal cutaway structural schematic diagram of a double-stroke fast knife servo device provided by an embodiment of the present application is shown in the figure. Figure 5A schematic diagram of the output signal trend of the PI control module (blue) and the error compensation module (red) in the process of error convergence to near zero is provided in a double-stroke fast tool servo control system of an embodiment of the present application.

[0012] Reference signs 1, primary displacement assembly; 10, first hinge body; 11, first hinge arm; 12, first piezoelectric ceramic; 13, displacement base; 14, sensor mounting groove; 15, weight reduction through hole; 2, secondary displacement assembly; 20, second hinge body; 21, second hinge arm; 22, second piezoelectric ceramic; 3, cutting tool head; 4, displacement sensor support; 50, PI control module; 51, inverse function module; 52, time delay module; 53, second signal addition and subtraction module; 54, low-pass filter; 55, first signal addition and subtraction module; 56, amplitude limiting module; 57, third signal addition and subtraction module. DETAILED DESCRIPTION

[0013] The technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the present application.

[0014] As a possible embodiment of the present application, as shown in Figure 1 , a double-stroke fast tool servo control system is provided, which is applied to a double-stroke fast tool servo device, as shown in Figures 2 to 4 , the fast tool device includes a primary displacement assembly 1 and a secondary displacement assembly 2 arranged in series in a target displacement direction, and the primary displacement assembly 1 and the secondary displacement assembly 2 are used to superimpose a total target displacement amount.

[0015] Specifically, as shown in Figures 2 to 4 , the double-stroke fast tool servo device in the embodiment includes the following structure: The primary displacement assembly 1 includes a displacement base 13, a first piezoelectric ceramic 12, and a first flexible hinge.

[0016] The first flexible hinge includes a first hinge body 10 and a plurality of first hinge arms 11 arranged on the side wall of the first hinge body 10.

[0017] The outer end of the first hinge arm 11 is fixedly connected with the displacement base 13. The displacement base 13 is internally provided with a first driving chamber.

[0018] The first piezoelectric ceramic 12 is arranged in the first driving chamber, and two opposite ends of the first piezoelectric ceramic 12 are respectively arranged against the inner wall of the displacement base 13 and the bottom of the first hinge body 10, and the first piezoelectric ceramic 12 is used to control corresponding deformation of the two opposite ends in the target displacement direction according to an input voltage control signal.

[0019] In the rapid servo tool holder (i.e., the double-stroke rapid tool servo device in the embodiment), the flexible hinge is mainly used to enhance the dynamic performance and machining precision of the tool holder. The flexible hinge is a mechanical element that uses the elastic deformation of a material to realize motion transmission. Specifically, in the embodiment, the first hinge body 10 has a cuboid shape, and corresponding first hinge arms 11 are fixedly arranged on four sides of the first hinge body 10. In addition, the first hinge arms 11 are provided with weight-reducing through holes 15 to reduce the stiffness of the first hinge arms 11 in the desired direction, so that the first hinge arms 11 can more conveniently displace in the desired direction. At the same time, the corresponding stiffness is maintained in the direction in which deformation is not expected to occur (e.g., the hinge twist direction caused by the cutting force). Thus, when the first flexible hinge executes a corresponding displacement instruction, the first hinge arms 11 can more accurately deform in the corresponding stroke under the premise of ensuring the corresponding stiffness. The material of the flexible hinge in the embodiment can be aluminum.

[0020] In the rapid tool servo mechanism, the piezoelectric ceramic is mainly used to realize high-precision position control and rapid response. The piezoelectric ceramic is based on the piezoelectric effect and generates a corresponding degree of displacement in the desired direction by receiving a corresponding voltage driving signal.

[0021] As shown in FIG. 1, the secondary displacement assembly 2 includes a second piezoelectric ceramic 22 and a second flexible hinge. Figures 2 to 4

[0022] The second flexible hinge includes a second hinge body 20 and a plurality of second hinge arms 21 arranged on the side wall of the second hinge body 20. The second hinge body 20 is fixedly provided with a cutting tool head 3.

