JP7172138B2 - Information processing device, time estimation method and time estimation program - Google Patents

Description

The present invention relates to an information processing device, time estimation method, and time estimation program.

2. Description of the Related Art Conventionally, in work organization that allocates work to each process of an assembly line that assembles products, optimization is performed in consideration of observance of the work order in each process, leveling of the work amount, and the like. Since this optimization process is difficult to perform manually, techniques for providing operators with information on work organization considerations and techniques using various algorithms have been proposed.

When each process of an assembly line includes a process to be performed by a working robot, there is known a technique for generating a robot program for teaching the working robot how to operate by using a three-layered robot operation template. there is

JP-A-2002-292467 JP-A-2003-39260

Robot motion templates with a three-level configuration can be used to describe the motion of the robot. However, in the case of relatively difficult work such as assembly work of small electronic devices (for example, notebook PC), work of assembling parts, work of pasting flexible materials such as tape, work of running cables, etc. may require feedback control. Generally, if feedback control is performed, more time is required than if it is not performed, but in the present situation, it is not possible to accurately estimate the time required for feedback control.

In one aspect, an object of the present invention is to provide an information processing device, a time estimation method, and a time estimation program capable of accurately estimating the time required for feedback control.

In one aspect, the information processing device acquires tolerance information of a first part and tolerance information of a second part to which the first part is assembled from a first storage unit that stores tolerance information of the parts. and a second acquisition unit that acquires the repeated positional accuracy of the robot that assembles the first part to the second part from a second storage that stores the repeated positional accuracy of the robot. a calculating unit for calculating a maximum number of times of feedback control that needs to be performed during assembly based on the acquired tolerance information and the repeatable position accuracy ; and a calculated maximum number of times of feedback control. and an estimating unit for estimating the time required when the feedback control is performed the number of times of the maximum value based on.

It is possible to accurately estimate the time required for feedback control.

1 is a diagram schematically showing the configuration of an information processing device according to an embodiment; FIG. 3 is a functional block diagram of an information processing device; FIG. It is a figure which shows an example of the data structure of work information DB. FIG. 4(a) is a diagram showing an example of the data structure of the design information DB, and FIG. 4(b) is a diagram showing an example of the data structure of the facility information DB. FIG. 4 is a diagram for explaining tolerances between an attachment part and an attachment destination part; 5 is a flow chart showing processing of a maximum number of corrections calculation unit and a correction time calculation unit; FIG. 10 is a diagram showing a load table when feedback control time is not included; FIG. 10 is a diagram for explaining a variation range σ; FIG. 11 is a diagram (part 1) showing a load table when feedback control time is included; FIG. 11 is a diagram (part 2) showing a load table when feedback control time is included;

An embodiment of an information processing apparatus will be described in detail below with reference to FIGS. 1 to 10. FIG.

FIG. 1 shows the hardware configuration of an information processing device 10 according to one embodiment. The information processing apparatus 10 of this embodiment is, for example, a PC (Personal Computer), and as shown in FIG. , a storage unit (here, HDD (Hard Disk Drive)) 96, a network interface 97, a portable storage medium drive 99, a display unit 93, an input unit 95, and the like. The display unit 93 includes a liquid crystal display and the like, and the input unit 95 includes a keyboard, mouse, touch panel and the like. Each component of the information processing apparatus 10 is connected to the bus 98 . In the information processing apparatus 10, the program (including the time estimation program) stored in the ROM 92 or the HDD 96 or the program (including the time estimation program) read from the portable storage medium 91 by the portable storage medium drive 99 is executed by the CPU 90. , the functions of the units shown in FIG. 2 are realized. 2 also shows a work information DB (database) 21, a design information DB 22, and an equipment information DB 23 stored in the HDD 96 of the information processing apparatus 10. As shown in FIG. The portable storage medium 91 is, for example, a CD-ROM, a DVD disk, a portable storage medium such as a USB (Universal Serial Bus) memory, or a semiconductor memory such as a flash memory.

