Motion path generating device and motion path generating method

Abstract

To provide a motion path generating device that can reduce a time period required to generate appropriate motion paths for a plurality of robots.SOLUTION: A processor 13 includes: a teaching motion registering unit 131 in which teaching motions of robot are registered; and a constraint condition registering unit 132 in which constraint conditions including order constraints for robot motions are registered. A motion path generating device 1 includes: an initial path generating unit 133 that generates motion paths for a plurality of robots; and a correcting unit 134 that corrects motion start times of respective parts. The initial path generating unit 133 determines motion start times of respective parts on the basis of teaching motions and the constraint conditions, and generates interference avoidance paths for the plurality of robots between two teaching motions. The correcting unit 134 corrects the motion start times of the robots on the basis of the generated motion path.SELECTED DRAWING: Figure 3

Description

Technical Field

[0001] The disclosure in this specification relates to an operation path generation device and an operation path generation method.

Background Art

[0002] Patent Document 1 discloses a method of teaching operations so that when a plurality of robots perform operations simultaneously within a common work area, the robots do not interfere with each other while avoiding obstacles. In this method, when the passing areas of the respective robots intersect, a constraint condition that none of the robots can pass is additionally set. Further, under that constraint condition, teaching values for each robot to move while avoiding obstacles based on an operation command are generated again.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In Patent Document 1, in order to generate an operation path for avoiding an obstacle based on the above constraint condition, since the operation path becomes redundant, the time for determining the operation path can be lengthened. The method disclosed in Patent Document 1 has room for improvement with respect to determining an operation path in a short time. One of the objects disclosed in this specification is to provide an operation path generation device and an operation path generation method that can shorten the time for determining an operation path for a plurality of robots.

Means for Solving the Problems

[0005] The multiple aspects disclosed in this specification adopt different technical means to achieve their respective purposes. Also, the claims and the reference numerals in parentheses described in this section are an example showing the correspondence relationship with the specific means described in the embodiments to be described later as one aspect, and do not limit the technical scope.

[0006] One of the disclosed operation path generation devices is an operation path generation device (1) that generates operation paths for a plurality of robots (21, 22), a teaching operation registration unit (131) in which teaching operations for the robots are registered, a constraint condition registration unit (132) in which constraint conditions including at least order constraints for the operations of the robots are registered, an initial path generation unit (133) that determines the operation start times of the robots based on the teaching operations and the constraint conditions, generates interference avoidance paths for the plurality of robots between two teaching operations, and generates operation paths for the plurality of robots, a correction unit (134) that corrects the operation start times of the robots based on the generated operation paths, and includes.

[0007] One of the disclosed operation path generation methods is an operation path generation method for generating operation paths for a plurality of robots (21, 22), determining the operation start times of the robots based on the registered teaching operations of the robots and the constraint conditions registered including at least order constraints for the operations of the robots, generating interference avoidance paths for the plurality of robots between two teaching operations, and generating operation paths for the plurality of robots (S120), correcting the operation start times of the robots based on the generated operation paths (S130), and includes.

[0008] Accordingly, the operation start time of the robot determined based on the teaching operation and the constraint conditions is corrected based on the initially generated operation path. This makes it possible to omit the search for unnecessary operation paths, and for example, the overall operation time related to a plurality of robots can be corrected to be improved. This device and method can generate the operation path by separating the initial generation of the operation path and the optimization of the operation start time. Therefore, it contributes to reducing the waiting time of each robot and reducing the time for generating an appropriate operation path.

Brief Description of the Drawings

[0009]

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Modes for Carrying Out the Invention

[0010] Hereinafter, a plurality of modes for carrying out the present disclosure will be described with reference to the drawings. In each mode, parts corresponding to those described in the preceding mode may be given the same reference numerals and redundant descriptions may be omitted. When only a part of the configuration is described in each mode, other modes described previously can be applied to other parts of the configuration. Not only combinations of parts that are clearly shown to be combinable in each embodiment, but also embodiments can be partially combined with each other as long as there is no problem with the combination, even if not explicitly stated.

