JP2780013B2 - Traveling control method for moving objects - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a traveling control method for a moving body such as a stacker crane.

[0002]

2. Description of the Related Art As a traveling control method for a moving body of this type, a speed pattern is determined based on a difference between a current position and a target position of the moving body, and the moving body is caused to travel so as to match the speed pattern. Usually, a method of stopping a moving body at a target position is used.

FIG. 6 is a diagram showing a traveling speed pattern in the above-mentioned conventional traveling control method for a moving body. As illustrated, the acceleration running until provides certain speed range of the high-speed V _H, if the current position of the moving body away from a distance object position OP from position RP1 reaches a speed V _H mobile large acceleration When the vehicle reaches a high speed, the vehicle travels at a constant speed at the speed, and when the vehicle reaches a predetermined position P1, the high speed _VH is turned off and the low speed _VL is turned on. The vehicle is decelerated with a large deceleration, switched to the constant speed of the low speed _VL at the position PL1, braked at the control position PL2 a predetermined distance before the target position OP, and stopped at the target position OP. When the current position is closer to the target position OP than RP1 as in RP2 and RP3, the position P before the speed of the moving body reaches the high speed _VH is reached.
At 2, P3, the vehicle is switched to deceleration and the vehicle is decelerated.

[0004] However, when the travel is controlled by the travel pattern shown in FIG. 6, the current positions RP1, RP2, R
In the case of P3, since the high speed is turned off during acceleration, the machine is shaken, and the actual deceleration distance may become longer or overrun may occur. Therefore, in order to avoid this overrun, as shown in FIG. 7, traveling patterns A, B, C,... Providing a constant speed section CV during switching from acceleration to deceleration, regardless of the current position of the moving body. A traveling control method for producing a large number of traveling patterns and selecting a predetermined traveling pattern from the large number of traveling patterns A, B, C,. is there.

[0005]

However, the traveling control method shown in FIG. 7 prepares a number of traveling patterns, stores the traveling patterns and stores the traveling patterns in accordance with the current position of the traveling body. , A predetermined pattern is selected, and the traveling control of the moving body is performed based on the selected pattern. Therefore, it is necessary to store various types of traveling patterns, and to execute various types of traveling control (speed V _H ,
_{V H a, V H b,} V H c, control ...) is required, the travel control is becomes complicated.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a traveling control method for a moving body which can perform traveling control with a simple configuration by eliminating the above problems.

[0007]

SUMMARY OF THE INVENTION The present invention, which solves the above-mentioned problems, comprises: moving a moving body from a current position to a target position by accelerating at a first acceleration from a current position to a predetermined high speed; When the high speed is reached, the vehicle is caused to travel to the first switching position at a predetermined distance before the target position at the high speed constant speed, and is switched to deceleration traveling at the first deceleration at the first switching position. A traveling control method for a moving body that switches to low-speed traveling at a second switching position, travels at a constant low speed in the section from the second switching position to a target position, applies braking at a predetermined braking position, and stops at a target position. In the case where the current position causes the moving body to accelerate from the current position at the first acceleration and cannot reach the first switching position, a constant-speed traveling section at a predetermined high speed cannot be obtained, the current position and the target position From the difference Is calculated, a low acceleration / deceleration section is set based on the intermediate point position, the vehicle is accelerated at a first acceleration from the current position to the start point of the low acceleration / deceleration section, and the low acceleration / deceleration section is calculated. Is accelerated from the start point to the intermediate point at a second acceleration that is significantly smaller than the first acceleration, and decelerated from the intermediate point to the end point at a second deceleration that is significantly smaller than the first deceleration. The vehicle is decelerated at the first deceleration to the second switching position.

[0008]

As described above, according to the present invention, a high-speed constant-speed traveling section cannot be obtained until the current position accelerates the moving body from the current position at the first acceleration and reaches the first switching position. Calculating the intermediate point position from the difference between the current position and the target position, setting a low acceleration / deceleration section based on the intermediate point position, and accelerating at the first acceleration from the current position to the start point of the low acceleration / deceleration section In the low acceleration / deceleration section, the vehicle is accelerated from a start point to an intermediate point at a second acceleration significantly smaller than the first acceleration, and decelerated from an intermediate point to an end point at a second deceleration significantly smaller than the first deceleration. The vehicle is decelerated at the first deceleration from the end point of the low acceleration / deceleration section to the second switching position at a first deceleration, and further driven at a constant low speed from the second switching position to a braking position just before the target position. Stop at the target position Therefore, predetermined high speed, first acceleration, second acceleration, first deceleration, second deceleration, and low speed are set in advance, and the current position, the first switching position, the start point of the low acceleration / deceleration section, The traveling control can be performed by the acceleration deceleration and the braking in accordance with the intermediate point, the end point, the second switching position, and the braking position, so that the traveling control becomes extremely easy.

