JPH06339883A - Stopping positioning control method and device for picking device and position control method and device for picking device and picking device - Google Patents

Abstract

PURPOSE:To secure operation necessary for respective operations, and increase cycle time by carrying out stopping position control on respective shafts with every continuous operation according to the preset content in a picking device having an orthogonal triaxial manipulator. CONSTITUTION:A picking device having an orthogonal triaxial manipulator carries an object 14 from a magazine 2 of a rack 1 by a roller conveyor 4 through a delivery bucket 3. On the other hand, a travel carriage 5 is driven through a timing belt 7 by a traveling motor 6. A raising-lowering body 9 is driven through a timing belt 11 by a raising-lowering motor 10, and a hand part 12 is installed on an arm shaft 13 capable of advancing and retreating, and the object 14 is gripped. In this case, when operation up to a delivery box from a delivery shelf is carried out continuously, a stopping positioning accuracy value is set individually in three shafts with every operation. Stopping position control on respective shafts with every operation is carried out according to the preset content.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a picking device which requires a high response drive and high speed vibration control, and has a limit in controlling the vibration of a mechanical system remarkably generated at a stop due to high acceleration / deceleration. Under certain circumstances, it is necessary to secure the required stop positioning accuracy for each operation, and to end the positioning completion operation time that depends on the vibration establishment time as quickly as possible to improve the cycle time and improve the picking operation capacity. The present invention relates to a picking device stop positioning control method and a picking device.

[0002]

2. Description of the Related Art As a method of improving the cycle time in a conventional picking device, acceleration / deceleration is increased,
Higher speed or damping control by S-pattern acceleration / deceleration pattern is used. Further, the positioning control uniformly defines the stop positioning accuracy of each operation during the repetitive operation, and therefore, it is inevitably necessary to speed up the positioning process.

[0003]

In the stop positioning control method for the picking device of the prior art described above, when the orthogonal triaxial manipulator is stopped moving at high acceleration / deceleration and high speed, the rigidity of the mechanical system is involved. Vibration of the manipulator occurs, and the time when the amplitude value of the vibration converges to the stop positioning accuracy, that is, the positioning completion operation time greatly affects the cycle time. There, the stop positioning operation is executed for each operation until the manipulator picks the object from the delivery shelf and puts it into the shipping box, and the cycle time is affected by the number of operations, but the conventional technique If the positioning accuracy for each operation is uniformly set as described above, each axis will affect the cycle time of the picking operation in an attempt to achieve the target positioning accuracy in all the operations. There was a problem that it was difficult to improve.

An object of the present invention is, in a picking device using an orthogonal three-axis manipulator, not a uniform stop positioning accuracy for each operation as in the prior art, but an operation requiring a positioning accuracy strictly. An object of the present invention is to provide a stop positioning control method for a picking device and a picking device capable of ensuring the precision required for each motion by distinguishing it from rough motions and improving the cycle time of the picking motion.

[0005]

In order to achieve the above object, a stop positioning control method for a picking device and a picking device according to the present invention are a picking device using an orthogonal three-axis manipulator. In order to continuously execute the series of operations up to, picking cycle is set by setting the stop positioning accuracy required for each operation instead of setting the stop positioning accuracy for each operation evenly. This is to make it possible to improve the time.

Further, the operation of the orthogonal three-axis manipulator reaching the position for handling the picking object is defined as a rank which requires the most stop positioning accuracy, and a hierarchical structure having this as a vertex is constructed and each operation processing is performed. By assigning the identifier of each layer to be defined at the beginning of the, the constant of the positioning accuracy of the operation is taken out from the table that is set according to the function of the picking device and set. By initially setting the stop positioning accuracy of, the stop positioning accuracy for each operation of the repetitive picking operation can be efficiently set without setting each time.

[0007]

The stop positioning control method for the picking device, the picking device, and the like do not make the stop positioning accuracy for each operation uniform, but individualize according to the operation to increase the cycle time. That is, each operation from the delivery shelf to the shipping box is selected in consideration of the importance, the relationship between the front and back operations, and the operation axis, and the positioning accuracy is set accordingly. As a result, it is possible to differentiate between an operation that requires strict accuracy and an operation that may be rough, rather than a uniform target positioning accuracy, and it is possible to improve the cycle time of the picking operation.

The stop positioning accuracy of each operation in the repetitive picking is layered in order to avoid uniform positioning control and to facilitate selection of accuracy constants. The number of layers is regulated by the performance of the picking device, the handling method, the picking object, the number of control axes, etc., but it depends on the number of individual operations of the picking device from shipping to shipping, Is 1 and the maximum is the total number of operations. The identifier attached to the beginning of each operation process is used to determine the stop positioning accuracy constant determined from the rank of the hierarchical structure, and is used for the positioning completion process of each operation, and the vibration amplitude value of the mechanical system generated at the time of stop is Positioning is completed when the stop positioning accuracy constant converges below.

