JPS6042123B2 - Mobile address detection device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a mobile object address detection device using a counting method.

Conventionally, the closest example to the present invention is a stacker crane address detection system in an automated warehouse.

In this system, a stacker crane 2 operates to store a load on a three-dimensional shelf 1 at a predetermined address or pull out a load from the address according to an operator's command.

The stacker crane 2 recognizes the destination address using two methods: an absolute address method that combines multiple detectors and gives each address a unique pattern, a relative address method that uses a dedicated detector for each address, and a reference point method. There is a counting method that counts and recognizes how many addresses have been passed. However, recently, due to the complexity of processing the detection piece, the absolute number field method is no longer used, and the relative number field method, which requires a large number of detectors, is no longer used, and the method is mainly performed using the force one count method. There is. In the counting method shown in the figures from Fig. 1 to Fig. 4, the detection strip group 5 installed on the floor corresponding to each shelf is detected by the detector group 4 installed on the stacker crane 2 from the origin 3. The address is recognized by counting the numbers.

The counting method and stacker crane position determination method are as follows. As the stacker crane 2 moves forward, the counting sensor 7 is operated by the counting detection piece 10. However, at this time, the counting sensor 9 installed further away than the counting sensor 7 does not operate yet. As you move further forward, each counting sensor 7
, 9 do not operate, and then only the counting sensor 9 operates. In order to prevent counting errors, the counting sensor 9 is always inserted after the counting sensor 7, and it is assumed that the count is up by one. However, if the counting sensor 9 malfunctions and the counting sensor 7 operates again after the counting sensor 7, or vice versa, an error signal is output as a count error. Counting up is performed using the above method, but if you want to stop after counting the number of counts up to the target address, a stop command is output by operating the stop command sensor 11 with the stop position detection piece 12 as shown in Fig. 3. do.

Thereafter, the position confirmation sensors 6 and 8 simultaneously adjust and control the counting detection piece 10 to a position where it can be detected. Therefore, each address always requires a counting detection piece 10 and a stop position detection piece 12. Furthermore, the number of detectors required is at least five, and when the number of shelves increases, a great deal of labor is required to adjust the position and install each detector and each of the five detection pieces. FIG. 4 shows a block diagram of this counting type control circuit, in which the outputs of various detectors are passed through an interface circuit 17 to a microcomputer 16, which is a logical operation device, and input after level conversion. The microcomputer 16 determines the order and combination of detection operations of each detector, performs counting, center detection, other calculations, etc., and outputs the results. The output enters the motor control circuit 19 via the output interface circuit 18, and the drive motor 20 for driving the crane is controlled. Here, if an abnormality occurs in the output circuit midway, it cannot be detected by conventional detectors, and even though the motor control circuit 19 has an abnormality and a forward rotation command is output, it will reverse and run out of control. Accidents often occurred. In view of the above problems, the present invention reduces the number of detectors conventionally used.

The purpose is to shorten the adjustment process and establish a detection method that makes it possible to confirm responses to output commands. An embodiment in which the present invention is applied to a stacker crane will be described with reference to FIGS. 5 to 11.

The arrangement of the detectors installed on the stacker crane is as follows:
As shown in the figure, the front detector PHl and the rear detector PH2 are arranged so as to operate simultaneously in a certain section by an address detection piece 15 provided on the floor corresponding to the shelf entrance.

FIG. 6 shows a time chart when the stacker crane starts from a position away from the address, catches the address detection piece 15, and passes. First, the front detector PHl detects the address detection piece 15 and operates. Subsequently, the rear detector PH2 operates, and then the front detector PHl and the rear detector P
0FF in order of H2. Under normal conditions, when driving forward, the detectors operate in the above order, and when driving backwards, the reverse detector PH2 operates first, and the front detector PH operates later.
The order is l. Further, the address is counted up and down when both the front detector PHl and the rear detector PH2 operate. As a method for detecting abnormalities, for example, when moving forward, the front detector PHl changes from 0FF state to 0.
The change to the N state is memorized, and as the rear detector PH2 similarly changes from the 0FF state to the 0N state, the front detector PH
A method of resetting the memory of l is adopted. Rear detector P
H2 does not work for some reason, and when the next address is reached, the previous detector PHl changes from the OFF state to the ON state again. If the stored front detector PHl is not reset at this time and remains as it is, an abnormality can be discovered because the signal from the rear detector PH2 has been overlooked. Detecting that the front detector PHl is not operating and the rear detector PH2 detects this is done in the same way as when the vehicle is traveling backwards. If an abnormality in the direction of movement is detected, for example, when driving forward, the front detector P
This method is based on the method of confirming that the post-detector PH2 is in the ON state when Hl changes from the ON state to the 0FF state.

It is clear from the time chart of FIG. 6 that there is an abnormality if the post-detector PH2 becomes ON at the time of this change. Counting up or down is performed when it is determined that both the front detector PHl and the rear detector PH2 have operated.

