JP2005227971A - Cycle time arithmetic device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a cycle time arithmetic device calculating positioning data operating in a cycle time by designating the desired cycle time, in a PLC or the like. <P>SOLUTION: This cycle time arithmetic device has: a mouse 106a or a keyboard 106b of a personal computer 104 for inputting the desired cycle time when a cycle time calculated on the basis of the inputted positioning data is not a desired value; a positioning data setting device 105 calculating the positioning data corresponding to the desired cycle time on the basis of the inputted desired cycle time; and a cycle time calculation result display screen 709 displaying a calculated arithmetic result. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to setting of positioning data of a positioning unit in a programmable logic controller (hereinafter referred to as “PLC” as appropriate), positioning operation time for positioning operation (hereinafter referred to as “tact time” as appropriate), and desired The present invention relates to a tact time calculation device that calculates positioning data for operation with a tact time of the same.

A conventional tact time calculation device is mainly used in a robot operation program creation device, and is a technique for obtaining a tact time required for operating a robot. It has a function to calculate the shortest movement time of the robot from movement information (movement distance, movement speed, acceleration) inputted in advance.
In the conventional apparatus, there is no independent designation of deceleration, and acceleration and deceleration are treated as the same. The acceleration referred to here is the amount of change until the moving speed with respect to the actual acceleration time is reached (see, for example, Patent Document 1).

JP-A-4-260104 (page 2-3)

Many of the conventional tact time calculation techniques described above are directed to robot operations. When positioning control is performed in a positioning unit in a PLC, movement information (PLC) of a desired operation is determined by a positioning data setting device. However, it is necessary to keep the time for the actual positioning operation by the created positioning data, that is, the tact time within a certain range. For this reason, it is necessary to know the tact time of the set positioning data. At present, however, the positioning data can be calculated manually or created based on the knowledge obtained from experience values and actually operated. Measuring and checking.
However, when the calculation formula is complicated and there are a plurality of positioning data (in the positioning unit in the PLC, positioning data of 600 patterns can be set), it takes a lot of work. In order to actually perform the operation, it is necessary to prepare an environment and an apparatus capable of positioning operation.
That is, there is a problem that it takes a lot of labor and time to know the tact time of the created positioning data.

Further, in the calculation of the conventional apparatus, it is assumed that the movement information regarding acceleration / deceleration is input only by acceleration and the deceleration is the same as the acceleration in calculating the tact time.
Therefore, there is a problem that it cannot be applied when acceleration and deceleration are different as in a positioning unit in PLC.

Furthermore, in addition to knowing the tact time of the positioning data that was actually created, if the tact time was not the desired tact time, the positioning data was changed to operate at the desired tact time. There is a need to. Therefore, positioning data that operates at a desired tact time is obtained by changing each item value of the positioning data and repeatedly performing the work of calculating the tact time.
At present, the positioning data items that can be changed include items that can be changed depending on the status of the system and the user, and items that cannot be changed. When there are a plurality of items that can be changed, it is necessary to change and calculate each item value. Therefore, the change and calculation are repeated many times, which is troublesome and takes time.

  The present invention has been made to solve such problems, and relates to the setting of the positioning unit in the PLC, and by specifying the tact time for the operation by the input positioning data and the desired tact time. A tact time calculation device for calculating positioning data operating at the tact time is obtained.

  A tact time calculation device according to the present invention includes a tact time input means for inputting a desired tact time, and positioning data for calculating positioning data corresponding to the desired tact time based on the input desired tact time. A data calculation unit and a display unit for displaying the calculated calculation result;

  Also, a tact time calculation means for calculating a tact time based on the input positioning data, and a desired tact time is input when the tact time calculated based on the input positioning data is not a desired value. Tact time input means, positioning data calculation means for calculating positioning data corresponding to the desired tact time based on the inputted desired tact time, and display means for displaying the calculated calculation result It is equipped with.

  The positioning data is composed of a plurality of items.

  The positioning data items include acceleration time and deceleration time that can take a value independent of this acceleration time.

  In order to calculate the desired tact time by the positioning data calculation means, input of whether or not each item of positioning data can be changed is checked in a check box displayed on the screen of the display means. Is what you do.

  Furthermore, when a plurality of positioning data items can be changed, the priority for changing each item of the plurality of positioning data that can be changed is the order in which the check boxes are checked. It is in accordance with.

  According to the present invention, it is possible to calculate the tact time from the positioning data set by the positioning data setting function of the positioning unit in the PLC, and conversely, the tact time once calculated is desired. If the tact time is not reached, the desired tact time can be re-input to obtain positioning data for operating at that tact time.

