Simulation device and computer-readable recording medium

Abstract

Provided is a simulation device for simulating machining of a machine tool, the simulation device being configured to calculate a designable range of a voxel size on the basis of workpiece shape data, present the designable range of the voxel size to a user, receive designation of the voxel size, and create an image, in which machining of the machine tool is simulated, on the basis of the designated voxel size.

Description

Technical Field

[0001] The present invention relates to a simulation device and a computer-readable recording medium.

Background Art

[0002] Conventionally, there is a technique for creating a simulation image using a movement command from a numerical control device to a machine tool and feedback data from a servo motor to the numerical control device. In the simulation image, the state of the actual machining surface is displayed. In high-definition simulations, unevenness on the order of several micrometers is represented.

[0003] In 3D computer graphics, for example, a workpiece or a tool is represented as a set of 3D cubes called voxels. The size of a voxel is related to the display accuracy, and the number of voxels is related to the display time. With reference to FIG. 9, the relationship between the display accuracy and the display time will be described. FIG. 9 represents a 3D image in 2D for explanatory purposes.

[0004] In FIG. 9, the size of the voxels in the left figure is smaller than the size of the voxels in the right figure. The tool trajectory in the figure is the range cut by the tool, and the portion adjacent to the tool trajectory in the figure is an error in display. When the size of the voxels is small, the area of the error is small and the accuracy is high, but since the number of voxels is large, the calculation time and the drawing time become long. When the size of the voxels is large, the area of the error is large and the accuracy is low, but since the number of voxels is small, the calculation time and the drawing time become short.

[0005] Conventionally, in order to increase the display accuracy while shortening the display time, there is a technique of "detecting the voxels in contact with the tool and dividing these voxels, thereby minimizing the number of voxels to be divided and reducing the amount of arithmetic processing". See, for example, Patent Document 1.

Prior Art Documents

Patent Documents

[0006] [Patent Document 1] Japanese Patent Application Laid-Open No. 2008-287456 [Summary of the Invention] [Problems to be Solved by the Invention]

[0007] In the field of simulation of machine tools, a technique for improving display accuracy while shortening the time required for display is desired. [Means for Solving the Problems]

[0008] A simulation device according to an aspect of the present disclosure is a simulation device that simulates machining of a machine tool, At least one of the tool shape data and the machining accuracy, and a voxel size calculation unit that calculates a specifiable range of voxel size based on workpiece shape data, a voxel size specification reception unit that presents the specifiable range of voxel size to a user and receives a specification of the voxel size, and a simulation image creation unit that creates a simulation image of machining of the machine tool based on the voxel size received by the voxel size specification reception unit. A recording medium according to an aspect of the present disclosure, when executed by one or more processors, At least one of the tool shape data and the machining accuracy, and calculates a specifiable range of voxel size based on workpiece shape data, presents the specifiable range of voxel size to a user, receives a specification of the voxel size, and records instructions for creating a simulation image of machining of a machine tool based on the received voxel size specification. [Advantages of the Invention]

[0009] According to an aspect of the present invention, it is possible to improve display accuracy while shortening the time required for display in simulation. [Brief Description of the Drawings]

[0010]

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Figure 5B

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Embodiments for Carrying Out the Invention

[0011] Hereinafter, the simulation device 100 of the present disclosure will be described. The simulation device 100 of the present disclosure is implemented in an information processing device that acquires movement commands of a tool of a machine tool and servo feedback data and displays the machining status of the machine tool as a three-dimensional image. Examples of the information processing device include, but are not limited to, a numerical control device, a PC (personal computer), etc.

[0012] FIG. 1 is a block diagram of the simulation device 100. The simulation device 100 includes a workpiece shape data storage unit 11, a tool shape data storage unit 12, a tool path data storage unit 13, a machining program storage unit 14, a simulation image generation unit 15, a voxel size calculation unit 16, an accuracy condition setting unit 17, and a voxel size designation reception unit 18.

[0013] The workpiece shape data storage unit 11 stores the shape of the workpiece machined by the machine tool. The workpiece shape data stores the size of the workpiece or a value for calculating the size of the workpiece. The tool shape data storage unit 12 stores the shape of the tool. Based on the tool shape data, the size and type of the tool can be known.

[0014] The machining program storage unit 14 stores the machining program of the machine tool. The machining accuracy can be known from the G code described in the machining program and the comments of the program. For example, rough machining has low machining accuracy, and precision machining has high machining accuracy. The machining accuracy affects the voxel size.

[0015] The tool path data storage unit 13 stores the movement command output by the numerical control device to the machine tool or the tool path calculated based on the feedback data from the servo.

[0016] The simulation image generation unit 15 draws three-dimensional images of the workpiece and the tool based on the workpiece shape data and the tool shape data. The simulation image generation unit 15 acquires the movement amount of the tool for each time from the tool path data storage unit 13. At this time, the posture of the tool with respect to the workpiece may be acquired. The simulation image generation unit 15 calculates the interference between the tool and the workpiece based on the tool path and the tool posture. When the tool interferes with the workpiece represented by voxels, the voxels that are partially or entirely present inside the tool are removed, and the shape change of the workpiece in machining is simulated.

