A control device and a computer-readable recording medium recording a program

Abstract

A control device according to the present disclosure comprises: a low-pass filter unit that generates a smoothed path by subjecting an indicated path, which is indicated by a control program, to smoothing by a low-pass filter; an inward turning amount calculation unit that calculates an inward turning amount that is the amount of inward turning of the smoothed path generated by the low-pass filter unit relative to the indicated path; and a smoothing processing unit that outputs a path obtained by turning back the smoothed path in a direction opposite to the inward turning direction on the basis of the inward turning amount.

Description

Technical Field

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

Background Art

[0002] When creating a control program for machining a smooth free-form surface with industrial machines such as machine tools and electrical discharge machines, curves created in CAD (Computer Aided Design) are converted into a point sequence by CAM (Computer Aided Manufacturing). These points are referred to as command points. By converting the curve into a command point sequence, it is expressed as a plurality of continuous minute line segments.

[0003] FIG. 7 is a diagram illustrating a sequence of a plurality of command points converted by CAM. In FIG. 7, a plurality of command points 422 are indicated by black circles, and minute line segments 424 between the command points 422 are indicated by dotted arrows. As shown in FIG. 7, the movement path composed of the minute line segments 424 has a polyhedral shape. The control device creates a smooth tool path based on a plurality of minute points or a plurality of minute line segments commanded by this control program (for example, Patent Document 1, etc.). Then, by machining while relatively moving the tool along the smooth tool path with respect to the workpiece, a smooth machined surface is formed.

[0004] One method of creating a smooth tool path from a plurality of minute line segments is a method of performing smoothing using a low-pass filter such as a moving average filter. FIG. 8 shows an example of a curve path (hereinafter referred to as a smoothing path) created by smoothing a polygonal path composed of a plurality of continuous minute line segments with a low-pass filter. In FIG. 8, the smoothing path 426 is indicated by a solid arrow. Smoothing by a low-pass filter has the merit of reducing the step difference between adjacent paths.

Prior Art Documents

Patent Documents

[0005] [Patent Document 1] Japanese Patent Application Laid-Open No. 2000-353006 [Summary of the Invention] [Problems to be Solved by the Invention]

[0006] As illustrated in FIG. 8, the smoothing path 426 by the low-pass filter becomes a path shifted in the direction of the principal normal vector of the curve (the inner direction of the curve of the curve) passing through the plurality of command points 422 as compared with the original polygonal path. In this specification, the amount of such a shift is referred to as the amount of inward rotation. Therefore, although the smoothing path is smooth, it passes through a position shifted from the command point 422. That is, the machining accuracy (shape accuracy) is reduced. When performing the smoothing process, it is possible to suppress the reduction of the machining accuracy to some extent by setting the tolerance (allowable error). However, if a strict tolerance is set in an attempt to suppress the reduction of the machining accuracy, a problem occurs that the path does not become sufficiently smooth. Therefore, a technique for sufficiently smoothing the machining path while maintaining the machining accuracy is desired. [Means for Solving the Problems]

[0007] The control device according to the present disclosure performs correction so that the smoothed curve approaches a plurality of command points in consideration of the amount of inward rotation, which is the deviation of the path that occurs when smoothing processing is performed by a low-pass filter. This correction may be performed on the smoothing path after the smoothing process, or may be performed on the command points to be processed before the smoothing process. The smoothing path or the command point is corrected in the reverse direction of the principal normal vector of the curve passing through the plurality of command points (the outer direction of the curve of the curve).

[0008] And one aspect of the present disclosure is a control device that controls the machining of a workpiece by an industrial machine based on a control program, the low-pass filter unit that generates a smoothing path by performing smoothing by a low-pass filter on the command path commanded by the control program, Based on the curvature of the command path and the filter length of the low-pass filter,An in-rotation amount calculation unit that calculates an in-rotation amount in a direction of rotating inward with respect to the command path of the smoothing path obtained by the low-pass filter unit, and a smoothing processing unit that outputs a path in which the smoothing path is pulled back in a direction opposite to the in-rotation direction based on the in-rotation amount. The control device includes these units.

[0009] Another aspect of the present disclosure is a computer-readable recording medium recording a program for operating a control device that controls the processing of a workpiece by an industrial machine based on a control program. The computer-readable recording medium includes a low-pass filter unit that generates a smoothing path by performing smoothing on a command path commanded by the control program using a low-pass filter, Based on the curvature of the command path and the filter length of the low-pass filter, An in-rotation amount calculation unit that calculates an in-rotation amount in a direction of rotating inward with respect to the command path of the smoothing path obtained by the low-pass filter unit, and a smoothing processing unit that outputs a path in which the smoothing path is pulled back in a direction opposite to the in-rotation direction based on the in-rotation amount. The computer-readable recording medium is a recording medium recording a program for operating a control device as these units.

