JP2008285271A - Article transport device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an article transport device capable of restricting vibration of a long-size soft body even in the case wherein a disturbance to the travelling control of a travelling body and a change of the long-size soft body during the travelling operation of the travelling body occur, and easy to structure a control means. <P>SOLUTION: In this article transport device, a control means 27 is constituted to control travelling of a travelling body with the feed-forward control to restrict vibration of a long-size soft body by generating a vibration control travelling speed pattern for restricting vibration and by operating a travelling driving means HD based on the vibration control travelling speed pattern, and with the feed-back control to restrict vibration of a long-size soft body by correcting the vibration control travelling speed pattern based on the detection information of an action detecting means S during travelling of the travelling body and by operating the travelling driving means based on the corrected vibration control travelling speed pattern. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention includes a traveling body for conveying an article that travels along the traveling path by the operation of a traveling drive means, a long flexible body for supporting an article that is mounted on the traveling body in a suspended state or a standing state, An article conveying apparatus provided with control means for controlling the traveling of the traveling body by operating the traveling driving means based on the traveling speed pattern in order to cause the traveling body to travel in a set traveling speed pattern About.

  The above-described article transporting apparatus is, for example, a long article supporting article such as a stacker crane in which an elevating mast (long flexible body) that supports an article so as to be movable up and down is installed in a standing state on a traveling carriage (running body). In order to transfer the article supported by the flexible body to the transfer target location, the travel body is traveled to the target travel position corresponding to the transfer target location, and the travel of the travel body is stopped. In order to transfer the article to the transfer target location immediately after the traveling of the traveling body is stopped, when the traveling body stops, the long flexible body for supporting the article is It is desirable not to shake.

  As a conventional example of the article conveying apparatus, the control means generates a vibration suppression travel speed pattern for suppressing vibrations so as to suppress vibration of the long flexible body, and travel drive means based on the vibration suppression travel speed pattern. There is one configured to control the traveling of the traveling body only by feedforward control that activates (see, for example, Non-Patent Document 1).

Proceedings of the 6th SICE System Integration Division Annual Conference (SI2005) p. 7-p. 8

  However, in the conventional configuration, the traveling of the traveling body is controlled only by feedforward control that operates the traveling driving means based on the vibration suppression traveling speed pattern for suppressing vibrations. And the influence of the mechanical system such as the backlash of the drive system cannot be dealt with. If a disturbance occurs when the traveling body is driven, the vibration of the long flexible body is excited by the disturbance. There is a case.

  Therefore, with the conventional configuration, when a disturbance occurs during the operation of the traveling body, the vibration of the long flexible body is excited by the influence of the disturbance, or the vibration is easily excited, and the traveling body becomes Even after stopping, the inconvenience that the vibration of the long flexible body continues for a long time is likely to occur.

  In addition, as in the past, when trying to suppress the vibration of the long flexible body during the running operation of the traveling body only by the feedforward control based on the vibration suppression traveling speed pattern for vibration suppression, the dynamic characteristics of the long flexible body are reduced. It is necessary to generate a corresponding vibration suppression travel speed pattern, but if the dynamic characteristic of the long flexible body changes due to the change of the support state of the article supported by the long flexible body for article support, The vibration suppression travel speed pattern does not correspond to the dynamic characteristics of the long flexible body, and even if the travel operation of the travel body is controlled with such a vibration suppression travel speed pattern, the vibration of the long flexible body Inconvenience that it cannot be suppressed occurs.

  Furthermore, in order to obtain the damping effect on the vibration of the long flexible body, it is necessary to generate a vibration suppression traveling speed pattern corresponding to the dynamic characteristics of the long flexible body, and the control means generates the vibration suppression traveling speed pattern. The control parameters required for this must correspond to some extent to the dynamic characteristics of the long flexible body. Therefore, it is necessary to set appropriate control parameters corresponding to the dynamic characteristics of the long flexible body to some extent at the design and manufacturing stage of the apparatus, and it is difficult to configure the control means.

  The present invention has been made in view of the above circumstances, and its purpose is that a disturbance to the traveling control of the traveling body and a change in the dynamic characteristics of the long flexible body occur during the traveling operation of the traveling body. Even if it exists, it exists in the point which can suppress the vibration of a long flexible body, and provides the goods conveyance apparatus which is easy to comprise a control means.

