A mechanical end jitter suppression method, position loop and drive device
By adding a jitter compensation path in the position loop, a first-order differentiator and vibration harmonic injection unit generate a suppression signal is solved, and the problems of mechanical end jitter and noise suppression are achieved without changing the servo command, which reduces the in-place time without changing the servo command and improve positioning accuracy.
Patent Information
- Application Number
- CN202111672974.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- Filing Date
- 2021-12-31
- Publication Date
- 2024-12-17
- Estimated Expiration
- 2041-12-31
AI Technical Summary
When suppressing mechanical end jitter, the prior art usually leads to command lag and increased in-place time, and cannot take into account the two important servo performance indicators, namely jitter suppression and in-place time.
Add a jitter compensation path in the position loop, generate a suppression signal output through the jitter compensation path, and superimpose it on the output of the control path, adjust the suppression signal according to the jitter and noise conditions at the mechanical end, and realize jitter suppression and noise suppression at the mechanical end. . The method includes a first-order differentializer to acquire a differential signal with position feedback, inject vibrating harmonics into the differential signal, and multiplying it by the jitter suppression to adjust the gain to generate a suppression signal.
Without changing the servo command, it effectively suppresses mechanical end jitter, reduces the time to place, and improves motion positioning accuracy and working efficiency, avoiding command lag.
Smart Images
Figure CN114460838B_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the field of mechanical control, and in particular to a mechanical end jitter suppression method, a position loop and a driving device. Background Art
[0002] In production equipment, load actuators made of light or flexible materials have the advantages of light weight, compact structure, and high safety, and are gradually used in the fields of manufacturing, robotic arms, etc. However, flexible loads contain inherent vibration modes, and during motion positioning, the residual oscillation at the end seriously affects the positioning accuracy and work efficiency.
[0003] To address the problem of mechanical end jitter suppression, the mainstream suppression methods in the industrial control industry are input shaping technology, Damping Filter and command low-pass filtering. These methods can effectively reduce the end jitter of the machine after it is in place, but at the same time, these methods modify the motion command of the user end, causing command lag and increasing the time to reach the destination. Summary of the invention
[0004] In order to solve the above technical problems, the present invention proposes a mechanical end jitter suppression method, a position loop and a drive device to solve the problem that the two important servo performance indicators of in-position jitter and in-position time cannot be taken into account at the same time.
[0005] A first aspect of the present invention discloses a method for suppressing mechanical end jitter, comprising:
[0006] A jitter compensation path is added to the position loop, and a jitter suppression signal output is generated through the jitter compensation path;
[0007] The suppression signal output of the jitter compensation path is superimposed on the output of the control path of the position loop to form a position loop output signal; wherein the output of the control path is obtained in the following manner: in the control path of the position loop, the position deviation is obtained by subtracting the feedback position from the command position, and the position deviation is multiplied by the position loop gain to obtain the output of the control path;
[0008] The suppression signal output of the jitter compensation path is adjusted according to the jitter and noise conditions of the mechanical end, so as to achieve jitter suppression and noise suppression of the mechanical end.
[0009] According to the method of the first aspect of the present invention, the jitter suppression signal output generated by the jitter compensation path includes: obtaining a differential signal of position feedback through a first-order differentiator; injecting vibration harmonics into the obtained differential signal according to the angular frequency of the mechanical end jitter to obtain a jitter suppression signal; and multiplying the obtained jitter suppression signal by a jitter suppression adjustment gain to obtain an output of the jitter compensation path.
[0010] According to the method of the first aspect of the present invention, the transfer function of the first-order differentiator is: The transfer function of the vibration harmonics is: Among them, parameter s is the complex frequency of Laplace transform, parameter K is the bandwidth angular frequency of the first-order differentiator, and parameter w is the angular frequency of mechanical end jitter.
[0011] According to the method of the first aspect of the present invention, adjusting the suppression signal output of the jitter compensation path according to the jitter and noise conditions of the mechanical end includes:
[0012] Parameter setting: obtaining the mechanical end jitter angular frequency value of the position loop, the initial value of the position loop gain, the initial value of the jitter suppression adjustment gain, and the initial value of the bandwidth angular frequency of the first-order differentiator;
[0013] Run the equipment and observe whether the mechanical end shakes. If the mechanical end shakes, increase the value of the jitter suppression adjustment gain. If the mechanical end does not shake, observe whether the noise is large. If the noise is large, reduce the value of the bandwidth angular frequency of the first-order differentiator. If the noise meets the preset requirements, end the adjustment.
