This application is based upon and claims the benefit of priority from Japanese Patent Application No. 2013-055373, filed Mar. 18, 2013, the entire contents of which are incorporated herein by reference.
1. Field
The present disclosure relates to a robot system, a control apparatus, and a method of manufacturing a work piece.
2. Description of the Related Art
In recent manufacturing lines, for example, as disclosed in Japanese Patent Laid-Open Publication No. 2010-188459, a component kit made by collecting various kinds of component sets (referred to as “mixed component”) needed for assembling a product, on a component tray, are formed, and the corresponding formed component kit is supplied to a robot for performing an assembling operation. In a manufacturing method using the component kit, the assembling operation is performed by picking up components in the component kit according to a predetermined assembling sequence.
An aspect of the present disclosure is to provide a robot system including: a component loading portion where plurality of kinds of components needed for assembling a product are loaded; a robot configured to pick up the components from the component loading portion and assemble the picked-up components; and a control apparatus configured to control an operation of the robot, wherein the control apparatus includes a first storage unit configured to store information indicating a predetermined assembling sequence when the components are assembled, and controls the operation of the robot such that the robot picks up the components from the component loading portion in order according to the assembling sequence and assembles the components, and when the robot fails to pick up the component according to the assembling sequence, the control apparatus controls the operation of the robot such that the robot first picks up the component having a high picking-up possibility and first assembles corresponding picked-up component according to the assembling sequence between the picked-up components, and changes a picking-up condition and controls the operation of the robot such that the robot picks up the components before assembling based on the changed picking-up condition and assembles the components.
Hereinafter, embodiments of a robot system, a control apparatus, and a method of manufacturing a work piece will be described in detail with reference to the accompanying drawings. Further, in the description of the drawings, the same elements will be designated by the same reference numerals and a duplicate description thereof will be omitted. Further, the drawings and the related description, which will be described below, are provided for illustrative purposes to describe a robot system, a control apparatus, and a method of manufacturing a work piece, and do not limit the scope of the present invention. Further, dimensions, etc of illustrated parts may be different from actual dimensions of a robot system, a control apparatus, and a method of manufacturing a work piece.
(An Overall Configuration of a Robot System 1)
First, an overall configuration of the robot system 1 will be described.
In the component loading tray 30, various kinds of components needed for assembling a product, that is, mixed components are loaded.
When a predetermined assembling is performed by using the components 31 to 35 illustrated in
The image pickup apparatus 40 picks up an image of the component loading tray 30. The image pickup apparatus 40 has only to pick up an image of an object, and may be configured by, for example, a CCD camera, a stereo camera, a distance image sensor, or a combination of them.
The temporary installation table 50 and the assembling table 60 correspond to general working tables in manufacturing lines. The temporary installation table 50 is a table for temporarily loading a component picked up by the picking robot 21. The assembling table 60 is a table in which the assembling robot 22 performs an assembling operation by using the component picked up by the picking robot 21.
In the robot system 1 having a configuration illustrated in
(The Control Apparatus 10)
Next, the control apparatus 10 will be described. The control apparatus 10 controls an operation of the robot 20.
As illustrated in
The storage unit 120 stores data needed for performing various controls of the control apparatus 10, and includes an assembling sequence storage unit 121 (first storage unit) and a next step executable-or-not information storage unit 122 (second storage unit). The assembling sequence storage unit 121 stores information indicating a predetermined assembling sequence when the components 31 to 35 are assembled. As described above, a predetermined assembling sequence for assembling is set for each of the components 31 to 35, and the assembling sequence storage unit 121 stores the information indicating the predetermined assembling sequence. In the above example, the assembling sequence storage unit 121 stores information indicating an assembling sequence in the order of components 31, 32, 33, 34, and 35.
The assembling sequence storage unit 121 stores information indicating an assembling sequence (hereinafter, referred to as “sequence for a part of components”) for a part of components on the component loading tray 30 as well as information indicating an assembling sequence (hereinafter, referred to as “sequence for all components”) for all components on the component loading tray 30. For example, for the components 33, 34, and 35, the storage unit 120 stores information indicating an assembling sequence in the order of components 33, 34, and 35. Although a sequence for all components with respect to the components 33, 34, and 35 and a sequence for a part of components with respect to the components 33, 34, and 35 coincide with each other in this example, they are not limited thereto, and they may not coincide with each other. That is, for example, a sequence for a part of components may be in the order of the components 34, 33, and 35 according to a kind of a completed product or a condition of an assembling operation.
