Robot motion designing device

Abstract

This robot motion designing device comprises: a shape generation unit (132) that generates, on the basis of requirements pertaining to the shape of a product for which there is operational record regarding a tool having performed a motion thereon, the shape of the product and the shape of the tool that is to perform the motion on the product; a motion-generation information generation unit (133) which generates, on the basis of the generated shapes of the product and the tool, motion-generation information for causing a robot to which the tool is attached to perform a motion on the product; and a robot motion generation unit (134) that generates the motion of the robot on the basis of the motion-generation information.

Description

Robot motion design device CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application is based on Patent Application No. 2024-102364 filed in Japan on June 25, 2024, and the contents of the original application are incorporated by reference in their entirety.

[0002] The present invention relates to a robot motion design device that designs the motion of a robot.

[0003] Patent Document 1 discloses an apparatus for automatically designing a part model of a product that can be assembled by an automated machine without interfering with the product. The apparatus disclosed in Patent Document 1 simulates assembly operations by the automated machine and determines interference between the product and the parts to be assembled, the tool, and the automated machine operating parts during the assembly operation. If interference is determined to occur, a design improvement plan is created to expand the gripping surface of the parts to be assembled that is gripped by the tool. The contents of the prior art documents are incorporated by reference as explanations of the technical elements in this specification.

[0004] JP 2018-41132 A

[0005] As a result of detailed investigation by the inventors, it was found that even when the device disclosed in Patent Document 1 is used, the robot often does not operate as designed due to the influence of product shape tolerances due to product manufacturing, product shape errors, tool operation errors, etc.

[0006] The present disclosure has been made based on this situation, and its purpose is to provide a robot motion design device that can prevent a robot from not operating as designed.

[0007] The above object is achieved by the combination of features recited in the independent claims, and the subclaims define further advantageous specific examples. The reference numerals in parentheses in the claims correspond to specific aspects described in the following embodiments as one aspect, and do not limit the technical scope of the disclosure.

[0008] One disclosure for achieving the above object is a robot motion design device that includes: a shape generation unit that generates a shape of a product and a shape of a tool that will operate on the product based on the requirements of the shape of a product on which the tool has been operated in operation; a motion generation information generation unit that generates motion generation information, which is information for operating a robot to which the tool is attached, on the product based on the generated product shape and tool shape; and a robot motion generation unit that generates the motion of the robot based on the motion generation information.

[0009] The shape generation unit determines the shape of the product and the shape of the tool based on the requirements for the shape of the product that has been used in operation. Actual products have shape errors, and actual tools have operational errors. The shape requirements for the product that has been used in operation with the tool can be said to be the requirements when the tool can operate on the product even if there are shape errors in the product and operational errors in the tool. Therefore, by generating the shape of the product and the shape of the tool based on these requirements, it is possible to reduce the number of cases where the product does not operate as designed in the field.

[0010] A diagram showing the configuration of a robot motion design device according to an embodiment. A diagram conceptually showing a standard tool database. A diagram explaining a tool operation requirement database. A diagram showing the flow of a robot motion design method. A diagram showing detailed processing of S10 in FIG. 4. A diagram showing detailed processing of S20 in FIG. 4. A diagram showing the procedure for checking operation on an actual machine.

[0011] <Embodiments> An embodiment will be described below with reference to the drawings. Fig. 1 is a diagram showing the configuration of a robot motion design device 100 according to this embodiment. The robot motion design device 100 includes an input unit 110, a design support information storage unit 120, and a processing unit 130.

[0012] The input unit 110 is a part that is operated by a user operating the robot motion design device 100 to input various pieces of information to the processing device 130. The input unit 110 is, for example, a keyboard, a mouse, or the like.

[0013] The design support information storage unit 120 stores various information that the processing device 130 refers to when designing the robot's operation. The design support information storage unit 120 stores a standard tool database 121 and a tool operation requirement database 122. It also stores robot operation generation information 123 and actual production operation information 124.

