Kinetic parameter rapid identification method

Abstract

The invention discloses a method for rapidly identifying kinetic parameters. The method comprises the following steps: S1, establishing a multi-body system kinetic model of an ultra-precise fly-cutting machine tool; s2, determining a transfer matrix and a transfer equation of the elements; s3, using a method of a kinetic model topological graph to obtain a transfer relationship between element state vectors in the multi-body system kinetic model; s4, assembling a total transfer matrix of the system according to the transfer matrixes of the elements, and determining a total transfer equation of the system; s5, determining a characteristic equation of the system and inherent frequencies of all orders of the system according to the total transfer equation and the boundary conditions of the precise fly-cutting machine tool system; s6, obtaining a characteristic vector and a vibration characteristic of the system according to the element transfer equation; and S7, combining a multi-body system transfer matrix method with an optimized genetic algorithm to realize high-precision identification of the kinetic parameters of the machine tool system.

Description

Technical Field

[0001] The invention belongs to the technical field of dynamics simulation, and in particular relates to a method for fast identification of dynamics parameters. Background Art

[0002] With the further development of ultra-precision manufacturing, people have higher and higher requirements for extreme manufacturing quality. Ultra-precision diamond flycutting technology continues to develop and become an important means to ensure the realization of complex surface structure processing and ultra-precision processing. In the ultra-precision flycutting process, the vibration between the tool and the workpiece caused by the combined effects of spindle system vibration, foundation vibration, air source pressure fluctuation, guide rail oil pressure fluctuation and cutting force fluctuation is a key factor affecting the quality of the processed surface. Existing research mainly focuses on the dynamic characteristics of ultra-precision flycutting machines and their influence on the processed surface shape, aiming to clarify the mapping relationship between the key dynamic parameters of the process system of ultra-precision flycutting machines and the processing surface quality, especially the medium-frequency waviness error, so as to provide a theoretical basis for predicting and optimizing key dynamic parameters and improving extreme manufacturing quality. Summary of the invention

[0003] The purpose of the present invention is to solve the above problems and provide a method for quickly identifying dynamic parameters based on the multi-body system transfer matrix method and genetic algorithm, with the goal of achieving accurate control of the machining surface of an ultra-precision fly-cutting machine.

[0004] In order to solve the above technical problems, the technical solution of the present invention is: a method for rapid identification of kinetic parameters, comprising the following steps:

[0005] S1. Establish a multi-body system dynamics model of ultra-precision fly cutting machine tools;

[0006] S2. Based on the typical multi-body system dynamics model of ultra-precision machine tool system, the multi-body system transfer matrix method is applied to establish the transfer matrix and transfer equation of the components;

[0007] S3, using the method of dynamic model topology diagram to graphically describe the relationship between the state vectors of the body elements and the hinge elements in the multi-body system dynamics model, the position sequence number, the boundary sequence number, and the transfer direction, and obtain the transfer relationship between the state vectors of each element in the multi-body system dynamics model;

[0008] S4, assembling the total transfer matrix of the system according to the transfer matrices of the components, and determining the total transfer equation of the system;

[0009] S5. Determine the characteristic equation of the system and the natural frequencies of each order of the system according to the total transfer equation and boundary conditions of the precision fly-cutting machine tool system;

[0010] S6. Obtain the characteristic vector and vibration characteristics of the system according to the component transfer equation;

[0011] S7. Combine the multi-body system transfer matrix method with the optimization genetic algorithm to achieve high-precision identification of the dynamic parameters of the machine tool system.

[0012] Furthermore, in step S1, the method for establishing the multi-body system dynamics model of the ultra-precision fly-cutting machine tool is as follows:

[0013] S11. According to the connection mode and mutual motion relationship between the parts of the ultra-precision fly-cutting machine tool process system, its components are divided into 17 subsystems, each subsystem is regarded as a body element, and the body elements are connected by hinge elements. The numbers of the body elements and hinge elements are uniformly labeled;

[0014] S12. According to the connection relationship between the subsystems, the multi-body system dynamics model of the ultra-precision fly-cutting machine tool is obtained.