[0014] According to the method of the first aspect of the present invention, the parameter setting includes: obtaining the angular frequency value of the mechanical end jitter through a measuring device; setting the initial value of the position loop gain; setting the initial value of the jitter suppression adjustment gain to twice the angular frequency value of the mechanical end jitter; and setting the initial value of the bandwidth angular frequency of the first-order differentiator to the value of the position loop gain.
[0015] The second aspect of the present invention discloses a position loop, including a control path and a jitter compensation path; the control path is used to obtain a position deviation by subtracting a feedback position from a command position, and then multiplying the position deviation by a position loop gain to obtain an output of the control path; the jitter compensation path is used to generate a suppression signal output for suppressing jitter, and adjust the suppression signal output according to the jitter and noise conditions of the mechanical end, thereby achieving jitter suppression and noise suppression at the mechanical end.
[0016] According to the position loop of the second aspect of the present invention, the jitter compensation path includes: a first-order differentiator, used to obtain a differential signal of position feedback; a harmonic injection unit, used to inject vibration harmonics into the obtained differential signal to obtain a jitter-suppressed signal; and a jitter suppression adjustment gain unit, used to multiply the obtained jitter-suppressed signal by a jitter suppression adjustment gain to obtain an output of the jitter compensation path.
[0017] According to the position loop of the second aspect of the present invention, the jitter suppression adjustment gain unit is also used to increase the value of the jitter suppression adjustment gain when mechanical end jitter occurs; the first-order differentiator is also used to reduce its own angular frequency value when the noise is observed to be greater than the preset requirement.
[0018] A third aspect of the present invention discloses a driving device, comprising the position ring described in any one of the above items.
[0019] A fourth aspect of the present invention discloses a computer-readable storage medium, on which a computer program is stored. When the computer program is executed by a processor, the steps in any of the above-mentioned methods for suppressing mechanical end jitter are implemented.
[0020] The mechanical end jitter suppression scheme proposed by the present invention adds a jitter compensation path to the position loop, generates a jitter suppression signal output through the jitter compensation path, and superimposes the signal on the output of the control path of the position loop as the position loop output signal. Then, the suppression signal output of the jitter compensation path is adjusted according to the jitter and noise conditions of the mechanical end, so as to achieve jitter suppression and noise suppression of the mechanical end, thereby solving the jitter problem of the mechanical end after the servo is in place without changing the servo command. Compared with the prior art in the background technology, the mechanical end jitter suppression method of the present invention does not cause command lag and can also reduce the time to reach the position. BRIEF DESCRIPTION OF THE DRAWINGS
[0021] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.
[0022] Figure 1 is a flow chart of a method for suppressing mechanical end jitter according to an embodiment of the present invention;
[0023] Figure 2 is a schematic diagram of a position loop including a control path and a jitter compensation path according to an embodiment of the present invention;
[0024] Figure 3 The flowchart is a method for adjusting a mechanical end jitter suppression algorithm implemented in a servo position loop according to an embodiment of the present invention. DETAILED DESCRIPTION
[0025] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.
[0026] This embodiment provides a method for suppressing mechanical end jitter. Figure 1 As shown, the method includes:
[0027] 101. Add a jitter compensation path in the position loop, and generate a jitter suppression signal output through the jitter compensation path;
[0028] 102. Superimpose the suppression signal output of the jitter compensation path on the output of the control path of the position loop to form a position loop output signal; wherein the output of the control path is obtained by: in the control path of the position loop, the position deviation is obtained by subtracting the feedback position from the command position, and the position deviation is multiplied by the position loop gain to obtain the output of the control path;
[0029] 103. According to the jitter and noise conditions of the mechanical end, the suppression signal output of the jitter compensation path is adjusted to achieve jitter suppression and noise suppression of the mechanical end.