In order to achieve this object, an article conveying apparatus according to the present invention includes:
A traveling body for conveying articles that travels along the travel path by the operation of the travel drive means;
A long flexible body for article support equipped in a suspended or standing state on the traveling body;
Control means for controlling the traveling of the traveling body by operating the traveling driving means based on the traveling speed pattern in order to cause the traveling body to travel in a set traveling speed pattern. The first characteristic configuration is
A behavior detecting means for detecting the behavior of the long flexible body is provided;
Feed-forward control in which the control means generates a vibration suppression travel speed pattern for suppressing vibrations and operates the travel drive means based on the vibration suppression travel speed pattern in order to suppress vibration of the long flexible body. And, based on the detection information of the behavior detecting means during the travel of the traveling body, the vibration suppression travel speed pattern is corrected, and the travel drive means is operated based on the corrected vibration suppression travel speed pattern. In the point which is comprised so that driving | running | working of the said traveling body may be controlled by feedback control to be carried out.

  That is, the behavior detecting means detects the behavior of the long flexible body, and the control means generates a vibration suppression travel speed pattern for suppressing vibrations in order to suppress the vibration of the long flexible body. Based on the feedforward control that activates the travel drive means based on the travel speed pattern and the detection information of the behavior detection means during traveling of the traveling body, the vibration suppression travel speed pattern is corrected, and this corrected vibration suppression travel The traveling of the traveling body is controlled by both control methods including feedback control for operating the traveling drive means based on the speed pattern.

Therefore, in order to suppress the vibration of the long flexible body, the traveling body is controlled when the traveling of the traveling body is controlled by the feed forward control that operates the traveling drive means based on the vibration suppression traveling speed pattern for vibration suppression. Even if there is a disturbance due to slippage of the driving wheel or a change in the article support state and vibration of the long flexible body that cannot be suppressed by feedforward control may occur, the vibration of the long flexible body due to the generated vibration may occur. The behavior detection means detects the behavior, and based on the detection information, the control command indicated by the vibration suppression travel speed pattern is corrected to obtain a speed command that can suppress vibration caused by disturbance. be able to.

  Then, by commanding such a corrected control command to the traveling drive means, vibrations occurring in the long flexible body when the control command is commanded, including vibrations caused by disturbance, are suppressed. can do.

  Also, it occurs even when it becomes difficult to suppress vibration by feedforward control because the dynamic characteristics of the long flexible body changes due to the article support state of the long flexible body changing during the running operation of the traveling body The behavior detecting means detects the behavior of the long flexible body due to the vibration, and based on the detection information, the vibration suppression travel speed pattern can be corrected so as to suppress the vibration of the long flexible body.

  Therefore, by controlling the traveling of the traveling body with the corrected vibration suppression traveling speed pattern, the dynamic characteristics of the long flexible body change, and the feedforward control alone cannot sufficiently suppress the vibration of the long flexible body. Even in the state, the vibration of the long flexible body can be suppressed by feedback control.

  Furthermore, by performing both feedforward control and feedback control, even if the control parameters for the feedforward control in the control means do not strictly correspond to the dynamic characteristics of the long flexible body, the feedforward control is performed. Therefore, when the vibration of the long flexible body is not sufficiently suppressed during the traveling operation, the generated vibration can be suppressed by feedback control.

  Therefore, even if the control parameter for the feedforward control is not an appropriate control parameter corresponding to the dynamic characteristics of the long flexible body to some extent, vibration of the long flexible body can be suppressed during the traveling operation. The strictness required when setting the control parameter for the feedforward control in the design and manufacturing stage of the apparatus is relaxed, and the control means can be easily configured.

  As described above, according to the first characteristic configuration of the present invention, even when a disturbance to the traveling control of the traveling body or a change in dynamic characteristics of the long flexible body occurs during the traveling operation of the traveling body, the long flexible body The present invention has led to an article transporter that can suppress body vibration and that can easily constitute a control means.

  According to a second characteristic configuration of the article transporting apparatus according to the present invention, in the first characteristic configuration, the control unit performs the vibration suppression by using a notch filter having a natural frequency of the long flexible body as a removal band as feedforward control. It is in the point comprised so that a travel speed pattern may be produced | generated.

  In other words, as the feedforward control, the control means generates a vibration suppression travel speed pattern by a notch filter that uses the natural frequency of the long flexible body as a removal band, so the natural frequency of the long flexible body is grasped in advance. By designing a notch filter having a removal band corresponding to the natural frequency, vibration corresponding to the natural frequency of the long flexible body when the traveling body is operated can be suppressed.

  And since a notch filter can be comprised only by setting two parameters, a frequency and a damping ratio, the setting of the control parameter about feedforward control is easy.

  As described above, according to the second characteristic configuration of the present invention, an article conveying apparatus capable of suppressing vibration corresponding to the natural frequency of the long flexible body has been obtained by simple control parameter setting. .

  According to a third feature configuration of the article transporting apparatus according to the present invention, in the first or second feature configuration, detection information corresponding to an amount of deformation at the end portion of the long flexible body is detected at the end portion on the traveling body side. Is provided, and the control means is configured to correct the vibration suppression traveling speed pattern based on detection information of the strain gauge as the feedback control.

