Machine tool precision compensation method and apparatus, and storage medium and electronic device

Abstract

The embodiments of the present application relate to the technical field of multi-axis machine tools. Disclosed are a machine tool precision compensation method and apparatus, and a storage medium and an electronic device. The method comprises: obtaining three-dimensional coordinates of an actual ball center of a ball head when swing heads A and B of a machine tool are at actual swing positions; respectively obtaining vector difference information in each coordinate axis direction according to three-dimensional coordinates of a reference ball center and the three-dimensional coordinates of the actual ball center; and obtaining a target compensation value according to a parameter compensation value of the machine tool and the vector difference information, wherein the target compensation value is used for precision compensation for the machine tool at the actual swing positions. In the present application, a vector difference between the coordinates of a ball center at an initial position and the coordinates of the ball center at an actual position is used as a precision deviation, and an inherent parameter compensation value of a machine tool is combined with the actually obtained precision deviation, so as to comprehensively obtain a target compensation value to implement more accurate compensation, which is automatically executed by means of program calling, such that manual intervention is avoided, human errors are reduced, and precision detection is more efficient and more stable, thereby effectively improving machine tool precision compensation quality.

Description

Machine tool precision compensation method, device, storage medium and electronic equipment Technical Field

[0001] The present application relates to the technical field of multi-axis machine tools, and in particular to a machine tool precision compensation method, device, storage medium and electronic equipment. Background Art

[0002] With the continuous development of science and technology, CNC machine tools, as industrial mother machines, have been continuously iterated and improved in structural design and functional optimization. The five-axis linkage technology of CNC machine tools has become more and more mature. RTCP accuracy, as the core accuracy indicator of high-end CNC machine tools, directly affects the processing quality of CNC machine tools.

[0003] At present, the RTCP accuracy of machine tools is usually detected manually using tools such as micrometers and test rods. The detection accuracy is poor and the efficiency is low. As a result, the compensation quality based on the test results is low, which greatly reduces the working effect of the machine tool.

[0004] Summary of the Invention

[0005] The main purpose of this application is to provide a machine tool precision compensation method, device, storage medium and electronic equipment, aiming to solve the problem of low quality of machine tool precision compensation in the prior art.

[0006] To achieve the above-mentioned purpose, the technical solutions adopted in the embodiments of the present application are as follows:

[0007] In a first aspect, an embodiment of the present application provides a machine tool precision compensation method, which is applied to a machine tool precision compensation device. The device includes a calibration rod and a probe. The calibration rod includes a ball head. The probe is installed on the workbench of a BA double-swing head five-axis machine tool. The calibration rod is installed on a tool magazine, including the following steps:

[0008] Use the probe to obtain the actual three-dimensional coordinates of the ball center of the machine tool's A and B swing heads when they are in the actual swing position;

[0009] According to the three-dimensional coordinates of the reference sphere center and the three-dimensional coordinates of the actual sphere center, the vector difference information in each coordinate axis direction is obtained respectively; wherein the three-dimensional coordinates of the reference sphere center are obtained when the A and B swing heads of the machine tool are in the initial position;

[0010] A target compensation value is obtained according to the parameter compensation value and vector difference information of the machine tool; wherein the target compensation value is used to compensate the accuracy of the machine tool at the actual swing position.

[0011] In a possible implementation of the first aspect, before obtaining vector difference information in each coordinate axis direction based on the three-dimensional coordinates of the reference sphere center and the actual sphere center, the machine tool accuracy compensation method further includes:

[0012] Use the probe to obtain the X-axis coordinates and Y-axis coordinates of the reference sphere center of the machine tool's A and B swing heads in the initial position;

[0013] Move the linear axis of the machine tool so that the probe is located at a position with the same coordinates as the X-axis coordinate and the Y-axis coordinate of the center of the reference sphere, and obtain the Z-axis coordinate of the top of the ball head;

[0014] According to the distance from the rotation center to the spindle end face and the Z-axis coordinate of the top of the ball head, the Z-axis coordinate of the reference ball center is obtained;

[0015] The three-dimensional coordinates of the reference sphere center are obtained according to the X-axis coordinate of the reference sphere center, the Y-axis coordinate of the reference sphere center, and the Z-axis coordinate of the reference sphere center.

[0016] In a possible implementation of the first aspect, before obtaining the Z-axis coordinate of the reference sphere center based on the distance from the rotation center to the spindle end face and the Z-axis coordinate of the top of the ball head, the machine tool precision compensation method further includes:

[0017] Obtaining first and second spherical center coordinates of the ball head within a swing range of the swing head of the machine tool and at a swing position symmetrical to an initial position of the swing head;

[0018] The distance from the rotation center to the spindle end face is obtained according to the length of the calibration rod, the simple pendulum angle of the pendulum head, the coordinates of the first sphere center, and the coordinates of the second sphere center.

[0019] In a possible implementation of the first aspect, obtaining the distance from the rotation center to the spindle end face according to the length of the calibration rod, the pendulum angle of the pendulum head, the first sphere center coordinates, and the second sphere center coordinates includes:

[0020] According to the length of the calibration rod, the simple pendulum angle of the pendulum head, the coordinates of the first sphere center and the second sphere center, the distance from the rotation center to the spindle end face within the swing range of the pendulum head is calculated, and the distance from the first rotation center to the spindle end face and the distance from the second rotation center to the spindle end face are obtained;

[0021] The distance from the rotation center to the spindle end face is obtained according to the average value of the distance from the first rotation center to the spindle end face and the distance from the second rotation center to the spindle end face.

[0022] In a possible implementation of the first aspect, obtaining the actual three-dimensional coordinates of the center of the ball head of the machine tool's A and B swing heads at the actual swing positions using a probe includes:

[0023] Using the probe and the multi-layer roundness coordinate calculation method, the actual three-dimensional coordinates of the ball center of the machine tool's A and B swing heads in the actual swing position are obtained.

