Adaptive radius compensation overcut processing method and system

Abstract

The invention provides a self-adaptive radius compensation overcut processing method and system, and the method comprises the steps: judging whether a current motion instruction segment belongs to a complex overcut condition or not, carrying out the caching if the current motion instruction segment belongs to the complex overcut, judging whether the total length of the motion instruction segment in the cache meets a preset merging condition or not, and if the total length of the motion instruction segment in the cache meets the preset merging condition, carrying out the caching; and if the total length of the motion instruction segments in the cache meets a preset merging condition, merging the motion instruction segments in the cache. According to the adaptive radius compensation overcut processing method and system provided by the invention, the overcut conditions of the motion instruction sections are judged, and the motion instruction sections with complex overcut conditions are merged, so that the motion instruction sections with complex overcut problems can be re-fitted into a track close to an original processing path, and the processing efficiency is improved. According to the method, the machining continuity is guaranteed, the machining precision and efficiency are improved, meanwhile, additional processing is not conducted on the simple overcutting condition, and the total calculation amount is reduced.

Description

Technical Field

[0001] The present disclosure relates to the technical field of numerical control machining, and in particular to a processing method and system for adaptive radius compensation overcutting. Background Art

[0002] In the traditional CNC machining process, since the size of the machining tool is not fixed, the tool path information generated by the CAM / CAD software usually does not contain the tool radius information. Therefore, in order to solve the impact of the tool radius, radius compensation technology is required to ensure the reliability of machining under different tool radii.

[0003] When using the radius compensation function, due to the irregularity of the tool path, the radius compensation may cause overcutting when processing continuous small line segments. Due to the high complexity of the overcutting problem, in modern machining processes, the overcutting problem is generally solved by modifying the NC program. This type of processing method greatly reduces the machining efficiency and has low adaptability. Summary of the invention

[0004] In view of the above problems, the present disclosure proposes a processing method and system for adaptive radius compensation overcutting.

[0005] In order to solve at least one of the above technical problems, the present disclosure proposes the following technical solutions:

[0006] First, a method for processing overcutting with adaptive radius compensation is provided.

[0007] Determine whether the current motion instruction segment belongs to a complex overcut situation.

[0008] If the current motion instruction segment does not belong to complex overcutting, it will be output directly.

[0009] If the current motion instruction segment is a complex overcut, it will be cached.

[0010] Determine whether the total length of the motion instruction segments in the cache meets the preset merging conditions.

[0011] If the total length of the motion instruction segments in the cache meets the preset merging condition, the motion instruction segments in the cache are merged.

[0012] In some implementations, determining whether the current motion instruction segment belongs to a complex overcut situation includes:

[0013] Get the expressions of the current motion instruction segment and the previous motion instruction segment, and solve the simultaneous equations.

[0014] If the system of equations has a solution, it is a simple overcut.

[0015] If the system of equations has no solution, it is a complex overcut.

[0016] In some embodiments, the preset merging condition is that the total length of the motion instruction segments in the cache is not less than twice the preset length of each motion trajectory after merging, and the preset length of each motion trajectory after merging is not less than the radius compensation amount.

[0017] In some implementations, merging the motion instruction segments in the cache includes:

[0018] Get the original motion trajectory type of the motion instruction segment in the cache, and determine the type of the merged trajectory.

[0019] If the merged trajectory is a straight line, the motion instruction segment is taken out from the cache, and the starting point of the first motion instruction segment taken out is the straight line starting point, and the end point of the last motion instruction segment taken out is the straight line end point, and a straight line motion instruction segment is generated and then output;

[0020] If the merged trajectory is an arc trajectory, take the motion instruction segment from the cache, take the starting point of the first motion instruction segment taken out as the arc starting point, and the end point of the last motion instruction segment taken out as the arc end point. Get the coordinates of the arc midpoint, and generate an arc motion instruction segment with the three points of the arc starting point, arc midpoint and arc end point, and then output it.

[0021] In some implementations, obtaining the coordinates of the arc midpoint includes:

[0022] Assume that the fetched motion instruction segments are L0, L1, ..., L n , n is a natural number, and the length of each motion instruction segment is recorded as l0, l1, ..., l n ,

[0023] Calculate l = (l0 + l1 + ... + l n ) / 2, determine the point corresponding to l and record it as the midpoint of the arc.

