Offline programming method for full-six-axis CNC rough machining and polishing device

Abstract

An offline programming method for a full-six-axis CNC rough machining and polishing device. The method comprises: importing a three-dimensional model of a product into CAM software, interactively setting information of a workpiece coordinate system and a tool coordinate system of the three-dimensional model, selecting a route on which an operation is required, and generating path data; importing the three-dimensional model and the path data into offline programming software, and performing simplification processing on the path data; implementing an overall offset function, a single-point offset function and posture adjustment of the path data in the tool coordinate system; implementing simulation running of a tool and collision detection; on the basis of the path data and tool data, generating an NC program conforming to a program standard; and a six-axis device creating the workpiece coordinate system on the product; and monitoring a running state. Therefore, problems such as the polishing programming efficiency of products of complex structures being low, the follow-up reading, modifying and positioning being time-consuming due to the fact that CAM software exports excessive path data, and there being a certain difference between a model generation path and an actual device running path are solved.

Description

An offline programming method for full six-axis CNC rough machining and grinding equipment Technical Field

[0001] The present invention relates to the field of casting technology, in particular to an off-line programming method for full six-axis CNC rough machining and grinding equipment. Background Art

[0002] Casting is an important basic process in the machinery industry. The development of equipment manufacturing, automobile industry, rail transportation, and aerospace is inseparable from this basic industry. However, due to the constraints of production equipment and processes, and in order to meet the requirements of product appearance and surface quality, burr removal and surface grinding have become one of the inevitable processes in the subsequent processing of cast products. Traditional cleaning and polishing operations mainly rely on manual labor. Not only are the labor intensity high, the working environment is harsh, and long-term work is prone to occupational hazards, but there are also serious safety hazards. The finished product also depends on the skill level of the employees, making it difficult to ensure quality consistency. The polishing equipment currently on the market has low efficiency in programming and debugging for polishing products with complex structures. It mainly relies on manual point-to-point teaching programming. The use of traditional CAM software to export processing trajectory data points is too excessive, and the generated program file is too large, making the program reading cumbersome. In addition, it is difficult to make effective positioning modifications when the subsequent operation trajectory needs to be adjusted according to the product. There is a certain gap between the trajectory generated by the model and the actual operation trajectory of the equipment.

[0003] Based on the above technical problems, the applicant proposed the technical solution of this application. Summary of the Invention

[0004] In view of the above-mentioned defects of the prior art, the present invention provides an offline programming method for full six-axis CNC rough machining and grinding equipment, which solves the problem of low grinding programming efficiency of complex structure products, solves the problem of excessive trajectory data exported by CAM software and time-consuming subsequent reading, modification and positioning, and solves the problem of a certain gap between the model-generated trajectory and the actual equipment operation trajectory. Under the premise of not affecting the machining and grinding effect, the number of data points on the trajectory is reduced by half, and the debugging time of new products is shortened by half.

[0005] In order to achieve the above object, the present invention discloses an off-line programming method for a full six-axis CNC rough machining and grinding equipment, comprising the following steps:

[0006] (1) Import the product 3D model into the CAM software, interactively set its workpiece coordinate system and tool coordinate system information, select the path to be operated, and generate trajectory data;

[0007] (2) Import the 3D model and trajectory data into the offline programming software and simplify the trajectory data through the fitting algorithm;

[0008] (3) Realize the overall offset function of trajectory data in the tool coordinate system, the single-point or multi-point offset function and the re-matching generation of the arc trajectory after offset, as well as the single-point or multi-point posture adjustment;

[0009] (4) Realize the simulation operation of the tool and collision detection;

[0010] (5) Generate an NC program that meets the program standards of the full six-axis CNC rough machining and grinding equipment based on the trajectory data and tool data, and upload it to the equipment controller;

[0011] (6) The full six-axis CNC rough machining and grinding equipment sets the workpiece coordinates according to the actual status of the product and starts running the program file;

[0012] (7) Offline programming software monitors the equipment operating status in real time.