[0011] <First Embodiment> The first embodiment will be described with reference to FIGS. 1 to 6. FIG. 1 is a configuration diagram of the operation path generation apparatus 1 according to the first embodiment. The operation path generation apparatus 1 is an apparatus that generates an operation path for each of a plurality of robots and surrounding obstacles. The obstacles are objects that become obstacles when the first shaft portion, the second shaft portion, and the chuck portion of each robot move. The obstacles include each part of the robot or an object located in the periphery other than the robot.

[0012] Each of the plurality of robots shown in FIG. 2 includes two shafts, two joints, and one chuck. The robot 21 includes a first shaft portion 211 and a second shaft portion 213, a first joint 212 and a second joint 214, and a chuck portion 215. The robot 22 includes a first shaft portion 221 and a second shaft portion 223, a first joint 222 and a second joint 224, and a chuck portion 225. The robots shown in the figure have a simplified configuration for explaining the embodiment. The robot may have a configuration having three or more shafts and joints. Each robot is operable in a three-dimensional space.

[0013] The first joint 212 of the robot 21 is provided at the end of the first shaft portion 211 and enables the first shaft portion 211 to rotate around a rotation axis orthogonal to the first shaft portion 211. The first shaft portion 211 is relatively rotatable with respect to the base by the first joint 212 and is, for example, connected to the base. The base is installed, for example, on the floor or an installation table.

[0014] The second joint 214 of the robot 21 is provided at the end of the first shaft portion 211 on the side without the first joint 212. The second joint 214 connects the end of the first shaft portion 211 and the end of the second shaft portion 213. The second joint 214 enables the second shaft portion 213 to rotate relative to the first shaft portion 211 around a rotation axis orthogonal to the first shaft portion 211 and the second shaft portion 213. The chuck portion 215 is provided at the end of the second shaft portion 213 on the side without the second joint 214. The chuck portion 215 is a pair of gripping portions with one end open and can grip objects such as parts. The chuck portion 215 is rotatably provided around the axis of the second shaft portion 213. In FIG. 2, the shapes of the first shaft portion 211 and the second shaft portion 213 are rod-shaped. However, the shapes of the first shaft portion 211 and the second shaft portion 213 do not have to be rod-shaped and can be variously changed according to the use of the robot.

[0015] The angular range in which the first shaft portion 211 is relatively rotatable with respect to the base and the range in which the second shaft portion 213 is relatively rotatable with respect to the first shaft portion 211 can be variously set by a mechanical mechanism or an electrical mechanism. The configuration regarding the robot 22 is the same as that of the robot 21, and the above-described explanation regarding the robot 21 can be incorporated. The first shaft portion 221 and the first joint 222 correspond to the first shaft portion 211 and the first joint 212. The second shaft portion 223 and the second joint 224 correspond to the second shaft portion 213 and the second joint 214. The chuck portion 225 corresponds to the chuck portion 215.

[0016] The motion path generation device (MPD) 1 includes an input device (IPD) 11, a display device (DPD) 12, a processor (PCS) 13, a ROM 14, and a RAM 15. The motion path generation device 1 having such a configuration can also be realized by a general-purpose computer. The motion path generation device 1 can also be realized by a virtual machine. The motion path generation device 1 can also be realized by a system including a server capable of communicating with a computer and the computer. The motion path generation device 1 can also be realized by a system including a cloud or virtual machine capable of communicating with a computer and the computer.

[0017] The input device 11 has a keyboard, a predetermined button, etc., and can be used to input the structure of the aforementioned robot, the position of obstacles, the motion path start point, the motion path end point, etc. The inputtable robot structure includes the length and width of the first shaft portion and the second shaft portion, the position of the first joint, the relative position of the second joint with respect to the first shaft portion and the second shaft portion, etc. The position of the obstacle specifies the space where the obstacle exists by coordinates. The display device 12 can display the motion path of the robot, the motion schedule, etc. generated by the motion path generation device 1.

[0018] In the ROM 14, which is a non-volatile storage medium, a motion path generation program executed by the processor 13 is stored. By the processor 13 executing the motion path generation program stored in the ROM 14 while utilizing the temporary storage function of the RAM 15, the processor 13 executes each part shown in FIG. 3. The processor 13 executing each part shown in FIG. 3 means that the motion path generation method corresponding to the motion path generation program is executed.