[0009]

Embodiments of the present invention will be described below with reference to FIGS. 1 to 9. FIG. 1 is a flow chart of a control algorithm showing an embodiment of a stop positioning method for a picking device according to the present invention. In FIG. 1, the control means of the picking device is
When the picking operation is started, first, in the initial setting of the process S1, the operation of the orthogonal three-axis manipulator reaching the position for handling the picking target is set as the rank requiring the highest stop positioning accuracy, and this is set as the apex. A table for setting the constant of the positioning accuracy of the operation according to the function of the picking device by constructing a hierarchical structure and adding the identifier of each hierarchy defined at the beginning to the beginning of each operation processing Remove from the table and set. By initially setting the stop positioning accuracy of each axis using such means, the stop positioning accuracy for each operation of the repeated picking operation can be efficiently set without setting each time. Therefore, in the identifier discrimination in the next process S2, the identifier assigned to the head is discriminated for each operation. As a result, when the identifier n (n = 1 to n) is determined in the process S3, the stop positioning accuracy A _n (A _1-
A _n ). As a result, in the moving process of process S5,
After performing the movement process of the operation, the positioning process with the stop positioning accuracy A _n (A _{1 to} A _n ) is performed in the stop positioning process of the next process S6, and the operation is ended.

FIG. 2 is a table of stop positioning accuracy constants set in FIG. In FIG. 2, for each operation (moving operation) M _{1 to} M _n of the picking device, each identifier 1
~ _N and stop positioning accuracy A _{1 to} A _n are displayed in a table. The hierarchization of the stop positioning accuracy of each operation in this repeated picking is constructed in order to avoid uniform positioning control and to easily select the stop positioning accuracy constants A _{1 to} A _n . The number of layers is regulated by the performance of the picking device, the handling method, the picking target and the number of control axes, etc., but specifically, depending on the number of individual operations from picking up to shipping of the picking device, The minimum is 1, and the maximum is the total number of operations. The identifiers 1 to n added to the head of each operation process determine the stop positioning accuracy constants A _{1 to} A _n determined from the rank of the hierarchical structure, and are used for the positioning completion process of each operation M _{1 to} M _n. Is
When the vibration amplitude value of the mechanical system generated at the time of stop converges below the stop positioning accuracy constants A _{1 to} A _n , the positioning is completed.

FIG. 3 is a perspective view of a mechanism showing an embodiment of a picking device using an orthogonal triaxial manipulator according to the present invention. Fig. 3 shows a CD picking device in which the picking target is a compact disc CD. In the figure, 1 is a rack having 16 rows and 6 shelves of shelves, and 2 is a deferred storage of up to 50 CDs. Possible magazines, 3 are shipping buckets for shipping the released CDs, 4
Is a roller conveyor that conveys shipping buckets. 5 is a traveling carriage, 6 is a traveling motor, 7 is a timing belt, and the traveling carriage 5 is a traveling motor and a timing belt 7.
Driven by. Reference numeral 8 is a frame that supports the traveling system. 9
Is a lifting body, 10 is a lifting motor, 11 is a timing belt, and the lifting body 9 is driven by a lifting motor 10 and a timing belt 11. Reference numeral 13 is an arm shaft for advancing and retracting in the rack direction, 12 is a hand portion for gripping a CD using an air cylinder, and 14 is a CD.

FIG. 4 is a front view of the rack 1 of FIG. In FIG. 4, the rack 1 has 16 rows and 6 shelves, and a magazine 2 on which up to 50 CDs 14 can be placed is placed on each rack. Each of the 16 shelves and 6 shelves is converted from the shelving coordinates of each shelving of each row to (X, Z) coordinates.

FIG. 5 is an internal side view of the rack 1 of FIG. In FIG. 5, up to 50 CDs 14 can be placed on each of the 16 shelves and 6 shelves in the rack 1 as shown in the figure. It is released and dropped into the upper shipping bucket 3.

FIG. 6 is a controller block diagram of the control panel of the picking device of FIG. In FIG. 6, reference numeral 15 is an arm motor, 16 is a control panel (controller), 17 is a position controller, 18 is a sequencer, 19 is a positioning controller, and the position controller 17 is the sequencer 1.
8 and a positioning controller 19. Reference numeral 20 is a servo amplifier of the traveling motor 6, 21 is a servo amplifier of the arm motor 15, and 22 is a servo amplifier 22 of the lifting motor 10. The control board (controller) 16 is connected to the host computer 23 via the Ethernet 24.