[0024] In a second aspect, a processing system for adaptive radius compensation overcutting is provided, which is used to execute any of the above-mentioned processing methods for adaptive radius compensation overcutting, and the system comprises:

[0025] Overcutting judgment module, used to judge whether the current motion instruction segment belongs to complex overcutting situation;

[0026] Cache, used to cache motion instruction segments belonging to complex overcutting situations;

[0027] A merging condition judgment module is used to judge whether the total length of the motion instruction segment in the current cache meets the merging condition;

[0028] The merging processing module is used to merge the motion instruction segments in the cache when the total length of the motion instruction segments in the cache meets the merging condition.

[0029] In some implementations, in the merging condition judgment module, the preset merging condition is that the total length of the motion instruction segments in the cache is not less than twice the radius compensation amount.

[0030] In some implementations, the merging processing module includes an arc midpoint calculation submodule, which is used to calculate the arc midpoint when the merged trajectory is an arc.

[0031] In a third aspect, a numerical control device is provided, which includes at least one processor and a memory connected to the at least one processor, wherein the memory stores at least one instruction, at least one program, code set or instruction set, and the at least one instruction, at least one program, code set or instruction set is loaded by the processor and executed by any of the above-mentioned adaptive radius compensation overcutting processing methods disclosed in the present invention.

[0032] In a fourth aspect, a computer-readable storage medium is provided, in which at least one instruction, at least one program, code set or instruction set is stored, and the at least one instruction, at least one program, code set or instruction set is loaded by a processor and executed by any of the above-mentioned adaptive radius compensation overcutting processing methods disclosed in the present invention.

[0033] The beneficial effect of the present invention is that by judging the overcutting situation of the motion instruction segment and merging the motion instruction segments with complex overcutting problems, the motion instruction segments with complex overcutting problems can be re-fitted into a trajectory close to the original processing path, thereby ensuring the continuity of processing and improving the accuracy and efficiency of processing. At the same time, no additional processing is performed on simple overcutting situations, thereby reducing the overall calculation amount.

[0034] In addition, in the technical solution disclosed in the present invention, unless otherwise specified, the technical solution can be implemented by adopting conventional means in the art. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] In order to more clearly illustrate the specific embodiments of the present disclosure or the technical solutions in the prior art, the drawings required for use in the specific embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present disclosure. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0036] Figure 1 A flowchart of a method for processing adaptive radius compensation overcutting provided by an embodiment of the present disclosure.

[0037] Figure 2 A schematic diagram of the structure of a processing system for adaptive radius compensation overcutting provided by an embodiment of the present disclosure. DETAILED DESCRIPTION

[0038] In order to make the purpose, technical solutions and advantages of the present disclosure more clearly understood, the present disclosure is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are part of the embodiments of the present disclosure, rather than all of the embodiments, and are only used to explain the present disclosure, and are not used to limit the present disclosure. Based on the embodiments in the present disclosure, all other embodiments obtained by ordinary technicians in the field without making creative work are within the scope of protection of the present disclosure.

[0039] It should be noted that the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions. For example, a process, method, system, product or server that includes a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units that are not explicitly listed or are inherent to these processes, methods, products or devices.

[0040] Embodiment 1:

[0041] Reference Manual Attached Figure 1 , shows a method for processing adaptive radius compensation overcutting provided by an embodiment of the present application.

[0042] The processing method of adaptive radius compensation overcutting can specifically include the following steps:

[0043] Step 0: Parse the NC program and obtain the motion instruction segment;

[0044] Step 1: Determine whether the current motion instruction segment belongs to a complex overcut situation. If the current motion instruction segment does not belong to a complex overcut situation, execute step 2. If the current motion instruction segment belongs to a complex overcut situation, execute step 3.

[0045] Step 2: Direct output;

[0046] Step 3: Cache;

[0047] Step 4: Determine whether the total length of the motion instruction segments in the cache meets the preset merging condition. If the total length of the motion instruction segments in the cache meets the preset merging condition, execute step 5. If the total length of the motion instruction segments in the cache does not meet the preset merging condition, repeat steps 1-4.