The next step executable-or-not information storage unit 122 stores information indicating whether an assembling process can proceed to a next step in an assembling sequence for each component. “Whether an assembling process can proceed to a next step in an assembling sequence” implies whether it is possible to partially start assembling of a corresponding component, which has been picked up, even when a component in a prior turn in an assembling sequence has not been picked up.
For example, in the case of the components 31 to 35 illustrated in
Meanwhile, in a case of the component 32, when the component 31 is not picked up, the assembling process cannot proceed to a next step. This is because, in a case where the component 31 is not picked up, even when the component 32 is picked up and the component 33 is then picked up, there is no assembling operation to be directly performed between the components 32 and 33. In this case, the component 32 corresponds to “a component disabling the assembling process to proceed to a next step”, and the next step executable-or-not information storage unit 122 stores information indicating this purpose.
The control unit 130 receives various inputs from the image input unit 110 and the storage unit 120, and serves to control an operation of the robot 20 based on the corresponding inputs. The control unit 130 generally performs a control such that the robot 20 picks up the components 31 to 35 from the component loading tray 30 in order according to a predetermined assembling sequence and assembles the components. Meanwhile, when the robot 20 fails to pick up one of the components according to the predetermined assembling sequence, the control unit 130 controls the operation of the robot 20 such that the robot 20 first picks up a component having a high picking-up possibility and enabling the assembling process to proceed to a next step, and first assembles the corresponding picked-up component according to the assembling sequence between the corresponding picked-up components. Thereafter, the control unit 130 changes a picking-up condition, and controls the operation of the robot 20 such that the robot 20 picks up components before assembling based on the changed picking-up condition to assemble the components.
In order to implement the above operations, the control unit 130 functionally includes a picking-up success-failure determination unit 131, a picking-up possibility determination unit 132, an instruction output unit 133, a picking-up condition change unit 134, and an assembling completion determination unit 135.
The picking-up success-failure determination unit 131 determines whether the robot 20 succeeds to pick up a component. The picking-up success-failure determination unit 131 can perform this determination based on, for example, information received from a sensor 24 (See
When the robot 20 fails to pick up one of the components according to the predetermined assembling sequence, the picking-up possibility determination unit 132 determines a possibility of success in picking up a component in a next turn in the corresponding assembling sequence. The possibility of success in picking up the component is determined based on, for example, a shape, a posture, a position, and the like of the corresponding component. When scores of each of the shape, the posture, the position, and the like of the corresponding component are calculated and the total score exceeds a predetermined threshold value, the picking-up possibility determination unit 132 determines that the corresponding component has a high possibility of success in being picked up. The picking-up possibility determination unit 132 outputs information indicating the determination result to the instruction output unit 133.
The instruction output unit 133 generates an instruction for picking up and assembling components and outputs the instruction to the robot 20. The robot 20 picks up and assembles the component designated by the instruction from the instruction output unit 133. A driving unit (not shown) for driving the robot 20 based on the instruction from the instruction output unit 133 may be separately provided. In general, the instruction output unit 133 generates a picking-up instruction and outputs the instruction to the robot 20, such that the robot 20 picks up all of components on the component loading tray 30 in order according to the predetermined assembling sequence. As an example of
Meanwhile, when receiving, from the picking-up success-failure determination unit 131, information indicating the reason of failure of the robot 20 in picking up one of the components, the instruction output unit 133 generates a picking-up instruction and outputs the instruction to the robot 20, such that the robot 20 first picks up a component having a high picking-up possibility and enabling the assembling process to proceed to a next step, and loads the picked-up component on the temporary installation table 50. Herein, the determination on which component has a high picking-up possibility is performed based on an output signal from the picking-up possibility determination unit 132. Further, the determination on whether the corresponding component is a component enabling the assembling process to proceed to a next step is performed with reference to the next step executable-or-not information storage unit 122. Further, the instruction output unit 133 generates an assembling instruction and outputs the instruction to first assemble picked-up components loaded on the temporary installation table 50 according to an assembling sequence between the corresponding picked-up components.
In an example of
However, the instruction output unit 133 does not generate a picking-up instruction for first picking up the component 32. This is because it is determined that the component 32 corresponds to a component disabling the assembling process to proceed to a next step. The instruction output unit 133 can perform this determination with reference to the next step executable-or-not information storage unit 122.