Advantages of the Invention

[0010] According to one aspect of the present disclosure, a smooth and highly accurate path (without a decrease in accuracy due to inward rotation) can be obtained. Therefore, a processed workpiece with a smooth processed surface and no deterioration in shape accuracy can be obtained.

Brief Description of the Drawings

[0011]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Embodiments for Carrying Out the Invention

[0012] Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a schematic hardware configuration diagram showing a main part of a control device according to a first embodiment of the present invention. The control device 1 of the present invention can be implemented as a control device that controls industrial machines such as machine tools, electric discharge machines, and robots based on, for example, a control program. Hereinafter, the control device 1 according to the present embodiment will be described by taking, as an example, a control device that controls a machine tool that processes a workpiece by moving a tool relative to the workpiece based on a control program.

[0013] The CPU 11 included in the control device 1 according to the present embodiment is a processor that controls the control device 1 as a whole. The CPU 11 reads out a system program stored in the ROM 12 via the bus 22 and controls the entire control device 1 according to the system program. Temporary calculation data, display data, and various data input from the outside are temporarily stored in the RAM 13.

[0014] The non-volatile memory 14 is composed of, for example, a memory backed up by a battery (not shown) or an SSD (Solid State Drive), etc., and retains its stored state even when the power supply of the control device 1 is turned off. The non-volatile memory 14 stores data acquired from the industrial machine 2, control programs and data read from an external device 72 via the interface 15, control programs and data input via the input device 71, control programs and data acquired from other devices via the network 5, etc. The control programs and data stored in the non-volatile memory 14 may be expanded to the RAM 13 during execution / use. Also, various system programs such as known analysis programs are pre-written in the ROM 12.

[0015] The interface 15 is an interface for connecting the CPU 11 of the control device 1 and an external device 72 such as a USB device. From the external device 72 side, for example, control programs and setting data used for controlling the industrial machine 2 are read. Also, control programs and setting data edited within the control device 1 can be stored in external storage means via the external device 72. The PLC (Programmable Logic Controller) 16 executes a ladder program and outputs and controls signals to the industrial machine 2 and peripheral devices of the industrial machine 2 (for example, a tool changer, actuators of a transfer robot, a plurality of sensors such as a temperature sensor and a humidity sensor attached to the industrial machine 2) via the I / O unit 19. Also, it receives signals from various switches on the operation panel and peripheral devices provided on the main body of the industrial machine 2, performs necessary signal processing, and then passes the signals to the CPU 11. c) and outputs and controls signals via the I / O unit 19. Also, it receives signals from various switches on the operation panel and peripheral devices provided on the main body of the industrial machine 2, performs necessary signal processing, and then passes the signals to the CPU 11.

[0016] The interface 20 is an interface for connecting the CPU of the control device 1 and a wired or wireless network 5. Connected to the network 5 are other industrial machines 4 such as machine tools and electrical discharge machines, fog computers 6, cloud servers 7, etc., and data is exchanged mutually with the control device 1.

[0017] In the display device 70, each data read onto the memory, data obtained as a result of execution of a program, etc. are output and displayed via the interface 17. Further, the input device 71 composed of a keyboard, a pointing device, etc. passes commands, data, etc. based on operations by the operator to the CPU 11 via the interface 18.

[0018] The axis control circuit 30 for controlling the axes provided in the industrial machine 2 receives the axis movement command amount from the CPU 11 and outputs the axis command to the servo amplifier 40. The servo amplifier 40 receives this command and drives the servo motor 50 that moves the axis provided in the machine tool. The axis servo motor 50 incorporates a position / velocity detector, and feeds back the position / velocity feedback signal from this position / velocity detector to the axis control circuit 30 to perform position / velocity feedback control. Note that in the hardware configuration diagram of FIG. 1, only one each of the axis control circuit 30, the servo amplifier 40, and the servo motor 50 is shown, but actually, they are prepared in the number of axes provided in the industrial machine 2 to be controlled.

[0019] FIG. 2 shows, as a schematic block diagram, the functions provided in the control device 1 according to the first embodiment of the present invention. Each function provided in the control device 1 according to the present embodiment is realized by the CPU 11 provided in the control device 1 shown in FIG. 1 executing a system program and controlling the operations of each part of the control device 1.

