Hard and brittle material curved surface grinding preparation method, product, medium and equipment

Abstract

The invention discloses a hard and brittle material curved surface grinding preparation method, a product, a medium and equipment, and relates to the technical field of ultra-precision machining.The method comprises the steps that a geometric model of a hard and brittle material curved surface to be machined and an error value in the grinding preparation process are obtained; determining a three-dimensional coordinate of a cutter location contact in the grinding cutter path based on the geometric model; determining a rigid body transformation matrix by adopting a spinor theory according to structural parameters of a grinding preparation machine tool; obtaining an ideal grinding motion model of the machine tool based on the three-dimensional coordinates and the rigid body transformation matrix; compensating the ideal grinding motion model according to the error value of the grinding preparation process to obtain a compensated grinding motion model; and finishing the preparation of the hard and brittle curved surface by adopting the compensated grinding motion model. According to the hard and brittle material curved surface grinding preparation method, the product, the medium and the equipment, the machining efficiency and the machining quality of the hard and brittle material curved surface can be effectively improved.

Description

Technical Field

[0001] The present application relates to the field of ultra-precision machining technology, and in particular to a method, product, medium and equipment for grinding and preparing hard and brittle material curved surfaces. Background Art

[0002] With the development of electronics, medical treatment and advanced optical instruments, the demand for ultra-smooth curved surface components made of hard and brittle materials such as diamond, silicon carbide and sapphire is increasing rapidly. Since these materials are generally characterized by high hardness and brittleness, they are difficult to process and often require ultra-precision grinding technology for preparation. During the grinding process, due to the rapid wear of the grinding wheel, large surface errors are very likely to occur. The detached abrasives can also easily cause scratches on the processed surface, thereby affecting the processing efficiency and quality of the components. Summary of the invention

[0003] The purpose of this application is to provide a method, product, medium and equipment for grinding and preparing hard and brittle material surfaces, which can effectively improve the processing efficiency and processing quality of hard and brittle material surfaces.

[0004] To achieve the above objectives, this application provides the following solutions:

[0005] In a first aspect, the present application provides a method for grinding and preparing a hard and brittle material surface, comprising:

[0006] Obtaining a geometric model of a hard and brittle material surface to be processed and an error value of a grinding preparation process; the error value of the grinding preparation process includes a motion error value of a grinding preparation machine tool, an installation error value of the grinding preparation machine tool, and a real-time wear error value of a grinding wheel;

[0007] Determine the three-dimensional coordinates of the tool position contact points in the grinding tool path based on the geometric model;

[0008] According to the structural parameters of the grinding and preparation machine tool, the rigid body transformation matrix is ​​determined by using the screw theory; the structural parameters include the position coordinates of each axis of the grinding and preparation machine tool relative to the basic coordinate system and the corresponding motion stroke;

[0009] Obtaining an ideal grinding motion model of a machine tool based on the three-dimensional coordinates and the rigid body transformation matrix;

[0010] Compensating the ideal grinding motion model according to the error value of the grinding preparation process to obtain a compensated grinding motion model;

[0011] The compensated grinding motion model is used to complete the preparation of hard and brittle surfaces.

[0012] Optionally, the step of obtaining a geometric model of a hard and brittle material surface to be processed and an error value of a grinding preparation process specifically includes:

[0013] The geometric model of the hard and brittle material surface to be processed is obtained through UG software; the motion error value and installation error value of the grinding preparation machine tool are measured by laser interferometer or laser displacement sensor; the real-time wear error value of the grinding wheel is obtained by line laser measurement.

[0014] Optionally, determining the three-dimensional coordinates of the tool position contact points in the grinding tool path based on the geometric model specifically includes:

[0015] Output the grinding tool path of the hard and brittle material surface to be processed through the geometric model and save it as a text format file;

[0016] The grinding tool path is input into MATLAB software, and the three-dimensional coordinates of the tool position contact points in the grinding tool path are obtained through keyword recognition.