Embodiment 1 FIG.
A tact time calculation device according to an embodiment of the present invention will be described with reference to FIGS.
In this embodiment, the tact time is calculated from the positioning data set by the positioning data setting device of the positioning unit in the PLC, and if the calculated result is not the desired tact time, the desired time is calculated. On the contrary, a function for obtaining positioning data that operates at the inputted desired tact time by inputting the tact time will be described.

First, the positioning of the positioning unit and positioning data setting device in the PLC will be described with reference to FIG.
In FIG. 1, reference numeral 101 denotes a PLC CPU unit, and reference numeral 102 denotes a PLC positioning unit, which operates according to a command from the CPU unit 101. Reference numeral 105 denotes a positioning data setting device for the positioning unit, which sets movement information for operating the positioning unit 102. The positioning data setting device 105 of this embodiment is software (S / W), operates on the personal computer 104, and transmits the set movement information to the communication cable 103 and the CPU unit 101. Is transferred to the positioning unit 102.
In this embodiment, the positioning data setting device 105 has both functions of a tact time calculation means and a positioning data calculation means.

  Next, a function for calculating the tact time from the positioning data set by the positioning data setting device of the positioning unit in the PLC will be described.

First, the basic concept of the calculation for calculating the tact time from the positioning data in this embodiment will be described with reference to FIG.
The horizontal axis is time, and the vertical axis is moving speed. The “movement distance” of one positioning data has a trapezoidal area as shown in FIG. The tact time (positioning operation time) to be obtained is the value of the bottom of the trapezoid. If the “command speed”, “actual acceleration time”, “actual deceleration time”, and “movement distance” are determined, the tact time that is the base is calculated by an equation for obtaining the area of the trapezoid.
However, when the “movement distance” is short, there is a case where the vehicle must decelerate and stop before reaching the “command speed” (FIG. 5). In this case, the tact time is calculated from an equation for obtaining the area of the triangle.
Furthermore, as shown in FIG. 6, when the vehicle decelerates and stops when the “command speed” is reached, the tact time is obtained by adding the actual acceleration time and the actual deceleration time without the need for obtaining the area. Become.
Therefore, the tact time is calculated when there is a constant speed time (Fig. 4), when there is no constant speed time and the vehicle does not reach the command speed (Fig. 5), and there is no constant speed time, When decelerating when reaching the speed (FIG. 6), the three patterns are obtained.

Next, a series of procedures for calculating the tact time using the above concept will be described with reference to FIG. FIG. 2 is a flowchart of a series of procedures for calculating the tact time. FIG. 3 is a table of a series of calculation formulas for calculating the tact time by the tact time computing device of this embodiment, which the positioning data setting device 105 has.
Here, variables used in the calculation are defined. As shown in FIGS. 4 to 6, the actual acceleration time is t1, the command speed is V, the speed limit value Vmax, the acceleration time is T1, the actual deceleration time is t2, the deceleration time is T2, the travel distance is L, the tact time ( Positioning operation time) is T.

  In FIG. 2, first, as shown in step 201, desired positioning data for positioning by the positioning unit is set by the positioning data setting device. Positioning data to be set includes “movement distance”, “speed limit value”, “command speed”, “acceleration time”, and “deceleration time”.

Next, in step 202, data "actual acceleration time" and "actual deceleration time" necessary for calculating the tact time are calculated.
The tact time is calculated by the positioning data setting device, but the data set in step 201 does not have “actual acceleration time” and “actual deceleration time” (the actual acceleration time is not detected in the positioning unit in the target PLC). (There is no specification of time and actual deceleration time). Therefore, “actual acceleration time” and “actual deceleration time” are calculated next. The “actual acceleration time” is the time required to reach the “command speed” when operating at an acceleration that reaches the “speed limit value” in the “acceleration time”, and the trapezoidal inclination shown in FIGS. 4 to 6 is obtained. It can be obtained by an expression.
First, when the actual acceleration time is calculated, V / t1 = Vmax / T1 as shown in Equation 301 of FIG.
Therefore, t1 = V * T1 / Vmax.
Similarly, the actual deceleration time is V / t2 = Vmax / T2 from the equation for obtaining the slope.
Therefore, t2 = V * T2 / Vmax.