However, computers move very quickly and actually execute the same program many times per second, and the period during which both the front detector PH1 and the rear detector PH2 are running the same program is short. When both are working together, depending on how many times the program runs, the number of times the program runs will be counted extra. Therefore, at the first time when they operate together, they are counted up or down, the fact that they operated together is memorized, and the next time the program is run, the count-up is ignored. A method is adopted in which this memory is reset when one of them shifts to the OFF state, making it possible to perform the next count up or down. The control program for the stacker crane has a program structure as shown in FIG. 7. The program is started by a command from the push button 21, and an interrupt analysis task 22 analyzes what needs to be done from now on.

When the analysis is completed by activation by push button input, the interrupt analysis task 22 then activates the work information acquisition task 23 and the hard timer 24. In work information import task 23,
Read information such as what work is to be executed and what address the destination is. When the hard timer 24 is activated, it interrupts the program at regular intervals. As a result, the interrupt analysis task 22 starts the program from the beginning of the detector input task 25.
Once started, the hard timer 24 performs an interrupt operation at fixed time intervals until a stop command is received, so that the program can be run in short cycles. In the detector input task 25, current information of the front detector PHl, rear detector PH2, etc. is taken in. The count calculation task 26 is the detector input task 25
It is started when the is finished.

The processing here includes checking for an abnormal condition when counting up or down, checking the direction of operation, and counting up or down. When the processing in the count calculation task 26 is completed, a traveling operation task 27 is activated to operate the actual stacker crane, and here outputs operating direction commands, speed commands, etc. to the control circuit of the stacker crane, and operates the stacker crane.

When a count error, an abnormality in the traveling direction, etc. is discovered, the emergency stop task 28 is activated, and the crane is brought to an emergency stop by reducing all output to zero. The actual hardware configuration is shown in FIG.

CPU3 through P■/0 (process input/output device) 29
Input to O or output from CPU 3O is performed.
Further, temporary storage is stored in a RAM (volatile memory) 31, and items that do not change, such as programs, are stored in a ROM (non-volatile memory) 32. The CPU 3O understands the program contents, performs calculations and judgments, and outputs the results. Table 1 is a list of names of information to be temporarily stored.

Figures 9, 10, and 11 are detailed flowcharts of the above-mentioned "checking for abnormalities when counting up or down, and checking the running direction." As shown in the table.In the flowcharts of FIGS. 9, 10, and 11, the count error discovery process will first be described.

Block No. The determination unit 5 subtracts the current information table of the previous detector PHl and the previous information table of the previous detector PHl.

The current information table stores newly read detector information when the program is restarted by a timer interrupt. The previous information table stores information from before this program was restarted. If the result of subtraction is zero, it means that the current information is the same as the last time, and each detector PHl, PH2 has not changed at all, so no special processing is performed and block No. Proceed to step 35. If the result is greater than zero, that is, if the detector detects the address detection piece 15 and the signal rises to ゜゜1゛, block NO. Branches into IO. Block No. In lO, PH
It is determined whether the l storage table flag is 4"1゛1. The pre-detector PHL storage table flag is set when the judgment result in block No. 5 branches at ゜゜1゛. Also, the reset is done by the rear detector PH.
2 is performed when the storage table flag is set. That is, each of the detectors PHl and PH2 always operates after the front detector PHl operates as described above, and then the rear detector PH2 operates.
Since the rear detector PH2 is arranged to operate,
By setting the memory table flag, the previous detector PH
lReset the storage table flag. Now, if the detector signal of the rear detector PH2 does not come in due to some failure, the previous memory table is set to zero when the detector of the front detector PHl turns OFF. After that, the front detector PHL again
When it operates, the button No. In the judgment of 5, again ゜“1
" is output, and block No. Branches into IO. Block No. In the determination of lO, the storage table flag of the rear detector PH2 is not set, so the storage table flag of the front detector PH1 is not reset. For this reason, block No. Branches to emergency stop processing of 2OO. In this way, it is possible to discover an error in the detection of the rear detector PH2 or the failure of the front detector PH1 to enter twice in succession. Rear detector PH2
This is done in the same way. Next, check the direction of movement.Block No. 5, the previous detector P
If the result of subtracting the previous information table of the previous detector PHl from the current information table of Hl is smaller than zero, that is, if the previous detector PHl changes from 0N to 0FF, block NO.
．． It branches to 25.