[0017] Optionally, the grinding preparation machine tool is a six-axis machine tool, including an X-axis, a Y-axis, a Z-axis, a U-axis, an A-axis and a W-axis; wherein the U-axis and the Z-axis are used to position the hard and brittle material surface to be processed; the hard and brittle material surface to be processed is error compensated by moving in the Y-axis direction; the hard and brittle material surface to be processed is fed by rotating in the A-axis and W-axis directions; and the grinding wheel is ground by swinging in the X-axis direction.

[0018] Optionally, the method of determining a rigid body transformation matrix using screw theory according to the structural parameters of the grinding machine tool specifically includes:

[0019] According to the structural parameters of the grinding preparation machine tool, the grinding wheel coordinate system, the workpiece coordinate system and the basic coordinate system are established respectively;

[0020] Based on the grinding wheel coordinate system, workpiece coordinate system and basic coordinate system, the rigid body transformation matrix is ​​obtained through the screw theory. Among them, g rn (θ1,θ2…θ n ) is the nth axis of the grinding preparation machine relative to the basic coordinate system [g m (0)], with n = 1, 2, ..., 6; Prepare the homogeneous transformation matrix corresponding to the nth axis of the machine tool for grinding; The rigid body motion spiral amount of the nth axis of the grinding preparation machine tool; θ n The movement displacement of the nth axis of the machine tool prepared for grinding.

[0021] Optionally, obtaining an ideal grinding motion model of a machine tool based on the three-dimensional coordinates and the rigid body transformation matrix specifically includes:

[0022] Through inverse kinematics planning, the three-dimensional coordinates are substituted into the rigid body transformation matrix to construct an ideal grinding motion model of the machine tool. Among them, [g bt (0)] is the workpiece coordinate system under ideal conditions; [g bw (0)] -1 is the grinding wheel coordinate system under ideal conditions [g bw (0)]; is the homogeneous transformation matrix corresponding to the A axis under ideal conditions; is the homogeneous transformation matrix corresponding to the U axis under ideal conditions; is the homogeneous transformation matrix corresponding to the W axis under ideal conditions; is the homogeneous transformation matrix corresponding to the Y axis under ideal conditions; is the homogeneous transformation matrix corresponding to the X-axis under ideal conditions; It is the homogeneous transformation matrix corresponding to the Z axis under ideal conditions.

[0023] Optionally, the expression of the compensated grinding motion model is: Among them, [g bt_cps (0)] is the workpiece coordinate system after compensation; is the motion matrix corresponding to the A-axis after compensation; is the motion matrix corresponding to the U axis after compensation; is the motion matrix corresponding to the W axis after compensation; is the motion matrix corresponding to the Y axis after compensation; is the motion matrix corresponding to the compensated X-axis; It is the motion matrix corresponding to the Z axis after compensation.

[0024] In a second aspect, the present application provides a computer program product, including a computer program, which, when executed by a processor, implements the hard and brittle material curved surface grinding preparation method.

[0025] In a third aspect, the present application provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the method for preparing hard and brittle material curved surface by grinding.

[0026] In a fourth aspect, the present application provides a computer device, comprising: a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to implement the hard and brittle material curved surface grinding preparation method.

[0027] According to the specific embodiments provided in this application, this application discloses the following technical effects:

[0028] The present application provides a method, product, medium and equipment for grinding and preparing hard and brittle material surfaces. By establishing a geometric model of the hard and brittle material surface to be processed, the three-dimensional coordinates of the tool position contact points in the grinding tool path are obtained and the kinematic model of the machine tool is constructed, thereby obtaining an ideal grinding motion model; then, considering the motion error value, installation error value and real-time wear error value of the grinding wheel of the grinding preparation machine tool, the ideal grinding motion model is compensated based on the error value to obtain a compensated grinding motion model. The present application uses the compensated grinding motion model obtained by the hard and brittle material surface grinding motion planning method based on error compensation to perform ultra-precision grinding of hard and brittle materials, which can effectively improve the processing efficiency and processing quality of the hard and brittle material surfaces. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0030] Figure 1 Flow chart of the method for preparing hard and brittle material surface grinding provided in this application;