The operation of FIG. 6 will be described. When the automatic driving condition is established, a preparation completion signal is sent to the host computer 23. The control panel 16 receives the work data (data indicating the shelf coordinates, data indicating the number of gripped sheets, data indicating the carry-out destination bucket) from the host computer 23 via the Ethernet 24, and the data is correct (correction error occurs). Or not)
Check if, and if correct, set the automatic operation holding condition and perform the first picking. If the data transfer fails, a resend request is issued. If the next work data is not transmitted from the host computer 23 during the picking operation, the mechanical brake of the servo motor is operated and stopped after a certain time. If it has been transmitted, the control panel 16 repeats the same operation as described above.

The position controller 17 in the control panel 16
The sequencer 18 comprises a sequencer 18 and a positioning controller 19. The sequencer 18 operates in each of the operations M _{1 to} M described in this embodiment.
_It has a processing function based on ₁₀ sequences and identifiers, and the positioning controller 19 controls the rotation of the servomotors 6, 15 and 10 via the servo amplifiers 20, 21 and 22 in accordance with this sequence and its processing. The external sensors that interface with the sequencer 18 are an overflow detection sensor that detects an overflow outside the movement limit range in the rack, and a CD as an object.
It refers to a sensor for detecting whether or not there is an emergency stop sensor, etc. (In addition, it is bidirectional as shown because it includes various displays and indicator lamps). Upon receiving these sensor outputs, various processing such as a stop command and interruption is performed. The absolute position data input to the positioning controller 19 is the absolute position of various movements calculated from the rotation amount of each servo motor, and is used as a feedback amount. Also,
A mechanical brake for emergency stop is added to each servo motor 6, 10, 15.

FIG. 7 is an operation vector diagram by the control panel (controller) of FIG. 6 in which a series of flows from the picking-up device to the shipment of the picking device of FIG. 3 are divided for each operation. Figure 6
In the figure, X, Y, and Z indicate a traveling axis, an arm axis, and a lifting axis of three orthogonal axes, respectively. First, M ₁ is a designated shelving shelf moving operation of moving from the origin position to the arm origin position of the designated magazine 2, whereby the traveling axis X and the elevating axis Z simultaneously operate. M ₂ and M ₃ are movements from the arm origin position to the gripping position of the designated CD 14, M ₂ is full speed movement, and M ₃ is creep speed movement. M ₄ is a CD gripping operation in which the hand portion 12 grips a CD, and M ₅ is a CD 2 in the magazine 2
The arm axis Y and the elevating axis Z are simultaneously operated by the CD pulling operation of pulling up from. M ₆ is C gripped from inside rack 1.
It is an arm shelving shelf origin retreat operation for retracting D to the arm origin position, and M ₇ is a traveling operation for the designated shipping bucket moving operation to the arm origin position of the designated shipping bucket 3 and a simultaneous movement operation of the lifting and lowering axes. is there. M ₈ is an arm shipping bucket advancing operation that is a movement operation from the arm origin position to the CD loading position of the shipping bucket 3, M ₉ is a CD opening operation that opens the hand portion 12, and M ₁₀ is an arm. Move back to the origin position
This is the backward movement of the shipping bucket. These series of operations are repeatedly executed.

FIG. 8 is a control panel (controller) 16 shown in FIG.
3 is a table of the stop positioning accuracy constant setting table of FIG. In FIG. 7, the positioning controller 19 of the position controller 17 of the control panel (controller) 6 performs stop positioning processing in consideration of the vibration set time of the mechanical system by the moving operation during the series of CD picking operation flow of FIG. Is performed by M ₁ , M ₂ , M ₃ , M ₅ , M ₆ ,
There are eight operations of M ₇ , M ₈ , and M ₁₀ . These operations are classified into three types of stop positioning accuracy according to the required range, and an identifier is given to each of them. If the identifier 1 is selected in each operation process, the stop positioning accuracy of ± 1 mm is automatically set and used in the positioning process. Similarly, the identifier is 2
Then, ± 3 mm is automatically set, and if the identifier is 3, ± 5 mm is automatically set. Here, the operations to which the identifier 1 is assigned are M ₁ and M ₃ , the operations to which the identifier 2 is assigned are M ₂ and M ₄ , and the operations to which the identifier 3 is assigned are M ₆ , M ₇ , M ₈ and M. _Ten
Is. In the present embodiment, the reason for this ranking is that the CD gripping action is the highest rank, the action inside the rack 1 is the next rank, and the action outside the rack 1 is the lowest rank.