Further, the instruction output unit 133 generates an assembling instruction and outputs the instruction to robot 20 such that the robot 20 first assembles the corresponding picked-up components 34 and 35 according to the assembling sequence between the components 34 and 35 which are the corresponding picked-up components. Further, the instruction output unit 133 can acquire information indicating the assembling sequence (sequence for a part of components) between the components 34 and 35 with reference to the assembling sequence storage unit 121. Meanwhile, since the component 32 has a high picking-up possibility, the instruction output unit 133 may generate a picking-up instruction for first picking up the component 32 and loading the component 32 on another temporary installation table (not shown).
The picking-up condition change unit 134 changes a picking-up condition of the robot 20. When the robot 20 fails to pick up one of the components according to a predetermined assembling sequence, the picking-up condition change unit 134 changes the picking-up condition after the component in a next step is first picked up as described above. After the picking-up condition is changed by the picking-up condition change unit 134, the instruction output unit 133 generates a picking-up instruction and an assembling instruction and outputs the instructions to the robot 20 such that the robot 20 picks up components before assembling based on the changed picking-up condition to assemble the component. In the above example, after the picking-up condition is changed, the instruction output unit 133 generates a picking-up instruction and an assembling instruction and outputs the instructions to the robot 20 such that the robot 20 picks up the components 31 to 33 based on the changed picking-up condition to assemble the components 31 to 33. The instruction output unit 133 may generate a picking-up instruction and an assembling instruction such that the robot 20 moves the corresponding picked-up components 31 to 33 to the assembling table 60 and assembles the components 31 to 33 with the components 34 and 35 which are previously assembled at the temporary installation table 50.
As a method of changing the picking-up condition, the picking-up condition change unit 134 may change a lighting 70 (See
As another method of changing the picking-up condition, the picking-up condition change unit 134 may change an initial position of the robot 20 for picking up the components. In this case, the picking-up condition change unit 134 may change the picking-up condition by outputting, to the robot 20, an instruction having a purpose for changing the initial position to another predetermined position.
As yet another method of changing the picking-up condition, the picking-up condition change unit 134 may shuffle components remaining in the component loading tray 30 once. In this case, another robot for the shuffling may be additionally provided, or the robot 20 may perform the shuffling. Otherwise, the picking-up condition change unit 134 outputs an alarm for the shuffling, and an operator may perform the shuffling.
The assembling completion determination unit 135 determines whether the assembling by the robot 20 is completed. As a method of determining the assembling completion, the assembling completion determination unit 135 compares an image of the component loading tray 30 before components are loaded on the component loading tray 30 with an image of the component loading tray 30 picked up at a time point when the corresponding determination is performed, and when a coincidence degree of the two images is larger than or equal to a predetermined threshold value, the assembling completion determination unit 135 may determine that the assembling is completed.
As another method of determining the assembling completion, a predetermined mark is decorated at each of positions where the components are loaded on the component loading tray 30, and when the marks corresponding to each of the components are perceived to be more than or equal to a predetermined threshold value from the image of the component loading tray 30 picked-up at a time point when the corresponding determination is performed, the assembling completion determination unit 135 may determine that the assembling is completed.
As yet another method of determining the assembling completion, a place where the components of the component loading tray 30 are loaded is formed in grid patterns, and when the grid patterns are perceived to be more than or equal to a predetermined threshold value from the image of the component loading tray 30 picked up at a time point when the corresponding determination is performed, the assembling completion determination unit 135 may determine that the assembling is completed.
Hereinabove, although the robot system 1 according to the present embodiment has been described, a desired product (work piece) can be manufactured by using the robot system 1. The work piece corresponds to all products using a work receiving processing such as carrying or assembling by the robot system 1, or the work itself. For example, the work piece includes components such as a bolt or assemblies such as a vehicle.
Next, an operation and an effect of the robot system 1 according to the present embodiment will be described. In accordance with the robot system 1 according to the present embodiment, the control apparatus 10 generally performs a control such that the robot 20 picks up components from the component loading tray 30 in order according to an assembling sequence and assembles the components. Meanwhile, when the robot 20 fails to pick up one of the components according to the predetermined assembling sequence, the control apparatus 10 controls the operation of the robot 20 such that the robot first picks up a component which has a high picking-up possibility, and first assembles the corresponding picked-up components according to the assembling sequence between the corresponding picked-up components. Thereafter, the control apparatus 10 changes a picking-up condition, and controls the operation of the robot 20 such that the robot 20 picks up components before assembling based on the changed picking-up condition to assembles the components.