FIG. 2 is a functional block diagram of the information processing device 10. As shown in FIG. In the information processing apparatus 10, the CPU 90 executes a program to provide an input unit 11, a process plan formulation unit 12 as a formulation unit, a maximum correction number calculation unit 13, a correction time calculation unit 14, and A function as the robot program generation unit 15 is realized. Note that the function of each unit in FIG. 2 may be implemented by an integrated circuit such as an ASIC (Application Specific Integrated Circuit) or an FPGA (Field Programmable Gate Array).

The information processing device 10 uses the data in each of the DBs 21, 22, and 23 when starting up an assembly line (manufacturing line) or when it becomes necessary to organize the assembly line due to production fluctuations, resource fluctuations, or the like. , to assign work to each process. Further, the information processing apparatus 10 generates a robot program for causing the robot to execute the work assigned to the process in which the robot is arranged, and inputs the robot program to the robot.

In this embodiment, the assembly line conveys products from process to process by a belt conveyor (not shown) or the like. A human or a robot system is placed in each process of the assembly line. A person or a robot system placed in each process carries out the work assigned by the process plan to the products transported in the assembly line to manufacture the products. Note that the number of people and robot systems is arbitrary. Therefore, the number of robot systems may be one or plural.

Functions of the information processing apparatus 10 will be described below.

The input unit 11 receives input from the manager, reads work information from the work information DB 21 based on the input, and transmits the work information to the process plan formulation unit 12 . Here, it is assumed that work information as shown in FIG. 3 is stored in the work information DB 21 . In the example of FIG. 3, the information of the fitting work is shown, and the information of the fitting work consists of the information of the details of the work when the subject of the work is a human and the information of the details of the work when the subject of the work is a robot. contains. The information of each work has a three-level structure including work, elemental work, and action.

When the subject of work is a person, the information includes work type and ΣHT (work time) information, element work information, and tool information. and the time (HT) required for each element work. For example, the fitting operation in FIG. 3 includes “grasping” and “fitting” as elemental operations, and the time required for the elemental operations “grasping” and “fitting” is 1.5 seconds and 2.2 seconds, respectively. It's becoming Also, the element work "grasping" includes the actions "arm movement" and "grasping", and the time required for each action is 0.7 seconds and 0.8 seconds. Furthermore, the element work "fitting" includes the motions "arm movement" and "fitting", and the time required for each motion is 0.7 seconds and 1.5 seconds.

In addition, information when the subject of work is a robot includes work type, ΣMT (work time) information, element work information, and tool information. and information on the time required for operation, the presence or absence of interference, and the time required for each element work (MT). For example, the fitting operation in FIG. 3 includes “grasping”, “installation”, and “retraction” as elemental operations, and the time required for the elemental operations “grasping”, “installation”, and “retraction” is 3 seconds and 4 seconds, respectively. seconds, 1 second. Also, the element work "grasping" includes actions "Move" and "Pic", and the time required for each action is 1 second and 2 seconds. Also, the element work "installation" includes the operations "Transfer" and "Place", and the time required for each operation is 1 second and 3 seconds. Furthermore, the elemental work 'retreat' includes the action 'MoveHome', and the time required for the action is 1 second. Here, "FB" is described in the operation "Place" of the element work "Installation", and it is defined that feedback control can be executed.

Returning to FIG. 2 , the process planning section 12 allocates each work to each process based on the work information received from the input section 11 . In this case, the process plan formulation unit 12 considers a plurality of parameters such as parameters related to workability of people and robots, and uses a local search method such as a tabu search or simulated annealing method to Assign work. The parameters include, for example, parameters such as time variation between processes and whether or not the same tool can be integrated into a specific process.

The maximum number of times of correction calculation section 13 calculates the maximum number of times of correction for an operation in which feedback control is possible. When calculating the maximum number of times of correction, the maximum number of times of correction calculation section 13 uses information stored in the design information DB 22 as the first storage section and the equipment information DB 23 as the second storage section.