[0023] The second hinge arms 21 are fixedly connected to the first hinge body 10. The first hinge body 10 is internally provided with a second driving chamber.

[0024] The second piezoelectric ceramic 22 is arranged in the second driving chamber, and two opposite ends of the second piezoelectric ceramic 22 are respectively arranged against the inner wall of the first hinge body 10 and the bottom of the second hinge body 20, and the second piezoelectric ceramic 22 is used to control corresponding deformation of the two opposite ends in the target displacement direction according to an input voltage control signal.

[0025] ​Correspondingly, the structure of the second displacement assembly 2 is basically the same as that of the first displacement assembly 1. The second displacement assembly 2 is installed on the movable part (the first hinge body 10) of the first displacement assembly 1, and is used to continue displacement on the basis of the movement of the first displacement assembly 1. In this embodiment, the movement structures between the two displacement assemblies are independent and decoupled from each other, so as to be controlled by two controllers respectively in the subsequent use, the control strategies do not affect each other, and it is more simple.

[0026] 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.

[0027] As shown in Figures 2 to 4 , the fast tool device further includes a displacement sensor support 4, a first displacement sensor and a second displacement sensor.

[0028] The displacement sensor support 4 is arranged in the clamping channel formed by the internal cavities of the displacement base 13, the first piezoelectric ceramic 12, the second piezoelectric ceramic 22 and the first hinge body 10. The displacement sensor support 4 is a hollow structure.

[0029] The first displacement sensor is fixedly arranged in the displacement sensor support 4, and is used to obtain the displacement information L1 between the second hinge body 20 and the displacement base 13, that is, the total displacement of the two displacement assemblies.

[0030] The second displacement sensor is arranged in the sensor mounting groove 14 on the displacement base 13, and is used to obtain the displacement information L2 between the first hinge body 10 and the displacement base 13, that is, the displacement of the first displacement assembly 1.

[0031] In the double-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 the corresponding displacement sensor to measure the relative displacement between the two. Therefore, in this embodiment, corresponding displacement sensors are installed on the inner and outer sides of the displacement base 13 which is easy to install displacement sensors to obtain L1 and L2, and the relative displacement between the first hinge body 10 and the second hinge body 20, that is, the displacement L3 of the second displacement assembly 2, can be obtained by L1-L2. Thus, on the basis of obtaining L2 and L3, the compactness of the double-stroke fast tool servo device structure is also ensured.

[0032] As shown in Figure 1 , the control system in this embodiment includes: Two displacement controllers, the two displacement controllers are respectively used to generate displacement driving signals of the first displacement assembly 1 and the second displacement assembly 2. Specifically, in this embodiment, the driving components of the first displacement assembly 1 and the second displacement assembly 2 are both piezoelectric ceramics, and the displacement driving signals are voltage signals.

[0033] The input signal of the displacement controller corresponding to the first displacement component 1 is a tracking error signal between the expected displacement signal input by the fast tool control system and the actual displacement signal output by the first displacement component 1.

[0034] The input signal of the displacement controller corresponding to the second displacement component 2 is a tracking error signal between the tracking error signal of the first displacement component 1 and the actual displacement signal output by the second displacement component 2 when the tracking error signal is the input signal.

[0035] Specifically, the system further comprises a third signal addition and subtraction module 57.

[0036] The third signal addition and subtraction module 57 is configured to generate a corresponding tracking error signal according to the expected displacement signal input by the corresponding displacement component and the actual displacement signal output by the corresponding displacement component. In the embodiment, different error signals input by the displacement controller can be generated by setting corresponding third signal addition and subtraction modules 57.