[0014] The standard tool database 121 is a database that stores the correspondence between a plurality of tools and the product handling operations that each tool can perform. A tool is attached to the tip of a robot, such as the tip of a robot arm, and performs a predetermined operation on a product. A product is also sometimes called a workpiece.

[0015] Fig. 2 conceptually illustrates the standard tool database 121. In Fig. 2, seven types of standard tools are included: an internal diameter chuck, a one-point suction tool, a plate-type suction tool, a first friction tool, a second friction tool, a clamping tool, and a coating tool. The standard tool database 121 also specifies the product handling operations that can be performed by each tool.

[0016] The five types of tools, i.e., inner diameter chuck, one-point suction tool, plate-type suction tool, first friction tool, and second friction tool, can perform the gripping operation. The inner diameter chuck grips the product by inserting it into a hole in the product. The one-point suction tool grips the product by adsorbing it to one point. The plate-type suction tool grips the product by adsorbing it to multiple points on the same plane. The first friction tool and second friction tool both clamp the product with multiple clamping parts and grip the product by friction with the product while clamping. The first friction tool and second friction tool have the same gripping means but different shapes. The clamping tool can perform the clamping operation. The application tool can perform the application operation.

[0017] The standard tool database 121 is created based on actual on-site operation records. The executable product handling actions stored in the standard tool database 121 are actions that have been performed on-site using standard tools. Since the standard tools have been used on-site, it can also be said that the actions have been performed using standard equipment.

[0018] The tool operational requirement database 122 is a database that stores requirements necessary for the operation of each tool stored in the standard tool database 121. The tool operational requirement database 122 is also created based on actual operation records in the field. The tool operational requirement database 122 is created for each standard tool. The tool operational requirement database 122 will be described with reference to FIG. 3.

[0019] 3 shows the tool operation requirement database 122 for the first friction tool. Items and requirements for each item are stored in the tool operation requirement database 122. The items shown in FIG. 3 include the shape of the tool body, the shape of the tool periphery, the tool operation relative to the product, the shape of the product, and the gripping position.

[0020] The tool body shape includes the gripping portion shape and the friction material shape as requirements. The friction material shape is an example of a part where the tool exerts its working effect. The gripping portion shape refers to the shape of the gripping portion of the tool body, and the actual database specifically records this shape. The friction material shape refers to the shape of the friction material provided in the first friction tool for gripping, and the actual database specifically records this shape.

[0021] The tool peripheral shape is the shape of the part of the robot body to which the tool is attached. The requirements for the tool body shape and the requirements for the tool peripheral shape are requirements for the shape of the tool.

[0022] The tool operation relative to the product refers to the tool operation when the tool operates relative to the product. More specifically, it refers to the tool operation after the robot with the tool attached is positioned at the work start point where the robot begins its operation relative to the product, and the tool operation after the robot is positioned at the work end point where the robot ends its operation relative to the product. Figure 3 shows the operation direction and amount as requirements for this item. For example, to explain a specific example of these requirements using the gripping of a product as an example of the operation, the operation after arriving at the work start point is to move z (cm) in a direction of a predetermined angle (°), such as directly downward, and then perform a clamping operation. The operation after arriving at the work end point is to perform a release operation, which is the opposite of the clamping operation, and then return to the position where the operation started from the work start point.

[0023] The tool operation requirement database 122 may include a subtraction model calculated based on the tool operation relative to the product and the tool body shape. The subtraction model represents a three-dimensional trajectory when the tool body shape performs an operation defined in the tool operation requirement relative to the product. Therefore, the subtraction model is a three-dimensional model.

[0024] The tool operation requirement database 122 also includes an item for the shape of the product. This is because the tool alone does not determine whether the tool can perform an operation on the product. The tool operation requirement database 122 can also be called a database of product shapes. Furthermore, the product shape alone does not determine whether the tool can perform an operation on the product. Therefore, it is preferable to determine the product shape and the tool shape at the same time.

[0025] FIG. 3 shows the requirements for the shape of the product, including the shape of the gripped part, the area in contact with the tool, and the method for creating the gripped part. The requirements for the shape of the gripped part specify the specific shape and size that the gripped part must have. The requirements for the shape of the gripped part also include the tolerances for the shape and dimensions of the gripped part. The requirements for the shape of the gripped part may also specify the shape and minimum size. The shape and minimum size of the gripped part may be shown using a 3D model. This 3D model may also be called an additive model.