Here, the design information DB 22 includes, as shown in FIG. 4(a), variation information of parts to be attached and variation information of parts to be attached. The information on the variation of the parts to be assembled stores information on the "outer dimensions of the parts to be assembled" and the "outer shape tolerance" in association with the "name of the parts to be assembled". For example, assuming that parts (Parts_A) are assembled to parts (Parts_B), as shown in FIG. there is In addition, in the variation information of the parts to be assembled, information of "inner dimension of the part to be assembled" and "shape tolerance of the part to be assembled" is stored in association with the "name of the part to be assembled". For example, assuming that a part (Parts_A) is assembled to a part (Parts_B) as shown in FIG. is stored.

The facility information DB 23 stores robot information as shown in FIG. 4(b). The robot information in FIG. 4(b) includes information of "robot name", "repeated position accuracy", "moving speed", "sensing time", and "determination time" . The moving speed means the speed at which the robot moves. The sensing time means the time required for sensor input to the robot, and the determination time means the time required for the robot to make a decision based on the information input from the sensor. In the example of FIG. 4B, as the information of the robot (Robot_A), the repeat position accuracy Δe, the moving speed vr, the sensing time Ts, and the judgment time Tj are stored.

The correction time calculator 14 calculates the maximum correction time (maximum time required for feedback control) based on the maximum number of corrections calculated by the maximum number of corrections calculator 13 when feedback control is performed. In this case, the correction time calculator 14 calculates the maximum correction time using information stored in the equipment information DB 23 . Further, the correction time calculation unit 14 estimates the work time for each process based on the calculated correction time, and transmits the estimated work time to the robot program generation unit 15 .

The robot program generation unit 15 generates a robot program based on the information received from the correction time calculation unit 14, and transmits the generated robot program to the robot to which the work is assigned.

(Processing of information processing device 10)
Next, the processing of the maximum number of correction times calculation unit 13 and the correction time calculation unit 14 will be described in detail along the flowchart of FIG. 6 and with appropriate reference to other drawings.

As a premise for the processing of FIG. 6, the process plan formulation unit 12 divides the tasks 1 to 4 into human processes and robot processes based on the work information stored in the work information DB 21, as shown in the load table of FIG. shall be allocated. In FIG. 7, operations 1 and 2 are assigned to human processes, and operations 3 and 4 are assigned to robot processes. Note that the load table in FIG. 7 does not show the time required for feedback control in the robot process, and the maximum time required for feedback control (maximum correction time) is calculated by the process according to the flowchart in FIG. It's like

In the process of FIG. 6, first, in step S10, the maximum number of correction calculation unit 13 acquires the information on the variation of the parts and calculates the variation range σ of the combination. For example, it is assumed that work 3 shown in the load table of FIG. 7 is the work of fitting attachment parts Parts_A to attachment destination parts Parts_B. In this case, in order to calculate the maximum correction time of the operation “Place” of the element work “Installation”, the maximum number of correction calculation unit 13 extracts the external shape tolerance “σa” of the attachment parts Parts_A from the design information DB 22 and the attachment destination parts Parts_B and the shape tolerance “σbh” of the assembly portion of . Then, the maximum number of correction calculation unit 13 uses the obtained information to calculate the combination variation range σ (see FIG. 8) based on the following equation (1).

In addition, the variation range σ of the combination is set so that the center of the assembly part of the part to be assembled (Parts_A) (the position indicated by the two-dot chain line in FIG. 8) is the center of the assembly part of the part to be assembled (Parts_B) (the one-dot chain line in FIG. 8). It means the variation range of the amount of misalignment between the centers when an instruction is given to align with the position).

Next, in step S12, the maximum number of correction calculation unit 13 calculates the minimum guaranteed movement amount based on the repeat position accuracy. In this case, assuming that the robot used for the work is Robot_A, the maximum number of correction calculation unit 13 acquires the repeat position accuracy Δe of Robot_A from the facility information DB 23, and calculates the minimum guaranteed movement amount based on the following equation (2). Δr is calculated.
Δr=Δe×2 (2)

In the present embodiment, the amount of movement that the robot can reliably move without error is defined as a distance twice the repeatable positional accuracy, and this distance is defined as the minimum guaranteed movement amount Δr.