[0013] Preferably, the simplification processing of the trajectory data by using a fitting algorithm includes:

[0014] Performing field analysis on the trajectory data, extracting field data and performing coordinate transformation to obtain trajectory segment information in a workpiece coordinate system, wherein the field data at least includes an instruction mode, a point position, coordinates, a normal system, and a speed;

[0015] Calculating the curvature value of each point according to the trajectory segment information, deleting abnormal points according to the threshold judgment result of the curvature value of each point, and retaining the curvature value of normal points;

[0016] According to the inner and outer threshold controls set in the tool feed direction, as well as the relative angle change threshold control between the tool normal and the tool feed direction, global adaptive segmented straight line fitting and spatial arc fitting are performed on the normal points in the trajectory segment information to achieve simplified processing of the trajectory data.

[0017] Preferably, the inner and outer threshold value control set in the tool feed direction includes the following steps:

[0018] Step 3.1, create an empty point set S1;

[0019] Step 3.2, in the trajectory area composed of short line segments, take any point as the first starting point and add it to the set S1;

[0020] Step 3.3: along the trajectory direction of the first starting point, take a point that moves forward as the next point, and determine whether the curvature of the next point is similar to that of the previous point. If the curvatures of the two points are similar, add the next point to set S1;

[0021] Step 3.4, use a straight line segment or an arc segment on the tool plane to fit the points in set S1, calculate the error value between the midpoint of set S1 and the fitted line segment, if the error value does not exceed the preset internal and external thresholds, continue to move forward along the trajectory direction, return to step 3.3 and repeat, continue to add points to set S1, if the error value exceeds the internal and external thresholds, stop fitting, delete the last point in set S1, and use the line segment fitted by the points in set S1 as the new trajectory to replace the short line segment where the midpoint of set S1 is located.

[0022] Preferably, when the path to be operated is a flat milling path, the inner and outer thresholds are set to 50% to 60% of the tool radius length; when the path to be operated is a side milling path and the path plane is parallel to the tool direction, the inner and outer thresholds are set to 50% to 60% of the blade length; when the path to be operated is a side milling path and the path plane is perpendicular to the tool direction, the inner and outer thresholds are set to the residual error value allowed for grinding.

[0023] Preferably, the control of the relative angle change threshold between the tool normal and the tool feed direction comprises the following steps:

[0024] Step 5.1: When it is detected that consecutive points in the trajectory segment information are on the same plane and the tool height in the Z direction varies, the consecutive points are recorded as point set S2, and the angles between the tool normal and the feed direction for all points in point set S2 are calculated;

[0025] Step 5.2: select any point in the point set S2 as the second starting point;

[0026] Step 5.3: Take other points in point set S2 as comparison points and compare the angle change rate between the second starting point and the comparison point. The angle change rate is the ratio of the difference between the two angles to the distance between the two points.

[0027] Step 5.4: If the angle change rate is greater than the change threshold, use the comparison point as the second starting point and repeat step 5.3 until all points in point set S2 are traversed;

[0028] Step 5.5: If the angle change rate is not greater than the change threshold, delete the comparison point from the point set S2, return to step 5.3 to select the next point as the comparison point, and continue until all points in the point set S2 are traversed.

[0029] Preferably, the least square method is used to control errors during the straight line fitting and the spatial arc fitting, so as to transform short line segments into long straight line segments or spatial arc segments.

[0030] Preferably, the CAM software is specifically MasterCam software, and the trajectory data is an NCI file exported from the MasterCam software.

[0031] Preferably, before implementing the simulation operation of the tool, the equipment, tool, product and program files are loaded into the offline programming software.

[0032] Preferably, the method is applied to a full six-axis CNC rough machining equipment, which includes a machine tool installed on a base, the machine tool is provided with a linear motion axis, a rotary motion axis, a rotary cutter head and a workpiece mounting disk, the linear motion axis includes an X-axis, a Y-axis and a Z-axis, the rotary motion axis includes an A-axis, a B-axis and a C-axis, the X-axis is located on the machine tool, the Y-axis is located on the base, the Z-axis is located in front of the X-axis, the A-axis is located above the Y-axis, the B-axis is located in front of the Z-axis, the C-axis is located below the A-axis, the workpiece mounting disk is located on the C-axis, and the rotary cutter head is located on the B-axis.