[0015] Furthermore, in step S2, according to a typical multi-body system dynamics model of an ultra-precision machine tool system, a multi-body system transfer matrix method is applied to establish the transfer matrix and transfer equation of the element as follows:

[0016] S21. Establish the multi-body system dynamics equations of a typical ultra-precision machine tool system, including the transfer matrix of a spatial vibrating rigid body, the transfer matrix of a spatial vibrating beam, the transfer matrix of a spatial elastic hinge, the transfer matrix of a rotating spindle, the spindle air film stiffness, the stiffness of bolted joints, and the transfer matrix of a flexible body of arbitrary shape in space;

[0017] S22. Select the corresponding matrix according to the component type, process the components as single-end input single-end output or multi-end input single-end output components, and obtain the transfer matrix and transfer equation of the components:

[0018]

[0019] Where i is the component number (all components are numbered consecutively starting from 1), r is the input point number of component i (the input points of component i are numbered consecutively starting from 1), and Z i,O and are the state vectors of the output point of element i and the rth input point, respectively. The input point I r The corresponding transfer matrix, N is the number of input points of element i; R T is the modal coordinate corresponding to the linear displacement of the input point or output point relative to its equilibrium position, Θ T is the modal coordinate corresponding to the angular displacement of the input point or output point relative to its equilibrium position, M T is the modal coordinate corresponding to the internal moment at the input point or output point.

[0020] Furthermore, in step S4, the method of assembling the total transfer matrix and the total transfer equation of the system according to the transfer matrices of the components is as follows:

[0021] S41. According to the relationship between the system boundary state vectors, the system total transfer equation is obtained:

[0022] U all Z all =0 (3)

[0023] Among them, U all is the total transfer matrix of the system, Z all is the system boundary state vector, which is an array composed of the boundary state vectors arranged in order;

[0024] S42. Based on the multi-body system dynamics model of the ultra-precision machine tool system, the total transfer matrix U of the ultra-precision fly-cutting machine tool process system is obtained by applying the automatic derivation principle of the total transfer equation of the machine tool system. all :

[0025]

[0026] in,

[0027]

[0028]

[0029] in,

[0030] S43. Determine the system boundary state vector:

[0031]

[0032] S44. Determine the system boundary conditions:

[0033]

[0034] The total transfer equation of the system after substituting the boundary conditions is obtained:

[0035]

[0036] in, is an array of unknown boundary state variables of the system, is the square matrix obtained by deleting the columns corresponding to the zero elements of the system boundary state vector from the total transfer matrix.

[0037] Furthermore, in step S5, the method for determining the characteristic equation of the system and the natural frequency of the system according to the total transfer equation and boundary conditions of the precision fly-cutting machine tool system is as follows:

[0038] S51. Based on the total transfer equation and boundary conditions of the precision fly-cutting machine tool system, the characteristic equation of the system is obtained:

[0039]

[0040] S52, use the bisection method, parabola method, chord intercept method, golden section method and recursive search method to solve the equation and obtain the natural frequency ω of each order of the system k (k=1,2,…).

[0041] Furthermore, in step S6, the method for obtaining the characteristic vector and vibration characteristics of the system according to the component transfer equation is as follows:

[0042] S61. Substituting the natural frequencies of each order of the system into the total transfer equation of the ultra-precision fly-cutting machine tool process system, a homogeneous linear equation group about the unknown boundary state variables of the system is obtained;

[0043] S62. Based on the singular value decomposition technology, the total transfer equation of the ultra-precision fly-cutting machine tool process system is solved to obtain a homogeneous linear equation group about the unknown boundary state variables of the system, and its L linearly independent non-zero solutions are obtained:

[0044]

[0045] Multiply both sides by the matrix N to obtain L sets of non-zero solutions of the unknown boundary state vector of the system; where N is the orthogonal matrix used for singular value decomposition;

[0046] S63. After the characteristic vectors of each boundary of the system are obtained, the characteristic vectors of each connection point are recursively calculated from the input boundary to the output boundary of the system according to the transfer equations of each component, and the displacement of the corresponding point of the body component is extracted to obtain the vibration characteristics of the system.