Next, in step S14, the maximum number of corrections calculator 13 calculates the maximum number of corrections based on the minimum guaranteed movement amount. In this case, the maximum number of correction calculation unit 13 uses the minimum guaranteed movement amount Δr calculated using the above equation (2) as the position correction amount per one time, and calculates the maximum number of corrections Nmax required for the work from the variation range σ. , is calculated based on the following equation (3).
Nmax=σ/Δr (3)

When σ/Δr is not divisible in the above equation (3) (Nmax is a decimal number), the maximum number of corrections calculation unit 13 may set Nmax as the smallest natural number larger than σ/Δr.

The maximum number of corrections calculation unit 13 transmits the calculated maximum number of corrections Nmax and the position correction amount (minimum guaranteed movement amount) Δr per time to the correction time calculation unit 14 .

Next, in step S16, the correction time calculator 14 calculates the correction time per time. Specifically, the correction time calculation unit 14 acquires the moving speed vr of the robot (Robot_A) to be used, the sensing time Ts, and the determination time Tj from the equipment information DB 23, and calculates the acquired information and the position correction amount Δr per time. , the correction time ΔTc per time is calculated from the following equation (4).
ΔTc=(Δr/vr)+Ts+Tj (4)

Next, in step S18, the correction time calculator 14 calculates the maximum correction time and estimates the work time. Specifically, the correction time calculator 14 calculates the maximum correction time ΔM in each operation from the following equation (5) using the maximum number of times of correction Nmax and the correction time ΔTc per time.
ΔM=Nmax×ΔTc (5)

Then, the correction time calculator 14 adds the calculated maximum correction time ΔM to the work time to estimate the work time when the feedback control is executed. FIG. 9 shows a load table when feedback control is executed. In the example of FIG. 9, the maximum correction time ΔM in the action "Place" of the elementary work "Installation" of the work 3 is the time for four times of feedback control, and the maximum correction time in the action "Place" of the elementary work "Installation" of the work 4 The correction time ΔM is the time for two feedback controls. The correction time calculation unit 14 transmits the load table information as shown in FIG. 9 to the robot program generation unit 15 .

As shown in FIG. 9, the robot program generation unit 15 determines that the robot working time MCT to which the maximum correction time ΔM for feedback control is added is within a range not exceeding the human working time CT. Generate a robot program based on

On the other hand, as shown in FIG. 10, when the robot working time MCT exceeds the human working time CT by adding the maximum correction time ΔM, the robot program generation unit 15 instructs the process planning unit 12 to We will notify you to that effect. In this case, the process plan formulating unit 12 formulates the process plan again so that the robot work time MCT does not exceed the human work time CT.

As can be seen from the description so far, in the present embodiment, the maximum correction number calculation unit 13 uses the first acquisition unit that acquires information from the design information DB 22, the second acquisition unit that acquires information from the equipment information DB 23, and the acquisition A function as a calculation unit that calculates the maximum number of corrections based on the information obtained is realized. Further, the correction time calculation unit 14 realizes functions as an estimation unit for estimating the maximum correction time based on the maximum number of corrections and as an estimation unit for estimating the work time based on the estimated maximum correction time.

As described above in detail, according to the present embodiment, the maximum number of corrections calculation unit 13 obtains the tolerance information (σa) of the part to be attached and the tolerance information (σbh) of the part to be attached from the design information DB 22. At the same time, the repeat position accuracy Δe of the robot is acquired from the equipment information DB 23 . Based on the acquired information, the maximum number of correction calculation unit 13 calculates the maximum number of times of feedback control (maximum number of corrections Nmax) to be executed during assembly. Further, the correction time calculator 14 calculates the maximum time (maximum correction time) ΔM required for feedback control based on the calculated maximum number of corrections Nmax. As a result, in the present embodiment, the maximum number of corrections Nmax can be estimated from the information on the tolerances of the parts to be assembled and the parts to be assembled, and the accuracy of the robot, and the maximum correction time ΔM can be estimated from the maximum number of corrections Nmax. It is possible to calculate the required time simply and accurately. Therefore, in the present embodiment, it is possible to formulate an appropriate process plan in consideration of the time required for feedback control by formulating a process plan using the time required for assembly work that is calculated with high accuracy.

