JP3237602B2 - Synchronous operation method and synchronous operation control method for crane group - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a crane tuning operation method and a tuning operation control method for simultaneously controlling the interference between cranes and the steadying control of a suspended load for a plurality of cranes traveling on the same traveling rail. About.

[0002]

2. Description of the Related Art In the case of transferring goods by a crane in a factory or a distribution terminal, the transfer work is often performed simultaneously by a plurality of cranes. At this time, it is necessary to perform interference control between a plurality of cranes, that is, control for preventing abnormal approaching and collision with other cranes. Therefore, several methods have been proposed for controlling interference or preventing collision between the plurality of cranes.

For example, Japanese Patent Laying-Open No. 2-215695 proposes a method of controlling the traveling speed by measuring the distance between adjacent cranes. In this method, each crane is provided with an approach distance measuring means for an adjacent crane and an arithmetic unit, and converts a change in the measured value of the approach distance into a relative approach speed. Then, the maximum allowable speed is calculated from the obtained relative approach speed, and the traveling speed of the crane is automatically reduced.

Japanese Patent Application Laid-Open No. Hei 7-16587 discloses a method for measuring a distance from an adjacent crane or a wall surface of a building.
A method using image processing has been proposed. In this method, a sign is installed on each crane, and an image of the sign is taken by an image pickup device from an adjacent crane or a wall surface of a building. Next, the number of pixels (dimensions) of the captured image of the sign is calculated and converted into the distance to the adjacent crane or the wall surface of the building. When the converted distance is smaller than a predetermined distance, the approach speed of the crane is reduced.

Japanese Patent Laid-Open Publication No. Hei 8-2879 proposes a method of setting a barrier in a traveling area of a crane using a computer for managing a warehouse to prevent another crane from entering. In this method, the management computer instructs a certain crane on a movement route, and after the crane starts moving, sets a barrier in a range separated by a predetermined interference prevention distance from the movement route. In this technique, an area inside the barrier is set as an interference prevention area, and other cranes are not instructed to move into the area until the crane finishes moving.

[0006]

In an automatic crane, an operation pattern is created on the basis of an acceleration / deceleration pattern corresponding to the swing cycle of a suspended load in order to control the suspension of the suspended load. By feeding back a measured value of the runout or the like to this operation pattern, a runout control for minimizing the runout is performed. Numerous techniques have been developed and widely known as the steady rest control method. However, these prior art steady rest controls are mainly applied to a single crane, and it is difficult to apply the steady rest control to the operation of a plurality of cranes.

[0007] In the techniques described in JP-A-2-215695 and JP-A-7-165387, there is no mention of the anti-sway control. In addition, in steady rest control, since the forward and backward movements of the crane are generally repeated within a short time, when the adjacent crane enters the steady rest operation, the distance and the relative approach speed of both cranes change in a short time. As a result, in these conventional techniques, when the relative approach speed or distance to the adjacent crane exceeds the limit,
There is a problem that the crane is stopped suddenly and the suspended load shakes greatly.

In the technique described in Japanese Patent Application Laid-Open No. H8-2879, acceleration and deceleration for steadying is performed during acceleration and deceleration. However, specifically, after actually stopping (the crane stops), the presence or absence of residual run-out is detected, and the crane is slightly moved by feedback control.
It is described that the operation of the steady rest and the fine adjustment of the stop position are performed. As described above, the steady rest control is not performed during the operation of the crane, but is performed separately from the operation of the crane. Therefore, it is expected that it takes a long time to stop the steady movement.

In this technique, since a barrier is set in a predetermined range from a certain crane and another crane is eliminated, it can be said that this method is reliable from the viewpoint of collision prevention. However, in the meantime, other cranes cannot enter the barrier, and the operation efficiency is reduced. In particular, when the barrier setting is fixed from the start of movement of a certain crane to the end of the movement, as in this technique, the size becomes unnecessarily large. This is because the range of the barrier includes the moving range of the crane, and there is a problem that the efficiency of the entire crane group is reduced.

[0010] Further, in this technique, a warehouse management computer manages the operation of a plurality of cranes. Therefore, the following problems caused by the centralized management of the operation of the crane group cannot be avoided.