[0019] As shown in FIG. 3, the processor 13 includes an instruction motion registration unit 131, a constraint condition registration unit 132, an initial path generation unit 133, and a correction unit 134. The processing executed by each of these units will be described with reference to the flowchart shown in FIG. 4.

[0020] The flowchart shown in FIG. 4 starts with the start operation of the user of the operation path generation device 1. The user of the operation path generation device 1 includes a person who can visually confirm the robot at a position where the robot can be seen with the naked eye and a person who can operate the robot remotely from a position where the robot can be operated. By executing the flowchart shown in FIG. 4, the time for determining the operation path of the robot can be shortened, and an appropriate operation path can be generated.

[0021] The plurality of robots operate freely in the joint space included in the three-dimensional space. The joint space is a coordinate space defined by the number of dimensions of the joints of each robot. The angle of the first joint can also be considered as the angle of the first shaft portion with respect to the base. The angle of the second joint can also be considered as the angle of the second joint with respect to the first joint. Since the posture of the robot can be expressed by the angles of the joints, the posture of each robot is determined when the coordinates are determined in the joint space.

[0022] Step (hereinafter, the step is omitted) S100 is a process executed by the teaching operation registration unit 131. In S100, the teaching operation taught by the user is registered. For example, the registration of the teaching operation can be performed by the user using the input device 11. The registration of the teaching operation may be configured to be temporarily stored in the RAM 15, for example. The teaching operation is the registration of waypoints that the robot needs to pass through, parameters and waypoint sequences related to operations such as Pick, Place, and screw tightening. The waypoint sequence is a set of registered waypoints.

[0023] The teaching operation includes control contents related to the robot, working positions and postures, etc., given to the operation path generation device 1. Note that the operation path generation method may be configured such that the operation path generation program reads a pre-registered teaching operation and does not perform the registration of the teaching operation by S100. The registration of the teaching operation may include an interpolation method for how the robot operates in the waypoint section. In S100 or before S100, the user may input the structure of the robot, the position of the obstacle, the start point of the operation path, the end point of the operation path, etc. using the input device 11.

[0024] S110 is a process executed by the constraint condition registration unit 132. In S110, constraint conditions including at least the order constraint of operations are registered for each robot. The order constraint is a constraint related to the operation order of each robot or a constraint related to the operation order among a plurality of robots. When the order constraint is registered, the processor 13 determines the operation timing of each robot according to the constraint and controls the operation of the robot. The constraint conditions include cooperation conditions for smoothly connecting the operations between two teaching operations. The cooperation conditions include passing through waypoints or smoothly connecting between teaching operations within a range that does not interfere with obstacles. The constraint conditions include determining which robot's teaching operation takes precedence for a plurality of robots.

[0025] When this constraint condition is not registered, it is not determined which robot takes precedence, and the order is arbitrary. Also, the operation order of the robot to which the constraint condition is not applied is determined so as to improve evaluation values such as the operation time and minimize the operation time.

[0026] For example, the registration of the constraint condition can be performed by the user using the input device 11. The registration of the constraint condition may be configured to be temporarily stored in the RAM 15, for example. Note that the operation path generation method may be configured such that the operation path generation program reads the pre-registered constraint conditions and does not perform the registration of the constraint conditions by S110. In S110 or before S110, the user may input the above-mentioned constraint conditions using the input device 11.

[0027] S120 is a process executed by the initial path generation unit 133. In S120, the order of the teaching operations of each robot is extracted so that the teaching operations satisfy the constraint conditions including the order constraints. In S120, for example, a simulator is used to determine whether the teaching operations can be executed simultaneously, such as when the teaching operations interfere between multiple robots. If the teaching operations cannot be executed simultaneously, an operation order that allows the operations to satisfy the constraint conditions is determined, and the operation start time determined based on this operation order is set as the initial value. The operation start time is the time to start the operation for each robot, in other words, the timing when the movement of the teaching operation starts for each robot.