[0026] The requirement for the area in contact with the tool defines the specific range of the area that comes into contact with the tool. The requirement for the method of creating the gripped part defines how the gripped part must be created, for example, by press processing or bonding. The requirement for the gripping position defines which position on the product is to be gripped. For example, as shown in Figure 3, it may be a millimeter above the bent part.

[0027] Returning to FIG. 1 for the explanation, the robot motion generation information 123 stored in the design support information storage unit 120 is information necessary for generating robot motion and can be stored in advance. An example of this information is a coordinate transformation formula for generating robot motion. This transformation formula is a formula for calculating the motion of the robot in which the tip of the robot moves from the work start point to the work end point input by the user when the user inputs the coordinates of the work start point and the work end point of the robot motion. The robot motion generation information 123 also includes information for calculating the time it takes for the tip of the robot to move from the work start point to the work end point. This information may be the coordinate transformation formula for generating robot motion described above, or may be one or more other calculation formulas.

[0028] The actual production operation information 124 stored in the design support information storage unit 120 is information indicating the operating conditions of the robot during actual production. This information includes the work start point, work end point, and detailed information on the tools used for the robot operation.

[0029] The processing device 130 includes at least one of a processor and a circuit as a hardware configuration. For example, the processing device 130 can be realized by a computer including a processor and a memory. Alternatively, the processing device 130 may not include a processor and may include hardware circuits other than the processor, or may include a processor and hardware circuits other than the processor. The processing device 130 includes a tool selection unit 131, a shape generation unit 132, a motion generation information generation unit 133, and a robot motion generation unit 134 as functions realized by the above hardware configuration.

[0030] The tool selection unit 131 selects a tool that will perform the product's operation. The shape generation unit 132 determines the product's shape that can execute the operation with the selected tool. The movement generation information generation unit 133 generates information necessary for the robot movement generation unit 134 to generate the overall movement of the robot. The robot movement generation unit 134 generates the overall movement of the robot. The operations performed by each of these units will be described in detail using Figure 4 and subsequent figures.

[0031] Figure 4 shows the flow of the robot motion design method implemented using the robot motion design device 100. In step (hereinafter, "step" is omitted) S10, a tool to be used is selected. Details of this process are shown in Figure 5. In Figure 5, in S11, a rough design of the product size and shape is converted into data. The process of S11 is performed based on user input using the input unit 110. The user inputs information from the input unit 110 that allows the rough size and shape of the product to be determined.

[0032] In S12, the standard tool database 121 is referenced. In S13, it is determined based on the reference result in S12 whether the product can be operated with the standard tool. This determination can be made by the user by referring to the standard tool database 121. Alternatively, the processing device 130 may make this determination by having the user input the operation that the tool is to perform this time.

[0033] If the determination result in S13 is NO, the process proceeds to S14. In S14, it is determined whether the product design can be changed. This determination is made by the user. If the product design can be changed, the process returns to S11, and the rough design of the product is changed based on the user's input operation. On the other hand, if the product design cannot be changed, the process proceeds to S15. In S15, it is determined that design will be performed using a new tool.

[0034] If the determination result in S13 is YES, the process proceeds to S16. In S16, the standard tool determined to be compatible in S13 is determined as the tool to be used for the current design. By determining the tool, the tool type and the tool shape are also determined. However, the tool shape may be modified during product design in S20.

[0035] 5, steps S11 and S16 are executed by the tool selection unit 131. Steps S12 and S13 can also be executed by the tool selection unit 131. Steps S12 and S13 may be executed by the user. Steps S14 and S15 are executed by the user.