[0020] The control device 1 of the present embodiment includes an analysis unit 100, a smoothing processing unit 110, a low-pass filter unit 112, an inner rotation amount calculation unit 114, and a motor control unit 120. Further, a control program 200 for controlling the operation of the industrial machine 2 is stored in advance in the RAM 13 to the non-volatile memory 14 of the control device 1.

[0021] The analysis unit 100 reads and analyzes the blocks of the control program 200, and generates movement command data for the servo motors 50 that drive each part of the industrial machine 2. Based on the feed command commanded by the blocks of the control program 200, the analysis unit 100 generates data related to the movement command for the servo motor 50 that relatively moves the tool of the industrial machine 2 with respect to the workpiece. The data related to the generated movement command includes at least a sequence of a plurality of command points. The analysis unit 100 outputs the data related to the generated movement command to the smoothing processing unit 110.

[0022] The smoothing processing unit 110 generates a smoothed path by smoothing the movement path composed of a sequence of a plurality of command points included in the data related to the movement command input from the analysis unit 100. The smoothed path generated by the smoothing processing unit 110 takes into account the amount of inward rotation calculated by the inward rotation amount calculation unit 114, and is also based on the curved path generated by the low-pass filter unit 112.

[0023] The low-pass filter section 112 generates a smoothed path by applying smoothing with a low-pass filter to a path composed of a plurality of minute line segments obtained by connecting between a plurality of command points. When applying a low-pass filter to a path composed of a plurality of minute line segments, the low-pass filter section 112 defines the path composed of the plurality of minute line segments as, for example, a parametric curve P(t). Here, P(t) is a vector having coordinate values of each axis as elements, and the dimension of the vector matches the number of axes. For example, when the industrial machine 2 relatively moves a tool and a workpiece by an X-axis, a Y-axis, and a Z-axis, P(t) becomes a three-dimensional vector. t is a parameter of the parametric curve. Since the method of representing the path commanded by the control program 200 by a parametric curve is a known technique, it will be omitted. When defined in this way, if the curve path obtained by applying a smoothing process to the path P(t) is Q(t), Q(t) can be calculated by the following Equation (1). In Equation (1), F(l) represents a filter operation by a low-pass filter. As the low-pass filter, for example, a known moving average filter, a Gaussian convolution filter, or the like can be used. At this time, l is a parameter representing the application range (filter length) of the filter. The filter length may be calculated based on at least any one of the moving time, the moving distance, the moving speed of the tool along the commanded path, and the time constant determined by the filter. By setting the filter length to be about the length of the minute line segment constituting the path (when the parameter t of the parametric curve is a unit of time, about the time related to the movement of the minute line segment), a polygonal path can be made sufficiently smooth. When the control program 200 is represented by minute line segments, the filter length is generally applied in a range longer than the line segment length. This line segment length may be checked in advance before the filter process or may be given separately.

[0024]

Equation

[0025] As the low-pass filter used by the low-pass filter section 112 for smoothing, other known low-pass filters may be used.

[0026] The inner rotation amount calculation unit 114 calculates the amount of inner rotation of a smoothing path generated by applying a low-pass filter to a path composed of a plurality of minute line segments obtained by connecting between a plurality of command points.

[0027] The inner rotation amount calculation unit 114 may calculate the inner rotation amount, for example, by simply taking the difference between a path composed of a plurality of minute line segments and the smoothing path. For example, the inner rotation amount may be calculated at a predetermined parameter period using the following Equation 2. In Equation 2, d(t) is the inner rotation amount (scalar value) at the position of a predetermined parameter.

[0028]

Equation

[0029] FIG. 3 is a diagram illustrating the inner rotation amount of a smoothing path with respect to a path composed of a plurality of minute line segments. In FIG. 3, the command point 422 is shown as a black circle, the minute line segment 424 is shown as a dotted arrow, and the smoothing path 426 is shown as a solid arrow. Note that FIG. 3 is drawn such that the smoothing path rotates more inward than in reality in order to make it easier to grasp the inner rotation amount. As illustrated in FIG. 3, when calculating the inner rotation amount by simply taking the difference between the path composed of minute line segments and the smoothing path, for example, the inner rotation amount at the position of the command point 422 or the inner rotation amount at the position of the value of a predetermined parameter t between the command points 422 can be calculated.