[0048] Step 5: Merge the motion instruction segments in the cache.

[0049] The NC program can be parsed by the parser to obtain motion instruction segments. Each motion instruction segment corresponds to a motion trajectory, generally including a straight line trajectory and a circular arc trajectory.

[0050] In step 1, determining whether the current motion instruction segment belongs to a complex overcut situation may include:

[0051] Get the expressions of the current motion instruction segment and the previous motion instruction segment, and solve the simultaneous equations.

[0052] If the system of equations has a solution, it is a simple overcut.

[0053] If the system of equations has no solution, it is a complex overcut.

[0054] Specifically, for the plane straight line trajectory, there is an expression as follows:

[0055] Ax+By+C=0;

[0056] For the plane arc trajectory, there is an expression as follows:

[0057] Dx 2 +Ey 2 +Fx+Hy+I=0.

[0058] For a plane straight line trajectory, the straight line expression can be determined according to the straight line starting point and the straight line end point. For a plane arc trajectory, the arc expression can be determined according to the arc starting point, the arc midpoint and the arc end point. Therefore, the expressions of the current motion instruction segment and the previous motion segment are obtained, and the simultaneous equations are solved. If the equations have a solution, it means that the motion trajectory corresponding to the current motion instruction segment and the motion trajectory corresponding to the previous motion instruction segment have an intersection, which is a simple overcut situation. The current motion instruction segment can be directly output. If the equations have no solution, it means that the motion trajectory corresponding to the current motion instruction segment and the motion trajectory corresponding to the previous motion instruction segment do not have an intersection, which is determined to be a complex overcut situation, and the current motion instruction segment is stored in the cache. Therefore, for the motion instruction segment of simple overcut, it does not need to be processed and is directly output, which reduces the overall calculation amount and improves the processing efficiency.

[0059] In an optional embodiment, the preset merging condition may be that the total length of the motion instruction segments in the cache is not less than twice the radius compensation amount. Thus, the motion instruction segments in the cache can be merged into two motion trajectories, and the length of each merged motion trajectory is not less than the radius compensation amount, and the radius compensation algorithm can still be performed after merging. The radius compensation amount is a known parameter.

[0060] In an optional embodiment, the preset merging condition may be that the total length of the motion instruction segments in the cache is not less than twice the length of each motion trajectory after merging, and the length of each motion trajectory after merging is not less than the radius compensation amount. Thus, the motion instruction segments in the cache can be merged into two motion trajectories, and the length of each motion trajectory after merging is not less than the radius compensation amount, and the radius compensation algorithm can still be performed after merging.

[0061] The length of each segment of the motion trajectory after merging can be set according to the actual processing situation. For example, the length of each segment of the motion trajectory after merging can be set to 1.5 times the radius compensation amount, and the preset merging condition can be that the total length of the motion instruction segment in the cache is not less than three times the radius compensation amount. In general, in order to avoid the situation where the length of the motion instruction segment in the cache is not less than 2 times the radius compensation amount, but the length of the second segment of the motion trajectory after merging is less than the radius compensation amount, when setting the length of each segment of the motion trajectory after merging, it can be adjusted according to the length of the motion instruction segment in the NC program, so that the length of each segment of the motion trajectory after merging is greater than the radius compensation amount, for example, it is set to 1.3 times, 1.5 times or 2 times the radius compensation amount, thereby ensuring that the length of each segment of the motion trajectory after merging is greater than the radius compensation amount, so that each segment of the motion trajectory after merging can be subjected to the radius compensation algorithm.

[0062] In an optional embodiment, when the total length of the motion instruction segments in the cache is not less than twice the radius compensation amount, the motion instruction segments in the cache can be fitted into two motion segments.

[0063] In step 5, merging the motion instruction segments in the cache includes:

[0064] Get the original motion trajectory type of the motion instruction segment in the cache, and determine the type of the merged trajectory.