[0024] In one possible implementation of the first aspect, a probe is used to obtain the actual three-dimensional coordinates of the center of the ball head of the machine tool's A and B swing heads when the swing heads are in actual swing positions using a multi-layer roundness coordinate calculation method, including:

[0025] Use the probe to obtain the multi-layer roundness coordinates on the ball head of the machine tool's A and B swing heads at the actual swing position;

[0026] According to the average value of each layer of roundness coordinates in the multi-layer roundness coordinates on the ball head, several single-layer roundness coordinates are obtained;

[0027] The actual three-dimensional coordinates of the ball center are obtained based on the average value of several single-layer roundness coordinates.

[0028] In a possible implementation of the first aspect, after obtaining vector difference information in each coordinate axis direction based on the three-dimensional coordinates of the reference sphere center and the actual sphere center, the machine tool accuracy compensation method further includes:

[0029] It is determined whether the vector difference information in each coordinate axis direction is greater than a preset precision error threshold. If the result of the determination is yes, a machine tool alarm process is executed.

[0030] In a second aspect, an embodiment of the present application provides a machine tool precision compensation device, the device including a calibration rod and a probe, the calibration rod including a ball head, the probe being mounted on a workbench of a BA double-swing head five-axis machine tool, the calibration rod being mounted on a tool magazine, and the device further including:

[0031] The measuring module is used to obtain the actual three-dimensional coordinates of the center of the ball head of the machine tool's A and B swing heads when they are in the actual swing position using a probe;

[0032] A vector difference acquisition module is used to obtain vector difference information in each coordinate axis direction based on the three-dimensional coordinates of the reference sphere center and the three-dimensional coordinates of the actual sphere center. The three-dimensional coordinates of the reference sphere center are obtained when the A and B swing heads of the machine tool are in their initial positions.

[0033] The compensation module is used to obtain a target compensation value based on the parameter compensation value and vector difference information of the machine tool; wherein the target compensation value is used to compensate for the accuracy of the machine tool under the actual swing position.

[0034] In a third aspect, an embodiment of the present application provides a computer-readable storage medium storing a computer program. When the computer program is loaded and executed by a processor, the machine tool precision compensation method provided in any one of the first aspects above is implemented.

[0035] In a fourth aspect, an embodiment of the present application provides an electronic device, including a processor and a memory, wherein:

[0036] Memory is used to store computer programs;

[0037] The processor is used to load and execute a computer program so that the electronic device executes the machine tool precision compensation method provided in any one of the first aspects above.

[0038] Compared with the prior art, the present invention has the following advantages:

[0039] The embodiments of the present application propose a method, device, storage medium and electronic device for machine tool precision compensation, including: using a probe to obtain the actual three-dimensional coordinates of the center of the ball head when the A and B swing heads of the machine tool are in the actual swing position; according to the three-dimensional coordinates of the reference center of the ball and the three-dimensional coordinates of the actual center of the ball, respectively obtain vector difference information in each coordinate axis direction; wherein, the three-dimensional coordinates of the reference center of the ball are obtained when the A and B swing heads of the machine tool are in the initial position; according to the parameter compensation value of the machine tool and the vector difference information, obtain a target compensation value; wherein, the target compensation value is used to compensate for the precision of the machine tool in the actual swing position. The method of the present application replaces manual inspection with a probe, takes the coordinates of the center of the sphere of the swing head in the initial position as a reference, and uses the coordinates of the center of the sphere of the swing head in the actual swinging position and the reference coordinates to obtain the vector difference information in the direction of each coordinate axis in space, that is, to realize the precision detection of the machine tool, and accurately and efficiently obtain the precision deviation of the machine tool. Since the automated machine tool has the function of self-compensation, the inherent parameter compensation value of the machine tool is combined with the actual obtained precision deviation to avoid the large error caused by using the inherent parameter compensation value alone for compensation, and the target compensation value is obtained comprehensively to achieve more accurate compensation, thereby effectively improving the quality of the machine tool precision compensation. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] FIG1 is a schematic diagram of the structure of an electronic device in a hardware operating environment according to an embodiment of the present application;

[0041] FIG2 is a schematic flow chart of a machine tool precision compensation method provided in an embodiment of the present application;

[0042] FIG3 is a schematic diagram of the functional modules of a machine tool precision compensation device provided in an embodiment of the present application;

[0043] FIG4 is a schematic diagram of an application scenario of a machine tool precision compensation method provided by an embodiment of the present application;

[0044] FIG5 is a schematic diagram showing the principle of obtaining the distance from the rotation center to the spindle end face in the machine tool precision compensation method provided by an embodiment of the present application;

[0045] FIG6 is a schematic diagram of vector difference information in each coordinate axis direction in the machine tool accuracy compensation method provided by an embodiment of the present application;

[0046] Markings in the figure: 101 - processor, 102 - communication bus, 103 - network interface, 104 - user interface, 105 - memory, 1 - ball head, 2 - probe, 3 - probe fixing base, 4 - workbench. DETAILED DESCRIPTION

[0047] It should be understood that the specific embodiments described herein are only used to explain the present application and are not intended to limit the present application.

[0048] The main solution of the embodiments of the present application is: to propose a machine tool precision compensation method, device, storage medium and electronic equipment, including: using a probe to obtain the actual three-dimensional coordinates of the center of the ball head of the machine tool's A and B swing heads in the actual swing position; according to the three-dimensional coordinates of the reference center of the ball and the three-dimensional coordinates of the actual center of the ball, respectively obtain vector difference information in each coordinate axis direction; wherein, the three-dimensional coordinates of the reference center of the ball are obtained when the A and B swing heads of the machine tool are in the initial position; according to the parameter compensation value of the machine tool and the vector difference information, obtain the target compensation value; wherein, the target compensation value is used to compensate for the precision of the machine tool in the actual swing position.