By the control described above, when the robot fails to pick up a specific component, it is possible to prevent repeated picking up of the corresponding component until the corresponding component is successfully picked up. As a result, it is possible to prevent deterioration of work efficiency by unnecessary lengthening of a work time, which may be caused by repeated trying of picking up the components having a low picking-up possibility. Further, since the control apparatus 10 controls to first pick up the components having a high picking-up possibility, it is possible to clearly prevent repeated trying of picking up the components having a low picking-up possibility. Further, since the control apparatus 10 changes the picking-up condition and controls to retry to pick up the components, it is possible to prevent repeated trying of picking up the components in a low picking-up possibility state.
Further, in the related art, in the case of failing in picking up a component in a turn of the assembling sequence, it is usual that the assembling process does not proceed to the next step without the component which the robot 20 fails to pick up. As a result, the robot 20 tries to pick up the component until successfully picking up the component. Accordingly, work time is unnecessarily lengthened, and when a long time is spent until the robot 20 succeeds in picking up the component, work efficiency deteriorates. Meanwhile, in accordance with the embodiment of the present invention described above, the work efficiency of the assembling operation may be improved.
Further, in accordance with the present embodiment, there is provided a detailed method of changing the picking-up condition. That is, it is possible to seek a possibility to improve a picking-up success rate when the robot 20 retries to pick up the component, by changing brightness or the like of the lighting 70. Further, it is possible to seek a possibility to improve a picking-up success rate when retrying picking-up, by changing the initial position of the robot 20 for picking up the components. Furthermore, it is possible to seek a possibility to improve a picking-up success rate when the robot 20 retries to pick up the component, by shuffling the components remaining in the component loading tray 30 once.
Further, in accordance with the present embodiment, when the robot 20 fails to pick up one of the components according to the predetermined assembling sequence, the control apparatus 10 controls the operation of the robot 20 such that the robot 20 first picks up a component having a high picking-up possibility and enabling the assembling process to proceed to a next step. The component enabling the assembling process to proceed to a next step is first picked up and the assembling operation of the component is first performed, so as to further improve the work efficiency.
Further, in accordance with the present embodiment, there is provided a detailed method of determining whether the assembling by the robot 20 is completed. That is, the assembling completion determination unit 135 compares an image of the component loading tray 30 before the components are loaded on the component loading tray 30 with an image of the component loading tray 30 picked up at a time point when the corresponding determination is performed, and then when a coincidence degree of the two images is larger than or equal to a predetermined threshold value, the assembling completion determination unit 135 may determine that the assembling is completed. By this method, the determination of the assembling completion is promptly performed by using a simple configuration.
Further, a predetermined mark is decorated at each of positions where the components are loaded on the component loading tray 30, and when the marks corresponding to each of the components are perceived to be more than or equal to a predetermined threshold value from the image of the component loading tray 30 picked up at a time point when the corresponding determination is performed, the assembling completion determination unit 135 may determine that the assembling is completed. By this method, for example, since it is possible to prevent misperception of a flaw on the component loading tray 30 as a component, the determination of the assembling completion may be correctly performed.
Further, a place where the components of the component loading tray 30 are loaded is formed in grid patterns, and when the grid patterns are perceived to be more than or equal to a predetermined threshold value from the image of the component loading tray 30 picked up at a time point when the corresponding determination is performed, the assembling completion determination unit 135 may determine that the assembling is completed. By this method, the determination of the assembling completion may be correctly performed while the apparatus is simply configured.
Hereinabove, although the embodiments of the present invention have been described, the present invention is not limited thereto.
For example, the robot 20 according to the above embodiments is not limited to a single arm type robot illustrated in
Further, the components 31 to 35 illustrated in the
Indeed, the novel devices and methods described herein may be embodied in a variety of other forms; furthermore, various omissions, substitutions and changes in the form of the devices and methods described herein may be made without departing from the spirit of the inventions. The accompanying claims and their equivalents are intended to cover such forms or modification as would fall within the scope and spirit of the inventions.
Certain aspects, advantages, and novel features of the embodiment have been described herein. It is to be understood that not necessarily all such advantages may be achieved in accordance with any particular embodiment of the invention. Thus, the invention may be embodied or carried out in a manner that achieves or optimizes one advantage or group of advantages as taught herein without necessarily achieving other advantages as may be taught or suggested herein.
Number | Date | Country | Kind |
---|---|---|---|
2013-055373 | Mar 2013 | JP | national |