FIG. 9 is an operation time chart corresponding to each operation of FIG. 7 by the control panel (controller) of FIG. 6 in which a series of flow from the warehousing to shipping of the picking apparatus of FIG. 3 is divided for each operation. In FIG. 9, the traveling motor 6 of the orthogonal three-axis manipulator by the control panel (controller) of FIG. 6 from the delivery to the shipment of the picking device of FIG.
The speed V of the arm motor 15 and the lifting motor 10 is shown.

Here, the positioning processing time before and after using the processing method of the stop positioning control method of the above embodiment will be compared. This stop positioning processing time is almost equal to the residual vibration time of the mechanical system generated at the time of stop. The residual vibration time when the stop positioning accuracy is ± 1 mm is T _s1 , the residual vibration time when the stop positioning accuracy is ± 3 mm is T _s2 , and the stop positioning accuracy is ±
The residual vibration time at 5 mm is T _s3 , the total positioning processing time before and after using the processing method of this embodiment is Tb,
Assuming Ta, Tb = T _s1 × 8 Ta = [T _s1 × 2] + [T _s2 × 2] + [T _s3 × 4]. Here, from the actual measurement results, the average T _s1 ,
Substituting 0.2 seconds, 0.1 seconds, and 0.05 seconds for T _s2 and T _s3 , respectively, Tb = 1.6 seconds and Ta = 0.8 seconds. Thus, by setting the stop positioning accuracy for each operation of the present invention instead of uniformly setting it, the cycle time can be further shortened, and the efficiency of the picking apparatus can be improved.

In addition to the CD, it can be applied to an FD and various parts.

[0022]

As described above, according to the stop positioning control method of the picking device and the picking device of the present invention,
In a picking system such as each operation time is short and repetitive operation, compared with the conventional control method that uniformly defines the stop positioning accuracy of each operation during repetitive operation,
Since the positioning accuracy can be set for each operation, it is effective in increasing the cycle time and in improving the capability of the picking system that requires efficient use of time.

[Brief description of drawings]

FIG. 1 is a flowchart of a control algorithm showing an embodiment of a stop positioning control method for a picking device according to the present invention.

FIG. 2 is a stop positioning accuracy constant table set in FIG.

FIG. 3 is a perspective view of a mechanism showing an embodiment of the picking device of the present invention.

FIG. 4 is a front view of the rack of FIG.

5 is an internal side view of the rack of FIG.

6 is a configuration diagram of a control panel of the picking device of FIG.

FIG. 7 is an operational flowchart of the picking device of FIG.

8 is a stop positioning accuracy constant setting table table for each operation shown in FIG. 7. FIG.

9 is an operation time chart of the picking device of FIG.

[Explanation of symbols]

1 Rack 2 Magazine 3 Shipping Bucket 4 Roller Conveyor 5 Traveling Vehicle 6 Traveling Motor 7, 11 Timing Belt 8 Traveling Frame 9 Elevating Body 10 Elevating Motor 12 Hand 13 Arm Axis 14 CD 15 For Arm Motor 16 Control panel 17 Position controller 18 Sequencer 19 Positioning controller 20, 21, 22 Servo amplifier 23 Host computer 24 Ethernet M ₁ Designated shelving shelf moving operation M ₂ arm Shelving shelf full speed forward operation M ₃ arm Detaching shelf clear flop forward movement M ₄ CD gripping operation M ₅ CD pulling operation M ₆ A - No unloading shelf origin retraction M ₇ specify shipping bucket movement M ₈ A - No shipping bucket forward movement M ₉ CD opening operation M ₁₀ A - No shipping Bucket retract operation

Claims (13)