  That is, the strain gauge as the behavior detecting means outputs detection information corresponding to the deformation amount at the end portion of the long flexible body on the traveling body side, and the control means is based on the strain gauge detection information as feedback control. Since the traveling speed pattern is corrected, the control means can correct the traveling speed pattern in accordance with the amount of deformation at the end portion of the long flexible body on the traveling body side.

  In other words, the strain gauge detection information corresponds to the amount of deformation at the end portion on the traveling body side that is easily affected by the overall motion state of the long flexible body. By using this, not only the motion state of a specific part of the mechanical structure of a long flexible body, but also the behavior influenced by the overall motion state including vibration due to higher-order vibration modes of the long flexible body It can be detected by the sensor, and the control means can correct the traveling speed pattern so that the entire motion state of the long flexible body is in a state that does not excite vibration.

  In addition, if the behavior detection means is a single acceleration sensor, it can only detect the motion state of a specific part of the mechanical structure of the long flexible body, and the behavior detection means is arranged at the upper and lower ends of the long flexible body. If the behavior of the long flexible body is detected by the difference in the output of the optical sensor, when the long flexible body vibrates in the secondary mode, it is difficult to detect the vibration of the secondary mode. As in the invention, the behavior detection means is provided with a strain gauge that outputs detection information corresponding to the amount of deformation at the end portion at the end portion on the traveling body side of the long flexible body, thereby vibrating the secondary mode. The behavior of the long flexible body affected by the entire motion state due to the vibration of each mode included can be detected by one sensor.

  The end portion of the long flexible body on the traveling body side may be a portion located on the traveling body side from the intermediate portion of the long flexible body, and preferably the long flexible body from the end of the long flexible body on the traveling body side. A portion located on the traveling body side from a position separated by about 1/10 of the entire length of the body is preferable.

  In addition, since the strain gauge is provided at the end portion of the long flexible body on the traveling body side, compared with the case where the sensor is provided at the end of the long flexible body opposite to the traveling body, The connection distance can be made relatively short, and it is possible to improve the reliability as feedback information when suppressing the vibration of a long flexible body by feedback control by suppressing signal delay and reducing the influence of ambient noise. it can.

  Thus, according to the third characteristic configuration of the present invention, the long flexible body is configured such that the overall motion state of the long flexible body does not excite vibration by feedback control based on highly reliable feedback information. An article conveying apparatus capable of suppressing vibrations of the sheet has been obtained.

  Hereinafter, an embodiment of an article conveying device of the present invention will be described based on the drawings. In the present embodiment, as shown in FIG. 1, the article conveyance device is configured by a stacker crane 3 installed in an automatic warehouse facility SU provided with an article storage shelf 1.

  The article storage shelves 1 are installed at an interval so that the article loading / unloading directions face each other. Each article storage shelf 1 has a plurality of a pair of front and rear support columns 1a standing in the left-right direction, and each pair of front and rear support columns 1a has a mounting support portion 1b extending in the left-right direction spaced in the vertical direction. A plurality are provided apart. A pair of front and rear support columns 1a and a pair of left and right mounting support portions 1b form a single storage portion 4, and a plurality of the storage portions 4 are arranged side by side.

  A travel path 2 for the stacker crane 3 is formed between the article storage shelves 1. A travel rail 5 is installed on the floor side of the travel path 2, and a guide rail 6 is installed on the ceiling side along the longitudinal direction of the article storage shelf 1. On one end side of the traveling rail 5, a ground-side controller 7 that manages the operation of the stacker crane 3 and a pair of loading platforms 8 with the traveling rail 5 interposed therebetween are provided.

  The stacker crane 3 includes a traveling carriage 10 as a traveling body that can travel along the traveling path 2 on the traveling rail 5, and a pair of front and rear quadrangular prisms in the moving direction of the traveling carriage 10 erected on the traveling carriage 10. The lift masts 11a and 11b and a lift platform 12 that can be lifted and lowered along a lift path formed along the lift masts 11a and 11b are configured. Each of these elevating masts 11a and 11b corresponds to the long flexible body of the present invention, and the stacker crane 3 in the present embodiment vibrates the rear mast 11b of these elevating masts 11a and 11b. It is configured to suppress.

  The traveling carriage 10 is guided to travel on the ground-side travel rail 5 of the travel path 2, and the upper frame 15 connecting the upper ends of the lifting masts 11 a and 11 b is connected to the guide rail 6 on the ceiling side of the travel path 2. When the traveling carriage 10 self-travels in the guided state, it can be moved in the lateral direction of the storage shelf 1.