Further, in the present embodiment, the correction time calculation unit 14 calculates the time required for the robot to move by the minimum guaranteed movement amount Δr obtained from the movement speed (vr) of the robot, the sensing time (Ts), the determination time (Tj ) and the maximum correction time Nmax is the maximum correction time ΔM. This makes it possible to calculate the maximum correction time ΔM of the robot by simple calculation.

In the above-described embodiment, the maximum number of times of correction calculator 13 or the correction time calculator 14 may not perform feedback control in all operations for which feedback control is possible. For example, if the work success rate of the entire robot process satisfies a predetermined standard, feedback control may not be executed. On the other hand, when the work success rate of the entire robot process is below a predetermined standard, feedback control is performed within a range in which the work time MCT of the robot process does not exceed the work time CT of the human process. The work success rate may exceed a predetermined criterion. Which operation is to be feedback-controlled can be determined in consideration of the work success contribution rate of each feedback control and the maximum correction time of each feedback control. The work success contribution rate is a value indicating how much the work success rate is improved when feedback control is executed.

Note that the processing functions described above can be realized by a computer. In that case, a program is provided that describes the processing contents of the functions that the processing device should have. By executing the program on a computer, the above processing functions are realized on the computer. A program describing the processing content can be recorded in a computer-readable recording medium (excluding carrier waves).

When a program is distributed, it is sold in the form of a portable recording medium such as a DVD (Digital Versatile Disc) or a CD-ROM (Compact Disc Read Only Memory) on which the program is recorded. It is also possible to store the program in the storage device of the server computer and transfer the program from the server computer to another computer via the network.

A computer that executes a program stores, for example, a program recorded on a portable recording medium or a program transferred from a server computer in its own storage device. The computer then reads the program from its own storage device and executes processing according to the program. The computer can also read the program directly from the portable recording medium and execute processing according to the program. In addition, the computer can also execute processing in accordance with the received program each time the program is transferred from the server computer.

The embodiments described above are examples of preferred implementations of the present invention. However, the present invention is not limited to this, and various modifications can be made without departing from the spirit of the present invention.

In addition, the following additional remarks will be disclosed with respect to the above description of the embodiment.
(Appendix 1) A first acquiring unit that acquires tolerance information of a first part and tolerance information of a second part to which the first part is assembled from a first storage unit that stores tolerance information of the parts. ,
a second acquisition unit that acquires the minimum distance of the robot that assembles the first part to the second part from a second storage that stores the minimum distance that the robot can move without error;
a calculation unit that calculates a maximum number of times of feedback control that needs to be performed during assembly based on the obtained tolerance information and the minimum distance;
and an estimating unit that estimates the time required for the feedback control based on the calculated maximum number of times of the feedback control.
(Appendix 2) The estimating unit calculates the time required for the robot to move once in the feedback control based on the moving speed of the robot to be assembled and the acquired minimum distance, and executes the feedback control during the calculated time. The time required for the feedback control is defined as the product of the sum of the time required for sensing and the time for determining based on the result of the sensing, and the maximum value of the number of times the feedback control is performed. The information processing apparatus according to appendix 1.
(Supplementary Note 3) The information processing apparatus according to Supplementary note 1 or 2, further comprising an estimating unit that estimates the time required for the assembly work based on the time required for the feedback control estimated by the estimating unit.
(Supplementary note 4) The information processing apparatus according to Supplementary note 3, further comprising a formulation unit that formulates a work plan for allocating the work to the robot, using the time required for the assembly work estimated by the estimation unit.
(Appendix 5) Acquiring tolerance information of a first part and tolerance information of a second part to which the first part is to be assembled from a first storage unit that stores tolerance information of parts;
acquiring the minimum distance of the robot that assembles the first part to the second part from a second storage unit that stores the minimum distance that the robot can move without error;
calculating the maximum number of times of feedback control that needs to be executed during the assembly based on the acquired tolerance information and the minimum distance;
estimating the time required for the feedback control based on the calculated maximum number of times of the feedback control;
A time estimation method characterized in that the processing is executed by a computer.
(Appendix 6) In the estimating process, the time required for the robot to move once in the feedback control is calculated based on the moving speed of the robot to be assembled and the acquired minimum distance, and the time is The time required for the feedback control is defined as the product of the sum of the time required for the sensing to be performed and the time for making a determination based on the results of the sensing, and the maximum value of the number of times the feedback control is performed. The time estimation method according to appendix 5.
(Supplementary note 7) The time estimation method according to Supplementary note 5 or 6, wherein the computer further executes a process of estimating the time required for the assembly work based on the estimated time required for the feedback control.
(Supplementary note 8) The time estimation method according to Supplementary note 7, wherein the computer further executes a process of formulating a work plan for allocating the work to the robot using the estimated time required for the assembling work.
(Appendix 9) Acquiring tolerance information of a first part and tolerance information of a second part to which the first part is to be assembled from a first storage unit that stores tolerance information of parts;
acquiring the minimum distance of the robot that assembles the first part to the second part from a second storage unit that stores the minimum distance that the robot can move without error;
calculating the maximum number of times of feedback control that needs to be executed during the assembly based on the acquired tolerance information and the minimum distance;
estimating the time required for the feedback control based on the calculated maximum number of times of the feedback control;
A time estimation program for making a computer perform processing.