[0049] With the continuous development of science and technology, CNC machine tools, as the mother machines of industry, have been continuously iteratively improved in terms of structural design and functional optimization. The five-axis linkage technology of CNC machine tools has become increasingly mature. RTCP accuracy, as the core precision indicator of high-end CNC machine tools, directly affects the processing quality of CNC machine tools. In recent years, major Chinese OEMs have successively introduced an aluminum alloy processing production line composed of 3-PRS parallel structure CNC machine tools to process large and complex aviation components. This machine tool structure is a horizontal machining center with a BA-type swing head. It uses three linear axes to independently move to simulate the swing angle movement. The center of rotation is the tool center point (RTCP). The parallel structure machine tool is highly recognized by aviation companies for its high efficiency and high-precision processing performance and is well used in the aviation manufacturing industry.

[0050] However, the current RTCP accuracy detection of parallel structure machine tools usually relies on manual detection by professionals using check rods, dial indicators or other similar tools. It is necessary to manually adjust the meter frame and read the dial indicator repeatedly. The overall detection and compensation steps are relatively cumbersome, which is prone to human detection errors and takes a long time to measure. The industry is actively seeking solutions, such as:

[0051] Application number: CN202022963885.9, a five-axis machine tool rapid detection RTCP accuracy device, through three dial indicators respectively set up in the X, Y, and Z directions, can simultaneously detect the vector deviation in the X, Y, and Z directions. However, this detection method is similar to the traditional method, and the accuracy requirements for setting up the dial indicators are too high, and the operation is relatively cumbersome.

[0052] Application number: CN201810699394.2, a five-axis laser processing equipment RTCP precision compensation method, application number: CN202110182396.6, a five-axis CNC machine tool rotary axis structural parameter error compensation method, both technical solutions use corresponding tooling and displacement sensors to detect the axis vector deviation of each axis. This method relies on tooling and displacement sensors for detection. The operation steps are cumbersome, the requirements for debugging personnel are too high, and automated measurement cannot be achieved. It is only suitable for small-scale promotion.

[0053] Therefore, in order to change the current situation of low efficiency of manual inspection and large errors during manual inspection and compensation, and to stabilize the inspection results to improve the quality of compensation accuracy, the present application provides a solution, which uses a probe to replace manual inspection, takes the coordinates of the center of the sphere of the swing head in the initial position as a reference, and uses the coordinates of the center of the sphere of the swing head in the actual swinging position and the reference coordinates to obtain the vector difference information in each coordinate axis direction in space, that is, to realize the precision detection of the machine tool, and accurately and efficiently obtain the precision deviation of the machine tool. Since the automated machine tool has the function of self-compensation, the inherent parameter compensation value of the machine tool is combined with the actual obtained precision deviation to avoid the large error caused by using the inherent parameter compensation value alone for compensation, and the comprehensive target compensation value is obtained to achieve more accurate compensation, which effectively improves the quality of machine tool precision compensation.

[0054] Referring to Figure 1, Figure 1 is a schematic diagram of the structure of an electronic device in the hardware operating environment involved in the embodiment of the present application. The electronic device may include: a processor 101, such as a central processing unit (CPU), a communication bus 102, a user interface 104, a network interface 103, and a memory 105. Among them, the communication bus 102 is used to realize the connection and communication between these components. The user interface 104 may include a display screen (Display), an input unit such as a keyboard (Keyboard), and the user interface 104 may also include a standard wired interface and a wireless interface. The network interface 103 may optionally include a standard wired interface and a wireless interface (such as a wireless fidelity (WIreless-FIdelity, WI-FI) interface). The memory 105 may optionally be a storage device independent of the aforementioned processor 101. The memory 105 may be a high-speed random access memory (RAM) memory, or a stable non-volatile memory (NVM), such as at least one disk memory. The processor 101 may be a general-purpose processor, including a central processing unit, a network processor, etc., or may be a digital signal processor, an application-specific integrated circuit, a field programmable gate array or other programmable logic device, a discrete gate or transistor logic device, or a discrete hardware component.

[0055] Those skilled in the art will appreciate that the structure shown in FIG1 does not limit the electronic device and may include more or fewer components than shown, or combine certain components, or arrange components differently.

[0056] As shown in FIG1 , the memory 105 as a storage medium may include an operating system, a data storage module, a network communication module, a user interface module, and an electronic program.

[0057] In the electronic device shown in Figure 1, the network interface 103 is mainly used for data communication with the network server; the user interface 104 is mainly used for data interaction with the user; the processor 101 and the memory 105 in this application can be set in the electronic device, and the electronic device calls the machine tool precision compensation device stored in the memory 105 through the processor 101, and executes the machine tool precision compensation method provided in the embodiment of this application.

[0058] Referring to FIG2 , based on the hardware device of the aforementioned embodiment, an embodiment of the present application provides a machine tool precision compensation method, which is applied to a machine tool precision compensation device. The device includes a calibration rod and a probe. The calibration rod includes a ball head. The probe is mounted on the workbench of a BA double-swing head five-axis machine tool. The calibration rod is mounted on a tool magazine, comprising the following steps:

[0059] S10: Using the probe, obtain the actual three-dimensional coordinates of the center of the ball head of the machine tool's A and B swing heads when they are in the actual swing position.