[0030] The inner rotation amount calculation unit 114 may, for example, calculate only the inner rotation amount at the position of the command point 422 using Equation 2 and calculate the inner rotation amount at other positions by proportional distribution or the like. For example, assume that the value of the parameter t at the position of a predetermined command point is ts and the value of the parameter t at the position of the next command point is te. At this time, the value a shown in the following Equation 3 is uniquely determined.

[0031]

Number

[0032] Using this value a, the amount of inward rotation at a predetermined position between command points may be calculated by the following Equation 4.

[0033]

Number

[0034] The inward rotation amount calculation unit 114 may approximately calculate the inward rotation amount based on, for example, the curvature of the smoothing curve. The radius of curvature R(t) at a predetermined position of the smoothing curve Q(t) can be obtained by a known analytical method or an approximate method from the parametric curve. When the arc path of this radius of curvature R(t) is Circle(R), the inward rotation amount d(t) satisfies the following Equation 5. By analytically or approximately solving this Equation 5 for d(t), the inward rotation amount can be calculated.

[0035]

Number

[0036] The smoothing processing unit 110 may generate a smoothing path passing near the command point by correcting the smoothing path generated by the low-pass filter unit 112 based on the inward rotation amount calculated by the inward rotation amount calculation unit 114 in this way. As another method, correction points obtained by moving the command points in advance are calculated based on the inward rotation amount calculated by the inward rotation amount calculation unit 114. Then, a smoothing path passing near the command point may be generated by applying a filter to the corrected movement path composed of a sequence of a plurality of these correction points by the low-pass filter unit 112.

[0037] The motor control unit 120 controls the servo motor 50 provided in the industrial machine 2 so that the tool and the workpiece move relative to each other along the smoothed path generated by the smoothing processing unit 110.

[0038] According to one aspect of the present disclosure having the above configuration, a smooth and highly accurate (without a decrease in accuracy due to inward rotation) path can be obtained. Therefore, a processed workpiece with a smooth processed surface and no deterioration in shape accuracy can be obtained.

[0039] FIG. 4 shows, as a schematic block diagram, the functions provided in the control device 1 according to the second embodiment of the present invention. Each function provided in the control device 1 according to the present embodiment is realized by the CPU 11 provided in the control device 1 shown in FIG. 1 executing a system program and controlling the operations of each part of the control device 1.

[0040] In addition to the analysis unit 100, the smoothing processing unit 110, the low-pass filter unit 112, the inward rotation amount calculation unit 114, and the motor control unit 120, the control device 1 of the present embodiment further includes a pull-back correction unit 116. Further, a control program 200 for controlling the operation of the industrial machine 2 in advance is stored in the RAM 13 to the non-volatile memory 14 of the control device 1.

[0041] The functions provided in the analysis unit 100, the low-pass filter unit 112, the inward rotation amount calculation unit 114, and the motor control unit 120 are the same as the functions provided in the control device 1 according to the first embodiment. The smoothing processing unit 110 according to the present embodiment generates a smoothing curve by correcting, by the pull-back correction unit 116, the smoothing path in which inward rotation has occurred for a plurality of command points in a direction opposite to the inward rotation direction. In other words, it corrects in a direction opposite to the curvature center direction vector (principal normal vector) of the smoothing path. In this specification, correcting in a direction opposite to the inward rotation direction is referred to as pull-back correction.

[0042] The retraction correction unit 116 generates a smoothed curve obtained by performing retraction correction on the smoothed path generated by the smoothing processing unit 110. The retraction correction unit 116 may perform retraction correction using, for example, the inward rotation amount calculated by the inward rotation amount calculation unit 114 as it is. For example, let the center of curvature at each position of the smoothed curve Q(t) be QC(t). In this case, the curvature unit vector eq(t) can be expressed by Equation 6 below.

[0043]

Equation

[0044] In this case, the retraction vector h(t) can be calculated by Equation 7 below.

[0045]

Equation

[0046] Then, the retraction correction unit 116 can calculate the smoothed curve S(t) after retraction correction by Equation 8 below.

[0047]

Equation

[0048] The smoothing processing unit 110 outputs the smoothed curve S(t) after retraction correction obtained in this way to the motor control unit 120 as the final path.

[0049] The retraction correction unit 116 may perform a smoothing process as shown in Equation 9 below when calculating the retraction vector h(t). In Equation 9, F(l) represents a filter operation by a low-pass filter, and l is a parameter representing the application range (filter length) of the filter. This filter F(l) may be the same as the filter used by the low-pass filter unit 112 or different.