[0009]

FIG. 1 is a diagram for explaining a traveling control method of a moving object according to the present invention. If the current mobile is currently located RP1, the moving body accelerates traveling in the first acceleration a larger from the current position RP1, switched to a constant speed running of the high velocity V _H at position Pa reaching high speeds V _H, At the first switching position Pb, which is a predetermined distance before the target position OP, switching to deceleration traveling with a large first deceleration d is performed, and at the second switching position Pc, at a predetermined distance before the target position OP, switching to low speed _VL constant speed traveling. Then, braking is performed at a predetermined braking position Pd before the target position OP, and the moving body is stopped at the target position OP. Even when the current position of the moving body is apart from RP1, the same traveling control is performed only by changing the position Pa.

When the current position is located at RP2 closer to RP1, an intermediate point position M1 is calculated from the difference between the current position RP2 and the target position OP. The low acceleration / deceleration section La is set based on the calculated intermediate point position M1. Then, the moving body is accelerated at the first acceleration a from the current position RP2 to the start point Pes of the low acceleration / deceleration section La. In the low acceleration / deceleration section La, the vehicle is accelerated from the starting point Pes to the intermediate point position M1 with a small acceleration b significantly smaller than the first acceleration a, and the small acceleration significantly smaller than the first deceleration d from the intermediate point position M1 to the end point Pee. The vehicle is decelerated at the deceleration c and travels at a first deceleration d from the end point Pee to the second switching position Pc. At the second switching position Pc, the vehicle is switched to the constant traveling at the low speed _VL , and braking is performed at the braking position Pd to stop at the target position OP.

Similarly, in the case of the current position RP3, an intermediate point position M2 is calculated from the difference between the current position RP3 and the target position OP. A low acceleration / deceleration section La is set from the calculated intermediate point position M2, and the current position RP is also set in the case of the current position RP4.
The intermediate point position M3 is calculated from the difference between the position 4 and the target position OP. From the calculated intermediate point position M3 to the low acceleration / deceleration section L
Set a. Then, as described above, the moving body is caused to travel at the large acceleration a, the small acceleration b, the small deceleration c, and the first deceleration d, switched to the constant traveling at the low speed _VL at the second switching position Pc, and braked at the braking position Pd. To stop at the target position OP.

An example will be described in which the above-mentioned traveling control method for a moving body is used for traveling control of a stacker crane provided in an automatic warehouse. 2 and 3 are configuration diagrams of an automatic warehouse and a stacker crane. In FIG. 2, 1 is a stacker crane, and 2 is a shelf of an automatic warehouse. The stacker crane 1 includes a stacker crane main body 5 that travels along a shelf 2 guided by a traveling rail 3 and a ceiling rail 4, and a lifting platform 7 that is guided by a post 6 to move up and down. Is provided with a fork 8 for taking in and out articles stored in the shelves 2 on a pallet basis.

Reference numeral 15 denotes a driving motor for traveling.
Reference numeral 14 denotes a lifting drive motor. Reference numeral 16 denotes a control panel for controlling the operation of the stacker crane. The shelf 2 has a plurality of loading sections 13 in the traveling direction of the stacker crane 1 and the elevating table 7, and holds the articles 12 loaded on the pallet 11 by the pallet receiving table 9.

In the above-mentioned automatic warehouse, as shown in FIGS.
8 is installed by being pressed against the traveling rail 3 by a spring 17. The axis of the simulated wheel 18 has a pulse encoder 1
9 (see FIG. 4) are connected.

FIG. 4 is a block diagram showing the configuration of the control device. The control unit 20 includes a counter 20-1, a memory 20-2, an arithmetic processing unit 20-3, and an input / output unit 20-4.
A pulse encoder 19 connected to the shaft is connected, and a traveling drive unit 21, a lifting drive unit 22, and an input device 23 are connected to the input / output unit 20-4. Travel drive unit 21
Is provided with an inverter or the like and supplies driving power to the driving motor 15 for driving. The lifting drive unit 22 also includes an inverter and the like, and supplies driving power to the lifting drive motor 14. The control unit 20 is provided on the control panel 16 of the stacker crane 1.

The first acceleration a, the second acceleration b, the first deceleration d, and the second deceleration c shown in FIG. 1 can be set in accordance with the weight of the stacker crane 1 and the capacity characteristics of the traveling drive motor 15, and the like. The arithmetic expressions are stored in the memory 20-2. The first switching position, the second switching position Pc, and the braking position Pd can also be set if the target position OP, the high speed V _H , the low speed _VL, and the first deceleration d are determined. Is also stored in the memory 20-2. Further, the memory 20-2 has an arithmetic processing unit 2
Programs for executing various arithmetic processes and the like are stored in 0-3.