10 information processing device 12 process plan formulation department (formulation department)
13 Maximum number of correction calculation unit (first acquisition unit, second acquisition unit, calculation unit)
14 correction time calculation unit (estimation unit, estimation unit)
22 Design information DB (first storage unit)
23 equipment information DB (second storage unit)

Claims (6)

a first acquisition unit that acquires tolerance information of a first part and tolerance information of a second part to which the first part is to be assembled from a first storage unit that stores tolerance information of the parts;
a second acquisition unit that acquires the repeat position accuracy of a robot that assembles the first part to the second part from a second storage unit that stores the repeat position accuracy of the robot;
a calculation unit that calculates the maximum number of times of feedback control that needs to be performed during assembly based on the acquired tolerance information and the repeat position accuracy;
an estimating unit that estimates the time required when the feedback control is performed the number of times of the maximum value, based on the calculated maximum value of the number of times of the feedback control. The estimating unit calculates the time required for the robot to move once in the feedback control based on the moving speed of the robot to be assembled and the acquired repeat position accuracy, and calculates the time required for the robot to move once in the feedback control. The product of the total time required and the time to determine based on the sensing result, and the maximum value of the number of times of the feedback control, is the time required when the feedback control is performed the number of times of the maximum value. 2. The information processing apparatus according to claim 1, characterized in that it is time. 3. The information processing apparatus according to claim 1, further comprising an estimating unit that estimates the time required for the assembling work based on the time required when the feedback control is performed the number of times of the maximum value estimated by the estimating unit. . 4. The information processing apparatus according to claim 3, further comprising a formulating unit that formulates a work plan for allocating the work to the robot, using the time required for the assembling work estimated by the estimating unit. Acquiring tolerance information of a first part and tolerance information of a second part to which the first part is to be assembled from a first storage unit that stores tolerance information of the parts;
acquiring the repeat position accuracy of a robot that assembles the first part to the second part from a second storage unit that stores the repeat position accuracy of the robot;
calculating the maximum number of times of feedback control that needs to be performed during assembly based on the acquired tolerance information and the repeat position accuracy;
Based on the calculated maximum number of times of the feedback control, estimating the time required when the feedback control is performed the number of times of the maximum value;
A time estimation method characterized in that the processing is executed by a computer. Acquiring tolerance information of a first part and tolerance information of a second part to which the first part is to be assembled from a first storage unit that stores tolerance information of the parts;
acquiring the repeat position accuracy of a robot that assembles the first part to the second part from a second storage unit that stores the repeat position accuracy of the robot;
calculating the maximum number of times of feedback control that needs to be performed during assembly based on the acquired tolerance information and the repeat position accuracy;
Based on the calculated maximum number of times of the feedback control, estimating the time required when the feedback control is performed the number of times of the maximum value;
A time estimation program for making a computer perform processing.

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