[0060] During the specific implementation process, the calibration rod and the probe 2 are commonly used measuring tools in this field. The calibration rod is used to simulate the tool position and is installed on the tool magazine of the machining center. The probe 2 installed on the machine tool workbench 4 can detect the position of the ball head 1 of the calibration rod that matches it. As shown in Figure 4, the probe 2 can be installed on the workbench 4 through the probe fixing base 3. The BA double-swing head machine tool is a machine tool with three linear axes and two rotating axes A and B. The A and B swing heads each control the rotation of the tool in one rotation direction.

[0061] During actual use, the A and B swing heads are connected to the spindle. The actual position refers to the position of the A and B swing heads after they swing to a certain angle when the tool needs to adjust the angle during processing. At this time, the probe can obtain the three-dimensional coordinates of the ball head in the actual position based on the machine tool coordinate system, that is, the actual three-dimensional coordinates of the ball center. The acquisition principle is similar to that of a laser tracker measuring the position coordinates of a target ball.

[0062] S20: Obtain vector difference information in each coordinate axis direction according to the three-dimensional coordinates of the reference sphere center and the three-dimensional coordinates of the actual sphere center; wherein the three-dimensional coordinates of the reference sphere center are obtained when the A and B swing heads of the machine tool are in the initial position.

[0063] In the specific implementation process, the initial position mentioned in the embodiment of the present application is the position where the axis of the calibration rod coincides with the axis of the main shaft and is perpendicular to the workbench 4 in the scenario shown in Figure 4, that is, the position when the swing angles of the A and B swing heads are both zero. The same method can be used to use the probe to measure the three-dimensional coordinates of the ball head 1 in this position based on the machine tool coordinate system, that is, the three-dimensional coordinates of the reference sphere center. The machine tool coordinate system is the coordinate system represented by the XYZ axes in the schematic diagram shown in Figure 6. The vector difference information in the direction of each coordinate axis is the difference between the three-dimensional coordinates of the reference sphere center and the corresponding coordinates of the three-dimensional coordinates of the actual sphere center. As shown in Figure 6, a reference coordinate system X1Y1Z1 is established with the reference sphere center as the origin. Each coordinate axis corresponds to the coordinate axis of the machine tool coordinate system. The angle n is the sphere center, that is, the actual position of the sphere center in the case of a swing angle. The corresponding vector difference is the difference between the corresponding coordinate values, recorded as △X, △Y, △Z, which is the accuracy deviation of the machine tool.

[0064] S30: Obtaining a target compensation value according to the parameter compensation value of the machine tool and the vector difference information; wherein the target compensation value is used to compensate for the accuracy of the machine tool at the actual swing position.

[0065] In the specific implementation process, the parameter compensation value of the machine tool is the compensation value that the CNC machine tool uses its own built-in program to compensate. It is a value with universal adaptability. It can call the program for compensation according to the corresponding parameter compensation value based on the actual processing position. However, in fact, during the processing, the rotation of the tool may affect the position of the tool position, and the inherent parameter compensation of the machine tool cannot compensate for this part of the error. Therefore, the vector difference information is combined with the parameter compensation value of the machine tool to avoid excessive errors caused by one-sided compensation. The deviation between the part position and the tool point is comprehensively considered to accurately compensate for the accuracy of the machine tool at the actual swing position, thereby improving the working effect of the machine tool.

[0066] In this embodiment, a probe is used instead of manual detection, and the coordinates of the center of the sphere of the swing head in the initial position are used as a reference. The coordinates of the center of the sphere of the swing head in the actual swinging position and the reference coordinates are used to obtain the vector difference information in each coordinate axis direction in the space, that is, to realize the precision detection of the machine tool, and accurately and efficiently obtain the precision deviation of the machine tool. Since the automated machine tool has the function of self-compensation, the inherent parameter compensation value of the machine tool is combined with the actual obtained precision deviation to avoid the error caused by using the inherent parameter compensation value alone for compensation. The target compensation value is obtained comprehensively to achieve more accurate compensation. All detection and compensation actions are stored in the internal controller of the machine tool through program compilation and automatically executed in the form of program call, avoiding human intervention and reducing human errors. The precision detection efficiency is higher and more stable, which effectively improves the quality of machine tool precision compensation and ensures the quality of parts processing.

[0067] In one embodiment, before respectively obtaining vector difference information in each coordinate axis direction based on the three-dimensional coordinates of the reference sphere center and the actual sphere center, the machine tool accuracy compensation method further includes:

[0068] Use the probe to obtain the X-axis coordinates and Y-axis coordinates of the reference sphere center of the machine tool's A and B swing heads in the initial position;

[0069] Move the linear axis of the machine tool so that the probe is located at a position with the same coordinates as the X-axis coordinate and the Y-axis coordinate of the center of the reference sphere, and obtain the Z-axis coordinate of the top of the ball head;

[0070] According to the distance from the rotation center to the spindle end face and the Z-axis coordinate of the top of the ball head, the Z-axis coordinate of the reference ball center is obtained;

[0071] The three-dimensional coordinates of the reference sphere center are obtained according to the X-axis coordinate of the reference sphere center, the Y-axis coordinate of the reference sphere center, and the Z-axis coordinate of the reference sphere center.

[0072] In the specific implementation process, since it is in the spatial coordinate system, the three-dimensional coordinates of the reference sphere center include the X, Y, and Z axis coordinates, and in the initial position, the axis of the spindle is perpendicular to the workbench 4, so the probe 2 is located on the axis, and the point coordinates are the same on the X and Y axes, and only differ in the Z axis direction. Therefore, the X-axis coordinate and the Y-axis coordinate of the reference sphere center are obtained first, and then the linear axis of the mobile machine tool is adjusted so that the position of the probe 2 comes to the measured reference sphere center position to measure the Z coordinate of the ball head. Since the probe 2 and the ball head 1 both have a certain volume, they cannot be equivalently regarded as points, because the top Z coordinate of the ball head 1 can only be measured by contact. After measurement, according to the line segment relationship, the absolute value of the Z-axis coordinate of the reference sphere center is equal to the measured absolute value of the Z coordinate of the top of the ball head minus the distance from the rotation center to the spindle end face, the ball head radius, and the probe radius, and the Z-axis coordinate of the reference sphere center can be obtained. In this way, the coordinates of the reference sphere center on each coordinate axis have been obtained, and the three-dimensional coordinates of the reference sphere center can be obtained.