The front detector PHl operates faster than the rear detector PH2 in the case of forward movement, and the front detector PHl turns 0FF while the rear detector PH2 is operating. Therefore block no.2
In the judgment of block No. 5, when the front detector PHl turns OFF, the motion direction command is judged, and if it is forward, block No. Branches into 3O. In block NO3O, the previous information table of the post-detector PH2 is referred to, and if it is “゜1
If so, it means that the vehicle is moving forward as described above. However, if it is set to ゜゜0゛, then the rear detector PH2 will be 0 first.
It means that it went FF, and despite the forward command,
The direction of movement is determined to be backward, and block No. Branches to emergency stop processing of 2OO. Also block no. 25, when it is determined that it is a backward command, block No. 35 and check the backward direction using the rear detector PH2. In this way, the direction of movement can be confirmed. The same applies to the determination of retreat. In block No. 35, in order to always update the information, the newly fetched current information is transferred to the previous information table.

Block No. 4O to 70 relate to the rear detector PH2 and are similar to those described above. Next, count up and count down will be explained.

In block NO75, the front detector PHL and the rear detector PH
2 are operating together. Counting up and down are performed at the rising edge of the signal when both detectors PHl and PH2 operate. Block No. If the result of the determination in step 75 is ゜“1,” block No. 8O determines whether the count storage table flag cassette is set.The count storage table flag indicates that both the front detector PHl and the rear detector PH2 operate Each detector PHl, PH2 in block NO8O is set at the very beginning.
Both are used to determine whether the "゜1" signal is the first one or the one when the subsequent program is restarted.If the count storage table flag is not set, block NO. Branch to 85. Block No. 85
Then, determine the direction of movement, and if it is forward movement, block No.
9O, if backward, block No. Branch to 95.
Counting always recognizes the same shelf as the same address, so it counts up when moving forward and counts down when moving backward. Block No. Since 9O is a forward movement, the address count table value ゜"1" is added to count up.For backward movement, a subtraction is performed at block No. 95. When blocks No. 9O and 95 are processed, block No. .lOO and sets the count memory table, and when the program is restarted and the processing proceeds to block No. 80 again, it is prevented from proceeding to block No. 85 or later and performing counting processing by mistake.Count Memory table is set and block No.80
If the process proceeds to , the process branches to the set side and no counting process is performed. The count memory table is reset using the previous detector PHL.
Alternatively, it is performed when either of the post-detectors PH2 is turned off. That is, the front detector PHl or the rear detector PH
2 is 0FF, the block No. In the judgment of 75, block No. Branches towards lO5 and blocks NO. Perform reset processing at lO5. Count processing is performed in this way. If an abnormality is discovered during the above processing, the process branches to emergency stop processing as described above.

The emergency stop process is not particularly relevant to the present invention, but to explain one example, the process of stopping the crane by setting all the microcomputer outputs to zero is performed, and the process of decoding and displaying the details of the abnormality is also performed. Furthermore, the stopping accuracy can be easily detected by checking the previous detector PH1 previous information table and the later detector PH2 previous information table which have been operating for a certain period of time or more.

As described above, according to the present invention, the signal from the same detector can be used as a reference signal for making multiple determinations, and the response operation to a command can be confirmed, so the number of detectors can be reduced. This also has the effect of improving the safety of moving objects.

[Brief explanation of drawings]

) Figure 1 is an internal elevation view of an automated warehouse, Figure 2 is an elevation view of a conventional detector arrangement, Figure 3 is a plan view of a conventional detector arrangement, and Figure 4 is a conventional stacker crane control. A block diagram of the circuit, FIG. 5 is a plan view of the detector arrangement according to the present invention, FIG. 6 is a time chart of the detection operation in the case of the detector arrangement according to the present invention, and FIG. 7 is a program in an embodiment of the present invention. FIG. 8 is a schematic diagram of a computer-related hardware configuration in an embodiment of the present invention, and FIGS. 9, 10, and 11 are program flowcharts employed in an embodiment of the present invention. PHl... Front detector, PH2... Back detector, 15... Address detection piece.

Claims (1)

[Scope of Claims] 1. A mobile body that is provided with a detector that moves along an address, detects a detection piece corresponding to the address by the detector, and uses the detection result to detect the address of the mobile body. In the address detection device, one detection piece is provided corresponding to each address, and two detectors are arranged on the moving body at an interval such that the one detection piece can be detected simultaneously in the moving direction of the moving body, An address detection device for a moving object, characterized in that it is provided with the following means (a) to (c) for operating by inputting state signals of the two detectors. (a) Normality/abnormality determination means for determining whether the direction of motion is normal or abnormal if the detector placed on the traveling side of the two detectors detects the detection piece first, and the direction of motion is determined to be normal if it is not. . (b) Memorize that the detector placed on the traveling side of the two detectors has detected the detection piece, and the other one of the two detectors detect the detection piece. When the detector placed on the running side detects the detection piece at the next address, it is considered abnormal if the detection state at the previous address has not been reset, and if it has been reset, the memory is reset. Detector operation determination means that determines that the detector is operating normally. (c) Address detection means that detects an address by counting in a state in which the above two determination means determine that the detection piece is normal and both of the two detectors detect the detection piece.