[0031] Figure 2 A schematic diagram of the curved surface structure of the hard and brittle material to be processed provided in this application;

[0032] Figure 3 A flowchart for obtaining the three-dimensional coordinates of the tool position contact points in the grinding tool path provided by this application;

[0033] Figure 4 Schematic diagram of the grinding preparation machine tool structure provided for this application;

[0034] Figure 5 Schematic diagram of the grinding process provided for this application;

[0035] Figure 6 A comparison diagram of the tool position contact points in the uncompensated grinding tool path provided by the present application and the tool position contact points in the ideal grinding tool path;

[0036] Figure 7 A comparison diagram of the tool position contact points in the compensated grinding tool path provided by the present application and the tool position contact points in the ideal grinding tool path;

[0037] Figure 8 The sapphire curved surface parts processing diagram provided for this application. DETAILED DESCRIPTION

[0038] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0039] In order to make the above-mentioned objects, features and advantages of the present application more obvious and easy to understand, the present application is further described in detail below in conjunction with the accompanying drawings and specific implementation methods.

[0040] like Figure 1 As shown, the present application discloses a method for preparing a hard and brittle material surface by grinding, comprising:

[0041] The hard and brittle material curved surface (curved surface part) to be processed includes convex curved surface structures such as spherical surface, aspherical surface and quadratic surface. Figure 2 The curved surface part shown in the figure is used as an example to explain the method of grinding and preparing the hard and brittle material surfaces in detail.

[0042] Step 1: Obtain the geometric model of the hard and brittle material surface to be machined and the error value of the grinding preparation process.

[0043] Specifically, this application is established through general 3D software such as UG Figure 2 The geometric model of the hard and brittle material surface to be processed is shown, and the geometric model is subsequently used to directly output the grinding tool path of the hard and brittle material surface to be processed. The hard and brittle material surface grinding preparation method of the present application is mainly a hard and brittle material surface grinding motion planning method based on error compensation, and the error values ​​involved in the grinding preparation process include the motion error value of the grinding preparation machine tool, the installation error value of the grinding preparation machine tool, and the real-time wear error value of the grinding wheel. The present application obtains the motion error value and the installation error value of the grinding preparation machine tool by measuring with a laser interferometer or a laser displacement sensor, and obtains the real-time wear error value of the grinding wheel by line laser measurement.

[0044] Step 2: Determine the three-dimensional coordinates of the tool contact points in the grinding tool path based on the geometric model.

[0045] First, based on the geometric model of the hard and brittle material surface to be processed obtained in step 1, the tool position contacts of the hard and brittle material surface to be processed under the general three-axis milling machine are directly output, that is, the grinding tool path (grinding tool path NC code) is directly output. Then, the grinding tool path NC code is saved as a file readable and writable by MATLAB software such as text, and keyword recognition is performed through MATLAB software to obtain the three-dimensional coordinates of the tool position contacts in the grinding tool path. Specifically, keyword recognition includes key character positioning and follow-up coordinate point extraction: the X, Y, and Z characters in the G code are set as key characters, and then the characters in the G code file are extracted one by one to determine whether they are keywords. If so, the next adjacent character is extracted, which is the coordinate point corresponding to the key character. The obtained grinding tool path is thus converted into the three-dimensional coordinates of the tool position contacts in the grinding tool path, and saved as X, Y, and Z vector coordinates. The vector coordinates are coordinates in the Cartesian coordinate system. In subsequent operations, they need to be converted into the motion coordinates of the following six-axis machine tool through rigid body motion transformation. The specific acquisition process of the three-dimensional coordinates of the tool position contacts in the grinding tool path is as follows: Figure 3 shown.

[0046] Step 3: According to the structural parameters of the grinding machine tool, the rigid body transformation matrix is ​​determined using the screw theory.