[0033] Preferably, the X-axis is provided with an X-axis screw rod, and the end of the X-axis screw rod is provided with an X-axis motor; the Y-axis is provided with a Y-axis screw rod, and the end of the Y-axis screw rod is provided with a Y-axis motor; the Z-axis is provided with a Z-axis screw rod, and the end of the Z-axis screw rod is provided with a Z-axis motor.

[0034] Compared with the prior art, the present invention has the following beneficial effects:

[0035] 1. The offline programming method of the full six-axis CNC rough machining and grinding equipment provided by the present invention sets the workpiece coordinate system and the tool coordinate system through trajectory visualization interactive generation software, thereby improving the grinding programming efficiency of complex structure products.

[0036] 2. The offline programming method for full six-axis CNC rough machining and grinding equipment provided by the present invention simplifies the trajectory data with one click through threshold fitting, avoiding the time-consuming and labor-intensive problem of viewing, modifying and positioning caused by excessive trajectory data exported by CAM software. The simplified trajectory data only needs overall adjustment and local fine-tuning, solving the problem of the gap between the simulated generated trajectory and the actual equipment operation trajectory.

[0037] 3. The offline programming method of the full six-axis CNC rough machining and grinding equipment provided by the present invention avoids the possibility of collision between the tool and the product during actual operation by simulating the operation of the tool.

[0038] The concept, specific structure and technical effects of the present invention will be further described below in conjunction with the accompanying drawings to fully understand the purpose, characteristics and effects of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] FIG1 is a flow chart of an off-line programming method for a full six-axis CNC rough machining and grinding device according to the present invention.

[0040] FIG2 is a front structural schematic diagram of the full six-axis CNC rough machining and grinding equipment used in the method of the present invention.

[0041] FIG3 is a schematic side view of the structure of the full six-axis CNC rough machining and grinding equipment used in the method of the present invention.

[0042] FIG4 is a schematic diagram of kinematic forward and inverse solution transformation used in the method of the present invention. DETAILED DESCRIPTION

[0043] In order to make the technical means, creative features, objectives and effects of the invention easier to understand, the invention is further described below with reference to specific diagrams. However, the invention is not limited to the following implementation cases.

[0044] It should be noted that the structures, proportions, sizes, etc. illustrated in the drawings in this specification are only used to match the contents disclosed in the specification so that people familiar with this technology can understand and read them. They are not used to limit the conditions under which the present invention can be implemented. Therefore, they have no substantive technical significance. Any modification of the structure, change in the proportion relationship or adjustment of the size should still fall within the scope of the technical content disclosed in the present invention without affecting the efficacy and purpose that can be achieved by the present invention.

[0045] The present invention discloses an off-line programming method for a full six-axis CNC rough machining and grinding device, comprising the following steps:

[0046] Step S1: Import the product 3D model into the CAM software, interactively set its workpiece coordinate system and tool coordinate system information, select the path to be operated, and generate trajectory data.

[0047] Specifically, the product 3D model is imported into the CAM software, and its workpiece coordinate system (WorkCoord), tool coordinate system (ToolCoord) and other information are interactively set. The path to be operated is selected to generate trajectory data (PathList). This can take advantage of the editing advantages of CAM, but is not limited to a specific CAM software and can support trajectory data exported from multiple CAM software. In this embodiment, the CAM software is specifically MasterCam software, and the trajectory data is an NCI file exported from MasterCam software.

[0048] Step S2: import the three-dimensional model and trajectory data into the offline programming software, and simplify the trajectory data through the fitting algorithm.

[0049] Specifically, the simplification process of the trajectory data by the fitting algorithm includes the following steps:

[0050] Step 2.1, perform field analysis on the trajectory data, extract field data and perform coordinate transformation to obtain trajectory segment information in the workpiece coordinate system, wherein the field data at least includes instruction mode, point position, coordinates, normal system, and speed.

[0051] Specifically, field analysis is performed on the trajectory data produced by CAM software, and field data (command mode, point position, coordinates, normal system, speed, tool, etc.) is extracted. The coordinates are transformed into trajectory segment information (fast, straight line, arc, etc.) in the specified workpiece coordinate system, and these trajectory segment information and process information are automatically converted into standard G-code command files, realizing the display and editing operations (creating new commands, modifying commands, deleting commands, copying and pasting commands, etc.) of G-code command files and trajectories, as well as the import and export functions of files.