[0047] Furthermore, in step S7, the method of combining the multi-body system transfer matrix method with the optimized genetic algorithm to achieve high-precision identification of the dynamic parameters of the machine tool system is as follows:

[0048] S71, minimizing the difference between the modal parameters obtained by simulation and the test as the objective function, and establishing a fitness function;

[0049] S72, through genetic algorithm selection, crossover, mutation and other operator search optimization;

[0050] S73. Find the minimum value of the objective function.

[0051] The beneficial effects of the present invention are as follows: the present invention provides a method for rapid identification of dynamic parameters, establishes a rapid dynamic simulation system for multi-body systems of ultra-precision fly-cutting machine tools, and realizes rapid dynamic identification of the process system of ultra-precision fly-cutting machine tools. BRIEF DESCRIPTION OF THE DRAWINGS

[0052] Figure 1 It is a flow chart of a method for rapid identification of kinetic parameters of the present invention;

[0053] Figure 2 It is a dynamic model diagram of the process system of the ultra-precision fly-cutting machine tool of the present invention;

[0054] Figure 3 It is a topological diagram of the dynamics model of the process system of the ultra-precision fly-cutting machine tool of the present invention;

[0055] Figure 4 It is a topological diagram of the dynamics model of the derived tree system of the ultra-precision fly-cutting machine tool of the present invention;

[0056] Figure 5 The flow chart of the physical identification method based on the multi-body system transfer matrix method and optimized genetic algorithm of the present invention;

[0057] Explanation of the reference numerals in the accompanying drawings: 0, earth; 4, upper left guide rail; 7, upper right guide rail; 9, slide; 11, left guide rail; 13, right guide rail; 15, air-floating spindle I; 18, virtual rigid body; 20, air-floating spindle II; 23, motor rotor; 25, bearing core shaft; 29, front tool holder; 31, rear tool holder; 33, tool disc; 35, thrust spindle; 37, crossbeam; 39, left column; 41, right column; 43, bed; 45, foundation. DETAILED DESCRIPTION

[0058] The present invention will be further described below in conjunction with the accompanying drawings and specific embodiments:

[0059] like Figures 1 to 5 As shown, the present invention provides a method for rapid identification of kinetic parameters, comprising the following steps:

[0060] S1. Establish a multi-body system dynamics model of ultra-precision fly cutting machine tools.

[0061] In step S1, the method for establishing the multi-body system dynamics model of the ultra-precision fly cutting machine tool is as follows:

[0062] S11. According to the connection mode and mutual movement relationship between the parts of the ultra-precision fly-cutting machine tool process system, its composition is divided into 17 subsystems. Each subsystem is regarded as a body element. The body elements are connected by hinge elements. The body elements and hinge elements are numbered uniformly.

[0063] S12. According to the connection relationship between the subsystems, the multi-body system dynamics model of the ultra-precision fly-cutting machine tool is obtained.

[0064] The dynamic model of the process system of ultra-precision fly cutting machine tool is as follows Figure 2 As shown, the mechanical model includes a crossbeam 37, a column, a bed 43 and a foundation 45 arranged from top to bottom, and the columns include a left column 39 and a right column 41. The tops of the left column 39 and the right column 41 are connected to the bottom of the crossbeam 37, and the bottoms of the left column 39 and the right column 41 are connected to the bed 43. The bottom of the bed 43 is provided with a support foot, and the support foot is connected to the foundation through 45. A slide 9 is provided between the left column 39 and the right column 41, and the bottom of the slide 9 is provided with a left upper rail 4, a left side rail 11, a right upper rail 7 and a right side rail 13, respectively. The left upper rail 4 is located on the left side rail 11, the right upper rail 7 is located on the right side rail 13, and the left side rail 11 and the right side rail 13 are both located on the bed 43.