[0073] In one embodiment, before obtaining the Z-axis coordinate of the reference sphere center based on the distance from the rotation center to the spindle end face and the Z-axis coordinate of the top of the ball head, the machine tool precision compensation method further includes:

[0074] Obtaining first and second spherical center coordinates of the ball head within a swing range of the swing head of the machine tool and at a swing position symmetrical to an initial position of the swing head;

[0075] The distance from the rotation center to the spindle end face is obtained according to the length of the calibration rod, the simple pendulum angle of the pendulum head, the coordinates of the first sphere center, and the coordinates of the second sphere center.

[0076] During the specific implementation process, the distance from the rotation center to the spindle end face is verified to improve the accuracy of the data, as shown in Figure a in Figure 5. Based on any one swing head, it swings symmetrically relative to the initial position. The rotation center point A and the center of the ball at the two swinging positions form an isosceles triangle. The center points of the spindle end faces of the two swings are B and B' respectively. The extracted triangle is shown in Figure b in Figure 5. When the swing angle can be manually controlled, the base of the virtual isosceles triangle can be obtained according to the coordinate difference of the center of the ball in the swing direction under the two swings, and the waist length is the sum of the distance from the rotation center to the spindle end face and the length of the calibration rod. If the single swing angle and the length of the side opposite to the angle are known, in the right triangle, the length of the hypotenuse can be obtained according to its sine value, and the distance from the rotation center to the spindle end face is obtained by subtracting the known length of the calibration rod from the length of the hypotenuse. As shown in Figure 5, the single swing angle is 30 degrees, and the virtual triangle formed is an equilateral triangle. As a special triangle with three equal sides, the difference in coordinates can be used to obtain the length of a single side. Then the sum of the distance from the rotation center to the end face of the main shaft and the length of the calibration rod has been obtained. At this time, there is no need to use angles for calculation.

[0077] In one embodiment, obtaining the distance from the rotation center to the spindle end face according to the length of the calibration rod, the simple pendulum angle of the pendulum head, the first sphere center coordinates, and the second sphere center coordinates includes:

[0078] According to the length of the calibration rod, the simple pendulum angle of the pendulum head, the coordinates of the first sphere center and the second sphere center, the distance from the rotation center to the spindle end face within the swing range of the pendulum head is calculated, and the distance from the first rotation center to the spindle end face and the distance from the second rotation center to the spindle end face are obtained;

[0079] The distance from the rotation center to the spindle end face is obtained according to the average value of the distance from the first rotation center to the spindle end face and the distance from the second rotation center to the spindle end face.

[0080] During the specific implementation process, since it is a double-swing head machine tool, it can swing in two directions. In order to improve the detection accuracy, comprehensive multi-angle data is used for verification. Specifically, according to the same method as mentioned above, the distance data from the two rotation centers to the spindle end face are obtained based on the two swing angles, that is, the distance from the first rotation center to the spindle end face and the distance from the second rotation center to the spindle end face. By averaging the two data, a more accurate distance from the rotation center to the spindle end face is obtained, further improving the accuracy of precision detection and compensation.

[0081] In one embodiment, the three-dimensional coordinates of the actual center of the ball head of the machine tool A and B swing heads are obtained by using a probe, including:

[0082] Using the probe and the multi-layer roundness coordinate calculation method, the actual three-dimensional coordinates of the ball center of the machine tool's A and B swing heads in the actual swing position are obtained.

[0083] In the specific implementation process, in order to reduce the impact of local precision errors on the surface of the ball head 1, the embodiment of the present application adopts a multi-layer roundness coordinate calculation method to obtain the three-dimensional coordinates of the actual center of the ball head. The multi-layer roundness calculation method uses the same center to measure the roundness coordinates on circles of different radii to gradually approximate the actual sphere to be measured. Specifically:

[0084] Using the probe and the multi-layer roundness coordinate calculation method, the actual three-dimensional coordinates of the ball center of the machine tool's A and B swing heads are obtained when they are in the actual swing position, including:

[0085] Use the probe to obtain the multi-layer roundness coordinates on the ball head of the machine tool's A and B swing heads at the actual swing position;

[0086] According to the average value of each layer of roundness coordinates in the multi-layer roundness coordinates on the ball head, several single-layer roundness coordinates are obtained;

[0087] The actual three-dimensional coordinates of the ball center are obtained based on the average value of several single-layer roundness coordinates.

[0088] In the specific implementation process, the roundness coordinates of each layer are obtained by approximating the roundness coordinates on the sphere measured by the ball head along the positive and negative directions of the X and Y axes according to the swing position, and then calculating the precise three-dimensional coordinates of the actual center of the sphere based on the average values ​​of the coordinates in the X and Y axes directions. However, it should be noted that since the multi-layer roundness coordinate calculation method only focuses on the X and Y axis data on the sphere, the X and Y axis coordinates used to obtain the actual three-dimensional coordinates of the center of the sphere in this embodiment, the Z axis coordinate of the actual three-dimensional coordinates of the center of the sphere can be obtained according to the method of the aforementioned embodiment.

[0089] In one embodiment, after obtaining vector difference information in each coordinate axis direction based on the three-dimensional coordinates of the reference sphere center and the actual sphere center, the machine tool accuracy compensation method further includes:

[0090] It is determined whether the vector difference information in each coordinate axis direction is greater than a preset precision error threshold. If the result of the determination is yes, a machine tool alarm process is executed.