[0052] Step 2.2: Calculate the curvature value of each point based on the trajectory segment information, delete abnormal points based on the threshold judgment result of the curvature value of each point, and retain the curvature value of normal points.

[0053] Specifically, the curvature value of each point is calculated through continuous discrete points. For example, the coordinates of three discrete points are: (x 1, y1),(x 2, y2),(x 3, y3), the calculated coordinate is (x 2, The curvature value of the point y2) is obtained as follows:

[0054] Assuming the curve parameter t, we have

[0055] The x represents the x in three discrete points 1, x 2, The x-axis coordinate value of the curve obtained by fitting the quadratic polynomial of the value of x3, and y represents the y value of the three discrete points. 1, y 2, The value of y3 is the y-axis coordinate value of the curve obtained by fitting the quadratic polynomial, a1, a2, and a3 respectively represent the parameters of the x-axis coordinate for the quadratic polynomial fitting, and b1, b2, and b3 respectively represent the parameters of the y-axis coordinate for the quadratic polynomial fitting.

[0056] remember:

[0057] Among them, t a represents (x 1, y1),(x 2, y2) The distance between two points, t b represents (x 2, y2),(x 3,y3) The distance between two points.

[0058] The following conditions are met:

[0059] Then we have:

[0060] Therefore, by solving the inverse matrix, we can solve (a1, a2, a3) and (b1, b2, b3), so the point (x 2, The curvature value k at y2) is:

[0061] After calculating the curvature value of each point according to the above method, a reasonable curvature threshold range is set according to the actual situation to judge each point as an outlier. Points whose curvature values ​​exceed the curvature threshold range are regarded as outliers. These outliers in the trajectory segment information are deleted, so that only normal points are retained in the trajectory segment information.

[0062] In step 2.3, based on the inner and outer threshold controls set in the tool feed direction, as well as the relative angle change threshold control between the tool normal and the tool feed direction, global adaptive segmented straight line fitting and spatial arc fitting are performed on the normal points in the trajectory segment information to achieve simplified processing of the trajectory data.

[0063] Specifically, the least square method is used to control errors during the straight line fitting and the spatial arc fitting, so as to transform short line segments into long straight lines or spatial arc segments.

[0064] The inner and outer threshold control set in the tool feed direction includes the following steps:

[0065] Step 3.1, create an empty point set S1;

[0066] Step 3.2, in the trajectory area composed of short line segments, take any point as the first starting point and add it to the set S1;

[0067] Step 3.3: along the trajectory direction of the first starting point, take a point that moves forward as the next point, and determine whether the curvature of the next point is similar to that of the previous point. If the curvatures of the two points are similar, add the next point to set S1;

[0068] Step 3.4, use a straight line segment or an arc segment on the tool plane to fit the points in set S1, calculate the error value between the midpoint of set S1 and the fitted line segment, if the error value does not exceed the preset internal and external thresholds, continue to move forward along the trajectory direction, return to step 3.3 and repeat, continue to add points to set S1, if the error value exceeds the internal and external thresholds, stop fitting, delete the last point in set S1, and use the line segment fitted by the points in set S1 as the new trajectory to replace the short line segment where the midpoint of set S1 is located.

[0069] The curvature of two points is similar by comparing the curvature values ​​calculated at the two points. If the difference in the curvature values ​​is within a preset error range, it means that the curvature of the two points is similar. The preset error range can be set according to actual conditions.

[0070] The trajectory data is fitted and simplified by replacing short line segments with long straight lines and short broken lines with spatial arcs. The purpose is to increase the grinding speed of the equipment, reduce the changes in posture speed in the trajectory, and improve the stability of grinding. The internal and external thresholds need to be pre-set before fitting, and the internal and external thresholds are set differently according to the selected path. When the path to be operated is a flat milling path, the internal and external thresholds are set to 50% to 60% of the tool radius length; when the path to be operated is a side milling path and the path plane is parallel to the tool direction, the internal and external thresholds are set to 50% to 60% of the blade length; when the path to be operated is a side milling path and the path plane is parallel to the tool direction, the internal and external thresholds are set to the residual error value allowed for grinding.