In general, when centrally managing the operation of a plurality of cranes, the operation is as shown in FIG. Here, a higher-level ground control station that performs overall control of the entire crane group calculates an operation pattern for each crane. By using the result, an operation instruction planned so that the cranes do not collide with each other is transmitted to the on-board control station of each crane by ordinary ground-on-machine communication means.

However, in such a centralized management system, communication from the onboard control station to the ground control station is required to adjust the current position and operation timing of the cranes.
And communication from the ground control station to the onboard control station is required. As a result, real-time control becomes difficult due to delay due to communication. Therefore, the operation plan of the crane must be prepared on the assumption of the delay due to the communication, and it has been difficult to perform efficient synchronous operation control of the group of cranes.

[0013] The swing cycle of the suspended load changes every time the crane wire length changes due to operations such as lifting and lowering by the crane, so that the period as a pendulum element changes every moment. As a result, it is necessary to change the acceleration / deceleration pattern for the steady rest every moment. However, it is difficult to plan in advance all the crane routes, predict these operation patterns in detail, and determine the acceleration / deceleration patterns, since a huge amount of calculation is required.

The present invention solves the above-mentioned problems of the prior art, and can improve the operating rate of the entire crane group without lowering the operating efficiency of individual cranes by steadying control. It is another object of the present invention to provide a synchronous operation method and a synchronous operation control method for a group of cranes.

[0015]

According to a first aspect of the present invention, there is provided a crane group including a plurality of cranes traveling on the same traveling rail. Communicates with the adjacent crane and receives information on the operation pattern of the adjacent crane, and corrects its own operation pattern based on both the operation pattern of the adjacent crane and its own steady rest control. This is a synchronized operation method of a group of cranes that operate based on the operation pattern.

In the present invention, the traveling / stopping of the crane, the lifting / lowering of the suspended load, and the swing rest control of the suspended load are performed based on the operation pattern. In the initial state, that is, before the crane starts operating, the operation pattern is given from the host management system. After starting the operation, each crane continues to operate based on its operation pattern unless interference such as abnormal approach or collision with an adjacent crane is expected.

According to the present invention, when interference with an adjacent crane is expected, the interference is eliminated by changing its own operation pattern itself. A well-known method such as a change in the distance to an adjacent crane can be used to predict or determine the presence or absence of interference. The change of the operation pattern is performed based on the operation pattern of the adjacent crane located on the side of the traveling direction of the crane at that time. At this time, the operation pattern is changed on the premise of the steadying control. For example, a pattern that prioritizes the steadying control during acceleration / deceleration and an efficiency priority pattern during dynamic steady running.

The information on the operation pattern of the adjacent crane can be obtained by requesting and receiving the transmission of the information by communication with the adjacent crane. The information obtained from the adjacent crane is information on the operation pattern that the adjacent crane is planning at that time. Therefore, when the operation pattern of the adjacent crane is changed from the expected one, the own operation pattern is changed again. In this case, communication between adjacent cranes can be used.

Communication between adjacent cranes is basically performed periodically. When the communication amount is reduced, the information of the changed operation pattern may be transmitted when the operation pattern is changed, or the information may be transmitted when there is a transmission request by notifying the information to the adjacent crane. .

According to a second aspect of the present invention, for a crane group consisting of a plurality of cranes traveling on the same traveling rail and having communication means with a ground station, all cranes directly communicate with adjacent cranes. A direct communication means between adjacent cranes, an operation pattern correcting means for correcting the own operation pattern based on the constraints of both the operation pattern of the adjacent crane obtained by the direct communication means and the own steady rest control; Operation control means for controlling operation based on the operation pattern of
This is a synchronized operation control method for a group of cranes that synchronizes operation control between cranes in response to operation instructions for individual cranes instructed by communication from a ground station.