[0030] The method of this embodiment can be applied to a position closed-loop servo system, which is composed of a servo motor, a comparison circuit, a servo amplifier circuit, a speed detector, and a position detector installed on a workbench. This system automatically detects the actual displacement of the workbench and compares it with the command value, and uses the difference to perform control.
[0031] The method of this embodiment can also be applied to other motion servo systems including a position loop, such as a common three-loop control system, which includes a current loop, a speed loop, and a position loop from the inside to the outside.
[0032] The mechanical end jitter suppression method of this embodiment adds a jitter compensation path to the position loop, generates a jitter suppression signal output through the jitter compensation path, and superimposes the signal on the output of the original control path of the position loop as the position loop output signal, and then adjusts the suppression signal output of the jitter compensation path according to the jitter and noise conditions of the mechanical end to achieve jitter suppression and noise suppression of the mechanical end, thereby solving the jitter problem of the mechanical end after the servo is in place without changing the servo command. The mechanical end jitter suppression method of the present invention does not cause command lag and can also reduce the time to reach the position.
[0033] In some embodiments, generating a jitter suppression signal output through a jitter compensation path specifically includes: obtaining a differential signal of position feedback through a first-order differentiator; injecting vibration harmonics into the obtained differential signal according to the angular frequency of the mechanical end jitter to obtain a jitter suppression signal; and multiplying the obtained jitter suppression signal by a jitter suppression adjustment gain to obtain an output of the jitter compensation path. The vibration harmonics are generated based on the measured jitter of the mechanical end, specifically based on the ability to compensate for the jitter of the mechanical end.
[0034] Figure 2 As shown, a position loop including a control path and a jitter compensation path provided by the present embodiment, in which parameter Kp is the control gain of the servo position loop, parameter K is the bandwidth angular frequency of the first-order differentiator, parameter w is the angular frequency of the mechanical end vibration, s is the Laplace transform complex frequency, and parameter Gain is the adjustment gain of jitter suppression.
[0035] Figure 2 The position loop in has two paths, namely the control path and the jitter compensation path. The open-loop transfer function of the control path is shown as follows: g(s) = Kp. The control path first subtracts the position feedback from the position command to obtain the position deviation, and then multiplies it by the position loop gain Kp to obtain the output of the control loop.
[0036] The jitter compensation path includes three links: the first-order differentiator, the harmonic injection link, and the jitter suppression adjustment gain. The first-order differentiator is used to obtain a low-noise differential signal, the harmonic injection link is used to inject vibration harmonics, and the jitter suppression adjustment gain is used to adjust the vibration damping.
[0037] First, the differential signal of position feedback is obtained through a first-order differentiator. The transfer function of the first-order differentiator is shown as follows:
[0038] The differential signal of position feedback is injected into the vibration harmonic to obtain a signal that suppresses vibration. The vibration harmonic transfer function is shown in the following formula:
[0039] Finally, multiply by the jitter suppression adjustment gain to get the output of the jitter compensation path. The output of the position loop is the speed loop command, which is equal to the output of the control path plus the output of the jitter compensation path.
[0040] In some embodiments, Figure 3 As shown, the step of adjusting the suppression signal output of the jitter compensation path according to the jitter and noise conditions of the mechanical end includes:
[0041] Parameter setting: Get the mechanical end jitter angular frequency value of the position loop, the initial value of the position loop gain, the initial value of the jitter suppression adjustment gain, and the initial value of the bandwidth angular frequency of the first-order differentiator;
[0042] Run the equipment and observe whether the mechanical end is shaking. If the mechanical end is shaking, increase the value of the jitter suppression adjustment gain. If the mechanical end is not shaking, observe whether the noise is large. If the noise is large, reduce the value of the bandwidth angular frequency of the first-order differentiator. If the noise meets the preset requirements, end the adjustment.
[0043] The above-mentioned parameter settings include: obtaining the angular frequency value of the mechanical end jitter through a measuring device; setting the initial value of the position loop gain; setting the initial value of the jitter suppression adjustment gain to twice the angular frequency value of the mechanical end jitter; and setting the initial value of the bandwidth angular frequency of the first-order differentiator to the value of the position loop gain.