[0028] Furthermore, in S120, for two teaching operations, a non-interference path where multiple robots do not collide is generated. The non-interference path is, for example, a path that does not collide between a robot and a surrounding object or between robots. The operation path generation device 1 has a map including non-interference paths created in advance based on information such as self-interference of each robot, interference with peripheral equipment, and interference between robots. The processor 13 randomly searches when exploring this map to generate a non-interfering operation path. By mapping the non-interference paths in advance, the processor 13 can quickly obtain the path generation of multiple robots.

[0029] Figure 5 shows an example of the processing of the initial path generation unit and the processing of S120. The example shown in Figure 5 shows the vertical and horizontal movements related to each teaching operation for robot 21 and robot 22. Examples of the teaching operations of the robot are the PICK operation of picking up a part and the PLACE operation of placing a part. The operation steps shown above Figure 5 show the result of determining the order of the teaching operations based on the order constraints and determining the start time of each operation. The operation steps shown in the figure include the adjustment width ensured between teaching operations (also referred to as between teaching operations). The adjustment width is the adjustable time regarding the determined operation start time. Only with teaching operations, the operation time of the robot between teaching operations is not included, so an operation path between teaching operations is generated to calculate the adjustable time. The processor 13 adjusts by changing the operation start time of the teaching operation within the range of this adjustment width.

[0030] The operation steps shown below Figure 5 show the result of generating the interference avoidance operation between teaching operations in order from the start of the teaching operation and updating the operation start time according to the interference avoidance operation. The processor 13 generates an interference avoidance path for a plurality of robots between two teaching operations and generates an operation path for the plurality of robots.

[0031] S130 is the processing executed by the correction unit 134. In S130, with the path added between teaching operations as the initial solution, it is optimized so that the overall operation time is shortened. In S130, an operation optimization process is executed to correct the operations of each robot and optimize as a whole. In S130, the operation start time of the robot is corrected so that the overall operation time related to a plurality of robots becomes smaller. In S130, the operation start time of the robot is corrected so that the evaluation value improves regarding the overall operation related to a plurality of robots. The processor 13 can obtain an operation that satisfies the target evaluation value even if it is not the optimal solution by gradually improving the operations executable by the correction unit 134.

[0032] Processor 13 searches for the operation start time of the teaching operation within a range that satisfies the order constraints. Also, processor 13 searches for the operation start time of operating the non-interference path generated in S120. Also, processor 13 calculates a range of operation start times that may improve the evaluation value while satisfying the order constraints. Processor 13 searches for an operation start time within the calculated range of operation start times that improves the evaluation value. By searching for the operation start time that improves the evaluation value for the overall operation, processor 13 can minimize the overall operation time for multiple robots. Processor 13 searches for the operation start time so that the evaluation value of the entire operation improves. Searching so that the evaluation value improves means, for example, searching for the operation start time so that the operation time of the entire operation becomes shorter. Processor 13 uses, as the evaluation value, further the energy consumption, the amount of movement of each joint, the amount of movement of the end effector such as the chuck part, etc., and evaluates these by weighting. Also, as a search method, processor 13 can use, for example, binary search when the evaluation value changes linearly and Bayesian optimization when the evaluation value is non-linear. As a search order, processor 13 can prioritize a single robot over multiple robots and execute in ascending order of the operation start time. Also, when there are multiple adjustable operation start times, processor 13 can execute in descending order or randomly, or perform parallel search.

[0033] FIG. 6 shows an example of the processing of the correction part and the processing of S130. The example shown in FIG. 6 shows that the operation start time has been corrected with respect to each teaching operation and interference avoidance operation of robot 21 and robot 22 compared to the example shown in FIG. 5. Processor 13 corrects the operation start time of each part little by little instead of optimizing it all at once. Processor 13 determines the operation start time of each part while looking at the state of shortening the overall operation time for multiple robots. In the example shown in FIG. 6, although the operation start timing of each part has been changed, the operation path has not changed with respect to the operation path determined by the initial path generation unit 133.

[0034] The processor 13 controls to smoothly connect the teaching operation and the collision avoidance operation so that each robot can quickly start the next teaching operation. For example, the amount of smooth connection is controlled when the position of the hand at the waypoint is within the specified distance range or when the distance from the obstacle is more than a certain distance. To avoid interference between two robots, when both are waiting, there may be an operation start time that does not cause interference even if one starts operating before the other. In this case, the processor 13 can optimize the operation start time little by little within the range that satisfies the order constraint and does not cause interference.