[0047] The grinding process of the hard and brittle material surface to be processed in this application is completed by machining the end surface of a simple cylindrical grinding wheel. The grinding preparation machine tool used is a six-axis machine tool including six motion axes (axis, axis) of X, Y, Z, U, A and W. Its structural diagram is as follows Figure 4 As shown, it includes a tool chain and a workpiece chain. Among them, the tool chain is composed of an X-axis and a Z-axis; the workpiece chain is composed of a Y-axis, a W-axis, a U-axis and an A-axis. The Y-axis is installed on the bed of the six-axis machine tool, the W-axis is vertically installed on the Y-axis, the U-axis is vertically installed on the W-axis, the A-axis is installed on the U-axis and the curved surface part to be processed (the curved surface of the hard and brittle material to be processed) is installed on the A-axis. Based on the connection relationship, the specific movement process of the swing grinding of the curved surface of the hard and brittle material to be processed is: the curved surface part to be processed is positioned by the U-axis and the Z-axis, the Y-axis is used to compensate for the curved surface error, and the curved surface part to be processed can move in two rotation directions of the A-axis and the W-axis, and the feed creates a curved surface structure. The swing grinding forms swing grinding through the reciprocating motion of the X-axis in the tangent direction of the curved surface, so as to ensure that the entire end face of the grinding wheel participates in the curved surface processing and reduce the influence of the grinding wheel wear on the curved surface processing accuracy and quality. That is, the oscillating grinding motion of the hard and brittle material to be processed in this application is positioned by the U axis and the Z axis, the Y axis is used for surface error compensation, the A axis and the W axis are used for workpiece feeding to form a surface structure, and the X axis is used for grinding wheel oscillation grinding. The specific grinding process diagram is as follows Figure 5 Therefore, the structural parameters obtained above include the position coordinates of each axis of the grinding preparation machine tool relative to the basic coordinate system and the corresponding motion stroke.

[0048] After obtaining the above structural parameters, this application uses the screw theory to transform the rigid body motion based on the actual structural parameters (structural parameters) of the grinding preparation machine tool to obtain the rigid body transformation matrix. Specifically, first, according to the factory drawing annotations of the grinding preparation machine tool, the grinding wheel coordinate system (tool coordinate system), workpiece coordinate system and basic coordinate system of the grinding preparation machine tool are established, wherein the coordinate origin of the basic coordinate system is the mechanical coordinate zero point of the machine tool, that is, the dimensional reference during the installation of each motion axis.

[0049] Specifically, the matrix of the workpiece coordinate system to the basic coordinate system obtained by using the screw theory to transform the rigid body motion is the rigid body transformation matrix:

[0050]

[0051] In the formula, [g m (0)] is the basic coordinate system, which can be expressed as:

[0052]

[0053] In the formula, g rn (θ1,θ2…θ n ) is the nth axis of the six-axis machine tool relative to the basic coordinate system [g m (0)], n = 1, 2, ..., 6 correspond to the X axis, Y axis, Z axis, U axis, A axis and W axis respectively; if the nth axis is the axis where the workpiece is located, it is the matrix for transforming the workpiece coordinate system to the basic coordinate system; if the nth axis is the axis where the grinding wheel is located, it is the matrix for transforming the grinding wheel coordinate system to the basic coordinate system, the axis where the workpiece is located includes the U axis, the A axis and the W axis, and the axis where the grinding wheel is located includes the X axis, the Y axis and the Z axis; I 3×3 is a 3×3 unit matrix; θ n The motion command for the nth axis of the six-axis machine tool, that is, the motion displacement setting, the position of each motion axis can be collectively referred to as θ. When the nth axis is the W axis, the angular displacement (motion displacement) of the W axis is θ w , the unit is rad, when the nth axis is the A axis, the angular displacement (motion displacement) of the A axis is θ A , the unit is rad, when the nth axis is the X axis, the movement displacement of the X axis is x, when the nth axis is the Y axis, the movement displacement of the Y axis is y, when the nth axis is the Z axis, the movement displacement of the Z axis is z, when the nth axis is the U axis, the movement displacement of the U axis is u; when the basic coordinate system [g m (0)] is established at the mechanical zero point of the machine tool, t0 is the zero vector, and when the basic coordinate system [g m (0)] is established at other points of the machine tool, t0 is a column vector composed of the mechanical coordinate values ​​of the X-axis, Y-axis and Z-axis of the six-axis machine tool in the basic coordinate system; It is a unified description of the homogeneous transformation matrix corresponding to each motion axis of the six-axis machine tool, including Etc., which can be specifically expressed as:

[0054]

[0055] Wherein, I is the above I 3×3 Abbreviation of is the spiral quantity of rigid body motion, and its expression is:

[0056]

[0057] ν=-ω×q+hω,‖ω‖=1,θ≠0 (5)

[0058] Where ω is the unit vector of the rotation axis (A axis and W axis) in the motion axis, is the antisymmetric matrix of ω; q is the coordinate of the motion axis in the basic coordinate system (obtained from the factory machine tool drawings or related data); h is the pitch of the screw motion; ‖‖ indicates the norm.

[0059] Step 4: Obtain an ideal grinding motion model of the machine tool based on the three-dimensional coordinates and the rigid body transformation matrix.

[0060] Through inverse kinematics planning, the three-dimensional coordinates of the curved surface part are substituted into the rigid body transformation matrix obtained in step 3 to obtain the ideal grinding motion model of the machine tool, that is, the ideal grinding motion model without considering the effect of errors.

[0061] For the six-axis machine tool of the present application, without considering the error, the ideal motion of the grinding wheel to the workpiece is performed, that is, the ideal grinding motion model g wt _ ideal (x,y,z,u,θ w ,θ A ) can be defined as:

[0062]

[0063] In the formula, [g bt (0)] is the workpiece coordinate system under ideal conditions, [g bw (0)] -1 is the grinding wheel coordinate system under ideal conditions [g bw (0)], both of which are related to the basic coordinate system [g m (0)] can also be obtained by formula (1), that is, formula (1) is a general formula. The matrix of transforming the workpiece coordinate system to the basic coordinate system and the matrix of transforming the grinding wheel coordinate system to the basic coordinate system can also be obtained by formula (1). This formula can be used to express all motion systems in a general sense; (0) represents the coordinate origin. is the homogeneous transformation matrix (ideal motion matrix) corresponding to the A axis under ideal conditions; is the homogeneous transformation matrix corresponding to the U axis under ideal conditions; is the homogeneous transformation matrix corresponding to the W axis under ideal conditions; is the homogeneous transformation matrix corresponding to the Y axis under ideal conditions; is the homogeneous transformation matrix corresponding to the X-axis under ideal conditions; It is the homogeneous transformation matrix corresponding to the Z axis under ideal conditions. and are the rigid body motion spirals of A-axis, U-axis, W-axis, Y-axis, X-axis and Z-axis respectively under ideal conditions, referred to as rigid body ideal motion spirals; θ Ai ,ui,θ wi , yi, xi and zi are the motion displacements of A-axis, U-axis, W-axis, Y-axis, X-axis and Z-axis respectively under ideal conditions.

[0064] Step 5: Compensating the ideal grinding motion model according to the error value of the grinding preparation process to obtain a compensated grinding motion model.

[0065] Considering the motion errors of each motion axis of the machine tool, the installation errors of the motion axis, and the real-time wear changes of the grinding wheel during the grinding process, the machine tool motion errors and the real-time wear of the grinding wheel are compensated into the grinding tool path through forward motion planning, that is, the machine tool motion errors and the real-time wear of the grinding wheel are substituted into the ideal grinding motion model g. wt _ ideal (x,y,z,u,θ w ,θ A ), and obtain the grinding motion model after compensation including machine tool error and grinding wheel wear.

[0066] By measuring the machine tool motion accuracy and grinding wheel wear, the motion error, installation error and wear error compensation matrix are established, that is, error compensation is performed, and the ideal grinding motion model is introduced to obtain the compensated grinding motion model, which is as follows:

[0067] Taking the rotating axis A as an example, considering the influence of installation error and motion error, its actual motion can be expressed as θ A is the motion command of the rotation axis A, and the corresponding installation error can be expressed as The motion error can be expressed as Use laser interferometer to measure geometric errors. According to the principle of laser interferometry, the error elements are defined in the workpiece coordinate system. The error compensation matrix should be multiplied by the ideal motion matrix of the rotation axis A. in It is the ideal motion spiral of a rigid body.