[0036] Returning to FIG. 4 for the explanation, in S20 of FIG. 4, detailed design of the product is performed using the tool selected in S10. Details of the processing of S20 are shown in FIG. 6. In S21, it is determined whether interference will occur when the tool selected in S16 is operated on the product digitized in S11. This determination is made by referring to the tool operation requirement database 122. For example, the item "Tool Operation on Product" is referenced. If the shape of the product is such that, after the tool is positioned at the operation start point, the tool is moved in the operation direction required by the "Tool Operation on Product" requirement, and another part of the product interferes with the tool as it moves to the gripped portion of the product, the determination result in S21 is YES. Note that the operation start here is a position relative to the product. This operation start point may be included in the tool operation requirement database 122. The determination in S21 may be made by a user by referring to the tool operation requirement database 122, or may be made automatically by the processing device 130 by referring to the tool operation requirement database 122.

[0037] If the determination result in S21 is YES, the process proceeds to S22. In S22, a subtraction model is read from the tool operation requirement database 122. In the following S23, it is determined whether the product will interfere with the subtraction model when the subtraction model read in S22 and the product are placed based on the work start point of the tool. If the determination result in S23 is NO, the process proceeds to S25 without executing S24.

[0038] If the determination result in S23 is YES, S24 is executed. In S24, the product shape is cut out by the subtraction model. In other words, the part of the product shape that interferes with the subtraction model is deleted. If there is interference with the subtraction model, the tool and the product will interfere when the tool operates on the product. If the tool operation requirement database 122 includes a subtraction model, it is a requirement of the product shape that the product shape does not interfere with the subtraction model.

[0039] S25 and S26 are executed when the action performed by the tool is grasping. If the action performed by the tool is not grasping, S25 and S26 are omitted and S27 is executed. In S25, an additive model is read from the tool operation requirement database 122. In S26, shape modification is performed to fit the additive model. The additive model is a 3D representation of the shape and minimum size of the grasped part. Therefore, if the grasped part of the product was too small before S26 was executed, the grasped part is modified in S26 to be larger to the size of the additive model.

[0040] By executing the processes from S22 to S26, a subtractive model and an additive model can be used to create a product shape that does not interfere with a tool and can be gripped by the tool. However, a product shape that does not interfere with a tool may also be designed without using a subtractive model. For example, a user may refer to the tool operation requirement database 122 and modify the product shape to a shape that does not interfere with the tool through user operation. Alternatively, a user may refer to the tool operation requirement database 122 and modify the shape of a gripped part to a shape that can be gripped by the tool through user operation.

[0041] In S27, the product shape is modified to conform to other requirements shown in the tool operation requirement database 122. For example, if the tool grips the product to satisfy the requirement for "area in contact with the tool," which is a requirement in the "product shape" item, an area large enough to contact the bent portion is required. In this case, the requirement for "gripping position," "a millimeter above the bent portion," cannot be satisfied. Therefore, the shape of the gripped portion is modified to be larger.

[0042] Although the above has been a description of modifying the shape of the product, the requirements for the product may be satisfied by modifying the tool within the scope of satisfying the requirements for the tool.

[0043] In S28, it is confirmed whether the requirements of the product specifications are satisfied. It is confirmed whether the product shape has been modified in S22 to S27, resulting in a shape that does not satisfy the requirements of the product specifications. If the result of the confirmation is that the shape does not satisfy the requirements of the product specifications, the product shape is modified again. If the result of the confirmation is that the requirements of the product specifications are satisfied, the process proceeds to S29. Furthermore, if the determination result in S21 is NO, the process also proceeds to S29. The processes of S27 to S28 can be performed by the user while operating the processing device 130. Alternatively, the processing device 130 may automatically perform the processes by referring to the tool operation requirement database 122.

[0044] In S29, the product shape at the time of execution of S29 is determined as the product shape to be used in subsequent processing. Also, the tool shape at the time of execution of S29 is determined as the tool shape to be used in subsequent processing. Of the processing shown in FIG. 6, the processing performed by the processing device 130 corresponds to the function of the shape generation unit 132.