The present invention is an operation control system for realizing the first invention, in which information on operation patterns of adjacent cranes is obtained by means of direct communication between adjacent cranes, and the own operation pattern is obtained by operation pattern correction means. Fix it. Here, similarly to the first invention, the operation pattern correcting means corrects its own operation pattern based on both restrictions of the operation pattern of the adjacent crane and its own steadying control. The operation control means always controls the operation such as running, lifting and lowering the suspended load, based on its own operation pattern regardless of whether or not the correction is made.

According to the present invention, each crane is provided with the direct communication means and the operation pattern correction means, and corrects the operation instruction for each crane instructed by communication from the ground station, thereby preventing interference with an adjacent crane. At the same time, the suspension of the suspended load is controlled. As a result, the ground station only needs to give a basic operation instruction such as a moving place to each crane, and each crane handles detailed control such as interference prevention and steadying control.

As described above, according to the present invention, each crane exchanges data between cranes and processes the data.
A control method that performs operation control based on the result is used, and a synchronized operation of a group of cranes performed in synchronization with another crane can be realized. Further, in the present invention, since the synchronous operation is performed while constantly changing the operation pattern by the communication between the adjacent cranes, the distance control between the adjacent cranes,
It is not necessary to perform relative speed control or barrier setting. Therefore, problems caused by these can be solved.

[0024]

FIG. 1 is a flowchart showing an example of an embodiment of the present invention. First, in Step 1, the operation pattern of the own crane is compared with the operation pattern of the adjacent crane obtained by the communication between the adjacent cranes. The comparison is performed over a predetermined period of time with respect to the distance to an adjacent crane.

In the next step 2 using this comparison result, it is determined whether or not interference with an adjacent crane is expected. If no interference is expected, step 5
The operation pattern is changed to an operation pattern in which continuation or efficiency is prioritized as it is. If interference is expected, proceed to the next step 3.

In step 3, it is determined whether or not the steady rest pattern constituting the operation pattern can be changed. Here, the fact that the steady pattern can be changed means that the steady pattern can be changed so as to eliminate the interference. When the motion pattern does not include the steady rest pattern (for example, during steady running)
Is to determine whether the steady rest pattern can be adopted. If it is possible to change to another steady rest pattern, the steady rest pattern is changed in the next step 4.

If it is not possible to change the steadying pattern so as to eliminate the interference, in step 6, the operation pattern is changed to an operation pattern giving priority to avoiding interference. Basically, its own operation pattern is changed to an operation pattern similar to that of an adjacent crane located in the traveling direction. At this time, the anti-sway control is interrupted, but it is preferable to set the traveling speed and the like so as to depart from the interference range by giving priority to avoiding interference.

FIG. 2 is a block diagram of an operation control system for realizing the present invention. Information on the operation pattern of the adjacent crane 9 is obtained by the direct communication means 1 between adjacent cranes, and the operation pattern correction means 2 corrects its own operation pattern. Here, similarly to the first invention, the operation pattern correction means 2 corrects its own operation pattern based on both the operation pattern of the adjacent crane 9 and its own steadying control. The driving control means 3 always determines whether the vehicle is running,
It controls operation such as lifting and lowering suspended loads.

During the operation of the crane group, each crane 9
However, by using the direct communication means 1 and the operation pattern correction means 2 to correct the operation instruction for each crane instructed by communication from the ground station 5, interference with the adjacent crane 9 can be prevented, and Is performed. As a result, the ground station 5 only needs to give a basic operation instruction such as a moving place to each of the cranes 9, and detailed control such as interference prevention and steadying control is directly performed between adjacent cranes. We are dealing with it. As described above, according to the present invention, each crane 9 is
And (directly with the adjacent crane 9) to perform operation control, thereby realizing a control method for performing synchronous operation of the crane group.

Next, a case in which two adjacent cranes perform a moving operation of articles one after another by synchronized operation will be described.
This will be described with reference to FIG. In this figure, the adjacent crane located in the direction of transporting the load is referred to as a preceding crane, and the self is referred to as a trailing crane.

(1) First, when the following crane receives a series of operation commands from the upper ground station (upper system), the following data (operation pattern) is transmitted to the preceding crane before the following crane starts as one cycle operation. ) Is requested by direct communication means. Required information: traveling direction, acceleration / deceleration pattern, and future planned traveling pattern of the preceding crane

(2) The following crane subdivides the traveling pattern by providing a changing point in the traveling pattern of the following crane in accordance with the changing point of the traveling pattern of the preceding crane.