[0065] A cutter disc 33 is provided at the bottom of the crossbeam 37, and the cutter disc 33 is located on the upper part of the slide 9. The end face of the cutter disc 33 is provided with a thrust spindle 35, a virtual rigid body 18, an air-floating spindle I 15, an air-floating spindle II 20, a bearing core shaft 25 and a motor rotor 23 in sequence. The air-floating spindle I 15 and the air-floating spindle II 20 are connected as a whole to form a spindle, and are divided into two sections of beam elements for analysis in the dynamic model. A crossbeam through hole is provided on the crossbeam 37, and the thrust spindle 35, the virtual rigid body 18, the air-floating spindles 15, 20, the bearing core shaft 25 and the motor rotor 23 are passed through the crossbeam through hole. A front tool holder 29 and a rear tool holder 31 are provided on the side of the cutter disc 33. The front tool holder 29 and the rear tool holder 31 are used to connect the cutter disc 3 and the crossbeam 37, thereby fixing the cutter disc 33. The parts that have a positional movement relationship in the model are all installed with elastic hinges to form an elastic hinge connection, such as Figure 2As shown in the figure, the balls pointed to by numbers 1, 2, 3, 5, 6, 8, 10, 12, 14, 19, 21, 22, 24, 26, 27, 28, 30, 32, 36, 38, 40, 42, 44 and 46 are all elastic hinges, and their numbers are the numbers of the elastic hinges. The balls pointed to by 16, 17 and 34 are the fixed hinges, and 16, 17 and 34 are the numbers of the fixed hinges. In this embodiment, the fixed hinges and the elastic hinges are all existing hinge devices. In this embodiment, specifically: the foundation 45 is connected to the ground 0 by an elastic hinge numbered 46; the upper surface of the foundation 45 is connected to the lower surface of the bed 43 by an elastic hinge numbered 44; the upper surface of the bed 43 is connected to the left guide rail 11, the right guide rail 13, the left column 39, the left column 41 and the lower surface of the slider 9 by five elastic hinges numbered 12, 14, 40, 42, and 10. The upper surface of the slider 9 is connected to the lower surface of the left upper guide rail 4 and the lower surface of the right upper guide rail 7 by two elastic hinges numbered 5 and 8 respectively; the left surface of the slider 9 is connected to the right surface of the left lower guide rail 11 by an elastic hinge numbered 1, and the right surface of the slider 9 is connected to the left surface of the right guide rail 13 by an elastic hinge numbered 2. The upper surface of the left guide rail 11 is connected to the lower surface of the left upper guide rail 4 by an elastic hinge numbered 3. The upper surface of the right guide rail 13 is connected to the lower surface of the right upper guide rail 7 by an elastic hinge numbered 6. The contact parts of the side surface of the cutter disc 33 and the side surface of the front tool holder 29 and the rear tool holder 31 are connected by two elastic hinges numbered 32 and 30 respectively; the upper surface of the cutter disc 33 is connected to the lower surface of the thrust spindle 35 by a fixed hinge numbered 34. The upper surface of the thrust spindle 35 is connected to the lower surface of the air-floating spindle 15 by an elastic hinge numbered 28. The air-floating spindle is divided into two sections of beams, and the air-floating spindle I15 and the air-floating spindle II20 are connected by fixed hinges numbered 16 and 17 and virtual rigid body 18 respectively. The upper surface of the air-floating spindle 20 and the lower surface of the bearing core shaft 25 are connected by an elastic hinge numbered 21. The upper surface of the bearing core shaft 25 and the lower surface of the motor rotor 23 are connected by an elastic hinge numbered 24. The crossbeam 37 is connected to the left column 39, the right column 41, the thrust spindle 35, the virtual rigid body 18, the bearing core shaft 25, and the motor rotor 23 through elastic hinges numbered 38, 27, 36, 19, 26, and 22 respectively.

[0066] S2. Based on the typical multi-body system dynamics model of ultra-precision machine tool system, the multi-body system transfer matrix method is applied to establish the transfer matrix and transfer equation of the components.

[0067] In step S2, according to the typical multi-body system dynamics model of ultra-precision machine tool system, the multi-body system transfer matrix method is applied to establish the transfer matrix and transfer equation of the components as follows:

[0068] S21. Establish the multi-body system dynamics equations of a typical ultra-precision machine tool system, including the transfer matrix of the spatial vibrating rigid body, the transfer matrix of the spatial vibrating beam, the transfer matrix of the spatial elastic hinge, the transfer matrix of the rotating spindle, the spindle air film stiffness, the bolt joint stiffness and the transfer matrix of the flexible body of arbitrary shape in space.