  When the configuration of the traveling carriage 10 is described, the traveling carriage 10 is provided with two front and rear wheels 23 that can travel on the traveling rail 5, and one of the two wheels 23 on one end side in the longitudinal direction of the vehicle body is provided. The driving wheel 23a for propulsion driven by the traveling servo motor M1 is configured, and the wheel on the other end side in the longitudinal direction of the vehicle body is configured as a freely driven wheel 23b.

  The traveling carriage 10 includes traveling servo amplifiers SA1 and traveling servomotors M1 as traveling drive means HD that rotationally drives the drive wheels 23a of the traveling carriage 10, and lift drive means VD that drives the lift 12 up and down. A lift servo amplifier SA2 and a lift servo motor M2 are provided. And the crane control apparatus 27 comprised using the general purpose microcomputer is provided so that various control information can be communicated with the ground side controller 7 with the infrared communication apparatus 28 (refer FIG. 3). As will be described in detail later, the crane control device 27 sets the travel speed value based on the motor rotation speed to the travel drive means HD and the lift drive means VD based on the transport command commanded by the ground controller 7. Command the lifting speed value by motor rotation speed.

  The traveling carriage 10 is provided with a traveling laser rangefinder 25 that projects laser light for distance measurement in the horizontal direction. In the vicinity of the end of the travel path 2 on the ground controller 7 side, a reflector 26 that reflects the laser light from the travel laser range finder 25 is provided. A distance detecting laser beam is projected toward the reflecting plate 26 to detect the distance to the reflecting plate 26.

  Further, the traveling carriage 10 has an elevation laser range finder 20 for projecting laser light for distance measurement in a substantially horizontal direction, and an optical path of the laser light projected from the elevation laser range finder 20 vertically upward. A mirror 22 is provided for bending and irradiating the reflecting plate 21 installed on the lower surface of the lifting platform 12. The laser beam reflected by the reflector 21 is further reflected by the mirror 22 and reaches the elevating laser rangefinder 20. The elevating laser rangefinder 20 is bent by the laser beam. The distance to the reflecting plate 21 along the optical path is detected.

  The lifting platform 12 is provided in a state of being supported suspended by a pair of lifting wires 14 wound around a winding drum 18. The pair of elevating wires 14 is forward in an advancing direction (hereinafter referred to as an advancing direction) when the upper sheave 16 provided on the upper frame 15 and the front mast 11a (the stacker crane 3 travels away from the ground controller 7). Is guided by an intermediate sheave 17 provided at the bottom of the mast. The lifting servo motor M2 rotationally drives the winding drum 18, so that the lifting platform 12 can be lifted by feeding and winding the pair of lifting wires 14.

  The lifting platform 12 has an article Q (specifically, a pallet P located at the bottom of the article Q, and a pallet P located at the bottom of the article Q) by moving the slide fork device 9 as an article holding unit back and forth. A transfer device 13 capable of transferring the load W) placed on the pallet P is provided.

  In addition to the slide fork mechanism 9 for placing and supporting the pallet P of the article Q, the transfer device 13 includes a fork servo amplifier SA3 and a fork servo as an exit / retreat drive means FD for driving the slide fork mechanism 9 to exit and retract. A motor M3 is provided.

  The distortion which outputs the detection information corresponding to the deformation | transformation amount in the lower end part of the back side mast 11b to the lower end part of the back side mast 11b of the back side in the advancing direction of the stacker crane 3 among a pair of raising / lowering masts 11a, 11b. A gauge S is provided.

  The lower end portion of the rear mast 11b where the strain gauge S is provided may be a portion located on the traveling carriage 10 side from the middle portion of the rear mast 11b, and preferably the traveling carriage 10 of the rear mast 11b. A portion located on the traveling carriage 10 side from a position higher by about 1/10 of the total length of the rear mast 11b from the end on the side is preferable.

  Since the strain gauge S detects an amount corresponding to the deformation amount at the lower end portion of the rear mast 11b, the bending moment generated at the lower end portion can be detected. Since the lower end of the rear mast 11b is connected to the traveling carriage 10, the bending moment generated at the lower end is the behavior of the entire mast including the vibration of each part of the mast due to the higher-order vibration mode of the rear mast 11b. The physical quantity corresponding to the entire behavior of the rear mast 11b can be detected by detecting the bending moment generated at the lower end. That is, the strain gauge S functions as a behavior detection unit that detects the behavior of the rear mast 11b.

  Although the strain gauge S is provided solely on the rear side surface of the rear mast 11b, a pair of strain gauges may be provided together with the front side surface of the rear mast 11b. In this case, the relationship between the actual deformation amount at the lower end portion of the rear mast 11b and the deformation amount detected as a bending moment by using the difference between the outputs of the respective strain gauges, for example, by incorporating them on the two sides of the bridge. The bending moment detected by the pair of strain gauges S becomes more appropriate as a physical quantity indicating the entire behavior of the rear mast 11b.