[0017] The accuracy condition setting unit 17 receives from the user the setting of the accuracy condition that is the calculation condition of the voxel size. FIG. 2 is an example of the accuracy condition setting screen. On the accuracy condition setting screen, at least one of the workpiece shape, the tool shape, and the machining type can be selected. When the workpiece shape is selected, the range of the voxel size is calculated based on the size of the workpiece. When the tool shape is calculated, the range of the voxel size is calculated based on the tool shape and the type of the tool. When the machining accuracy is selected, the range of the voxel size is calculated based on the machining accuracy. On the accuracy condition setting screen, two conditions such as the workpiece shape and the tool shape, the tool shape and the machining accuracy, and the machining accuracy and the workpiece shape can be set. Also, three conditions of the workpiece shape, the tool shape, and the machining accuracy can be set.

[0018] In the accuracy condition setting unit 17, it may be set whether accuracy priority or speed priority as the user's priority condition. Fig. 3 is another example of the accuracy condition setting screen. On the accuracy condition setting screen of Fig. 3, either one of accuracy priority or speed priority can be set.

[0019] The voxel size calculation unit 16 calculates the specifiable range of the voxel size based on the accuracy conditions. The specifiable range of the voxel size is the range of the voxel size that the user can specify. When the workpiece shape is set as the accuracy condition, the voxel size calculation unit 16 reads, for example, the size of the workpiece from the workpiece shape data storage unit 11. The size of the workpiece may be calculated based on the workpiece shape. The voxel size calculation unit 16 calculates the range of the voxel size that the user can specify based on the size of the workpiece, the amount of memory used for the simulation, and the calculation load. Specifically, the voxel size is related to the size of the workpiece. The larger the workpiece, the larger the voxel size can be. The number of voxels is limited by hardware resources such as the amount of memory used for the simulation. The voxel size calculation unit 16 calculates the range of the voxel size that does not exceed the limit of the number of voxels and conforms to the accuracy conditions and the priority conditions.

[0020] When the tool shape is set as the accuracy condition, the voxel size that conforms to the size and type of the tool is calculated. When the tool is large, the machining accuracy is not high, so the voxel size may be large. Also, when the tool is small or when a tool with high machining accuracy is used, the machining accuracy is high, so the voxel size should be small. Specifically, if the type of the tool is for rough machining, large voxels may be used, and if the type of the tool is for finish machining, small voxels are more suitable. As a precision condition, when the machining precision is set, the machining precision is judged, and the voxel size corresponding to the machining precision is calculated. The judgment of the machining precision is made, for example, from the machining program. The machining precision can be judged from the G-code or program comments of the machining program. When machining conditions for low machining precision such as rough machining are set, or when the machining purpose is described as rough machining in the program comments, the voxels may be large. When machining conditions for high machining precision such as finish machining or precision machining are set, or when the machining purpose is described as finish machining or precision machining in the program comments, smaller voxels are more suitable. The voxel size also changes according to the user's priority conditions. When the user sets precision priority, the voxel size becomes smaller, and when the user sets speed priority, the voxel size becomes larger.

[0021] Figure 4 is an example of the calculation result of the voxel size. It is an example when the work shape is set as the precision condition and precision priority is set as the priority condition. When the size of the work is 100 mm, if precision priority is set, the voxel size will be 0.01 mm, and if speed priority is set, it will be 1 mm. When the size of the work is 1000 mm, if precision priority is set, the voxel size will be 0.1 mm, and if speed priority is set, it will be 10 mm. The larger the size of the work, the larger the voxel size. If precision priority is set, the voxel size will be smaller, and if speed priority is set, the voxel size will be larger. As precision conditions, when the tool shape and machining precision are set, a voxel size suitable for the set conditions is calculated.

[0022] The voxel size specifying reception unit 18 displays the range of the voxel size and receives the specification of the voxel size. FIGS. 5A and 5B are examples of the voxel size specifying screen. It is a voxel size reception screen when the workpiece shape is selected as the accuracy condition. FIG. 5A is a voxel size specifying screen when the workpiece size is 100 mm, and it receives the voxel size in the range from accuracy priority (0.01 mm) to speed priority (1 mm). FIG. 5B is a voxel size specifying screen when the workpiece size is 1000 mm, and it receives the voxel size in the range from accuracy priority (0.1 mm) to speed priority (10 mm).

[0023] The simulation image generation unit 15 creates a simulation image based on the voxel size calculated by the voxel size calculation unit 16 or the voxel size received by the voxel size specifying reception unit 18. The left figure in FIG. 6 shows a simulation image with high display accuracy, and the right figure shows a simulation image with low display accuracy. The advantage of a small voxel size is high display accuracy. The disadvantage is that the calculation time for cutting off voxels is long, and the drawing time of voxels is long because the number of voxels is large. The advantage of a large voxel size is that the calculation time for cutting off voxels is short and the drawing time of voxels is short. The disadvantage is low display accuracy.