[0069] S22. Select the corresponding matrix according to the component type, process the components as single-end input single-end output or multi-end input single-end output components, and obtain the transfer matrix and transfer equation of the components:

[0070]

[0071] Where i is the component number (all components are numbered consecutively starting from 1), r is the input point number of component i (the input points of component i are numbered consecutively starting from 1), and Z i,O and are the state vectors of the output point of element i and the rth input point, respectively. The input point I r The corresponding transfer matrix, N is the number of input points of element i; R T is the modal coordinate corresponding to the linear displacement of the input point or output point relative to its equilibrium position, Θ T is the modal coordinate corresponding to the angular displacement of the input point or output point relative to its equilibrium position, M T is the modal coordinate corresponding to the internal moment at the input point or output point.

[0072] S3. Use the method of dynamic model topology diagram to graphically describe the relationship between the state vectors of body elements and hinge elements in the multi-body system dynamics model, position sequence number, boundary sequence number, and transfer direction, and obtain the transfer relationship between the state vectors of each element in the multi-body system dynamics model.

[0073] The topological diagram of the dynamic model of the process system of the ultra-precision fly-cutting machine tool of the present invention is as follows: Figure 3 As shown in the figure, the closed loop of the topological diagram of the dynamic model of the ultra-precision fly-cutting machine tool is cut off to obtain its derived tree system topological diagram, which helps to intuitively describe the transfer relationship and transfer direction between the state vectors of each component. The topological diagram of the dynamic model of the derived tree system of the ultra-precision fly-cutting machine tool is shown in the figure. Figure 4 shown.

[0074] S4. Assemble the total transfer matrix of the system according to the transfer matrices of the components and determine the total transfer equation of the system.

[0075] In step S4, the method of assembling the total transfer matrix and the total transfer equation of the system according to the transfer matrices of the components is as follows:

[0076] S41. According to the relationship between the system boundary state vectors, the system total transfer equation is obtained:

[0077] U all Z all =0 (3)

[0078] Among them, U all is the total transfer matrix of the system, Z all is the system boundary state vector, which is an array composed of the boundary state vectors arranged in order.

[0079] S42. Based on the multi-body system dynamics model of the ultra-precision machine tool system, the total transfer matrix U of the ultra-precision fly-cutting machine tool process system is obtained by applying the automatic derivation principle of the total transfer equation of the machine tool system. all .

[0080]

[0081] in,

[0082]

[0083]

[0084] in,

[0085] S43. Determine the system boundary state vector:

[0086]

[0087] S44. Determine the system boundary conditions:

[0088]

[0089] The total transfer equation of the system after substituting the boundary conditions is obtained:

[0090]

[0091] in, is an array of unknown boundary state variables of the system, is the square matrix obtained by deleting the columns corresponding to the zero elements of the system boundary state vector from the total transfer matrix.

[0092] S5. Determine the characteristic equation of the system and the natural frequencies of each order of the system based on the total transfer equation and boundary conditions of the precision fly-cutting machine tool system.

[0093] In step S5, the method for determining the characteristic equation of the system and the natural frequency of the system according to the total transfer equation and boundary conditions of the precision fly-cutting machine tool system is as follows:

[0094] S51. Based on the total transfer equation and boundary conditions of the precision fly-cutting machine tool system, the characteristic equation of the system is obtained:

[0095]

[0096] S52, use the bisection method, parabola method, chord intercept method, golden section method and recursive search method to solve the equation and obtain the natural frequency ω of each order of the system k (k=1,2,…).

[0097] S6. Obtain the system's characteristic vector and vibration characteristics based on the component transfer equation.

[0098] In step S6, the method of obtaining the characteristic vector and vibration characteristics of the system according to the component transfer equation is as follows:

[0099] S61. Substituting the natural frequencies of each order of the system into the total transfer equation of the ultra-precision fly-cutting machine tool process system, we can obtain a group of homogeneous linear equations about the unknown boundary state variables of the system.