  The reason why the strain gauge S is provided not on the front mast 11a but on the rear mast 11b is to avoid the influence of unnecessary radiation of M1 and M2 as much as possible and to prevent noise from being mixed into the detection information of the strain gauge S. This is to avoid it. Further, by providing the strain gauge S at the lower end portion of the front mast 11a, the signal line to the crane control device 27 provided in the traveling carriage 10 is shortened to prevent noise mixing and signal delay. .

  As shown in FIG. 3, a traveling laser range finder 25 and an elevating laser range finder 20 are connected to the crane control device 27 provided in the traveling carriage 10. Further, a traveling servo motor M1 is connected via a traveling servo amplifier SA1, a lifting servo motor M2 is connected via a lifting servo amplifier SA2, and a fork servo motor M1 is connected via a fork servo amplifier SA3. ing.

  The travel servomotor M1, the lift servomotor M2, and the fork servomotor M3 are all synchronous AC motors equipped with an encoder. The traveling servo amplifier SA1 and the lifting servo amplifier SA2 control the rotation operation of the corresponding servo motor in the speed control mode. The fork servo amplifier SA3 controls the rotation operation of the corresponding servo motor according to the position control mode.

  That is, when the traveling servo amplifier SA1 operating in the speed control mode is instructed by the crane control device 27 to perform a traveling operation command based on the rotational speed of the traveling servomotor M1, the rotational speed of the traveling servomotor M1 is adjusted. Based on the rotational speed of the traveling servomotor M1 detected by the encoder included in the traveling servomotor M1 so as to be the rotational speed commanded by the traveling operation command, the motor driving current (torque) and its frequency ( Speed).

  Similarly, when the lifting / lowering servo amplifier SA2 operating in the speed control mode is instructed by the crane control device 27 to move up and down according to the rotation speed of the lifting / lowering servomotor M2, the rotation speed of the lifting / lowering servomotor M2 is increased or decreased. The motor driving current (torque) and its frequency (speed) based on the rotational speed of the lifting servomotor M2 detected by the encoder included in the lifting servomotor M2 so as to be the rotational speed commanded by the operation command. ) To control.

  Further, when the fork servo amplifier SA3 operating in the position control mode is instructed by the crane control device 27 to move in and out of the slide fork device 9, the rotation amount of the fork servo motor M3 is changed. Based on the amount of rotation of the fork servomotor M3 detected by the encoder included in the fork servomotor M3 so that the amount of rotation corresponds to the amount of exit and withdrawal commanded by the exit / exit operation command, the motor drive Current (torque) and its frequency (speed) are controlled.

  And the crane control apparatus 27 calculates | requires the distance from the driving | running | working origin position set near the edge part by the side of the ground side controller 7 of the driving | running route 2 based on the distance information which the driving laser rangefinder 25 detects, The traveling position of the traveling carriage 10 on the traveling path 2 is detected. Similarly, the crane control device 27 obtains the distance from the lift origin position set near the lower end of the lift path based on the distance information detected by the lift laser range finder 20, and in the lift path 2 It is comprised so that the raising / lowering position of the raising / lowering body 12 may be detected.

  With the above configuration, the crane control device 27 operates the traveling carriage 10 and the lifting platform 12 so as to position the transfer device 13 at the transfer stop position with respect to the loading table 8 or the storage unit 4 to be transferred. After moving the transfer device 13 to the transfer stop position, the slide is performed to transfer the article Q between the storage unit 4 or the loading table 8 and the transfer device 13. The fork device 9 is configured to control the exit / retreat operation of the fork device 9 and the lifting / lowering operation of the lifting platform 12.

  The crane control device 27 controls the stacker crane 3 as described above based on a control command from the ground-side controller 7. Specifically, the ground-side controller 7 sends a transport command including information specifying the loading table 8 or the storage unit 4 to be transferred to the crane control device 27 via the infrared communication device 28. Command.

  When the crane control device 27 receives the transport command, the crane control device 27 moves to a travel position (hereinafter referred to as a target travel position) corresponding to the transfer stop position for the loading table 8 or the storage unit 4 specified by the transport command. This is a time change of the rotational speed of the traveling servomotor M1 based on the required traveling distance from the traveling position of the traveling carriage 10 of the stacker crane 3 in the standby state to the target traveling position in order to position the mounting device 13. A traveling rotational speed pattern (corresponding to the traveling speed pattern of the present invention) is generated.

  In addition, when the crane control device 27 receives the transport command, the crane control device 27 moves up and down (hereinafter referred to as a target lift position) corresponding to the loading stop position for the loading table 8 or the storage unit 4 specified by the transport command. In order to position the transfer device 13 on the basis of the required lifting distance from the lifting position of the lifting platform 12 of the stacker crane 3 in the standby state to the target lifting position, the time change of the rotational speed of the lifting servo motor M2 The rotational speed pattern for raising and lowering is generated.