[0024] Referring to FIG. 7, the operation of the simulation device 100 of the present disclosure will be described. The simulation device 100 receives the accuracy condition (step S1). As the accuracy condition, for example, at least one of the workpiece shape, tool shape, and processing type is received. Note that the accuracy condition may be set not by the user but by the simulation device 100.

[0025] The simulation device 100 receives the priority condition (step S2). As the priority condition, for example, there are accuracy priority and speed priority.

[0026] The simulation device 100 calculates the range of voxel sizes based on accuracy conditions and priority conditions (step S3). The simulation device 100 presents the range of voxel sizes to the user and accepts the specification of the voxel size (step S4).

[0027] When the voxel size is specified, the simulation device 100 acquires information indicating the tool path, such as a movement command for the tool of the machine tool from the numerical control device or servo feedback data (step S5). The movement command for the tool or servo feedback may be read from the tool path data storage unit 13 instead of being acquired in real time. The simulation device 100 calculates the interference between the tool and the workpiece based on the movement command for the tool or servo feedback data. When the tool interferes with the workpiece represented by voxels, the simulation device 100 removes the voxels existing inside the tool, simulates the shape change of the workpiece in machining, and creates a simulation image (step S6). Since the voxel size is set to an appropriate size according to the workpiece shape, tool shape, type of machining, and the user's priority conditions, a simulation image can be created with the accuracy or speed desired by the user.

[0028] As described above, the simulation device 100 of the present disclosure automatically calculates the range within which the voxel size can be specified by the user based on the workpiece shape, tool shape, machining accuracy, etc. The user can specify an appropriate voxel size within this calculated specifiable range by setting priority conditions and the like. Thereby, a simulation image can be created with the accuracy and speed suitable for the user's purpose.

[0029] The accuracy condition may be any one of the workpiece shape, tool shape, and machining accuracy, or a combination thereof. The voxel size can also be adjusted according to whether the user values accuracy or speed.

[0030] Note that the present disclosure may be combined with other display accuracy improvement means and drawing device improvement means. For example, in the present disclosure, the voxel size on the workpiece surface may be made finer to improve the display accuracy and drawing speed.

[0031] [Hardware Configuration] With reference to FIG. 8, the hardware configuration of the simulation device 100 will be described. The CPU 111 included in the simulation device 100 is a processor that controls the entire simulation device 100. The CPU 111 reads out the system program processed in the ROM 112 via the bus and controls the entire simulation device 100 according to the system program. Temporary calculation data, display data, various data input by the user via the input unit 71, etc. are temporarily stored in the RAM 113.

[0032] The display unit 70 is a monitor or the like attached to the simulation device 100. The display unit 70 displays the operation screen, setting screen, etc. of the simulation device 100.

[0033] The input unit 71 is integrated with the display unit 70 or is a separate keyboard, touch panel, etc. from the display unit 70. The user operates the input unit 71 to input to the screen displayed on the display unit 70. Note that the display unit 70 and the input unit 71 may be a mobile terminal.

[0034] The non-volatile memory 114 is a memory that retains its stored state even when the power of the simulation device 100 is turned off, for example, by being backed up with a battery (not shown). The non-volatile memory 114 stores workpiece shape data, tool shape data, tool path data, and machining programs. In the non-volatile memory 114, programs read from external devices via an interface (not shown), programs input via the input unit 71, and various types of data (e.g., setting parameters obtained from the machine tool, etc.) acquired from each part of the simulation device 100 and the machine tool are stored. The programs and various types of data stored in the non-volatile memory 114 may be expanded to the RAM 113 during execution / use. Also, various system programs are pre-written in the ROM 112.

Explanation of Signs

[0035] 100 Simulation device 11 Workpiece shape data storage section 12 Tool shape data storage section 13 Tool path data storage section 14 Machining program storage section 15 Simulation image generation section 16 Voxel size calculation section 17 Precision condition setting section 18 Voxel size specification reception section 70 Display section 71 Input section 111 CPU 112 ROM 113 RAM 114 Non-volatile memory

Claims

1. A simulation device for simulating the machining of a machine tool, comprising: a voxel size calculation unit that calculates a specifiable range of voxel size based on at least one of tool shape data and machining accuracy, and workpiece shape data; a voxel size specification reception unit that presents the specifiable range of the voxel size to the user and receives the specification of the voxel size; a simulation image creation unit that creates a simulation image of the machining of the machine tool based on the voxel size received by the voxel size specification reception unit; A simulation device comprising the above.

2. The simulation device according to claim 1, wherein the tool shape data includes at least one of the size of the tool and the type of the tool.

3. Further comprising an accuracy condition setting unit that receives the user's priority conditions, wherein the priority conditions are at least one of an accuracy priority condition and a speed priority condition for creating the simulation image, and the specifiable range of the voxel size is presented in association with the priority conditions. The simulation device according to claim 1.

4. By one or more processors executing, calculating a specifiable range of voxel size based on at least one of tool shape data and machining accuracy, and workpiece shape data, presenting the specifiable range of the voxel size to the user and receiving the specification of the voxel size, creating a simulation image of the machining of the machine tool based on the received voxel size specification, A storage medium storing instructions readable by the processor.

Images