[0100] S62. Based on the singular value decomposition technology, the total transfer equation of the ultra-precision fly-cutting machine tool process system is solved to obtain a homogeneous linear equation group about the unknown boundary state variables of the system, and its L linearly independent non-zero solutions are obtained:

[0101]

[0102] Multiplying both sides by the matrix N on the left simultaneously obtains L groups of non-zero solutions of the unknown boundary state vector of the system; where N is the orthogonal matrix used for singular value decomposition.

[0103] S63. After the characteristic vectors of each boundary of the system are obtained, the characteristic vectors of each connection point are recursively calculated from the input boundary to the output boundary of the system according to the transfer equations of each component, and the displacement of the corresponding point of the body component is extracted to obtain the vibration characteristics of the system.

[0104] S7. Combine the multi-body system transfer matrix method with the optimization genetic algorithm to achieve high-precision identification of the dynamic parameters of the machine tool system.

[0105] In step S7, the method of combining the multi-body system transfer matrix method with the optimized genetic algorithm to achieve high-precision identification of the dynamic parameters of the machine tool system is as follows:

[0106] S71. Minimizing the difference between the modal parameters obtained by simulation and experiment is used as the objective function, and a fitness function is established.

[0107] S72, through genetic algorithm selection, crossover, mutation and other operator search optimization.

[0108] S73. Find the minimum value of the objective function.

[0109] The high-precision identification of the dynamic parameters of the machine tool system is completed, and the identification accuracy of the dynamic model in the first 15 orders can reach more than 95%. The flow chart of the physical identification method based on the multi-body system transfer matrix method and the optimized genetic algorithm is as follows: Figure 5 shown.

[0110] Those skilled in the art will appreciate that the embodiments described herein are intended to help readers understand the principles of the present invention, and should be understood that the protection scope of the present invention is not limited to such specific statements and embodiments. Those skilled in the art can make various other specific variations and combinations that do not deviate from the essence of the present invention based on the technical revelations disclosed by the present invention, and these variations and combinations are still within the protection scope of the present invention.

Claims

1. A method for rapid identification of kinetic parameters, characterized in that: The following steps are involved: S1. Establish a multi-body system dynamics model of ultra-precision fly cutting machine tools; S2. Based on the typical multi-body system dynamics model of ultra-precision machine tool system, the multi-body system transfer matrix method is applied to establish the transfer matrix and transfer equation of the components; S3, using the method of dynamic model topology diagram to graphically describe the relationship between the state vectors of the body elements and the hinge elements in the multi-body system dynamics model, the position sequence number, the boundary sequence number, and the transfer direction, and obtain the transfer relationship between the state vectors of each element in the multi-body system dynamics model; S4, assembling the total transfer matrix of the system according to the transfer matrices of the components, and determining the total transfer equation of the system; S5. Determine the characteristic equation of the system and the natural frequencies of each order of the system according to the total transfer equation and boundary conditions of the precision fly-cutting machine tool system; S6. Obtain the characteristic vector and vibration characteristics of the system according to the component transfer equation; S7. Combine the multi-body system transfer matrix method with the optimization genetic algorithm to achieve high-precision identification of the dynamic parameters of the machine tool system.

2. A method for rapid identification of kinetic parameters according to claim 1, characterized in that: In step S1, the method for establishing the multi-body system dynamics model of the ultra-precision fly-cutting machine tool is as follows: S11. According to the connection mode and mutual motion relationship between the parts of the ultra-precision fly-cutting machine tool process system, its components are divided into 17 subsystems, each subsystem is regarded as a body element, and the body elements are connected by hinge elements. The numbers of the body elements and hinge elements are uniformly labeled; S12. According to the connection relationship between the subsystems, the multi-body system dynamics model of the ultra-precision fly-cutting machine tool is obtained.