In steps 203 and 204 in FIG. 2, a pattern for calculating the tact time is determined.
As described above, there are three patterns for calculating the tact time. Therefore, it is necessary to divide the pattern operation for the set data. In the case classification method, the “movement distance” is calculated on the assumption that the set data corresponds to the pattern of FIG. Since the pattern in FIG. 6 is a triangular pattern with no constant speed time, it is applied to an equation for calculating the area of the triangle (Equation 302 in FIG. 3). When the result (Equation 301 in FIG. 3) calculated in Step 202 in FIG. 2 is applied to t1 and t2 in Equation 302 in FIG.
((V * T1 / Vmax) + (V * T2 / Vmax)) * V) / 2.
In step 201 of FIG. 2, the pattern is determined by comparing the size with the “movement distance L” set by the positioning data setting device. If the set “movement distance” is larger, it means that the movement is further than the “movement distance” of the pattern of FIG. On the other hand, when the set “movement distance” is smaller, the pattern shown in FIG. 5 is obtained.

  In Steps 205, 206, and 207 in FIG. 2, all the patterns and data for calculating the tact time have been prepared, so the tact time is actually calculated.

Step 205 in FIG. 2 is the pattern in FIG. 4 (when a constant speed time exists). In the pattern of FIG. 4, the tact time is calculated by applying to the formula for obtaining the trapezoid area.
Therefore, (((T− (t1 + t2)) + T) * V) / 2. Applying the result calculated in step 202 in FIG. 2 (equation 301 in FIG. 3) to t1 and t2 ((T + (T − ((V * T1 / Vmax) + (V * T2 / Vmax)))) * V) / 2. If this equation is tact time (positioning operation time) T,
T = (L / V) + ((V * T1) / (2 * Vmax)) + ((V * T2) / (2 * Vmax)) (Equation 303 in FIG. 3).

Step 207 in FIG. 2 corresponds to the pattern in FIG. 5 (when there is no constant speed time). In the pattern of FIG. 5, the tact time is calculated by applying to the formula for obtaining the area of the triangle. However, since the vehicle does not reach the command speed and decelerates, it is necessary to calculate the actual moving speed.
Therefore, the actual moving speed is obtained. Assume that the actual moving speed is v, and the time to reach the actual moving speed is tt1. (V / tt1) = (Vmax / T1), (v / (T−tt1)) = (Vmax / T2) according to the formula for obtaining the inclination of the triangle.
Therefore, the actual moving speed v is (Vmax / T2) * (T − ((T1 * v) / Vmax)).
Since the formula for obtaining the area of the triangle is (T * v) / 2 = L, the moving speed v calculated above is substituted, and the tact time T is ((2 * L * (T1 + T2)) / Vmax) (Equation 304 in FIG. 3).

Step 206 of FIG. 2 is the pattern of FIG. 6 and there is no constant speed time, but the speed reaches the command speed and the vehicle is decelerated. Therefore, the tact time is obtained by adding the actual acceleration time and the actual deceleration time. Therefore, the tact time is obtained by adding the results (expression 301 in FIG. 3) t1 and t2 calculated in step 202 in FIG.
That is, T = (V * T1 / Vmax) + (V * T2 / Vmax) (Equation 305 in FIG. 3).

  The positioning data sets one operation as one data. Therefore, there are cases where a plurality of data are continuously operated to complete a series of operations. Since the above-mentioned idea is one operation (one data), it is possible to calculate all tact times in a series of operations by calculating and adding a plurality of data.

In the above description, the single-axis operation is described as an example. However, the present invention is not limited to this, and the present invention can be applied to a case where a movement distance in each axial direction is given (in the case of interpolation control).
In the case of this interpolation control, an interpolation movement distance may be obtained from the movement distance of each axis based on the three-square theorem and applied as the movement distance (Equation 306 in FIG. 3).

In accordance with the above-described procedure, the tact time can be calculated from the movement information set by the positioning data setting device for the positioning unit in the PLC. Therefore, it is not necessary to prepare an actual device or environment for operation, which is a conventional problem. Further, since the confirmation after the adjustment of the positioning data can be performed without using the apparatus, the time for creating the positioning data can be shortened.
Further, the acceleration time and deceleration time of the set data can be used to calculate the case where the acceleration and the deceleration that cannot be calculated by the conventional apparatus are different.

Next, an operation procedure for changing the tact time once obtained by the tact time computing device of this embodiment and obtaining positioning data operating at a desired tact time will be described with reference to FIG.
In FIG. 7, reference numeral 701 denotes a positioning data setting screen in the positioning data setting device for performing the tact time calculation process of the present invention. Reference numerals 702 to 707 are basically necessary positioning data in the position control of the positioning device. As shown in the item field 708, the positioning data of 702 to 707 are set as a group, and a plurality of rows are set in order from No1. It is possible.