[0068]

[0069] Where lrt is 1 for left multiplication and 0 for right multiplication, depending on the measuring instrument.

[0070] The actual motion model of the six-axis machine tool can be expressed as g wt _ actual (x,y,z,u,θ w ,θ A ), the specific process of obtaining is as follows.

[0071]

[0072] Among them, [gbt_actual(0)] is the actual workpiece coordinate system; The real-time wear amount of the grinding wheel; is the actual motion matrix corresponding to the A axis; is the actual motion matrix corresponding to the U axis; is the actual motion matrix corresponding to the W axis; is the actual motion matrix corresponding to the Y axis; is the actual motion matrix corresponding to the X-axis; is the actual motion matrix corresponding to the Z axis. They are the actual rigid body motion spiral amounts of the A-axis, U-axis, W-axis, Y-axis, X-axis, and Z-axis respectively.

[0073] The comparison between the ideal tool position and the actual tool position obtained according to the ideal grinding motion model and the actual motion model is as follows: Figure 6 As shown. Figure 6 It can be seen that the actual motion model g wt _ actual (x,y,z,u,θ w ,θ A The motion error contained in ) will cause the grinding tool path to deviate from the ideal tool path. Therefore, a compensation matrix for motion error, installation error and grinding wheel wear is established. Through forward motion planning, the machine tool motion error compensation Installation error compensation And real-time grinding wheel wear compensation Substituting into the ideal grinding motion model, the final motion transformation of the machine tool (grinding motion model after compensation) can be expressed as g wt _ cps (x,y,z,u,θ w ,θ A ), the specific calculation process is as follows.

[0074]

[0075] Among them, [g bt_cps (0)] is the workpiece coordinate system after compensation of the actual workpiece coordinate system; is the motion matrix of the A axis after compensation, that is, the actual tool position point The knife position after compensation; is the motion matrix corresponding to the A-axis after compensation; is the motion matrix corresponding to the U axis after compensation; is the motion matrix corresponding to the W axis after compensation; is the motion matrix corresponding to the Y axis after compensation; is the motion matrix corresponding to the compensated X-axis; It is the motion matrix corresponding to the Z axis after compensation. and are the rigid body motion spiral amounts of the compensated A-axis, U-axis, W-axis, Y-axis, X-axis and Z-axis respectively; θ Ac ,uc,θ wc , yc, xc and zc are the motion displacements of A-axis, U-axis, W-axis, Y-axis, X-axis and Z-axis respectively after compensation.

[0076] The comparison between the compensated tool position and the ideal tool position obtained based on the ideal grinding motion model and the compensated grinding motion model is shown in Figure 2. Figure 7 As shown by Figure 7 It can be seen that the overlap rate between the tool position after compensation and the ideal tool position is high, which can effectively improve the accuracy of hard and brittle surface preparation.

[0077] Step 6: Use the compensated grinding motion model to complete the preparation of the hard and brittle surface.

[0078] After the compensated grinding motion model is determined through the above steps, the compensated grinding motion model is used to complete the preparation of the hard and brittle surface, which can effectively improve the processing efficiency and processing quality of the hard and brittle material surface. As a specific embodiment, the hard and brittle material surface grinding preparation method of the present application is used to process a sapphire curved surface part. The morphology of the sapphire curved surface part obtained by grinding is as follows: Figure 8 shown.

[0079] In some embodiments, the present application also provides a computer program product, including a computer program, which implements the hard and brittle material surface grinding preparation method when executed by a processor.

[0080] In some embodiments, the present application also provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the hard and brittle material curved surface grinding preparation method.

[0081] In some embodiments, the present application also provides a computer device, including a processor, a memory, an input / output interface (I / O for short), a communication interface, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to implement the method for preparing hard and brittle material curved surface by grinding.