[Claims] 1. In a picking device using an orthogonal three-axis manipulator, when performing a series of operations from a delivery shelf to a shipping box continuously, a stop positioning accuracy value is set individually for each axis for each operation. A stop positioning control method for a picking device, characterized in that stop position control of each axis for each operation is performed according to the setting contents. 2. In a picking device using an orthogonal three-axis manipulator, when a series of operation sequences from a delivery shelf to a shipping box are continuously executed, a stop positioning accuracy value is individually set for each axis for each operation. In the stop positioning control method of the picking device, which is registered in the memory table and the stop position control of each axis for each operation is performed according to this setting content, the stop positioning accuracy value on the memory table is orthogonal. A stop-positioning control method for a picking device, wherein the operation of the 3-axis manipulator reaching a position for handling a picking object is a rank in which the highest stop-positioning accuracy value is required, and a hierarchical structure is formed with this as a vertex. 3. In a picking apparatus using an orthogonal three-axis manipulator, when performing a series of operation sequences from a delivery shelf to a shipping box continuously, a stop positioning accuracy value is individually set for each axis for each operation. In the stop positioning control method of the picking device, which is registered in the memory table and the stop position control of each axis for each operation is performed according to this setting content, the position at which the orthogonal three-axis manipulator handles the picking target object. The motion reaching to is defined as the identifier of the rank for which the highest stop positioning accuracy value is required, and a hierarchical structure of the identifier-stop positioning accuracy value having this as a vertex is constructed, and at the beginning of each operation processing sequence, Initialize the identifier of each layer to be defined, and when executing each operation processing sequence,
A stop positioning control method for a picking device, characterized in that a positioning accuracy value is determined by looking at the leading identifier, and stop control of each axis for each operation is performed so as to reach the determined positioning accuracy value. 4. The picking apparatus stop / position control method according to claim 2, wherein the object gripping operation is set to the highest rank, and the operation in the shipping rack is set to the next rank according to the required range of each operation sequence. A stop-positioning control method for a picking device, characterized by assigning an identifier to each of the outermost operations as the lowest. 5. The stop positioning control of the picking device according to claim 1, wherein the stop positioning accuracy value is determined from a settling time of a vibration amplitude value of a mechanical system generated when each axis stops. Method. 6. In a picking apparatus using an orthogonal three-axis manipulator, when a series of operation sequences from a delivery shelf to a shipping box are continuously executed, a stop positioning accuracy value is individually set for each axis for each operation. In the position control method of the picking device, which is registered in the memory table and the stop position control of each axis for each operation is performed according to this setting content, in the position where the orthogonal three-axis manipulator handles the picking target object. The operation to reach is used as an identifier of the rank that requires the highest stop positioning accuracy value,
A hierarchical structure of identifier-stop positioning accuracy value having this as a vertex is constructed, and at the beginning of each operation processing sequence, the identifier of each hierarchy defined for each is initialized, and the sequence of each operation processing is executed. In this case, the position control method of the picking device is such that the movement control of each axis is performed according to the operation processing sequence, and at the time of stopping, the stop control is performed so that the positioning accuracy value is determined according to the identifier at the beginning of each operation sequence. 7. In a picking device using an orthogonal three-axis manipulator, when performing a series of operations from a delivery shelf to a shipping box in succession, the required stop positioning accuracy required for each axis is initially set for each operation. A stop positioning control device for a picking device, comprising: setting means for setting; and control means for controlling stop of each axis for each operation according to the contents of the setting. 8. In a picking device using an orthogonal three-axis manipulator, when performing a series of operation sequences from a delivery shelf to a shipping box continuously, a stop positioning accuracy value is individually set for each axis for each operation. The position where the orthogonal three-axis manipulator handles the picking target in the stop positioning control device of the picking device which is registered in the memory table and controls the stop position of each axis for each operation according to the setting contents. The motion that reaches the position is defined as an identifier of the rank for which the highest stop positioning accuracy value is required, and an identifier of a hierarchical structure having this as a vertex-stop positioning accuracy value. Initializing means for initializing hierarchy identifiers, and when executing each operation processing sequence, look at the beginning identifier A stop positioning control device for a picking device, comprising: stop control means for determining a positioning accuracy value, and performing stop control of each axis for each operation so that the determined positioning accuracy value is obtained. 9. The stop-positioning control device for a picking device according to claim 8, wherein the stop-positioning accuracy value is determined from a settling time of a vibration amplitude value of a mechanical system generated when each axis stops. 10. In a picking device using an orthogonal three-axis manipulator, when performing a series of operation sequences from a delivery shelf to a shipping box continuously, a stop positioning accuracy value is individually set for each axis for each operation. In the position control method of the picking device, which is registered in the memory table and the stop position control of each axis for each operation is performed according to this setting content, in the position where the orthogonal three-axis manipulator handles the picking target object. The operation to reach is used as an identifier of a rank for which the highest stop positioning accuracy value is required, and an identifier of a hierarchical structure having this as a vertex-stop positioning accuracy value, and each layer defined at the beginning of each operation processing sequence. The initial setting means for initially setting the identifier of Position control device for the picking device, which controls the movement of each axis and performs stop control at the time of stopping so that the positioning accuracy value is determined according to the identifier at the beginning of each operation sequence. . 11. The position control device for a picking device according to claim 9, wherein the stop positioning accuracy value is determined from a settling time of a vibration amplitude value of a mechanical system generated when each axis is stopped. 12. The position control device for a picking device according to claim 9, wherein the picking target is a floppy disk or a compact disk housed in a regular output shelf on the vertical axis. 13. A picking device having the control device of claim 9.