  Then, the crane control device 27 changes the vibration suppression rotational speed pattern (corresponding to the vibration suppression traveling speed pattern of the present invention) from the traveling rotational speed pattern to suppress the vibration of the elevating masts 11a and 11b. And generating a corrected vibration suppression rotation speed pattern by correcting the vibration suppression rotation speed pattern based on the detection information of the strain gauge S, and feedforward for operating the travel drive means HD based on the correction vibration suppression rotation speed pattern. The travel of the traveling carriage 10 of the stacker crane 3 is controlled by control and feedback control.

  Specifically, for each control cycle Th (in this embodiment, 10 [ms]), the rotational speed value indicated by the traveling rotational speed pattern is input to the digital notch filter, and the output of the digital notch filter is output. To obtain a vibration suppression rotation speed value corresponding to the vibration suppression rotation speed pattern, and output a corrected vibration suppression rotation speed value corrected based on the detection information of the strain gauge S to the traveling servo amplifier SA1. It is supposed to be.

  As described above, the crane control device 27 outputs the corrected vibration damping rotational speed value calculated as described above from the rotational speed value indicated by the traveling rotational speed pattern to the traveling servo amplifier SA1 at each control cycle Th. And the rotation speed value indicated by the rotation speed pattern for lifting is output to the lifting servo amplifier SA2.

  Next, of the control operations of the crane control device 27 when a conveyance command is instructed from the ground-side controller 7, the control operations for the traveling carriage 10 will be described based on the flowchart shown in FIG.

  First, in step # A1, the trapezoidal waveform is calculated from the distance from the current stop position on the travel route 2 detected based on the distance measurement information of the travel laser range finder 25 to the target travel position for the current transport command. A traveling rotational speed pattern is generated. The traveling rotational speed pattern is stored in a time series table data format as discrete values for each processing cycle Tc.

  In step # A2, prior to the start of traveling, a sample counter i that is incremented by 1 every processing cycle Tc after the start of traveling is initialized. Thereafter, until it is determined in step # A12 that the control mode switching condition is satisfied, the processes in steps # A3 to # A12 are repeatedly executed, and the traveling operation of the traveling carriage 10 is controlled by feedforward control and feedback control. .

First, the processing of step # A3 to step # A5 as feedforward control will be described. In step # A3, the rotational speed at time t = t _i corresponding to the value of the sample counter i with reference to the traveling rotational speed pattern is described. The value u (t _i ) is obtained and input to the digital notch filter in step # A4. In step # A5, a digital filter process is executed to calculate a filter output, and a vibration suppression rotation speed value y (t _i ) is obtained.

  The digital notch filter has an overshoot of the output waveform when the center frequency of the removal band corresponding to the natural frequency of the lifting masts 11a and 11b of the stacker crane 3 and the trapezoidal waveform of the traveling rotational speed pattern are input. This is a digital filter in which a notch filter specified by an attenuation ratio that does not occur as much as possible is discretized at a processing cycle Tc.

As described above, the crane control device 27 sequentially generates the vibration suppression rotational speed value y (t _i ) corresponding to the rotational speed value at each time indicated by the traveling rotational speed pattern for each control cycle Th. It is configured to generate a vibration suppression traveling speed pattern by a notch filter.

Next, the processing of step # A6 to step # A8 as feedback control will be described. In step # A6, a detection signal of the strain gauge S is acquired, and in step # A7, high-frequency noise is cut by a low-pass filter. The bending moment generated at the lower end of the rear mast 11b is acquired. Then, in step # A8, negative feedback is performed to add or subtract the value obtained by multiplying the output of the low-pass filter by a predetermined feedback gain to the damping rotational speed value y (t _i ) so as to reduce the absolute value of the bending moment. Te to calculate the damping speed value y (t _i) the speed increase correction or reduction correction to fix the damping speed values yfb (t _i).

In step # A9, after waiting for the timer interruption of the control cycle Th and when the control output timing comes, the process proceeds to step # A10, and the corrected vibration damping rotational speed value yfb (t _i ) for the traveling servo amplifier SA1. Is output.

  As described above, the crane control device 27 sets the vibration suppression traveling speed pattern to suppress the vibration of the lifting masts 11a and 11b based on the detection information of the strain gauge S as the behavior detecting means during traveling of the traveling carriage 10. Correction is made to perform feedback control for operating the travel drive means HD based on the corrected vibration damping travel speed pattern thus corrected.

In step # A11, the sample counter i is incremented. As a result, the rotational speed value u (t _{i + 1} ) for time t = t _{i + 1} can be acquired in step # A3 of the next processing cycle.