(3) When the traveling direction is the same and interference with the preceding crane is expected: The following crane receives the timing at which the preceding crane starts traveling by direct communication means, and a. If the trailing crane's steadying travel pattern catches up with the leading crane's travel pattern (catch up when the trailing crane travels based on that travel pattern), the trailing pattern is synchronized with the travel pattern, ignoring the steady rest. The traveling of the crane is started, or the traveling pattern of the following crane is started by changing to a traveling pattern of low speed and low acceleration that cannot catch up with the preceding crane. b. When the traveling crane is separated from the traveling pattern of the preceding crane, the traveling of the succeeding crane is started with a steady rest pattern irrelevant to the traveling pattern.

(4) When the traveling pattern of the preceding crane changes: The following crane receives the timing at which the traveling pattern of the preceding crane changes by direct communication means,
As for (3): a. If the trailing crane's steadying travel pattern catches up with the leading crane's travel pattern (catch up when the trailing crane travels based on that travel pattern), the trailing pattern is synchronized with the travel pattern, ignoring the steady rest. The traveling of the crane is started, or the traveling pattern of the following crane is started by changing to a traveling pattern of low speed and low acceleration that cannot catch up with the preceding crane. b. When the traveling crane is separated from the traveling pattern of the preceding crane, the traveling of the succeeding crane is started with a steady rest pattern irrelevant to the traveling pattern.

(5) When the preceding crane starts traveling in a direction to get out of the area where the interference is expected: the succeeding crane receives the timing at which the traveling pattern of the preceding crane changes by the direct communication means, and (3) As in: a. If the trailing crane's steadying travel pattern catches up with the leading crane's travel pattern (catch up when the trailing crane travels based on that travel pattern), the trailing pattern is synchronized with the travel pattern, ignoring the steady rest. The traveling of the crane is started, or the traveling pattern of the following crane is started by changing to a traveling pattern of low speed and low acceleration that cannot catch up with the preceding crane. b. When the traveling crane is separated from the traveling pattern of the preceding crane, the traveling of the succeeding crane is started with a steady rest pattern irrelevant to the traveling pattern.

[0036]

According to the present invention, since the synchronous operation is performed while constantly changing the operation pattern by the communication between the adjacent cranes, it is not necessary to perform the distance control, the relative speed control, and the barrier setting between the adjacent cranes. . Therefore, the running efficiency of each crane does not decrease by individually performing the control and the steadying control, and the operating rate of the entire crane group can be improved.

[Brief description of the drawings]

FIG. 1 is a flowchart showing an example of an embodiment.

FIG. 2 is a block diagram illustrating an example of an operation control method.

FIG. 3 is a timing chart showing an example of the embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Direct communication means between adjacent cranes 2 Operation pattern correction means 3 Operation control means 4 Communication means 5 Ground station 9 Crane

Continuation of front page (58) Field surveyed (Int.Cl. ⁷ , DB name) B66C 13 / 22,15 / 04

Claims (2)

(57) [Claims] 1. A crane group comprising a plurality of cranes traveling on the same traveling rail, all the cranes operate based on their operation patterns and communicate with an adjacent crane in the traveling direction to communicate with the adjacent crane. Crane group that receives the information of the operation pattern of the crane, corrects its own operation pattern based on the constraints of both the operation pattern of the adjacent crane and its own steadying control, and then operates based on this corrected operation pattern Tuning operation method. 2. A crane group comprising a plurality of cranes traveling on the same traveling rail and having communication means with a ground station, wherein all cranes communicate directly with adjacent cranes. Direct communication between
Operation pattern correction means for correcting its own operation pattern based on the constraints of both the operation pattern of the adjacent crane obtained by this direct communication means and its own steady rest control,
Operation control means for controlling the operation based on its own operation pattern, so that the operation control is performed between the cranes in synchronization with the operation instructions for the individual cranes instructed by communication from the ground station. Synchronous operation control method for cranes.