[0044] The adjustment method of the terminal jitter suppression algorithm of this embodiment is to first configure the parameters of the position loop, including the mechanical terminal jitter angular frequency value, the position loop gain value, the jitter suppression gain value and the bandwidth angular frequency of the first-order differentiator. The angular frequency value of the mechanical terminal jitter can be obtained through an external measurement device (the external measurement device is not within the scope of patent protection), the position loop gain is set by default to, for example, 40, the jitter suppression gain value is set by default to 2 times the mechanical terminal jitter angular frequency value, and the bandwidth angular frequency of the first-order differentiator is set by default to the gain value of the position loop. Then run to observe whether the mechanical terminal is jittering. If the mechanical terminal is jittering, increase the gain value of jitter suppression. If no terminal jitter occurs, observe whether the noise is large. If the noise is large, reduce the angular frequency value of the first-order differentiator. If the noise meets the conditions, end the adjustment.
[0045] The terminal jitter suppression method of this embodiment provides an algorithm structure for realizing mechanical terminal jitter suppression in a servo position loop, realizing mechanical in-position jitter suppression without the lag effect of command filtering, and reducing the mechanical movement in-position time; it also provides an adjustment method for realizing the mechanical terminal jitter suppression algorithm in a servo position loop, which can optimize the performance of in-position jitter, in-position time and noise intensity in applications.
[0046] An embodiment of the present invention also provides a position loop, including a control path and a jitter compensation path; the control path is used to obtain a position deviation by subtracting a feedback position from a command position, and then multiplying the position deviation by a position loop gain to obtain an output of the control path; the jitter compensation path is used to generate a suppression signal output for suppressing jitter, and adjust the suppression signal output according to the jitter and noise conditions of the mechanical end, thereby achieving jitter suppression and noise suppression at the mechanical end.
[0047] According to the position loop of this embodiment, the jitter compensation path includes: a first-order differentiator, used to obtain a differential signal of position feedback; a harmonic injection unit, used to inject vibration harmonics into the obtained differential signal to obtain a jitter-suppressed signal; and a jitter suppression adjustment gain unit, used to multiply the obtained jitter-suppressed signal by a jitter suppression adjustment gain to obtain an output of the jitter compensation path.
[0048] According to the position loop of an embodiment of the present invention, the jitter suppression adjustment gain unit is also used to increase the value of the jitter suppression adjustment gain when mechanical end jitter occurs; the first-order differentiator is also used to reduce its own angular frequency value when the noise is observed to be greater than the preset requirement.
[0049] An embodiment of the present invention further provides a driving device, comprising the position ring described in any one of the above items.
[0050] An embodiment of the present invention further provides a computer-readable storage medium, on which a computer program is stored. When the computer program is executed by a processor, the steps in any one of the above-mentioned methods for suppressing mechanical end jitter are implemented.
[0051] The mechanical end jitter suppression scheme proposed by the present invention adds a jitter compensation path to the position loop, generates a jitter suppression signal output through the jitter compensation path, and superimposes the signal on the output of the control path of the position loop as the position loop output signal. Then, the suppression signal output of the jitter compensation path is adjusted according to the jitter and noise conditions of the mechanical end, so as to achieve jitter suppression and noise suppression of the mechanical end, thereby solving the jitter problem of the mechanical end after the servo is in place without changing the servo command. Compared with the prior art in the background technology, the mechanical end jitter suppression method of the present invention does not cause command lag and can also reduce the time to reach the position.
[0052] The mechanical end jitter suppression scheme proposed in the present invention can effectively suppress the mechanical end jitter after the servo is in place without changing the servo command; the mechanical end jitter suppression algorithm of the present invention will not cause command lag and reduce the time to reach the position.
[0053] Please note that the technical features of the above embodiments can be combined arbitrarily. In order to make the description concise, all possible combinations of the technical features in the above embodiments are not described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification. The above embodiments only express several implementation methods of the present application, and their descriptions are relatively specific and detailed, but they cannot be understood as limiting the scope of the invention patent. It should be pointed out that for ordinary technicians in this field, without departing from the concept of the present application, several variations and improvements can be made, which all belong to the scope of protection of the present application. Therefore, the scope of protection of the patent in this application shall be based on the attached claims.