[0037] In the embodiment, the first displacement component 1 is configured to realize the main tracking of the expected displacement, so when the corresponding displacement controller is controlled, the error signal is the tracking error signal between the expected displacement signal input by the fast tool control system and the actual displacement signal output by the first displacement component 1. Thus, by eliminating the error as much as possible, the displacement output by the first displacement component 1 can basically reach the expected displacement. However, in actual use, the displacement output by the first displacement component 1 often does not completely coincide with the expected displacement, that is, there is still a certain error. Therefore, the second displacement component 2 in the embodiment is used to further optimize and compensate for the error generated by the first displacement component 1, so as to further reduce the error value between the total displacement generated and the expected displacement. Therefore, the error value generated by the first displacement component 1 is directly introduced into the displacement controller corresponding to the second displacement component 2, so that the displacement controller uses the error feedback by the error value to make the second displacement component 2 approach the displacement amount represented by the error value generated by the first displacement component 1 as much as possible.

[0038] The displacement controller comprises a PI control module 50, an error compensation module, and a first signal addition and subtraction module 55. The PI control module 50 and the error compensation module are connected in parallel, and the first signal addition and subtraction module 55 is in communication connection with the output ends of the PI control module 50 and the error compensation module.

[0039] The PI control module 50 is configured to generate a corresponding primary adjustment control signal using a PI control strategy according to the corresponding tracking error signal.

[0040] Specifically, taking the displacement error e(t) obtained at the current time t as an example, a corresponding primary adjustment control signal E(t) is generated through a PI control strategy, and the following conditions are met: ; Wherein, K p is a proportional gain, which determines the reaction strength of the proportional term to the error. K i is an integral gain, which determines the speed of the integral term to accumulate the error.

[0041] The error compensation module includes an inverse function module 51 and a time delay module 52.

[0042] The inverse function module 51 is used to restore the tracking error signal to the error displacement driving signal corresponding to the input of the displacement component. The displacement component is a primary displacement component 1 or a secondary displacement component 2. The signal types of the tracking error signal and the error displacement driving signal are different. Specifically, the primary adjustment control signal, the error displacement driving signal and the historical displacement driving signal are all voltage signals.

[0043] The time delay module 52 is used to obtain the historical displacement driving signal corresponding to the input of the displacement component when the tracking error signal is generated.

[0044] Since the input and output of the system are both displacement signals, the tracking error obtained therefrom is also a displacement signal, and the displacement controller finally outputs a driving signal used to drive the piezoelectric ceramic movement, i.e. a voltage signal. Therefore, the inverse function module 51 needs to be set to convert the error signal into a corresponding voltage signal.

[0045] In this embodiment, the prior art can be used to establish a transfer function model P corresponding to the primary displacement component 1 and the secondary displacement component 2 respectively, to simulate the relationship between the input and output corresponding to the primary displacement component 1 and the secondary displacement component 2 respectively. Then the inverse function model P -1 corresponding to the transfer function model P is obtained.

[0046] In theory, P×P -1 =1, but in the actual construction process, it is impossible to achieve the perfect state in theory, and usually there is a time delay term Z -1 between P and P -d , so the error value in the form of voltage after conversion through the inverse function module 51 also has a certain time delay, i.e. the voltage error may be the error value corresponding to the previous one or several control signals. Therefore, in order to obtain the historical displacement driving signal corresponding to the time of the voltage form error value, the time delay module 52 needs to be set to obtain the corresponding driving signal from the historical control data, so as to ensure the consistency between the error and the driving signal, and avoid the adjustment misalignment problem caused by the misalignment between the error and the driving signal.

[0047] Specifically, the displacement error e(t) obtained at the current time t is also used as an example for explanation. The error displacement driving signal V generated by the inverse function module 51 is e(t) , which only converts the displacement signal into a voltage signal. The delay module 52 obtains the voltage signal with V e(t) The corresponding historical displacement driving signal u(t).

[0048] The first signal addition and subtraction module 55 is used to add the primary adjustment control signal, the error displacement driving signal and the historical displacement driving signal inputted by the corresponding displacement component when generating the tracking error signal, and generate a new displacement driving signal inputted by the corresponding displacement component.

[0049] That is, the new displacement drive signal W=u(t)+V e(t) +E(t).

[0050] Furthermore, the displacement controller also includes a limiting module 56 .

[0051] The amplitude limiting module 56 is in communication with the first signal adding and subtracting module 55 and is configured to limit the amplitude of the new displacement driving signal to a preset amplitude range.