[0035] In S140, using the operation start time corrected in S130, an operation path is generated for a plurality of robots. As described above, the processor 13 can provide an operation path that can shorten the time for determining the operation path for a plurality of robots.

[0036] The operation and effect brought by the operation path generation device 1 of the first embodiment will be described. The operation path generation device 1 is a device that generates an operation path related to a plurality of robots. The operation path generation device 1 includes a teaching operation registration unit 131 in which a teaching operation related to the robot is registered, and a constraint condition registration unit 132 in which constraint conditions including at least the order constraint of the operation regarding the robot are registered. The operation path generation device 1 includes an initial path generation unit 133 that generates an operation path for a plurality of robots, and a correction unit 134 that corrects the operation start time of the robot. The initial path generation unit 133 determines the operation start time of the robot based on the teaching operation and the constraint conditions, and generates a collision avoidance path for a plurality of robots between two teaching operations. The correction unit 134 corrects the operation start time of the robot based on the generated operation path.

[0037] This device modifies the operation start time determined based on the teaching operation and the constraint conditions according to the initially generated operation path. As a result, it is possible to omit the search for unnecessary operation paths. This device can be modified, for example, to improve the overall operation time of a plurality of robots. According to this device, the operation path can be generated by separating the initial generation of the operation path and the optimization of the operation start time. Therefore, the waiting time of each robot can be reduced, and the time for generating an appropriate operation path can be reduced. Also, it is possible to optimize the operation start time and provide a device that can generate the operation paths of a plurality of robots based on the modified operation start time.

[0038] The operation path generation method includes determining the operation start time of a robot based on the registered teaching operation of the robot and the constraint conditions registered including at least the order constraint of the operations for the robot, generating an interference avoidance path for a plurality of robots between two teaching operations, and generating an operation path for the plurality of robots. Further, this method includes modifying the operation start time of the robot based on the generated operation path.

[0039] This method modifies the operation start time determined based on the teaching operation and the constraint conditions so that the overall operation time of a plurality of robots is improved according to the initially generated operation path. According to this method, the operation path can be generated by separating the initial generation of the operation path and the optimization of the operation start time. By this procedure, the waiting time of each robot can be reduced, and the time for generating an appropriate operation path can be reduced. Also, it is possible to optimize the operation start time and provide an operation path generation method that can generate the operation paths of a plurality of robots based on the modified operation start time.

[0040] <Second Embodiment> The second embodiment will be described with reference to FIGS. 7 and 8. According to FIGS. 7 and 8, the operation path generation device of the second embodiment will be described. For steps, configurations, operations, and effects not specifically described in the second embodiment, they are the same as those in the first embodiment, and only the differences from the first embodiment will be described below.

[0041] The second embodiment is different from the first embodiment in that it includes an adjustment width setting unit 1331 and a processing step of S115. According to the flowchart shown in FIG. 8, except for S115, the same steps as those shown in FIG. 4 are performed.

[0042] The initial path generation unit 133A includes an adjustment width setting unit 1331. In S115, which is the process executed by the adjustment width setting unit 1331, before generating the operation path, the adjustment width of the operation start time that satisfies the order constraint is set at the start and end points that are the targets of the operation path generation. The initial path generation unit 133A determines the safety distance between multiple robots based on the distance that the robot moves in this adjustment width time. The safety distance is greater than or equal to the distance traveled in the adjustable time and contributes to making it difficult for the robots to approach each other. When there is an adjustment time for each of the multiple robots, a method of setting each one or setting the maximum or minimum adjustment time can be adopted.

[0043] This safety distance is registered as one of the constraint conditions in the constraint condition registration unit 132. In S120, the initial path generation unit 133A determines the operation start times of multiple robots based on this constraint condition.

[0044] When determining the interference of the operations between robots during path generation, the initial path generation unit 133A determines whether the operation path shifted by the adjustable time interferes. When the operation paths interfere, the initial path generation unit 133A generates a non-interfering path even if the operation start time is shifted within the range of the adjustable time.