[0045] Returning to FIG. 4 for the explanation, steps S30 and S40 are executed by the motion generation information generating unit 133. Motion generation information is generated in S30. The motion generation information is information necessary for generating robot motion and can be determined by the processing in FIG. 4. The motion generation information includes the work start point, the work end point, the tool motion relative to the product, and the product coordinates. The work start point, the work end point, and the product coordinates are acquired based on a user's input operation. The work start point, the work end point, and the product coordinates may be stored in the design support information storage unit 120 before S30 is executed, and may be acquired from the design support information storage unit 120 in S30. The tool motion relative to the product is stored in the tool motion requirement database 122 for the tool selected in S10. In addition, the motion generation information may include other information, such as the type and shape of the tool, the position for recognizing the product position, and information indicating the required time for the tool motion. The position for recognizing the product position is also called the vision recognition position.

[0046] In S40, the motion generation information generated in S30 and the data indicating the product shape determined in S20 are passed to the robot motion generation unit 134.

[0047] S50 is executed by the robot motion generation unit 134. In S50, the overall motion of the robot is generated. Specifically, first, the task start point and task end point obtained from the motion generation information generation unit 133 are substituted into the coordinate transformation formula for robot motion generation included in the robot motion generation information 123. This calculates the robot motion for moving the tip of the robot from the task start point to the task end point input by the user. In addition, the time required for the tip of the robot to move from the task start point to the task end point is calculated based on the information included in the robot motion generation information 123.

[0048] Next, the tool motions at the work start point and work end point are added. The tool motions at the work start point and work end point are tool motions on the product acquired from the motion generation information generating unit 133.

[0049] In S60, the reference position within the workpiece is registered. This position is the reference position set for the workpiece, i.e., the product. The reference position is the position that serves as the reference when correcting the position. Registration is performed by user operation. When the robot operates, the product is recognized by a recognition device such as a camera, and the recognized position is compared with the registered reference position to correct the position. By performing the processing up to this point, information is prepared in the virtual space to allow the robot to operate on the product.

[0050] In S70, the robot is operated in virtual space, and the machine time, i.e., the time required for the entire operation, is measured. In S80, it is determined whether there was any interference during the operation in S70. If the determination result in S80 is NO, the process returns to S20, and one or both of the product shape and the tool shape are changed. Note that it is also possible to return to S10 instead of S20 and select a different tool.

[0051] If the determination result in S80 is YES, the process proceeds to S90. In S90, it is determined whether the machine time measured in S70 is within a specified value. If the determination result in S90 is NO, the process also returns to S20, where one or both of the product shape and the tool shape are changed. Also, if the determination result in S90 is NO, the process may return to S10 instead of S20, and a different tool may be selected. If the determination result in S90 is YES, the process of FIG. 4 ends.

[0052] When the processing in FIG. 4 is completed, an operation check is performed on the actual machine. The procedure for checking operation on the actual machine is shown in FIG. 7. In S101, the jig and product are placed in predetermined positions. In S102, the actual robot is operated to check operation, such as checking for interference and machine time. If this operation check is OK, it means that there is no problem in carrying out actual production using the robot operation details in S102. Therefore, the process proceeds to S103, and actual production operation information 124 indicating the operation details of the robot in S102 is stored in the design support information storage unit 120. Thereafter, actual production is carried out using the actual machine using this stored actual production operation information 124.

[0053] According to the embodiment described above, the shape generation unit 132 determines the shape of a product based on the shape requirements of a product that has a history of operation. The shape generation unit 132 also determines the shape of a tool based on the shape requirements of a product that has a history of operation. The shape requirements of a product that has a history of operation in which a tool has been operated can be said to be requirements that apply when the tool can operate on a product even if there are shape errors in the product and operational errors in the tool. Therefore, by generating the shape of a product and the shape of a tool based on these requirements, it is possible to reduce the number of cases in which the product does not operate as designed in the field.

[0054] Furthermore, in addition to requirements for the shape of the product, requirements for the shape of tools with a proven track record of operation are also included in the tool operation requirement database 122. By taking into consideration requirements for the shape of tools with a proven track record of operation in addition to requirements for the shape of products with a proven track record of operation, it is possible to further reduce the number of situations in which a product does not operate as designed in the field.