[0071] The control of the relative angle change threshold between the tool normal and the tool feed direction comprises the following steps:

[0072] Step 5.1: When it is detected that consecutive points in the trajectory segment information are on the same plane and the tool height in the Z direction varies, the consecutive points are recorded as point set S2, and the angles between the tool normal and the feed direction for all points in point set S2 are calculated;

[0073] Step 5.2: select any point in the point set S2 as the second starting point;

[0074] Step 5.3: Take other points in point set S2 as comparison points and compare the angle change rate between the second starting point and the comparison point. The angle change rate is the ratio of the difference between the two angles to the distance between the two points.

[0075] Step 5.4: If the angle change rate is greater than the change threshold, use the comparison point as the second starting point and repeat step 5.3 until all points in point set S2 are traversed;

[0076] Step 5.5: If the angle change rate is not greater than the change threshold, delete the comparison point from the point set S2, return to step 5.3 to select the next point as the comparison point, and continue until all points in the point set S2 are traversed.

[0077] Step S3, realizing the overall offset function of the trajectory data in the tool coordinate system, the single-point or multi-point offset function and the re-matching generation of the arc trajectory after offset, as well as the single-point or multi-point posture adjustment.

[0078] Specifically, trajectory data is generated in a theoretical coordinate system. When there is a deviation between the theoretical coordinate system and the actual coordinate system, the entire trajectory data is multiplied (left or right) by the rigid transformation matrix derived from this deviation, thereby performing an overall correction for the deviation. Corrections include overall offset, single-point offset, multi-point offset, and posture adjustment.

[0079] Step S4: Implementing simulation operation of the tool and collision detection.

[0080] Specifically, after optimizing the trajectory data and before implementing tool simulation, the offline programming software can be loaded with the equipment, the corresponding tool, the 3D model of the product, and the G-code program file for processing. The tool simulation and collision detection can then be performed.

[0081] Step S5: Generate an NC program that meets the program standards of a full six-axis CNC rough machining and polishing equipment based on the trajectory data and the tool data, and upload the program to the equipment controller.

[0082] Specifically, the NC program is an automatically generated standardized program, which is automatically or manually uploaded to the equipment controller of the full six-axis CNC rough machining and grinding equipment to facilitate the start of the equipment for rough machining and grinding.

[0083] In step S6, the full six-axis CNC rough machining and polishing equipment sets the workpiece coordinates according to the actual state of the product and starts running the program file.

[0084] Step S7: Offline programming software monitors the equipment operating status in real time.

[0085] Specifically, the offline programming software is the offline programming software for six-axis CNC rough machining and grinding equipment. It monitors the operating status of the equipment during operation. The monitoring parameters include the operating status of the equipment (normal, alarm, etc.), the real-time position of each axis, the status of the equipment IO signal, etc.

[0086] The method disclosed in the present invention is applied to a full six-axis CNC rough machining equipment, as shown in Figures 2 and 3, the full six-axis CNC rough machining equipment includes a machine tool installed on a base, the machine tool is provided with a linear motion axis, a rotary motion axis, a rotary cutter head 8 and a workpiece mounting disk 10, the linear motion axis includes an X-axis 2, a Y-axis 3 and a Z-axis 4, the rotary motion axis includes an A-axis 5, a B-axis 6 and a C-axis 7, the X-axis 2 is located on the machine tool 1, the Y-axis 2 is located on the base 11, the Z-axis 3 is located in front of the X-axis 2, the A-axis 5 is located above the Y-axis 3, the B-axis 6 is located in front of the Z-axis 4, the C-axis 7 is located below the A-axis 5, the workpiece mounting disk 10 is located on the C-axis 7, and the rotary cutter head 10 is located on the B-axis 6. The X-axis 2 is provided with an X-axis screw 12, at the end of which is an X-axis motor 13. The Y-axis 3 is provided with a Y-axis screw 14, at the end of which is a Y-axis motor 15. The Z-axis 4 is provided with a Z-axis screw 16, at the end of which is a Z-axis motor 17. The X-axis is driven by the X-axis motor to reciprocate horizontally, the Y-axis is driven by the Y-axis motor to reciprocate longitudinally, and the Z-axis is driven by the Z-axis motor to reciprocate vertically.