[0045] According to the second embodiment, in the constraint condition registration unit 132, ensuring a safety distance between a plurality of robots is registered as a constraint condition. This safety distance is determined based on the distance that the robot moves in the adjustable time, which is the adjustment range regarding the determined operation start time. According to this, even if the operation start time is shifted, it is possible to generate a path that is difficult to interfere. In addition, it is possible to provide a highly safe operation path so that the robots are less likely to approach each other by more than the distance traveled in the adjustable time. Further, even if the operation start time is corrected in the correction unit 134, it contributes to generating a non-interference path and minimizing the operation start time. Further, considering the search range of the operation start time, it is possible to generate a path in which the robots are spatially separated. The search range of the operation start time is defined as a range with the later of either the fastest operation start time that satisfies the constraints or the time when the previous operation of the same robot ended as the minimum value, and the operation start time when operating in the order determined at the time of the first path planning as the maximum value.

[0046] The initial path generation unit 133A generates a non-interference path for a plurality of robots based on the adjustable time, which is the adjustment range regarding the operation start time. According to this, even when the operation start time is shifted, it is possible to provide an operation path in which the robots are less likely to approach each other by more than the distance traveled in the adjustable time.

[0047] <The Third Embodiment> The third embodiment will be described with reference to FIGS. 9 and 10. According to FIGS. 9 and 10, the operation path generation device of the third embodiment will be described. For steps, configurations, operations, and effects not particularly described in the third embodiment, they are the same as those in the first embodiment, and only the differences from the first embodiment will be described below.

[0048] The third embodiment is different from the first embodiment in that it includes a start time search unit 1341 and an avoidance operation regeneration unit 1342, and in that it includes the processing steps of S132 and S134. According to the flowchart shown in FIG. 10, the same processing as the steps with the same reference numerals shown in FIG. 4 is performed except for S132 and S134.

[0049] The correction unit 134A includes a start time search unit 1341 and an avoidance operation regeneration unit 1342. In S132, which is a process executed by the start time search unit 1341, within a range that satisfies the order constraint, the operation start time of the teaching operation or the non-interference path generated in S120 is searched. In S132, while satisfying the order constraint, a range of operation start times where the evaluation value may improve is calculated. In S132, an operation start time where the evaluation value improves within the range of the operation start time is searched. This evaluation value is the same as the evaluation value used in the first embodiment described above.

[0050] In S134, which is a process executed by the avoidance operation regeneration unit 1342, an interference avoidance operation is regenerated in response to the change in the searched operation start time. In S134, for the changed operation start time, when there is no interference at the starting point but interference occurs between robots in the operations after the starting point, an interference avoidance operation is regenerated. The avoidance operation regeneration unit 1342 regenerates the interference avoidance operations of all the robots included between the robots where interference occurs or in the section to be regenerated. Also, when only regenerating between the robots where interference occurs, the paths of other robots may not be changed, and a determination may be made as to whether interference occurs during the path generation in S140.

[0051] The avoidance operation regeneration unit 1342 regenerates the interference avoidance operation based on the change in the operation start time of the non-interference path searched by the start time search unit 1341. For this reason, generation of a more appropriate interference avoidance operation can be achieved, contributing to advancing the operation start time. Therefore, the waiting time of each robot can be reduced, and the time for generating an appropriate operation path can be reduced.

[0052] The correction unit 134A regenerates the operations of a plurality of robots with the operation start time related to a specific robot as a fixed value. According to this, since the operation start time of a specific robot is fixed and the operations are regenerated, the amount of calculation can be reduced, and the time for generating an appropriate operation path can be reduced.

[0053] <Fourth Embodiment> The fourth embodiment will be described with reference to FIGS. 11 and 12. According to FIGS. 11 and 12, the operation path generation device of the fourth embodiment will be described. For steps, configurations, operations, and effects not specifically described in the fourth embodiment, they are the same as those in the first embodiment, and only the differences from the first embodiment will be described below.

[0054] The fourth embodiment is different from the first embodiment in that it includes a path search range setting unit 135 and a processing step of S1115. According to the flowchart shown in FIG. 12, except for S115, the same processing as the steps with the same reference numerals shown in FIG. 4 is performed.