In step # A12, the corrected vibration suppression rotational speed value yfb (t _i ) is output to the traveling servo amplifier SA1 operating in the speed control mode to control the traveling operation of the traveling carriage 10 from the speed command mode. A creep rotation speed value yc corresponding to the creep speed of the traveling carriage 10 is continuously output to the traveling servo amplifier SA1 operating in the mode until the traveling carriage 10 is positioned at the target traveling position. It is determined whether or not a control mode switching condition for switching to the positioning mode for controlling the traveling operation is established.

Specifically, the crane control device 27 determines whether the traveling carriage 10 has exceeded the creep start position set a short distance from the target traveling position based on the distance measurement information of the traveling laser rangefinder 25, or Either the corrected vibration damping rotational speed value yfb (t _i ) continues below the set minimum speed (in this embodiment, the same value as the creep rotational speed value yc) continues for the set time or longer. If the above condition is satisfied, it is determined that the control mode switching condition is satisfied, and the process proceeds to the positioning control of step # A13 to enter the positioning mode. Until the control mode switching condition is satisfied, the process proceeds to step # A3 and the speed command mode is maintained.

  Positioning control after the control mode is switched to the positioning mode in step # A12 will be briefly described based on the flowchart shown in FIG. As shown in FIG. 5, the crane control device 27 repeats the processing of Step # B1 and Step # B2 until the traveling carriage 10 is located at the target traveling position, and the creep rotation speed corresponding to the creep speed of the traveling carriage 10. The value yc is output continuously. When the traveling vehicle 10 is located at the target traveling position, the loop of Step # B1 and Step # B2 is exited, and the process proceeds to Step # B3, where speed zero is output instead of the creep rotation speed value yc, and the traveling vehicle 10 travels. Stop operation.

As described above, the crane control device 27 inputs the rotational speed value u (t _i ) indicated by the traveling rotational speed pattern to the notch filter, and uses the vibration suppression rotational speed value y (t _i ) as the feedforward control value. And the corrected damping speed value yfb (t _i ) as a feedback control value is calculated by correcting the damping speed value y (t _i ) with the bending moment obtained from the detection signal of the strain gauge S. Then, the corrected vibration suppression rotational speed value yfb (t _i ) is output to the traveling servo amplifier SA1 to control the traveling operation of the traveling carriage 10. Therefore, during the traveling operation of the traveling carriage 10, a disturbance to the traveling control of the traveling carriage 10 due to slip of the driving wheel 23a, a change in the dynamic characteristics of the lifting masts 11a and 11b due to the lifting action of the lifting platform 12, etc. Even if it is a case, vibration of raising / lowering mast 11a, 11b can be suppressed.

  Moreover, since the traveling operation of the traveling carriage 10 is controlled by two-degree-of-freedom control of feedforward control and feedback control in order to suppress the vibration of the elevating masts 11a and 11b, the center frequency and attenuation ratio of the removal band of the notch filter are controlled. Even if the control parameters for the feedforward control are not strictly set, vibration that cannot be suppressed by the feedforward control can be suppressed by the feedback control. Therefore, since the control parameter can be set to some extent, the crane control device 27 can be easily configured.

[Another embodiment]
Hereinafter, other embodiments are listed.

(1) In the above-described embodiment, the article conveying apparatus is exemplified by the traveling body provided with the long flexible body in the standing state. However, the article conveying apparatus is not limited thereto, and the article conveying apparatus is suspended from the traveling body. For example, as an article conveying apparatus, a lifting body supported by a lifting mast mounted in a suspended state on a traveling body, or a traveling body, The lifting body may be supported so as to be movable up and down by a cord-like body mounted in a suspended state.

(2) In the above-described embodiment, the traveling carriage 10 as the traveling body is provided with the driving wheel 23a on one end side in the longitudinal direction of the vehicle body and the driven wheel 23b on the other end side in the longitudinal direction of the vehicle body. The above is illustrated as being configured to be able to travel on the upper side, but is not limited thereto, and for example, a pair of left and right drive wheels are provided on both ends in the longitudinal direction of the vehicle body, and configured to be able to travel on a pair of traveling rails. The traveling carriage 10 may be configured by a four-wheel drive system, and the specific configuration of the traveling carriage 10 as a traveling body can be changed as appropriate.

(3) In the above-described embodiment, the behavior detecting unit is configured by the strain gauge S. However, the present invention is not limited to this. For example, the displacement information, the speed information of the tip of the front mast 11a or the rear mast 11b, Alternatively, the behavior detection unit may be configured using a laser displacement meter, an acceleration sensor, or the like to detect acceleration information, and the specific configuration of the behavior detection unit can be changed as appropriate.

(4) In the above embodiment, the travel drive means is exemplified by the travel servo amplifier SA1 and the servo motor M1. However, the present invention is not limited to this. For example, the travel drive means is configured by an inverter and an AC motor. Alternatively, the specific configuration of the travel drive means can be changed as appropriate.