[0052] The amplitude limiting module 56 may be a bandpass filter, which ensures that the new displacement driving signal outputted finally meets the amplitude setting of the corresponding input signal of the corresponding piezoelectric ceramic by setting the corresponding cutoff frequency.

[0053] When the error of the displacement controller converges to near zero (usually tens of milliseconds), the displacement controller actually compensates the V e(t) Specifically, since the error value e(t) gradually decreases to zero, the control signal (K) output by the PI control module 50 is p e(t) tends to zero, tends to a constant value) gradually approaches a constant value. Correspondingly, the control signal output by the error compensation module (i.e. u(t)+V e(t) ) gradually approaches the expected signal.

[0054] like Figure 5As shown, therefore, in the process of gradually reducing the error, the error compensation module gradually learns and approaches the expected control signal based on the current generated displacement error and the historical displacement driving signal, and the adjustment effect of the signal gradually becomes stronger, and since it does not introduce a delay, it ensures that it has higher tracking capability for high-frequency signals in the subsequent process. Correspondingly, since the PI control module 50 generates an adjustment signal based on the error, in this process, the adjustment effect of the signal gradually becomes weaker, to ensure that the error signal can ensure better tracking accuracy at the initial stage, and basically does not play a regulating role at the later stage, avoiding the delay introduced by the integral term. Thus, the error compensation module and the PI module in the system controller of the present application compensate and cooperate with each other, which can avoid the problem that the tracking performance of the system is greatly reduced as the processing time continues, thereby ensuring the processing accuracy of high-frequency periodic signals.

[0055] As a possible embodiment of the present application, the error compensation module further comprises: The second signal addition and subtraction module 53 and the low-pass filter 54.

[0056] The second signal addition and subtraction module 53 is used to superimpose the error displacement driving signal and the historical displacement driving signal to generate a mixed adjustment control signal.

[0057] The low-pass filter 54 is used to remove signals greater than a preset cutoff frequency in the mixed adjustment control signal to generate a primary adjustment control signal.

[0058] Since the primary displacement assembly 1 and the secondary displacement assembly 2 are inevitably disturbed by environmental noise, such as resonance of other components, during actual motion execution, some environmental noise information is inevitably mixed into the actual displacement signal of the displacement assembly in the actual implementation of the present embodiment, so that the e(t) and the Ve(t) generated finally both contain these environmental noise. Since these noises are usually high-frequency noises, the low-pass filter 54 can be set in the error compensation module to remove these environmental noises, thereby improving the accuracy of the signal.

[0059] Correspondingly, the function of the first signal addition and subtraction module 55 in the present embodiment is replaced by: superimposing the primary adjustment control signal and the secondary adjustment control signal to generate a new displacement driving signal input to the corresponding displacement assembly.

[0060] As another possible embodiment of the present application, the control system further comprises a trajectory analysis module, which is used to perform the following steps: S100: performing fast Fourier transform on the tool trajectory to be processed to generate a frequency spectrum corresponding to the tool trajectory to be processed. The frequency spectrum includes all frequency components in the tool trajectory to be processed.

[0061] S200: If there is only one frequency component with an amplitude greater than the preset amplitude threshold and a signal frequency greater than the preset frequency threshold in the spectrum diagram, the displacement signal corresponding to the tool path to be processed is taken as the expected displacement signal input to the fast tool control system.

[0062] The preset amplitude threshold and the preset frequency threshold in the embodiment can be set according to actual use scenarios.

[0063] S300: If there are at least two frequency components with amplitudes greater than the preset amplitude threshold in the spectrum diagram, an alarm signal is generated.

[0064] For a truly single-frequency periodic signal, the peak on the spectrum diagram should be very prominent and concentrated. There is almost no other significant energy distribution around it. Therefore, the preset amplitude threshold can be used to screen whether the tool path to be processed is a single periodic signal. At the same time, the frequency of the signal is determined by the preset frequency threshold. Thus, the trajectory analysis module can determine in advance whether the tool path to be processed is a high-frequency single periodic signal that is more suitable for processing by the system.