[0091] During the specific implementation process, since the machine tool faces problems such as overtravel in actual operation, an excessively large vector difference indicates that a major fault has occurred in the machine tool's accuracy. The correction based on the vector difference information may not be completed due to swing angle, linear axis motion overtravel, etc. In this case, it is necessary to set a threshold to ensure safety, that is, a preset accuracy error threshold. If the vector difference information exceeds the threshold, an alarm is required so that relevant personnel can perform maintenance. If the vector difference information does not exceed the threshold, automatic correction can be performed. The correction can be based on a pre-generated accuracy compensation table. The compensation table is generated based on the swing angle degree and its corresponding parameter compensation value and the vector difference. That is, each swing angle degree corresponds to a clear target compensation value. The accuracy compensation of the machine tool can be achieved by simply calling the machine tool's internal program.

[0092] With reference to Figures 4 to 6, the present application is further described in one embodiment:

[0093] Install the probe fixed base 3 on the workbench 4, install the probe 2 on the probe fixed base 3, install the calibration rod in the tool magazine, execute the compiled measurement program to drive the probe 2 to measure the ball head 1, move the swing angle to A30 / B0, approach the ball head 1 along the positive and negative directions of the X and Y axes to measure the multi-layer roundness coordinates on the sphere, then the coordinates of the first circle are [(X1, X2), (Y1, Y2)], the second circle are [(X3, X4), (Y3, Y4)], and so on, the nth circle is [(Xn, Xn+1), (Yn, Yn+1)], and each The coordinates of each circle are averaged. For example, the X-axis coordinate of the first circle is the average value of X1 and X2, Xa1, and the Y-axis coordinate is the average value of Y1 and Y2, Ya1. That is, the center coordinates of circle 1 are (Xa1, Ya1). Similarly, the center coordinates of the nth circle are (Xan, Yan). The coordinate values ​​of all circles are averaged to obtain the actual center coordinates, that is, the actual center X-axis coordinate CENT1_X1 = (Xa1+Xa2+…+Xan) / n, and the actual center Y-axis coordinate CENT1_Y1 = (Ya1+Ya2+…+Yan) / n. According to the same principle, move the swing angle to A-30 / B0 and calculate the actual center coordinates CENT1_X2 and CENT1_Y2 at that position.

[0094] Then move the swing angle A from 30° to -30°, and use the equilateral triangle to calculate the distance from the first rotation center to the spindle end face under the swing angle A: λ1 = |CENT_Y1-CENT_Y2|-L, where L is the length of the calibration rod; under the swing angle B, the distance from the second rotation center to the spindle end face: λ2 = |CENT_X3-CENT_X4|-L, and then average the two to obtain the distance from the rotation center to the spindle end face: λ = (λ1+λ2) / 2.

[0095] Move the swing angle to A0 / B0, and measure the X and Y axis coordinates of the reference sphere center in the same way as mentioned above, that is, BALL_X and BALL_Y. Move the linear axis of the machine tool to move the probe 2 to the X and Y axis coordinates at BALL_X and BALL_Y, and measure the Z axis coordinate BALL_Z0 of the top of the ball head. Then, based on the known ball head radius R1, probe radius R2, and the distance λ from the rotation center to the spindle end face obtained above, calculate the Z axis coordinate of the reference sphere center BALL_Z = BALL_Z0-R1-R2-λ, that is, the three-dimensional coordinates of the reference sphere center are BALL_X, BALL_Y, and BALL_Z.

[0096] According to the swing angle set in the matrix list, the sphere center coordinates BALL_Xn, BALL_Yn, and BALL_Zn at the A / B swing angle and composite angle are detected in turn. By subtracting the three-dimensional coordinates of the reference sphere center at A0 / B0, the change in coordinates at each swing angle is obtained. This change is the vector difference in space when the machine tool moves, specifically: △X1=BALL_X1-BALL_X, △Y1=BALL_Y1-BALL_Y, △Z1=BALL_Z1-BALL_Z...△Xn=BALL_Xn-BALL_X, △Yn=BALL_Yn-BALL_Y, △Zn=BALL_Zn-BALL_Z.

[0097] Read the machine tool parameter compensation value:

[0098] X11=COMP_VALUE[1,0],Y11=COMP_VALUE[1,1],Z11=COMP_VALUE[1,2],X11,Y11,Z11 respectively refer to the compensation values ​​in the three directions when the machine tool is at the angle corresponding to 1. Then the compensation value corresponding to the angle corresponding to n can be expressed as: Xn1=COMP_VALUE[n,0],Yn1=COMP_VALUE[n,1],Zn1=COMP_VALUE[n,2]. The new compensation value is calculated by the vector difference between the read compensation value and the measured value. The new compensation value, that is, the target compensation value is:

[0099] COMP_VALUE[1,0]=X11+△X1,

[0100] COMP_VALUE[1,1]=Y11+△Y1,

[0101] COMP_VALUE[1,2]=Z11+△Z1……

[0102] COMP_VALUE[n,0]=Xn1+ΔXn,

[0103] COMP_VALUE[n,1]=Yn1+△Yn,

[0104] COMP_VALUE[n,2]=Zn1+ΔZn;

[0105] The calculated results generate an accuracy compensation table and set the accuracy error threshold XM. When △Xn, △Yn, △Zn ≤ XM, the program automatically calls the accuracy compensation table and performs accuracy compensation; when △Xn, △Yn, △Zn>XM, the corresponding alarm is output, indicating that professional maintenance personnel are needed to handle it.