[0055] PCS13 includes a path search range setting unit 135. In S115, which is the process executed by the path search range setting unit 135, before generating the operation path, a threshold value of the evaluation value of the operation path to be generated is set. In S115, when generating the operation path later, the operation path is searched within a range where the evaluation value does not deteriorate. Thereby, the path search range setting unit 135 sets the path search range. The processor 13 evaluates these, such as operation time, the movement amount of each joint, and the movement amount of the end effector such as the chuck part, by weighting them as the evaluation value.

[0056] PCS13 can reduce the search time by excluding from the search the range where the operation time deteriorates compared to the existing solution in path search. Also, PCS13 may be processed to update the set value of the path search range before the operation path is recalculated by the correction unit 134. As an example, PCS13 may set the path search range so as to reach the end point before the teaching operation of another robot ends. As an example, when generating the operation path after adjusting the operation start time, PCS13 may set the previous operation time and set the path search range so that the operation time does not increase. As an example, PCS13 may set the relationship of the arrival order between robots so that the constraint conditions regarding the operation order are observed.

[0057] The operation path generation device 1 includes a path search range setting unit 135 that searches for the range of the operation path based on the evaluation values of the operation paths for a plurality of robots. The path search range setting unit 135 searches for the operation paths of the plurality of robots such that the evaluation values for all the robots to be controlled are less than or equal to the evaluation value of a specific robot.

[0058] According to this, it is possible to secure the evaluation value of the robot that becomes the bottleneck, and to search for the operation paths of all the robots to be controlled. That is, it is possible to search for the operation paths of all the robots in a state where the path of the robot that becomes the bottleneck is appropriately secured, so that as a result, the overall operation path can be optimized.

[0059] When the evaluation value is the operation time, it is possible to provide an operation path that can optimize the overall operation time. In generating the operation paths of a plurality of robots, a robot may slow down its own path, thereby shortening the operation time of the robot that becomes the bottleneck. For this reason, it is possible to search for the operation path while evaluating how much it can be slowed down.

[0060] <Fifth Embodiment> The fifth embodiment will be described with reference to FIGS. 13 and 14. According to FIGS. 13 and 14, the operation path generation device of the fifth embodiment will be described. For steps, configurations, operations, and effects not particularly described in the fifth embodiment, they are the same as those in the first embodiment, and only the differences from the first embodiment will be described below.

[0061] The fifth embodiment is different from the first embodiment in that it includes an operation order alignment unit 136 and a processing step of S116. According to the flowchart shown in FIG. 14, except for S116, the same processing as the steps with the same reference numerals shown in FIG. 4 is performed.

[0062] The PCS 13 is provided with an operation sequence arranging unit 136. In S116 which is the process executed by the operation sequence arranging unit 136, a process is performed to arrange the registered teaching operations in chronological order for each robot so as to satisfy the order constraints. Thereby, it is possible to extract the teaching operations used by the initial path generation unit 133, and the start and end point information including the operation path start point and the operation path end point. Further, after the alignment process, it is possible to extract, as the target section for path generation, a section where the joint angles of the robot are different between the teaching operations, for example, for collision avoidance operations. As a method for arranging the registered teaching operations in chronological order for each robot so as to satisfy the order constraints, a greedy method or a topological sort can be used.

[0063] <Other Embodiments> The disclosure of this specification is not limited to the illustrated embodiments. The disclosure includes the illustrated embodiments and modifications by those skilled in the art based thereon. For example, the disclosure is not limited to the combination of components and elements shown in the embodiments, and can be implemented with various modifications. The disclosure can be implemented by various combinations. The disclosure can have additional parts that can be added to the embodiments. The disclosure includes those in which the components and elements of the embodiments are omitted. The disclosure includes the replacement or combination of components and elements between one embodiment and another embodiment. The disclosed technical scope is not limited to the description of the embodiments. The disclosed technical scope should be construed as being indicated by the description of the claims and including all changes within the meaning and scope equivalent to the description of the claims.

[0064] The devices and methods described in this disclosure may be implemented by a dedicated computer configured to program a processor to execute one or more functions embodied by a computer program. Alternatively, the devices and methods described in this disclosure may be implemented by dedicated hardware logic circuits. Or, the devices and methods described in this disclosure may be implemented by one or more dedicated computers configured by a combination of a processor that executes a computer program and one or more hardware logic circuits. Also, the computer program may be stored in a computer-readable non-transitory tangible recording medium as instructions to be executed by a computer.