[0087] The A-axis 5 is connected to an A-axis motor 18, with an A-axis RV reducer 19 interposed between the motor and the A-axis 5. The B-axis 6 is equipped with a B-axis motor 20, with a B-axis RV reducer 21 interposed between the motor and the B-axis 6. The C-axis 9 is connected to a C-axis motor 22, with a C-axis RV reducer 23 interposed between the motor and the C-axis 9. In other words, the linear motion axes use servo motors to drive screw drive mechanisms to move on linear guides. The X-axis 2 moves left and right, the Y-axis 3 moves forward and backward, and the Z-axis 4 moves up and down. The rotary motion axes use servo motors to drive high-precision, high-rigidity RV reducers to drive the mechanisms for rotational motion.

[0088] The Y-axis assembly, including the Y-axis, also includes a Y-axis base connected to the Y-axis. The Y-axis assembly is connected to the base via the Y-axis base, and the base has a longitudinal accommodating space for mounting the Y-axis assembly. The Y-axis assembly is provided with a first linear guide and a first slider that slides along the first linear guide. The AC-axis assembly, including the A-axis and the C-axis, is mounted on the first slider of the first linear guide. The AC-axis assembly is provided with an A-axis base having a concave accommodating space. A cradle is suspended from the two side frames of the A-axis base, and the cradle divides the concave accommodating space into upper and lower parts. The A-axis is located at the connection between the cradle and the A-axis base, and the C-axis extends vertically through the center of the cradle. The end of the C-axis is provided with the workpiece mounting plate, which has a workpiece positioning groove.

[0089] The X-axis assembly including the X-axis is installed on the column of the machine tool, the X-axis assembly also includes a second linear guide and a second slider sliding along the second linear guide, the Z-axis assembly including the Z-axis is installed on the second slider, the Z-axis assembly also includes a third linear guide and a third slider sliding along the third linear guide, and the B-axis assembly including the B-axis is installed on the third slider.

[0090] The rotary cutterhead 8 is equipped with roughing tools, including electric spindles and / or floating spindles 27. The electric spindles include electric spindle 1 24, electric spindle 25, and electric spindle 3 26. Electric spindles 25 and 26 are located on the same straight line, with electric spindle 1 24 positioned above electric spindles 25 and 26, and floating spindle 27 positioned below electric spindle 3 26. The rotary cutterhead 8 is a multi-station cutterhead, such as one with four or six tool stations. Rapid tool switching is achieved by rotating and controlling the position of the B-axis 6.

[0091] An adjustable micro-spray device 28 is provided on the Z-axis seat 4 (on the back of the machining tool), which can be used as a cooling and lubricating device to cool down the tool during high-speed operation. The workpiece mounting plate 10 is provided with a positioning position for the fixture, namely the workpiece positioning groove 29, which is convenient for the production of multiple products and ensures the consistency of the fixture after disassembly and assembly; the product on the fixture adopts a multi-cylinder fixing method, and each cylinder is independently controlled. When the operation path interferes with the cylinder fixture, the cylinder switch can be controlled in the program to avoid collision and ensure the continuity of the operation trajectory. There are symmetrically distributed chip guide ports 7 with bevels on both sides of the base 11. The aluminum chips produced by processing pass through the chip guide ports 7 and enter the chip loading trolley for the collection and recycling of aluminum chips.

[0092] The full six-axis spatial interpolation linkage control is a rotating tool center point (RTCP) interpolation linkage function involving all six axes. That is, on the basis of the XYZAB five-axis, the tool head's rotation axis (B-axis) is also taken into account in the RTCP linkage interpolation calculation, so that the tool center point can move according to the specified path and posture in the workpiece coordinate space.

[0093] As shown in Figure 4, the algorithm is used to convert the position and posture of the workpiece coordinate space (X, Y, Z, A, B, C) into a homogeneous transformation matrix M in real time. The matrix is ​​then used to calculate the real-time position (A1, A2, A3, A4, A5, A6) of each electric axis according to the device structure and the relative position of the motion axis, thereby realizing the forward and inverse solution algorithm of the device, thereby controlling the tool center to move according to the set trajectory and posture in the workpiece coordinate space.