3. A method for rapid identification of kinetic parameters according to claim 1, characterized in that: In step S2, according to a typical multi-body system dynamics model of an ultra-precision machine tool system, a multi-body system transfer matrix method is applied to establish the transfer matrix and transfer equation of the element as follows: S21. Establish the multi-body system dynamics equations of a typical ultra-precision machine tool system, including the transfer matrix of a spatial vibrating rigid body, the transfer matrix of a spatial vibrating beam, the transfer matrix of a spatial elastic hinge, the transfer matrix of a rotating spindle, the spindle air film stiffness, the stiffness of bolted joints, and the transfer matrix of a flexible body of arbitrary shape in space; S22. Select the corresponding matrix according to the component type, process the components as single-end input single-end output or multi-end input single-end output components, and obtain the transfer matrix and transfer equation of the components: Where i is the component number (all components are numbered consecutively starting from 1), r is the input point number of component i (the input points of component i are numbered consecutively starting from 1), and Z i,O and are the state vectors of the output point of element i and the rth input point, respectively. The input point I r The corresponding transfer matrix, N is the number of input points of element i; R T is the modal coordinate corresponding to the linear displacement of the input point or output point relative to its equilibrium position, Θ T is the modal coordinate corresponding to the angular displacement of the input point or output point relative to its equilibrium position, M T is the modal coordinate corresponding to the internal moment at the input point or output point.

4. A method for rapid identification of kinetic parameters according to claim 1, characterized in that: In step S4, the method of assembling the total transfer matrix and the total transfer equation of the system according to the transfer matrices of the components is as follows: S41. According to the relationship between the system boundary state vectors, the system total transfer equation is obtained: AT all WITH all =0 (3) Among them, U all is the total transfer matrix of the system, Z all is the system boundary state vector, which is an array composed of the boundary state vectors arranged in order; S42. Based on the multi-body system dynamics model of the ultra-precision machine tool system, the total transfer matrix U of the ultra-precision fly-cutting machine tool process system is obtained by applying the automatic derivation principle of the total transfer equation of the machine tool system. all : in, in, S43. Determine the system boundary state vector: S44. Determine the system boundary conditions: The total transfer equation of the system after substituting the boundary conditions is obtained: in, is an array of unknown boundary state variables of the system, is the square matrix obtained by deleting the columns corresponding to the zero elements of the system boundary state vector from the total transfer matrix.

5. A method for rapid identification of kinetic parameters according to claim 1, characterized in that: In step S5, the method for determining the characteristic equation of the system and the natural frequency of the system according to the total transfer equation and boundary conditions of the precision fly-cutting machine tool system is as follows: S51. Based on the total transfer equation and boundary conditions of the precision fly-cutting machine tool system, the characteristic equation of the system is obtained: S52, use the bisection method, parabola method, chord intercept method, golden section method and recursive search method to solve the equation and obtain the natural frequency ω of each order of the system k (k=1,2,…).

6. A method for rapid identification of kinetic parameters according to claim 1, characterized in that: In step S6, the method for obtaining the characteristic vector and vibration characteristics of the system according to the component transfer equation is as follows: S61. Substituting the natural frequencies of each order of the system into the total transfer equation of the ultra-precision fly-cutting machine tool process system, a homogeneous linear equation group about the unknown boundary state variables of the system is obtained; S62. Based on the singular value decomposition technology, the total transfer equation of the ultra-precision fly-cutting machine tool process system is solved to obtain a homogeneous linear equation group about the unknown boundary state variables of the system, and its L linearly independent non-zero solutions are obtained: Multiply both sides by the matrix N to obtain L sets of non-zero solutions of the unknown boundary state vector of the system; where N is the orthogonal matrix used for singular value decomposition; S63. After the characteristic vectors of each boundary of the system are obtained, the characteristic vectors of each connection point are recursively calculated from the input boundary to the output boundary of the system according to the transfer equations of each component, and the displacement of the corresponding point of the body component is extracted to obtain the vibration characteristics of the system.

7. A method for rapid identification of kinetic parameters according to claim 1, characterized in that: In step S7, the method of combining the multi-body system transfer matrix method with the optimized genetic algorithm to achieve high-precision identification of the dynamic parameters of the machine tool system is as follows: S71, minimizing the difference between the modal parameters obtained by simulation and the test as the objective function, and establishing a fitness function; S72, through genetic algorithm selection, crossover, mutation and other operator search optimization; S73. Find the minimum value of the objective function.

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