[0065] The control device, the signal source, and the controlled object provide various elements. At least some of these elements can be referred to as blocks, modules, or sections. Further, the elements included in the control system are called functional means only when intentional.

[0066] <Disclosure of Technical Ideas> This specification discloses a plurality of technical ideas described in a plurality of claims listed below. Some claims may be described in a multiple dependent form that alternatively quotes a preceding claim in subsequent claims. Further, some claims may be described in a multiple dependent form that quotes a claim in another multiple dependent form. The claims described in these multiple dependent forms define a plurality of technical ideas.

[0067] <Technical Idea 1> An operation path generation device (1) that generates operation paths for a plurality of robots (21, 22), An instruction operation registration unit (131) in which an instruction operation for the robot is registered, A constraint condition registration unit (132) in which constraint conditions including at least order constraints on the operation of the robot are registered; An initial path generation unit (133) that determines the operation start time of the robot based on the teaching operation and the constraint conditions, generates a plurality of interference avoidance paths for the robot between two teaching operations, and generates an operation path for the plurality of robots; A correction unit (134) that corrects the operation start time of the robot based on the generated operation path; An operation path generation device comprising:

[0068] <Technical Idea 2> In the constraint condition registration unit, ensuring a safety distance between the plurality of robots determined based on the distance traveled by the robot within an adjustable time that is an adjustment range related to the determined operation start time is registered as the constraint condition. The operation path generation device according to Technical Idea 1.

[0069] <Technical Idea 3> The initial path generation unit generates a non-interference path for the plurality of robots based on an adjustable time that is an adjustment range related to the determined operation start time. The operation path generation device according to Technical Idea 1 or Technical Idea 2.

[0070] <Technical Idea 4> The correction unit fixes the operation start time related to a specific robot as a fixed value and regenerates the operations of the plurality of robots. The operation path generation device according to any one of Technical Ideas 1 to 3.

Explanation of Signs

[0071] 1... Operation path generation device, 21, 22... Robots, 131... Teaching operation registration unit 132... Constraint condition registration unit, 133... Initial path generation unit, 134... Correction unit

Claims

1. An operation path generation device (1) that generates operation paths for a plurality of robots (21, 22), an instruction operation registration unit (131) in which the instruction operations for the robots are registered, a constraint condition registration unit (132) in which constraint conditions including at least order constraints on operations are registered for the robots, an initial path generation unit (133) that determines the operation start time of the robots based on the instruction operations and the constraint conditions, generates interference avoidance paths for the plurality of robots between two of the instruction operations, and generates operation paths for the plurality of robots, a correction unit (134) that corrects the operation start time of the robots based on the generated operation paths, and an operation path generation device comprising the same.

2. The operation path generation device according to claim 1, wherein in the constraint condition registration unit, ensuring a safety distance between the plurality of robots determined based on the distance traveled by the robots within an adjustable time which is an adjustment range related to the operation start time is registered as the constraint condition.

3. The operation path generation device according to claim 1, wherein the initial path generation unit generates non-interference paths for the plurality of robots based on an adjustable time which is an adjustment range related to the operation start time.

4. The operation path generation device according to any one of claims 1 to 3, wherein the correction unit fixes the operation start time of a specific one of the robots as a fixed value and regenerates the operations of the plurality of robots.

5. Comprising a path search range setting unit that searches for a range of the operation path based on an evaluation value of the operation path for the plurality of robots, wherein the path search range setting unit searches for the operation paths of the plurality of robots such that the evaluation values for all the robots to be controlled are less than or equal to the evaluation value of a specific robot.

6. An operation path generation method for generating operation paths for a plurality of robots (21, 22), determining the operation start time of the robots based on the registered instruction operations of the robots and the constraint conditions registered including at least order constraints on operations for the robots, generating interference avoidance paths for the plurality of robots between two of the instruction operations, and generating operation paths for the plurality of robots (S120), and correcting the operation start time of the robots based on the generated operation paths (S130). An operation path generation method including

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