[0050] [Number]

[0051] According to one aspect of the present disclosure having the above configuration, the amount of inward rotation by the low-pass filter can be calculated, and the smoothing curve can be corrected using the calculated amount of inward rotation. Therefore, a smooth and highly accurate (without accuracy degradation due to inward rotation) path can be obtained. As a result, a processed workpiece with a smooth processed surface and no deterioration in shape accuracy can be obtained.

[0052] FIG. 5 shows, as a schematic block diagram, the functions provided in the control device 1 according to the third embodiment of the present invention. Each function provided in the control device 1 according to the present embodiment is realized by the CPU 11 provided in the control device 1 shown in FIG. 1 executing a system program and controlling the operations of each part of the control device 1.

[0053] In addition to the analysis unit 100, the smoothing processing unit 110, the low-pass filter unit 112, the inward rotation amount calculation unit 114, and the motor control unit 120, the control device 1 according to the present embodiment further includes a pre-retraction correction unit 118. In addition, a control program 200 for controlling the operation of the industrial machine 2 in advance is stored in the RAM 13 to the non-volatile memory 14 of the control device 1.

[0054] The functions provided in the analysis unit 100, the low-pass filter unit 112, the inward rotation amount calculation unit 114, and the motor control unit 120 are the same as those provided in the control device 1 according to the first embodiment. The smoothing processing unit 110 according to the present embodiment generates correction points corrected in the direction opposite to the inward rotation direction by the pre-retraction correction unit 118 for a plurality of command points before performing the smoothing processing. Then, the low-pass filter unit 112 smooths the plurality of correction points to generate a smoothing curve.

[0055] The pre-retraction correction unit 118 performs pre-retraction correction on a plurality of command points before the smoothing process. Hereinafter, a method for performing pre-retraction correction will be described. Let the command path be a parametric curve P(t), and the radius of curvature at each position thereof be RP(t). When the path is given by a minute line segment, P(t) becomes polygonal. In this case, instead of obtaining the curvature locally, the curvature is obtained from the average shape information in a certain range. Generally, the curvature at each position can be obtained by using polynomial fitting or the like. For example, assuming that an arc path with a radius R is represented by Circle(R), the amount of inward rotation can be calculated by the following Equation 10.

[0056]

Equation

[0057] Also, let the center of curvature at each position of P(t) be PC(t). The curvature unit vector ep(t) in this case can be expressed by the following Equation 11.

[0058]

Equation

[0059] Using d(t) and ep(t) obtained in this way, the pre-retraction vector h pre (t) can be calculated by the following Equation 12.

[0060]

Equation

[0061] Then, using Equation 13, the pre-retraction vector h pre (t) is used to perform pre-retraction correction on P(t), and the corrected command path S(t) is calculated.

[0062]

Equation

[0063] The smoothing processing unit 110 generates a smoothing curve by smoothing the corrected command path S(t) with a low-pass filter unit 112.

[0064] According to one aspect of the present disclosure having the above configuration, the inward rotation amount is calculated in advance, and the command points are corrected using the calculated inward rotation amount. Then, since smoothing is performed on the corrected plurality of command points, a smooth and highly accurate path (without accuracy degradation due to inward rotation) can be obtained. A reduction in the amount of calculation is also expected as compared with the case where correction is performed after calculating the smoothing curve.

[0065] As described above, the embodiments of the present invention have been described. However, the present invention is not limited only to the examples of the above-described embodiments, and can be implemented in various forms by making appropriate changes. For example, in the above-described embodiment, an example is shown in which a sequence of a plurality of command points is shown as a path by the control program 200. Therefore, the description is based on the premise that the intervals between the command points are minute line segments. However, even when the path between the command points is explicitly specified not only by minute line segments but also by minute arcs, predetermined parametric curves, etc. by the control program 200, the present invention can be applied.

[0066] Also, in the above-described embodiment, each value used for calculating the inward rotation amount is calculated from the command path and the smoothing path. However, for example, the curvature at each part of the command path may be set in advance in association with each block of the control program 200. The process of adding such information can be performed in advance on the CAD / CAM side. By configuring in this way, the calculation load on the control device 1 when performing the smoothing process can be reduced.