[0065] If the merged trajectory is a straight line, the motion instruction segments are taken out from the cache in the order in which they are stored, and the starting point of the first motion instruction segment taken out is the starting point of the straight line, and the end point of the last motion instruction segment taken out is the end point of the straight line, and a straight line motion instruction segment is generated and then output;

[0066] If the merged trajectory is an arc trajectory, the motion instruction segments are taken out from the cache in the order of storage, the starting point of the first motion instruction segment taken out is the starting point of the arc, the end point of the last motion instruction segment taken out is the end point of the arc, the coordinates of the midpoint of the arc are obtained, and an arc motion instruction segment is generated with the three points of the arc starting point, arc midpoint and arc end point and then output.

[0067] The number of motion instruction segments in the cache is recorded as N. When the total length of the current N-1 motion instruction segments is less than twice the length of each motion trajectory after the merger, and the total length of the N motion instruction segments is less than three times the length of each motion trajectory after the merger, the motion instruction segments in the cache are merged into two motion trajectories in step 5.

[0068] When merging the first trajectory, the number of motion instruction segments taken out is recorded as m. The conditions that the lengths of the m motion instruction segments need to meet are that the total length of the first m-1 motion instruction segments is less than the preset length of each motion trajectory after merging, and the total length of the m motion instruction segments is not less than the preset length of each motion trajectory after merging.

[0069] When merging the second trajectory, the number of motion instruction segments taken out is Nm, and the total length of Nm motion instruction segments is not less than the preset length of each motion trajectory after merging. The preset length of each motion trajectory after merging is not less than the radius compensation amount.

[0070] The number of motion instruction segments in the cache is recorded as N. When the total length of the current N-1 motion instruction segments is less than twice the length of each motion trajectory after merging, and the total length of the N motion instruction segments is not less than three times the length of each motion trajectory after merging, the motion instruction segments in the cache are merged into three motion trajectories in step 5.

[0071] When the number of motion trajectories after merging the motion instruction segments in the cache is 3, it means that the length of the last motion instruction segment is greater than the preset length of each motion trajectory after merging. The Nth instruction segment can be divided into two parts, the first part is used for merging in step 5, and the second part remains unchanged. In this way, the accuracy of the merged trajectory can be effectively guaranteed.

[0072] In an optional embodiment, obtaining the coordinates of the arc midpoint may include:

[0073] Assume that the fetched motion instruction segments are L0, L1, ..., L n , n is a natural number, and the length of each motion instruction segment is recorded as l0, l1, ..., l n ,

[0074] Calculate l = (l0 + l1 + ... + l n ) / 2,

[0075] Use the length l to compare with the sum of the lengths of the first i motion instruction segments taken out, where i is a natural number not greater than n. Find the motion instruction segment corresponding to half of the total length of the motion instruction segment, and determine the point on the motion instruction segment corresponding to half of the total length of the motion instruction segment, and record the point as the midpoint of the arc.

[0076] The starting point of the arc is recorded as S(x1, y1), the end point of the arc is E(x2, y2) and the midpoint of the arc is M(x3, y3). Substitute (x1, y1), (x2, y2) and (x3, y3) as three sets of equations into the circle equation to calculate the circle radius R and the coordinates of the center of the circle (p, q).

[0077] The equation of a circle is given by:

[0078] (xp) 2 +(yq) 2 =R.

[0079] The beneficial effect of the present invention is that by judging the overcutting situation of the motion instruction segment and merging the motion instruction segments with complex overcutting problems, the motion instruction segments with complex overcutting problems can be re-fitted into a trajectory close to the original processing path, thereby ensuring the continuity of processing and improving the accuracy and efficiency of processing. At the same time, no additional processing is performed on simple overcutting situations, thereby reducing the overall calculation amount.

[0080] Embodiment 2:

[0081] Reference Manual Attached Figure 2 The present application also provides an adaptive radius compensation overcutting processing system, which is used to execute any of the aforementioned adaptive radius compensation overcutting processing methods, including:

[0082] An overcutting judgment module 101 is used to judge whether the current motion instruction segment belongs to a complex overcutting situation;

[0083] Cache 102, used to cache motion instruction segments belonging to complex overcutting situations;

[0084] A merging condition judging module 103 is used to judge whether the total length of the motion instruction segments in the current cache meets the merging condition;

[0085] The merging processing module 104 is used to merge the motion instruction segments in the cache when the total length of the motion instruction segments in the cache meets the merging condition.