First, the user sets positioning data 702 to 707 on the screen 701 in FIG. Next, by clicking any No. row in the column 708 with the mouse 106a shown in FIG. 1, the positioning data for which the tact time is to be calculated is selected. After that, by selecting “tact time calculation menu” in the right-click menu or pull-down menu, the tact time calculation function of the positioning data setting device 105 is changed to the tact time using the selected positioning data. Perform the calculation process.
The calculation result is displayed on the calculation result display unit 710 of the positioning operation time on the tact time calculation result display screen 709 in FIG.
If the user confirms the calculation result and the tact time is not the desired one, the mouse 106a of the personal computer 104 shown in FIG. A desired tact time is input into the calculation result display unit 710 using the terminal 106b or the like, and positioning data that operates at the desired tact time is obtained.
In order to obtain this positioning data, the value of each item of positioning data is changed within the setting range that can be taken for each item based on the selected positioning data of No, and the desired tact time is obtained. Find the positioning data that operates in.

However, the items of positioning data that can be changed vary depending on the user, and there are cases where there is an item that is not particularly desired to be changed. Further, when all items are changed, the positioning data becomes a huge pattern. The positioning data to be changed is four items of “acceleration time”, “deceleration time”, “positioning address”, and “command speed”. If all of these items are subject to change, the acceleration time is 4 patterns, the deceleration time is 4 patterns, and the positioning address and command speed have continuous values with a certain range as input values. Exists, for example, in the range of 0-2147483647. Therefore, the number of patterns that can be considered is a pattern number close to infinity. For this reason, it is very difficult for the user to find the positioning data that meets his needs from the positioning data pattern obtained.
Therefore, the obtained positioning data pattern is provided in a narrowed form according to the user's needs.

First, an item that can be changed is selected from among the items of positioning data. This selection can be made by the check boxes of acceleration time 712, deceleration time 713, positioning address 714, and command speed 716 in FIG. Since the positioning address and the command speed have a setting range, input areas 715 and 717 are prepared, and desired numerical values can be input within a changeable range. Since the acceleration time and the deceleration time are a selection formula from four patterns of patterns 1, 2, 3, and 4, it is not possible to freely set numerical values.
Furthermore, it is possible to provide positioning data as necessary by giving priority (priority) in the change order to a plurality of changeable items. The priority order of the change order is set in the order in which the check boxes are checked, and the priority order is displayed next to the check boxes in the order in which the check boxes are checked. When all the desired items are selected and the adjustment button 711 is pressed, the positioning data adjusted for the desired tact time and the changeable items are calculated, and the positioning data shown in FIG. Are provided in a list display 718. A list of positioning data is displayed from the positioning data adjusted in the items with high priority.

Next, adjustment processing of positioning data that operates at a desired tact time will be described with reference to FIGS.
FIG. 8 is a flowchart of a series of procedures for adjusting positioning data from the tact time.

First, in step 801 in FIG. 8, the tact time is calculated based on the positioning data set by the user on the positioning data setting screen 701 in FIG. 7A, and the calculation result is shown in FIG. It displays on the calculation result display part 710 of the screen 709 of b).
In step 802, the user checks whether the tact time of the displayed calculation result is a desired tact time. If it is not the desired tact time, the desired tact time is input again to the calculation result display unit 710 in FIG.

  After inputting the desired tact time, in step 803, positioning data that may be changed among the check box items of acceleration time 712, deceleration time 713, positioning address 714, command speed 716 shown in FIG. -Select the item. Also, priorities are set for the items that can be changed in the selection order at this time. Further, in step 804 of FIG. 8, a changeable range is input and set to items that can be changed in the input areas 715 and 717 of FIG.

  Positioning data adjustment processing is performed on the basis of a desired tact time by the user, positioning data that can be changed, and the setting of the range.

When there is only one type of positioning data item that can be changed, it can be calculated using the tact time calculation formula (formula 303, 304, and 305 in FIG. 3) described above. The previous calculation formula derives the tact time, but on the contrary, the positioning data items that can be changed can be back calculated based on the input and set tact time.
As the positioning data items that can be changed, as described above, the possible range (changeable range) is determined in advance, and if it is within that range, the positioning data adjustment result is shown in FIG. ) Is displayed on the screen of the positioning data list display 718 shown in FIG. If it does not fall within that range, a message indicating that data that fits in the desired tact time cannot be created with the selected positioning data item is displayed, and the positioning data that can be changed again is displayed to the user. -Prompt to select the item.