[0094] This invention solves the problem of low polishing programming efficiency for complex structural products through an automatic trajectory generation program. One-click threshold simplification solves the problem of excessive trajectory data exported by CAM software, resulting in time-consuming subsequent reading, modification, and positioning. Adjustment and local fine-tuning address the discrepancy between model-generated trajectories and actual equipment operation trajectories. Software algorithms rapidly generate NC programs for polishing operations based on a three-dimensional model of the product being machined. Combined with various operating tools, these processes enable deburring, flash removal, rough milling, and surface polishing of complex structural products.

[0095] This full six-axis CNC rough machining equipment utilizes a real-time method. Machine Tool 1 utilizes a cast body, boasting a lightweight and rigid structure, enabling rapid and precise position changes. Machine Tool 1 implements a fully six-axis Rotating Tool Center Point (RTCP) interpolation linkage function. This incorporates the toolholder's rotational axis (B-axis) into the RTCP linkage interpolation calculations, in addition to the five XYZAB axes. This allows the tool tip to follow a specified path and posture within the workpiece coordinates. The inclusion of the B-axis (6) in the interpolation algorithm increases the redundancy of posture changes, reducing the rotational positions of the A-axis (5) and C-axis (9) during these changes and improving machining efficiency. Furthermore, the addition of the B-axis (6) makes positions and postures difficult to machine with standard five-axis linkage possible.

[0096] The preferred embodiments of the present invention have been described in detail above. It should be understood that numerous modifications and variations based on the concepts of the present invention are possible without inventive effort by those skilled in the art. Therefore, any technical solution that can be derived by one skilled in the art through logical analysis, reasoning, or limited experimentation based on the concepts of the present invention and the prior art should be within the scope of protection defined by the claims.

Claims

1. An offline programming method for a full six-axis CNC rough machining and grinding equipment, characterized in that, It includes the following steps: (1) Import the 3D model of the product into the CAM software, interactively set the workpiece coordinate system and tool coordinate system information, select the path to be processed, and generate trajectory data; (2) Import the 3D model and trajectory data into the offline programming software, and simplify the trajectory data through a fitting algorithm; (3) Implement the overall offset function, single-point or multi-point offset function of the trajectory data in the tool coordinate system, the re-matching generation of the circular arc trajectory after offset, and single-point or multi-point attitude adjustment; (4) Implement the simulation operation of the tool and collision detection; (5) Generate an NC program that meets the program standard of the full six-axis CNC rough machining and grinding equipment according to the trajectory data and tool data, and upload it to the equipment controller; (6) The full six-axis CNC rough machining and grinding equipment sets the workpiece coordinates according to the actual state of the product and starts running the program file; (7) The offline programming software monitors the equipment operation status in real time.

2. The offline programming method of the all-six-axis CNC rough machining and grinding equipment according to claim 1, characterized in that, The simplification process of the trajectory data through the fitting algorithm includes: Conduct field analysis on the trajectory data, extract field data and perform coordinate transformation to obtain the trajectory segment information in the workpiece coordinate system. The field data at least includes instruction mode, point position, coordinate, normal system, and speed; Calculate the curvature value of each point position according to the trajectory segment information, and delete abnormal point positions according to the judgment result of the threshold value of the curvature value of each point position, and retain the curvature value of normal point positions; According to the control of the inner and outer threshold values set in the tool feed direction and the control of the relative angle change threshold value between the tool normal direction and the tool feed direction, perform global adaptive segmentation of linear fitting and spatial circular arc fitting on the normal point positions in the trajectory segment information to achieve the simplification process of the trajectory data.