(5) In the above embodiment, the control means calculates the vibration suppression rotation speed value y (t _i ) for each control cycle Th, and the vibration suppression rotation speed pattern as the vibration suppression travel speed pattern is calculated by the travel of the stacker crane 3. An example is shown that is configured to be generated in real time during operation. However, the present invention is not limited to this. For example, vibration suppression travel speed patterns corresponding to all travel speed patterns are generated in advance and controlled based on the transport command. The vibration driving speed pattern may be selected, and the vibration suppression rotation speed value y (t _i ) indicated by the pattern may be output to the driving servo amplifier SA1. The timing for generating the swing traveling speed pattern can be changed as appropriate.

(6) In the said embodiment, although the control means illustrated what was comprised with the crane control apparatus 27 mounted in the stacker crane 3, it is not restricted to this, For example, the crane control apparatus 27 is installed in the ground side. The crane control device 27 may be configured to output the vibration suppression rotational speed value y (t _i ) to the traveling servo amplifier SA1 via an optical communication device or the like. Can be appropriately changed.

(7) In the above-described embodiment, the control unit exemplifies the feedback control in which the bending moment acquired from the detection information of the strain gauge S is used as the feedback signal in the feedback control. In feedback control, a configuration in which a shearing force acquired from detection information of the strain gauge S is used as a feedback signal, a laser displacement meter provided at an appropriate location (for example, the upper end portion) of the rear mast 11b, or It may be configured such that a displacement, speed, or acceleration at a predetermined position of the lifting mast acquired from the detection information of the acceleration sensor is used as a feedback signal, and the feedback signal in the feedback control can be changed as appropriate. .

(8) In the above-described embodiment, the control unit is exemplified as the feedforward control configured to generate the vibration suppression travel speed pattern by the notch filter. As feed-forward control, one configured to generate a vibration suppression travel speed pattern by an inverse system corresponding to the reverse characteristic of the vibration characteristics of a long flexible body, or to generate a vibration suppression travel speed pattern by input shaping technology It may be configured as follows.

(9) In the above-described embodiment, the traveling rotational speed pattern as the traveling speed pattern is exemplified as a trapezoidal waveform. However, the present invention is not limited to this. For example, the traveling rotational speed pattern has a linear acceleration from 0. Stands up, maintains the maximum acceleration for a certain time, and then linearly decreases from the maximum acceleration to 0. The waveform consists of an S-shaped curve obtained by integrating the speed pattern of the trapezoidal waveform with time. A waveform using a possible Gaussian curve may be used, and the specific configuration of the traveling rotational speed pattern can be changed as appropriate.

(10) In the above embodiment, the control unit is exemplified to be configured such that the control of the traveling operation of the traveling body is realized by software processing. It may be configured so that all or part of the control is realized by a hardware circuit.

The perspective view of the article storage facility provided with the article conveyance device of the present invention Front view of stacker crane Block diagram of control configuration of crane control device Flow chart of traveling control by crane control device Flow chart of positioning control by crane control device

Explanation of symbols

S strain gauge (behavior detection means)
HD travel drive means
u (t _i ) Travel speed pattern
y (t _i ) Vibration suppression travel speed pattern 2 Travel path 3 Article conveying device 10 Traveling bodies 11a and 11b Long flexible body 27 Control means

Claims (3)

A traveling body for conveying articles that travels along the travel path by the operation of the travel drive means;
A long flexible body for article support equipped in a suspended or standing state on the traveling body;
An article conveying apparatus provided with control means for controlling the traveling of the traveling body by operating the traveling driving means based on the traveling speed pattern in order to cause the traveling body to travel in a set traveling speed pattern Because
A behavior detecting means for detecting the behavior of the long flexible body is provided;
Feed-forward control in which the control means generates a vibration suppression travel speed pattern for suppressing vibrations and operates the travel drive means based on the vibration suppression travel speed pattern in order to suppress vibration of the long flexible body. And, based on the detection information of the behavior detecting means during the travel of the traveling body, the vibration suppression travel speed pattern is corrected, and the travel drive means is operated based on the corrected vibration suppression travel speed pattern. An article conveying apparatus configured to control the traveling of the traveling body by feedback control.   2. The article according to claim 1, wherein the control means is configured to generate the vibration suppression traveling speed pattern by a notch filter having a natural frequency of the long flexible body as a removal band as the feedforward control. Conveying device. As the behavior detection means, a strain gauge that outputs detection information corresponding to a deformation amount at the end portion is provided at the end portion on the traveling body side of the long flexible body,
The article conveying apparatus according to claim 1, wherein the control unit is configured to correct the vibration suppression travel speed pattern based on detection information of the strain gauge as the feedback control.

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