[0086] In an optional embodiment, in the merging condition judgment module 103, the preset merging condition is that the total length of the motion instruction segments in the cache is not less than twice the radius compensation amount.

[0087] In an optional embodiment, the merging processing module 104 further includes an arc midpoint calculation submodule, which is used to calculate the arc midpoint when the merged trajectory is an arc.

[0088] The beneficial effect of the present invention is that by judging the overcutting situation of the motion instruction segment and merging the motion instruction segments with complex overcutting problems, the motion instruction segments with complex overcutting problems can be re-fitted into a trajectory close to the original processing path, thereby ensuring the continuity of processing and improving the accuracy and efficiency of processing. At the same time, no additional processing is performed on simple overcutting situations, thereby reducing the overall calculation amount.

[0089] The system provided in the above embodiment, when realizing its functions, is only illustrated by the division of the above functional modules. In actual applications, the above functions can be assigned to different functional modules as needed, that is, the internal structure of the device is divided into different functional modules to complete all or part of the functions described above. In addition, the system and method embodiments provided in the above embodiment belong to the same concept, and the specific implementation process is detailed in the method embodiment, which will not be repeated here.

[0090] Embodiment 3:

[0091] The present application provides a numerical control device, which includes:

[0092] One or more processors and memory.

[0093] The numerical control device may also include: an input device and an output device.

[0094] As a non-volatile computer-readable storage medium, the memory can be used to store non-volatile software programs, non-volatile computer executable programs and modules, such as the program instructions / modules corresponding to the processing method for adaptive radius compensation overcutting in the embodiment of the present application. The processor executes various functional applications and data processing of the server by running the non-volatile software programs, instructions and modules stored in the memory, that is, the processing method for adaptive radius compensation overcutting in the above method embodiment is realized.

[0095] The memory may include a program storage area and a data storage area, wherein the program storage area may store an operating system and an application required by at least one function; the data storage area may store data created according to the use of the processing system for adaptive radius compensation overcutting, etc. In addition, the memory may include a high-speed random access memory, and may also include a non-volatile memory, such as at least one disk storage device, a flash memory device, or other non-volatile solid-state storage device. In some embodiments, the memory may optionally include a memory remotely arranged relative to the processor, and these remote memories may be connected to the processing system for adaptive radius compensation overcutting via a network. Examples of the above-mentioned network include, but are not limited to, the Internet, an intranet, a local area network, a mobile communication network, and combinations thereof.

[0096] The input device can receive input digital or character information and generate signal input related to user settings and function control. The output device can include display devices such as display screens.

[0097] One or more modules are stored in the memory, and when executed by one or more processors, the processing method for adaptive radius compensation overcutting in any of the above method embodiments is executed.

[0098] The above device can execute the method provided in the embodiment of the present application, and has the functional modules and beneficial effects corresponding to the execution method. For technical details not described in detail in this embodiment, please refer to the method provided in the embodiment of the present application.

[0099] Embodiment 4:

[0100] On the other hand, embodiment 4 of the present disclosure provides a computer-readable storage medium, which stores one or more programs including execution instructions. The execution instructions can be read and executed by a device (including but not limited to a computer, a server or a network device, etc.) to execute the relevant steps in the above method embodiments.

[0101] The embodiments described above are merely illustrative, wherein the units or modules described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, and may be located in one place or distributed on multiple network units. Some or all of the modules may be selected according to actual needs to achieve the purpose of the solution of this embodiment. Those of ordinary skill in the art may understand and implement it without creative effort.

[0102] Through the description of the above implementation methods, those skilled in the art can clearly understand that each implementation method can be implemented by means of software plus a necessary general hardware platform, or of course by hardware. Based on this understanding, the above technical solution, in essence or in other words, the part that contributes to the prior art, can be expressed in the form of a software product, which can be stored in a computer-readable storage medium, such as ROM / RAM, a disk, an optical disk, etc., including a number of instructions for a computer device (which may be a personal computer, a server or a network device, etc.) to execute the methods of each embodiment or some parts of the embodiment.