[0106] Referring to FIG3 , based on the same inventive concept as in the aforementioned embodiment, the present embodiment further provides a machine tool precision compensation device, the device comprising a calibration rod and a probe, the calibration rod comprising a ball head, the probe being mounted on a workbench of a BA double-swing head five-axis machine tool, the calibration rod being mounted on a tool magazine, and the device further comprising:

[0107] The measuring module is used to obtain the actual three-dimensional coordinates of the center of the ball head of the machine tool's A and B swing heads when they are in the actual swing position using a probe;

[0108] A vector difference acquisition module is used to obtain vector difference information in each coordinate axis direction based on the three-dimensional coordinates of the reference sphere center and the three-dimensional coordinates of the actual sphere center. The three-dimensional coordinates of the reference sphere center are obtained when the A and B swing heads of the machine tool are in their initial positions.

[0109] The compensation module is used to obtain a target compensation value based on the parameter compensation value and vector difference information of the machine tool; wherein the target compensation value is used to compensate for the accuracy of the machine tool under the actual swing position.

[0110] Those skilled in the art should understand that the division of the various modules in the embodiment is merely a division of logical functions, and in actual application, they can be fully or partially integrated into one or more actual carriers, and these modules can all be implemented in the form of software called through the processing unit, or all in the form of hardware, or in the form of a combination of software and hardware. It should be noted that the modules in the machine tool precision compensation device in this embodiment correspond one-to-one to the steps in the machine tool precision compensation method in the aforementioned embodiment. Therefore, the specific implementation of this embodiment can refer to the implementation of the aforementioned machine tool precision compensation method, and will not be repeated here.

[0111] Based on the same inventive concept as in the aforementioned embodiment, an embodiment of the present application further provides a computer-readable storage medium storing a computer program. When the computer program is loaded and executed by a processor, the machine tool precision compensation method provided in the embodiment of the present application is implemented.

[0112] In addition, based on the same inventive concept as in the above embodiment, an embodiment of the present application further provides an electronic device, comprising at least a processor and a memory, wherein:

[0113] Memory is used to store computer programs;

[0114] The processor is used to load and execute a computer program so that the electronic device executes the machine tool precision compensation method provided in the embodiment of the present application.

[0115] In some embodiments, the computer-readable storage medium may be a memory device such as FRAM, ROM, PROM, EPROM, EEPROM, flash memory, magnetic surface mount memory, optical disk, or CD-ROM; or various devices including any one or any combination of the above memories. The computer may be various computing devices including smart terminals and servers.

[0116] In some embodiments, executable instructions may be in the form of a program, software, software module, script, or code, written in any form of programming language (including compiled or interpreted languages, or declarative or procedural languages), and may be deployed in any form, including as a stand-alone program or as a module, component, subroutine, or other unit suitable for use in a computing environment.

[0117] As an example, executable instructions may, but need not, correspond to a file in a file system, may be stored as part of a file that stores other programs or data, such as in one or more scripts in a HyperText Markup Language (HTML) document, in a single file dedicated to the program in question, or in multiple coordinating files (e.g., files storing one or more modules, subroutines, or code portions).

[0118] By way of example, executable instructions may be deployed to be executed on one computing device, or on multiple computing devices at one site, or on multiple computing devices distributed across multiple sites and interconnected by a communication network.

[0119] It should be noted that, in this document, the terms "comprises," "includes," or any other variations thereof are intended to encompass non-exclusive inclusion, such that a process, method, article, or system comprising a series of elements includes not only those elements but also other elements not explicitly listed, or elements inherent to such process, method, article, or system. In the absence of further limitations, an element defined by the phrase "comprising a ..." does not exclude the presence of other identical elements in the process, method, article, or system comprising the element.

[0120] The above sequence of the embodiments of the present application is for description only and does not represent the superiority or inferiority of the embodiments.

[0121] Through the description of the above implementation methods, those skilled in the art can clearly understand that the above-mentioned embodiment methods can be implemented by means of software plus the necessary general hardware platform, and of course can also be implemented by hardware, but in many cases the former is a better implementation method. Based on this understanding, the technical solution of the present application, or the part that contributes to the prior art, can be embodied in the form of a software product, which is stored in a storage medium (such as read-only memory / random access memory, magnetic disk, optical disk), and includes a number of instructions for enabling a multimedia terminal device (which can be a mobile phone, computer, television receiver, or network device, etc.) to execute the methods of each embodiment of the present application.

[0122] In summary, the present application provides a machine tool precision compensation method, device, storage medium and electronic equipment, which replaces manual detection with a probe, takes the spherical center coordinates of the swing head in the initial position as a reference, and uses the spherical center coordinates of the swing head in the actual swinging position and the reference coordinates to obtain vector difference information in each coordinate axis direction in space, that is, to realize the precision detection of the machine tool, and accurately and efficiently obtain the precision deviation of the machine tool. Since the automated machine tool has the function of self-compensation, the inherent parameter compensation value of the machine tool is combined with the actual obtained precision deviation to avoid the error caused by using the inherent parameter compensation value alone for compensation. The target compensation value is obtained comprehensively to achieve more accurate compensation. All detection and compensation actions are stored in the internal controller of the machine tool through program compilation and automatically executed in the form of program calls, avoiding manual intervention and reducing human errors. The precision detection efficiency is higher and more stable, which effectively improves the quality of machine tool precision compensation and ensures the quality of parts processing.

[0123] The above description is only a preferred embodiment of the present application and is not intended to limit the present application. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present application should be included in the scope of protection of the present application.