Claims
1. A method for suppressing mechanical end jitter, characterized in that: include: A jitter compensation path is added to the position loop, and a jitter suppression signal output is generated through the jitter compensation path; The suppression signal output of the jitter compensation path is superimposed on the output of the control path of the position loop to form a position loop output signal; wherein the output of the control path is obtained in the following manner: in the control path of the position loop, the position deviation is obtained by subtracting the feedback position from the command position, and the position deviation is multiplied by the position loop gain to obtain the output of the control path; According to the jitter and noise conditions of the mechanical end, the suppression signal output of the jitter compensation path is adjusted to achieve jitter suppression and noise suppression of the mechanical end. The jitter compensation path generates a suppression signal output for suppressing jitter, including: The differential signal of the feedback position is obtained through a first-order differentiator; Injecting vibration harmonics into the obtained differential signal according to the angular frequency of the mechanical end jitter to obtain a jitter-suppressing signal; Multiplying the obtained jitter suppression signal by the jitter suppression adjustment gain to obtain an output of the jitter compensation path; The transfer function of the first-order differentiator is: The transfer function of the vibration harmonics is: in, Parameter s is the complex frequency of Laplace transform, parameter k is the bandwidth angular frequency of the first-order differentiator, and parameter w is the angular frequency of mechanical end jitter.
2. The method for suppressing mechanical end jitter according to claim 1, characterized in that: The step of adjusting the suppression signal output of the jitter compensation path according to the jitter and noise conditions of the mechanical end includes: Parameter setting: obtaining the mechanical end jitter angular frequency value of the position loop, the initial value of the position loop gain, the initial value of the jitter suppression adjustment gain, and the initial value of the bandwidth angular frequency of the first-order differentiator; Run the equipment and observe whether the mechanical end shakes. If the mechanical end shakes, increase the value of the jitter suppression adjustment gain. If the mechanical end does not shake, observe whether the noise is large. If the noise is large, reduce the value of the bandwidth angular frequency of the first-order differentiator. If the noise meets the preset requirements, end the adjustment.
3. The method for suppressing mechanical end jitter according to claim 2, characterized in that: The parameter settings include: Obtain the angular frequency value of the mechanical end jitter by measuring the device; Setting the initial value of the position loop gain; The initial value of the jitter suppression adjustment gain is set to twice the angular frequency value of the mechanical end jitter; The initial value of the bandwidth angular frequency of the first-order differentiator is set to the value of the position loop gain.
4. A position ring, characterized in that: Including control path and jitter compensation path; The control path is used to obtain a position deviation by subtracting a feedback position from a command position, and then multiplying the position deviation by a position loop gain to obtain an output of the control path; The jitter compensation path is used to generate a suppression signal output for suppressing jitter based on the feedback position and the jitter of the mechanical end, and adjust the suppression signal output according to the jitter and noise of the mechanical end, and superimpose the suppression signal output on the output of the control path to form a position loop output signal, thereby realizing jitter suppression and noise suppression of the mechanical end; Wherein, the jitter compensation path includes: A first-order differentiator, used to obtain a differential signal of the feedback position; A harmonic injection unit, used for injecting vibration harmonics into the obtained differential signal to obtain a jitter-suppressed signal; A jitter suppression gain adjustment unit, used for multiplying the obtained jitter suppression signal by the jitter suppression gain to obtain an output of the jitter compensation path; The transfer function of the first-order differentiator is: The transfer function of the vibration harmonics is: in, Parameter s is the complex frequency of Laplace transform, parameter k is the bandwidth angular frequency of the first-order differentiator, and parameter w is the angular frequency of mechanical end jitter.
5. The position ring according to claim 4, characterized in that: The jitter suppression adjustment gain unit is also used to increase the value of the jitter suppression adjustment gain when the mechanical end jitter occurs; the first-order differentiator is also used to reduce its own angular frequency value when the noise is observed to be greater than the preset requirement.
6. A driving device, characterized in that: Comprising the position ring as claimed in claim 4 or 5.
7. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the steps in the method for suppressing mechanical end jitter according to any one of claims 1 to 3 are implemented.