[0082] The processor, memory and input / output interface are connected via a system bus, and the communication interface is connected to the system bus via the input / output interface. The processor of the computer device is used to provide computing and control capabilities. The memory of the computer device includes a non-volatile storage medium and an internal memory. The non-volatile storage medium stores an operating system, a computer program and a database. The internal memory provides an environment for the operation of the operating system and the computer program in the non-volatile storage medium. The database of the computer device is used to store pending transactions. The input / output interface of the computer device is used to exchange information between the processor and an external device. The communication interface of the computer device is used to communicate with an external terminal via a network connection. When the computer program is executed by the processor, the hard and brittle material surface grinding preparation method is implemented.

[0083] It should be noted that the object information (including but not limited to object device information, object personal information, etc.) and data (including but not limited to data used for analysis, stored data, displayed data, etc.) involved in this application are all information and data authorized by the object or fully authorized by all parties, and the collection, use and processing of relevant data need to comply with relevant laws, regulations and standards of relevant countries and regions.

[0084] Those skilled in the art can understand that all or part of the processes in the above-mentioned embodiment methods can be completed by instructing the relevant hardware through a computer program, and the computer program can be stored in a non-volatile computer-readable storage medium. When the computer program is executed, it can include the processes of the embodiments of the above-mentioned methods. Among them, any reference to the memory, database or other medium used in the embodiments provided in the present application can include at least one of non-volatile and volatile memory. Non-volatile memory can include read-only memory (ReadOnlyMemory, ROM), magnetic tape, floppy disk, flash memory, optical memory, high-density embedded non-volatile memory, resistive random access memory (ReRAM), magnetic random access memory (MRAM), ferroelectric random access memory (FRAM), phase change memory (PCM), graphene memory, etc. Volatile memory can include random access memory (RAM) or external cache memory, etc. As an illustration and not limitation, RAM can be in various forms, such as static random access memory (SRAM) or dynamic random access memory (DRAM). The database involved in each embodiment provided in this application may include at least one of a relational database and a non-relational database. Non-relational databases may include distributed databases based on blockchains, etc., but are not limited thereto. The processor involved in each embodiment provided in this application may be a general-purpose processor, a central processing unit, a graphics processor, a digital signal processor, a programmable logic device, a data processing logic device based on quantum computing, etc., but are not limited thereto.

[0085] The technical features of the above embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above embodiments are 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.

[0086] This article uses specific examples to illustrate the principles and implementation methods of this application. The description of the above embodiments is only used to help understand the method and core ideas of this application. At the same time, for those skilled in the art, according to the ideas of this application, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as limiting this application.

Claims

1. A method for grinding and preparing hard and brittle material surfaces, characterized in that: include: Obtaining a geometric model of a hard and brittle material surface to be processed and an error value of a grinding preparation process; the error value of the grinding preparation process includes a motion error value of a grinding preparation machine tool, an installation error value of the grinding preparation machine tool, and a real-time wear error value of a grinding wheel; Determine the three-dimensional coordinates of the tool position contact points in the grinding tool path based on the geometric model; According to the structural parameters of the grinding and preparation machine tool, the rigid body transformation matrix is ​​determined by using the screw theory; the structural parameters include the position coordinates of each axis of the grinding and preparation machine tool relative to the basic coordinate system and the corresponding motion stroke; Obtaining an ideal grinding motion model of a machine tool based on the three-dimensional coordinates and the rigid body transformation matrix; Compensating the ideal grinding motion model according to the error value of the grinding preparation process to obtain a compensated grinding motion model; The compensated grinding motion model is used to complete the preparation of hard and brittle surfaces.

2. The method for preparing hard and brittle material curved surface by grinding according to claim 1, characterized in that: The step of obtaining the geometric model of the hard and brittle material surface to be processed and the error value of the grinding preparation process specifically includes: The geometric model of the hard and brittle material surface to be processed is obtained through UG software; the motion error value and installation error value of the grinding preparation machine tool are measured by laser interferometer or laser displacement sensor; the real-time wear error value of the grinding wheel is obtained by line laser measurement.