[0065] In addition, the above-described diagrams are only schematic illustrations of the processes included in the control system according to the exemplary embodiments of the present application, and are not intended to be limiting. It is readily understood that the processes shown in the above-described diagrams do not indicate or limit the time sequence of these processes. In addition, it is readily understood that these processes can be executed synchronously or asynchronously, for example, in multiple modules.

[0066] It should be noted that, although several modules or units of the device for action execution are mentioned in the above detailed description, such a division is not mandatory. In fact, according to the embodiments of the present 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 into multiple modules or units embodied.

[0067] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto, and any changes or replacements within the technical scope disclosed by the present application can be easily thought of by those skilled in the art, which should be covered within the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the protection scope of the claims.

Claims

1. A dual-stroke fast tool servo control system, applied to a dual-stroke fast tool servo device, wherein the fast tool device comprises a primary displacement component and a secondary displacement component arranged in series in a target displacement direction, wherein the primary displacement component and the secondary displacement component are superimposed to form a total target displacement; characterized in that: The control system includes: Two displacement controllers, each used to generate displacement drive signals for the primary displacement component and the secondary displacement component; the input signal of the displacement controller corresponding to the primary displacement component is a tracking error signal between a desired displacement signal input by the fast tool control system and an 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 and subtraction module; the PI control module and the error compensation module are arranged in parallel, and the first signal addition and subtraction module is communicatively connected to the output ends 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 using a PI control strategy according to the corresponding tracking error signal; The error compensation module includes: an inverse function module and a 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 primary displacement component or a secondary displacement component; the tracking error signal and the error displacement drive signal are of different signal types; The time delay module is used to obtain the historical displacement drive signal inputted by the corresponding displacement component when generating the tracking error signal; The first signal addition and subtraction module 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, and generate a new displacement drive signal input by the corresponding displacement component.

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

3. The control system according to claim 1, characterized in that: The displacement controller further includes: a limiting module; The amplitude limiting module is in communication with the first signal adding and subtracting module, and is used to limit the amplitude of the new displacement driving signal to a preset amplitude range.

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

5. The control system according to claim 1, characterized in that: The control system includes a trajectory analysis module, which is used to perform the following steps: Performing a fast Fourier transform on the tool trajectory to be processed to generate a frequency spectrum corresponding to the tool trajectory to be processed; the frequency spectrum includes all frequency components included in the tool trajectory to be processed; If there is only one frequency component in the spectrum graph whose amplitude is greater than the preset amplitude threshold and whose signal frequency is greater than the preset frequency threshold, the displacement signal corresponding to the tool trajectory to be processed is used as the expected displacement signal input to the fast tool control system.

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

7. The control system according to claim 1, characterized in that: The primary adjustment control signal, the error displacement driving signal and the historical displacement driving signal are all voltage signals.

8. The control system according to claim 1, characterized in that: The first-stage 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 arranged 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 interior of the displacement base is provided with a first driving chamber; The first piezoelectric ceramic is arranged in the first driving chamber, and the two opposite ends of the first piezoelectric ceramic are respectively abutted against the inner wall of the displacement base and the bottom of the first hinge body. 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.

9. The control system according to claim 8, 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 arranged on the side wall of the second hinge body; The second hinge arm is fixedly connected to the first hinge body; a second driving chamber is provided inside the first hinge body; The second piezoelectric ceramic is arranged in the second driving chamber, and the two opposite ends of the second piezoelectric ceramic are respectively abutted against the inner wall of the first hinge body and the bottom of the second hinge body. 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.

10. The control system according to claim 9, characterized in that: The displacement base, the first piezoelectric ceramic, the second piezoelectric ceramic and the first hinge body are all hollow structures; The fast knife device further comprises: 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 inner cavity of the first hinge body; the displacement sensor bracket is a hollow structure; The first displacement sensor is fixedly disposed 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 disposed on the displacement base and is used to obtain displacement information between the first hinge body and the displacement base.

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