Claims

1. A machine tool accuracy compensation method, characterized in that: Applied to a machine tool precision compensation device, the device includes a calibration rod and a probe, the calibration rod includes a ball head, the probe is installed on a workbench of a BA double-swing head five-axis machine tool, and the calibration rod is installed on a tool magazine, including the following steps: Using the probe, the actual three-dimensional coordinates of the center of the ball head of the machine tool A and B swing heads are obtained when the swing heads are in actual swing positions; According to the three-dimensional coordinates of the reference sphere center and the three-dimensional coordinates of the actual sphere center, vector difference information in each coordinate axis direction is obtained respectively; wherein the three-dimensional coordinates of the reference sphere center are obtained when the A and B swing heads of the machine tool are in the initial position; A target compensation value is obtained according to the parameter compensation value of the machine tool and the vector difference information; wherein the target compensation value is used to compensate for the accuracy of the machine tool at the actual swing position.

2. The machine tool accuracy compensation method according to claim 1, characterized in that: Before respectively obtaining the vector difference information in each coordinate axis direction according to the reference spherical center three-dimensional coordinates and the actual spherical center three-dimensional coordinates, the machine tool accuracy compensation method further includes: Using the probe, obtaining the X-axis coordinate of the center of the reference sphere and the Y-axis coordinate of the center of the reference sphere when the A and B swing heads of the machine tool are in the initial position; Moving the linear axis of the machine tool so that the probe is located at a position having the same coordinates as the X-axis coordinate of the reference sphere center and the Y-axis coordinate of the reference sphere center, and obtaining the Z-axis coordinate of the top of the ball head; Obtain the Z-axis coordinate of the center of the reference ball according to the distance from the rotation center to the spindle end face and the Z-axis coordinate of the top of the ball head; The three-dimensional coordinates of the reference sphere center are obtained according to the X-axis coordinate of the reference sphere center, the Y-axis coordinate of the reference sphere center and the Z-axis coordinate of the reference sphere center.

3. The machine tool accuracy compensation method according to claim 2, characterized in that: Before obtaining the Z-axis coordinate of the reference sphere center according to the distance from the rotation center to the spindle end face and the Z-axis coordinate of the top of the ball head, the machine tool accuracy compensation method further includes: Obtaining first spherical center coordinates and second spherical center coordinates of the ball head within a swing range of the swing head of the machine tool and at a swing position symmetrical to an initial position of the swing head; The distance from the rotation center to the spindle end face is obtained according to the length of the calibration rod, the simple pendulum angle of the pendulum head, the first spherical center coordinates and the second spherical center coordinates.

4. The machine tool accuracy compensation method according to claim 3, characterized in that: The step of obtaining the distance from the rotation center to the spindle end face according to the length of the calibration rod, the single pendulum angle of the pendulum head, the first spherical center coordinates, and the second spherical center coordinates comprises: According to the length of the calibration rod, the single pendulum angle of the pendulum head, the first spherical center coordinates and the second spherical center coordinates, the distance from the rotation center to the spindle end face within the swing range of the pendulum head is calculated respectively, and the distance from the first rotation center to the spindle end face and the distance from the second rotation center to the spindle end face are obtained; The distance from the rotation center to the spindle end face is obtained according to an average value of the distance from the first rotation center to the spindle end face and the distance from the second rotation center to the spindle end face.

5. The machine tool accuracy compensation method according to claim 1, characterized in that: The method of using the probe to obtain the actual three-dimensional coordinates of the center of the ball head of the machine tool when the A and B swing heads are in the actual swing position includes: The probe is used to obtain the actual three-dimensional coordinates of the center of the ball head when the A and B swing heads of the machine tool are in the actual swing position by adopting a multi-layer roundness coordinate calculation method.

6. The machine tool accuracy compensation method according to claim 5, characterized in that: The method of using the probe and adopting a multi-layer roundness coordinate calculation method to obtain the actual three-dimensional coordinates of the center of the ball head when the A and B swing heads of the machine tool are in the actual swing position includes: Using the probe, obtaining the multi-layer roundness coordinates on the ball head when the A and B swing heads of the machine tool are in actual swing positions; Obtaining a plurality of single-layer roundness coordinates according to an average value of each layer of roundness coordinates among the multiple layers of roundness coordinates on the ball head; The actual 3D coordinate of the ball center of the ball head is obtained based on the average value of the single-layer roundness coordinates. Mark.

7. The machine tool accuracy compensation method according to claim 1, characterized in that: After respectively obtaining the vector difference information in each coordinate axis direction according to the reference spherical center three-dimensional coordinates and the actual spherical center three-dimensional coordinates, the machine tool accuracy compensation method further includes: It is determined whether the vector difference information in each coordinate axis direction is greater than a preset precision error threshold, and if the result of the determination is yes, a machine tool alarm process is executed.

8. A machine tool precision compensation device, characterized in that: The device comprises a calibration rod and a probe, wherein the calibration rod comprises a ball head, the probe is mounted on a workbench of a BA double-swing head five-axis machine tool, and the calibration rod is mounted on a tool magazine. The device further comprises: A measuring module, the measuring module is used to obtain the actual three-dimensional coordinates of the center of the ball head when the A and B swing heads of the machine tool are in actual swing positions by using the probe; A vector difference obtaining module, the vector difference obtaining module is used to obtain vector difference information in each coordinate axis direction according to the three-dimensional coordinates of the reference sphere center and the three-dimensional coordinates of the actual sphere center; wherein the three-dimensional coordinates of the reference sphere center are obtained when the A and B swing heads of the machine tool are in the initial position; A compensation module is used to obtain a target compensation value according to the parameter compensation value of the machine tool and the vector difference information; wherein the target compensation value is used to compensate for the accuracy of the machine tool at an actual swing position.

9. A computer-readable storage medium storing a computer program, characterized in that: When the computer program is loaded and executed by the processor, the machine tool precision compensation method according to any one of claims 1 to 7 is implemented.

10. An electronic device, characterized in that: comprising a processor and a memory, wherein: The memory is used to store computer programs; The processor is used to load and execute the computer program so that the electronic device executes the machine tool precision compensation method according to any one of claims 1 to 7.

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