[0055] The tool operation requirement database 122 also includes tool operations relative to the product. The tool operations relative to the product are the operation of the tool relative to the product from the work start point and the operation of the tool relative to the product at the work end point. The robot operation generation unit 134 generates robot operations in which the tip of the robot moves from the work start point to the work end point based on the coordinates of the work start point and the work end point input by the user. Then, the tool operations relative to the product included in the tool operation requirement database 122 are added to the generated operations to generate robot operations in virtual space. In this way, operations that have been proven in the field can be simulated in virtual space.

[0056] A subtraction model can be included in the tool operation requirement database 122. The subtraction model is a model that indicates a three-dimensional trajectory that represents in three dimensions the trajectory of the "operation of the tool on the product" that has a proven track record, that is, the trajectory when the operation on the product is performed from the work start point, and the trajectory when the operation on the product is performed at the work end point.

[0057] The robot operation generation unit 134 generates a product shape that does not interfere with this subtraction model (S23, S24). In this way, it is possible to reduce the occurrence of interference between the product and the tool on-site.

[0058] An additive model can be included in the tool operation requirement database 122. The additive model is a requirement for the shape and minimum size of a gripped portion of a product, for a tool that performs a gripping operation, to enable the tool to grip the product.

[0059] The robot motion generator 134 adapts the shape of the gripped part of the product to this additive model (S26). By doing so, it is possible to reduce the number of cases where the tool is unable to grip the product on-site.

[0060] Although the embodiments have been described above, the disclosed technology is not limited to the above-described embodiments, and the following modifications are also included in the scope of the disclosure. Furthermore, various modifications other than those described below can be made without departing from the spirit of the invention.

[0061] <Modifications> For example, in the embodiment, the tool operation requirement database 122 is provided, and the tool operation requirement database 122 includes requirements related to tools and requirements related to the shapes of the surrounding areas of the tools. However, these may not be included in the tool operation requirement database 122, and the shape of the product may be determined using only requirements related to the product. This is because, when the tool selection unit 131 selects a tool with a proven track record, the shape of the product has the greatest influence on whether or not the tool will operate on-site. In this case, the shape of the tool selected by the tool selection unit 131 is used as the shape of the tool generated by the shape generation unit 132.

Claims

1. A robot motion design device comprising: a shape generation unit (132) that generates a shape of a product and a shape of a tool that will operate on the product based on the requirements of the shape of the product on which the tool has been operated in operation; a motion generation information generation unit (133) that generates motion generation information, which is information for operating a robot to which the tool is attached on the product, based on the generated shape of the product and shape of the tool; and a robot motion generation unit (134) that generates the motion of the robot based on the motion generation information.

2. A robot motion design device as described in claim 1, wherein the shape generation unit generates the shape of the product and the shape of the tool based on the requirements of the shape of the product that has a history of operation, as well as the requirements of the shape of the tool that has a history of operation.

3. A robot motion design device as described in claim 1, comprising a database (122) storing the motion of the tool that has a proven track record, the motion of the tool relative to the product from the work start point and the motion of the tool relative to the product at the work end point, wherein the robot motion generation unit substitutes the coordinates of the work start point and work end point input by the user into a coordinate transformation formula for generating robot motion, generates the motion of the robot in which the tip of the robot moves from the work start point to the work end point, and adds the motion of the tool stored in the database to the generated motion, thereby generating robot motion in virtual space.

4. A robot motion design device as described in claim 1, which is provided with a database (122) that stores three-dimensional trajectories that represent in three dimensions the trajectory of the operation of the tool that has a proven track record when the operation is performed on the product from the start point of the work and the trajectory of the operation on the product at the end point of the work, and the requirements for the shape of the product include a requirement that it does not interfere with the three-dimensional trajectory, and the shape generation unit generates a shape of the product that does not interfere with the three-dimensional trajectory.

5. A robot motion design device as described in claim 4, wherein the database stores requirements for the shape and minimum size of the graspable portion of the product to enable the tool performing the grasping operation to grasp the product, and the shape generation unit generates the shape of the product so as to satisfy the requirements for the shape and minimum size of the graspable portion.

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