[0067] In the above-described embodiment, a smoothing path is generated in one calculation path. However, after generating a smoothing path once, the same process may be repeated to generate a smoothing path. For example, the smoothing path created once is repeatedly smoothed by the smoothing processing unit 110. This process is repeated a plurality of times. And by making the filter length of the low-pass filter used each time shorter, the amount of inward rotation and the amount of pulling back can be reduced, and the accuracy of the path after pulling back can be improved. In this case, for example, as illustrated in FIG. 6, a tolerance check unit 119 may be provided. A predetermined tolerance (allowable error) is set in advance in the tolerance check unit 119. Each time the smoothing process is performed by the smoothing processing unit 110, the tolerance check unit 119 checks whether the amount of change (average change amount or maximum change amount) of the smoothing path with respect to the command path is within the tolerance. And if it does not fall within the tolerance, the smoothing process may be repeated. When using this method, the path output by the pull-back correction unit 116 may be output as the final smoothing path (Second Embodiment), or the output of the low-pass filter unit 112 may be output as the final smoothing path (Second and Third Embodiments).

Explanation of Signs

[0068] 1 Control device 2,4 Industrial machine 5 Network 6 Fog computer 7 Cloud server 11 CPU 12 ROM 13 RAM 14 Non-volatile memory 15,17,18,20 Interface 22 Bus 30 Axis control circuit 40 Servo amplifier 50 Servo motor 70 Display device 71 Input device 72 External device 100 Analysis Unit 110 Smoothing Processing Unit 112 Low-Pass Filter Unit 114 Inner Rotation Amount Calculation Unit 116 Pullback Correction Unit 118 Pre-Pullback Correction Unit 119 Tolerance Check Unit 120 Motor Control Unit 200 Control Program

Claims

1. A control device for controlling the processing of a workpiece by an industrial machine based on a control program, comprising: a low-pass filter unit that generates a smoothed path by performing smoothing on a commanded path commanded by the control program using a low-pass filter; an inward rotation amount calculation unit that calculates an inward rotation amount of the smoothed path obtained by the low-pass filter unit in a direction of inward rotation with respect to the commanded path based on a curvature of the commanded path and a filter length of the low-pass filter; a smoothing processing unit that outputs a path in which the smoothed path is pulled back in a direction opposite to the inward rotation direction based on the inward rotation amount; A control device comprising the above.

2. The smoothing processing unit: comprises a pulling-back correction unit that corrects the smoothed path generated by the low-pass filter unit by pulling it back in a direction opposite to the inward rotation direction by the amount of inward rotation calculated by the inward rotation amount calculation unit; Outputs the path corrected by the pulling-back correction unit. The control device according to Claim 1.

3. The smoothing processing unit: comprises a pre-pulling-back correction unit that corrects the commanded path by pulling it back in a direction opposite to the inward rotation direction by the amount of inward rotation calculated by the inward rotation amount calculation unit in advance; Outputs a smoothed path obtained by smoothing the commanded path corrected by the pre-pulling-back correction unit using the low-pass filter unit. The control device according to Claim 1.

4. The inward rotation amount calculation unit uses the difference between the commanded path and the smoothed path as the inward rotation amount. The control device according to Claim 1.

5. The inward rotation amount calculation unit calculates the inward rotation amount based on the difference between a plurality of command points commanded by the control program and the smoothed path. and so on. The control device according to Claim 1.

6. The curvature of the commanded path is calculated using the curvature of the smoothed path. The control device according to Claim 1.

7. The curvature of the commanded path is specified as information associated with the control program. The control device according to Claim 1.

8. The filter length is calculated based on at least one of a moving speed along the commanded path and a time constant of the low-pass filter. The control device according to Claim 1.

9. The smoothing processing unit repeatedly performs smoothing processing on the output path using the inward rotation amount calculation unit and the low-pass filter unit. The control device according to claim 1.

10. further comprising a tolerance check unit that checks whether the path change amount is within a specified tolerance; the smoothing processing unit repeatedly performs smoothing processing until the path change amount becomes within the specified tolerance by the tolerance check unit; The control device according to claim 9.

11. A computer-readable recording medium recording a program for operating a control device that controls the processing of a workpiece by an industrial machine based on a control program, a low-pass filter unit that generates a smoothed path by performing smoothing on a commanded path commanded by the control program using a low-pass filter; an inward rotation amount calculation unit that calculates an inward rotation amount in a direction of inward rotation with respect to the commanded path of the smoothed path obtained by the low-pass filter unit based on the curvature of the commanded path and the filter length of the low-pass filter; a smoothing processing unit that outputs a path in which the smoothed path is pulled back in a direction opposite to the inward rotation direction based on the inward rotation amount; A computer-readable recording medium recording a program for operating a control device.

Images