3. The offline programming method of the all-six-axis CNC rough machining and grinding equipment according to claim 2, characterized in that, The control of the inner and outer threshold values set in the tool feed direction includes the following steps: Step 3.1, create an empty point set S1; Step 3.2, add any point in the trajectory area composed of short line segments as the first starting point to the set S1; Step 3.3, along the trajectory direction of the first starting point, take the next point moving forward as the subsequent point, and judge whether the curvature of the subsequent point is similar to that of the previous point. If the curvatures of the two points are similar, add the subsequent point to the set S1; Step 3.4, fit the points in the set S1 with a straight line segment or an arc segment on the tool plane, calculate the error value between the points in the set S1 and the fitting line segment. If the error value does not exceed the preset inner and outer thresholds, continue to move forward along the trajectory direction and return to step 3.3 to repeat the execution, and continue to add points to the set S1. If the error value exceeds the inner and outer thresholds, stop fitting, delete the last point in the set S1, and use the line segment fitted by the points in the set S1 as the new trajectory to replace the short line segment where the points in the set S1 are located.

4. The offline programming method of the all-six-axis CNC rough machining and grinding equipment according to claim 3, characterized in that, When the path to be machined is a face milling path, the inner and outer thresholds are set to 50% - 60% of the tool radius length; when the path to be machined is a side milling path and the path plane is parallel to the tool direction, the inner and outer thresholds are set to 50% - 60% of the cutting edge length; when the path to be machined is a side milling path and the path plane is perpendicular to the tool direction, the inner and outer thresholds are set to the allowable residual error value for grinding.

5. The offline programming method of the all-six-axis CNC rough machining and grinding equipment according to claim 2, characterized in that, The control of the relative angle change threshold between the tool normal direction and the tool feed direction includes the following steps: Step 5.1, when it is detected that there are consecutive points in the same plane in the trajectory segment information and there is a change in the height of the tool in the Z direction, record the consecutive points as point set S2, and calculate the angle between the tool normal direction and the feed direction of all points in point set S2. Step 5.2, take any point in point set S2 as the second starting point. Step 5.3, take other points in point set S2 as comparison points, and compare the angle change rate between the second starting point and the comparison points. The angle change rate is the ratio of the difference between the two angles to the distance between the two points. Step 5.4, if the angle change rate is greater than the change threshold, take the comparison point as the second starting point, and repeat step 5.3 until all points in point set S2 are traversed. Step 5.5, if the angle change rate is not greater than the change threshold, delete the comparison point from point set S2, return to step 5.3 to select the next point as the comparison point, until all points in point set S2 are traversed.

6. The offline programming method of the all-six-axis CNC rough machining and grinding equipment according to claim 2, characterized in that, When performing linear fitting and spatial circular arc fitting, the least squares method is used to control the error, and the short line segments are changed into long straight lines or spatial circular arc segments.

7. The offline programming method of the all-six-axis CNC rough machining and grinding equipment according to claim 1, characterized in that, The CAM software is specifically MasterCam software, and the trajectory data is the NCI file exported from MasterCam software.

8. The offline programming method of the full six-axis CNC rough machining and grinding equipment according to claim 1, characterized in that, Before realizing the simulation operation of the tool, first load the device, tool, product, and program file in the offline programming software.

9. The offline programming method of the full six-axis CNC rough machining and grinding equipment according to claim 1, characterized in that, The method is applied to a full six-axis CNC roughing equipment. The full six-axis CNC roughing equipment includes a machine tool installed on a base. The machine tool is provided with linear motion axes, rotary motion axes, a rotary tool disc, and a workpiece mounting disc. The linear motion axes include the X-axis, Y-axis, and Z-axis. The rotary motion axes include the A-axis, B-axis, and C-axis. The X-axis is located on the machine tool, the Y-axis is located on the base, the Z-axis is located in front of the X-axis, the A-axis is located above the Y-axis, the B-axis is located in front of the Z-axis, the C-axis is located below the A-axis, the workpiece mounting disc is located on the C-axis, and the rotary tool disc is located on the B-axis.

10. The offline programming method of the all-six-axis CNC rough machining and grinding equipment according to claim 9, characterized in that, The X-axis is provided with an X-axis lead screw, and an X-axis motor is provided at the end of the X-axis lead screw; the Y-axis is provided with a Y-axis lead screw, and a Y-axis motor is provided at the end of the Y-axis lead screw; the Z-axis is provided with a Z-axis lead screw, and a Z-axis motor is provided at the end of the Z-axis lead screw.

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