3. The method for preparing hard and brittle material curved surface by grinding according to claim 1, characterized in that: Determining the three-dimensional coordinates of the tool position contact points in the grinding tool path based on the geometric model specifically includes: Output the grinding tool path of the hard and brittle material surface to be processed through the geometric model and save it as a text format file; The grinding tool path is input into MATLAB software, and the three-dimensional coordinates of the tool position contact points in the grinding tool path are obtained through keyword recognition.

4. The method for preparing hard and brittle material curved surface by grinding according to claim 1, characterized in that: The grinding preparation machine tool is a six-axis machine tool, including an X-axis, a Y-axis, a Z-axis, a U-axis, an A-axis and a W-axis; wherein the U-axis and the Z-axis are used to position the hard and brittle material surface to be processed; the hard and brittle material surface to be processed is error compensated by moving in the Y-axis direction; the hard and brittle material surface to be processed is fed by rotating in the A-axis and W-axis directions; and the grinding wheel is ground by swinging in the X-axis direction.

5. The method for preparing hard and brittle material curved surface by grinding according to claim 4, characterized in that: The rigid body transformation matrix is ​​determined by using the screw theory according to the structural parameters of the grinding machine tool, which specifically includes: According to the structural parameters of the grinding preparation machine tool, the grinding wheel coordinate system, the workpiece coordinate system and the basic coordinate system are established respectively; Based on the grinding wheel coordinate system, workpiece coordinate system and basic coordinate system, the rigid body transformation matrix is ​​obtained through the screw theory. Among them, g rn (θ1,θ2…θ n ) is the nth axis of the grinding preparation machine relative to the basic coordinate system [g m (0)], with n = 1, 2, ..., 6; Prepare the homogeneous transformation matrix corresponding to the nth axis of the machine tool for grinding; The rigid body motion spiral amount of the nth axis of the grinding preparation machine tool; θ n The movement displacement of the nth axis of the machine tool prepared for grinding.

6. The method for preparing hard and brittle material curved surface by grinding according to claim 5, characterized in that: The ideal grinding motion model of the machine tool is obtained based on the three-dimensional coordinates and the rigid body transformation matrix, specifically comprising: Through inverse kinematics planning, the three-dimensional coordinates are substituted into the rigid body transformation matrix to construct an ideal grinding motion model of the machine tool. Among them, [g bt (0)] is the workpiece coordinate system under ideal conditions; [g bw (0)] -1 is the grinding wheel coordinate system under ideal conditions [g bw (0)]; is the homogeneous transformation matrix corresponding to the A axis under ideal conditions; is the homogeneous transformation matrix corresponding to the U axis under ideal conditions; is the homogeneous transformation matrix corresponding to the W axis under ideal conditions; is the homogeneous transformation matrix corresponding to the Y axis under ideal conditions; is the homogeneous transformation matrix corresponding to the X-axis under ideal conditions; It is the homogeneous transformation matrix corresponding to the Z axis under ideal conditions.

7. The method for preparing hard and brittle material curved surface by grinding according to claim 6, characterized in that: The expression of the compensated grinding motion model is: Among them, [g bt_cps (0)] is the workpiece coordinate system after compensation; is the motion matrix corresponding to the A-axis after compensation; is the motion matrix corresponding to the U axis after compensation; is the motion matrix corresponding to the W axis after compensation; is the motion matrix corresponding to the Y axis after compensation; is the motion matrix corresponding to the compensated X-axis; It is the motion matrix corresponding to the Z axis after compensation.

8. A computer program product, comprising a computer program, characterized in that When the computer program is executed by a processor, the method for preparing hard and brittle material curved surface by grinding as described in any one of claims 1 to 7 is implemented.

9. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the method for preparing hard and brittle material curved surface by grinding as described in any one of claims 1 to 7 is implemented.

10. A computer device comprising: A memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to implement the hard and brittle material curved surface grinding preparation method described in any one of claims 1 to 7.

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