[0103] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present disclosure, rather than to limit them. Although the present disclosure has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not make the corresponding technical solutions essentially deviate from the spirit and scope of the technical solutions of the embodiments of the present disclosure.

Claims

1. The processing method of adaptive radius compensation overcutting is characterized by: Determine whether the current motion instruction segment belongs to a complex overcut situation. If the current motion instruction segment does not belong to complex overcutting, it will be output directly. If the current motion instruction segment is a complex overcut, it will be cached. Determine whether the total length of the motion instruction segments in the cache meets the preset merging conditions. If the total length of the motion instruction segments in the cache meets the preset merging condition, the motion instruction segments in the cache are merged.

2. The method for processing adaptive radius compensation overcut according to claim 1, characterized in that: Judging whether the current motion instruction segment belongs to complex overcutting includes: Get the expressions of the current motion instruction segment and the previous motion instruction segment, and solve the simultaneous equations. If the system of equations has a solution, it is a simple overcut. If the system of equations has no solution, it is a complex overcut.

3. The method for processing adaptive radius compensation overcut according to claim 1, characterized in that: The preset merging condition is that the total length of the motion instruction segments in the cache is not less than twice the preset length of each motion trajectory after merging, and the preset length of each motion trajectory after merging is not less than the radius compensation amount.

4. The method for processing adaptive radius compensation overcut according to claim 1, characterized in that: The merging process of the motion instruction segments in the cache includes: Get the original motion trajectory type of the motion instruction segment in the cache, and determine the type of the merged trajectory. If the merged trajectory is a straight line, the motion instruction segment is taken out from the cache, and the starting point of the first motion instruction segment taken out is the straight line starting point, and the end point of the last motion instruction segment taken out is the straight line end point, and a straight line motion instruction segment is generated and then output; If the merged trajectory is an arc trajectory, take the motion instruction segment from the cache, take the starting point of the first motion instruction segment taken out as the arc starting point, and the end point of the last motion instruction segment taken out as the arc end point. Get the coordinates of the arc midpoint, and generate an arc motion instruction segment with the three points of the arc starting point, arc midpoint and arc end point, and then output it.

5. The method for processing adaptive radius compensation overcut according to claim 4, characterized in that: Getting the coordinates of the arc midpoint includes: Assume that the fetched motion instruction segments are L0, L1, ..., L n , n is a natural number, and the length of each motion instruction segment is recorded as l0, l1, ..., l n , Calculate l = (l0 + l1 + ... + l n ) / 2, determine the point corresponding to l and record it as the midpoint of the arc.

6. An adaptive radius compensation overcutting processing system, used to execute the adaptive radius compensation overcutting processing method according to any one of claims 1 to 5, characterized in that: include, Overcutting judgment module, used to judge whether the current motion instruction segment belongs to complex overcutting situation; Cache, used to cache motion instruction segments belonging to complex overcutting situations; A merging condition judgment module is used to judge whether the total length of the motion instruction segment in the current cache meets the merging condition; The merging processing module is used to merge the motion instruction segments in the cache when the total length of the motion instruction segments in the cache meets the merging condition.

7. The processing system for adaptive radius compensation overcutting according to claim 6, characterized in that: In the merging condition judgment module, the preset merging condition is that the total length of the motion instruction segments in the cache is not less than twice the radius compensation amount.

8. The processing system for adaptive radius compensation overcutting according to claim 6, characterized in that: The merging processing module includes an arc midpoint calculation submodule, which is used to calculate the arc midpoint when the merged trajectory is an arc.

9. A numerical control device, characterized in that: The numerical control device includes a processor and a memory, wherein the memory stores at least one instruction, at least one program, a code set or an instruction set, and the at least one instruction, the at least one program, the code set or the instruction set is loaded and executed by the processor to implement the processing method for adaptive radius compensation overcutting as described in any one of claims 1-5.

10. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores at least one instruction, at least one program, a code set or an instruction set, and the at least one instruction, the at least one program, the code set or the instruction set are loaded and executed by the processor to implement the processing method for adaptive radius compensation overcutting described in any one of claims 1-5.

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