If there are multiple types of positioning data items that can be changed, calculation is performed using equations 303, 304, and 305 in FIG. 3 as in the case of one item. It is not data. Therefore, all combinations of possible ranges (ranges that can be changed) within the range of positioning data that can be changed are substituted into the calculation formula, and the combinations that are formed as formulas are positioned as shown in FIG. 7C as positioning data adjustment results. The data list display 718 is displayed on the screen. The item of positioning data that can be changed at this time is changed from the item with the highest priority, and the adjustment result is displayed in order from the positioning data adjusted with the item with the higher priority.
If there is no combination that holds as an expression, data that fits in the desired tact time is created in the selected changeable positioning data item, as in the case of one changeable positioning data item. A message indicating that it is not possible is displayed, and the user is prompted to select an item of positioning data that can be changed again.

Details of the adjustment method and the result display method when there are a plurality of changeable positioning data items will be described with reference to FIG.
In FIG. 9, reference numeral 901 denotes a table of items to be adjusted and the number of calculations. Reference numeral 915 denotes a positioning data list as an adjustment result. In order to change from the one with the highest priority, the first adjustment is made by changing only the item of priority 1 as shown in the first row 902. The adjustment is to change the priority level 1 item within a possible range (changeable range) and substitute the calculation into a tact time calculation formula (formula 303, 304, and 305 in FIG. 3). If there is a combination that holds as an expression, positioning data 916 to which the value after the change of priority 1 is applied is displayed.
In the second time, as shown in the second row 903, adjustment is performed by a combination of items of priority 2 and priority 1 having the next highest priority. As in the first time, the priority order items 1 and 2 are changed within a possible range, and are substituted into the tact time calculation formula. If there is a combination that holds as an expression, positioning data 917 to which the values after the change of the priorities 1 and 2 are applied is displayed.
In this way, adjustments are made in the order of the item rows 902 to 914 in the order of the combination of items that can be changed preferentially (high priority) selected and set by the user. A certain positioning data list 915 is displayed from the first line.

As described above, according to the embodiment, the positioning data set by the positioning data setting device of the positioning unit in the PLC is changed to the positioning data that operates at a desired tact time. Can be adjusted and provided.
Furthermore, even when there are a plurality of positioning data that can be provided, the positioning data can be provided in order from the required positioning data.
Therefore, it is possible to obtain an effect that the creation time of the positioning data can be shortened.

BRIEF DESCRIPTION OF THE DRAWINGS Schematic for demonstrating the positioning unit and positioning data setting apparatus in PLC by embodiment of this invention. A flow chart of a series of procedures for calculating the tact time by the tact time computing device of the embodiment of the present invention. The table | surface of a series of calculation formulas which calculate the tact time by the tact time calculating apparatus of embodiment of this invention. Explanatory drawing for calculating | requiring the movement distance by positioning data when constant speed time exists. Explanatory drawing for calculating | requiring the movement distance by positioning data when decelerating without reaching constant speed time and not reaching command speed. Explanatory drawing for calculating | requiring the movement distance by positioning data in the case of decelerating when the constant speed time does not exist and it reaches to the command speed. The figure of the positioning data setting screen in the positioning data setting apparatus which performs the tact time calculation process by the tact time calculating apparatus of the embodiment of the present invention. A flow chart of a series of procedures for adjusting positioning data from the tact time by the tact time arithmetic unit according to the embodiment of the present invention. FIG. 5 is a table of items to be adjusted and the number of calculation times by the tact time calculation device according to the embodiment of the present invention, and a positioning data list which is an adjustment result corresponding to the table.

Explanation of symbols

104 Personal Computer 105 Positioning Data Setting Device 106a Mouse 106b Keyboard 709 Tact Time Calculation Result Display Screen 712, 713, 714, 716 Check Box

Claims (6)

A tact time input means for inputting a desired tact time;
Positioning data calculating means for calculating positioning data corresponding to the desired tact time based on the input desired tact time;
Display means for displaying the calculated calculation results;
A tact time calculation device comprising: A tact time calculating means for calculating a tact time based on the input positioning data;
Tact time input means for inputting a desired tact time when the tact time calculated based on the input positioning data is not a desired value;
Positioning data calculating means for calculating positioning data corresponding to the desired tact time based on the input desired tact time;
Display means for displaying the calculated calculation results;
A tact time calculation device comprising:   3. The tact time calculation apparatus according to claim 1, wherein the positioning data includes a plurality of items.   4. The tact time calculation device according to claim 1, wherein the positioning data items include an acceleration time and a deceleration time that can take a value independent of the acceleration time.   In order to calculate a desired tact time by the positioning data calculation means, whether or not each item of the positioning data can be changed is input by checking a check box displayed on the screen of the display means. The tact time calculation device according to any one of claims 1 to 4, wherein   When changes can be made to multiple positioning data items, the priority for changing each of the multiple positioning data items that can be changed depends on the order in which the check boxes are checked. The tact time calculation device according to claim 5, wherein

Images