The operation of the control section 20 will be described based on the processing flow of the arithmetic processing section 20-3 shown in FIG. First, a target position OP is instructed (traveling forward or backward command) (step ST1), and a traveling high speed is commanded (step ST1).
2) The arithmetic processing unit 20-3 reads the count value of the counter 20-1 and confirms the current position of the stacker crane 1 (the counter 20-1 receives a signal from the pulse encoder 19 connected to the axis of the simulated wheel 18). Since the count value is incremented or decremented by counting the pulses, the count value indicates the current position (address).
T3).

[0018] Next, when the stacker crane from the current position to the acceleration running in the first acceleration a, velocity before reaching the first switch position Pb is determined whether reaching high speeds V _H (step ST4 If it reaches, a command signal is sent to the traveling drive unit via the input / output unit 20-4, and the stacker crane 1 is accelerated to the switching position Pa at the first acceleration a (step ST5). Subsequently stacker crane 1 travels at a constant speed of high-speed V _H (step ST
6) In the meantime, it is determined whether or not the first switching position Pb has been reached (step ST7). When the first switching position Pb has been reached, the process proceeds to step ST17 as will be described in detail later, and normal traveling control is performed. . Since the arithmetic expressions for calculating the first acceleration a and the first switching position Pb are stored in the memory 20-2, they are read out from the memory 20-2 and calculated by the arithmetic processing unit 20-3 to execute the above-mentioned travel control. Do.

[0019] In step ST4, if the speed V _H before reaching the first switch position Pb can not be obtained a predetermined interval, obtains the midpoint position M from the difference between the current position RP and the target position OP (Step ST8) Then, a low acceleration / deceleration section La is determined based on the intermediate point position M (step ST).
9). Then, the obtained intermediate point position M, the start point Pes and the end point Pee of the low acceleration / deceleration section La are stored in the memory 20-2. Next, a command signal is sent to the traveling drive unit 21 via the input / output unit 20-4, and the stacker crane 1 is moved to the first position.
The vehicle is accelerated at the acceleration a (step ST10). Subsequently, it is determined whether or not the stacker crane 1 has reached the start point Pes of the low acceleration / deceleration section La (step ST1).
1) If reached, stacker crane 1 at second acceleration b
Is accelerated (step ST12).

Subsequently, the stacker crane 1 is operated at a low acceleration.
It is determined whether or not the intermediate point position M of the deceleration section La has been reached (step ST13). If the intermediate point position M has been reached, the high-speed V _H is turned off and the low-speed _VL is simultaneously turned on to switch the speed. And the vehicle is decelerated at the second deceleration c (steps ST14 and ST15). Subsequently, it is determined whether or not the stacker crane 1 has reached the end point Pee of the low acceleration / deceleration section La (step ST16), and the end point Pe is determined.
e, the stacker crane 1 is moved to the first deceleration b
To decelerate the vehicle (step ST17).

Subsequently, the stacker crane 1 is moved to the low speed V _L
(Step ST14), the stacker crane 1 travels at a constant low speed _VL (Step ST1).
9) Finally, it is determined whether or not the stacker crane 1 has reached the braking position Pd (step ST20).
When d is reached, braking is applied (step ST21), and the stacker crane 1 is stopped at the target position OP.

The setting of the first acceleration a, the second acceleration b, the first deceleration d, and the second deceleration c
The control is performed by controlling the frequency of the driving power supplied from the first inverter to the driving motor 15. For example, it is assumed that the frequency of the driving power is changed from 0 Hz to KHz (reference frequency), and the time from 0 Hz to KHz is 10 minutes for the first acceleration a, 60 minutes for the second acceleration, and K
Time from 0 Hz to 0 Hz is 1 in the first deceleration.
It is set to 0 minutes and 60 minutes for the second deceleration. This allows
The first acceleration a, the second acceleration b, the first deceleration d, and the second deceleration c shown in FIG. 1 are obtained.

[0023]

As described above, according to the present invention, the following excellent effects can be obtained. (1) The predetermined high speed, first acceleration, second acceleration, first deceleration, second deceleration, and low speed are set, and the current position,
The traveling control can be performed at each acceleration deceleration in accordance with the first switching position, the start point, the intermediate point, the end point of the low acceleration / deceleration section, and the second switching position.

(2) As in the conventional traveling control method (see FIG. 7), an arithmetic operation is automatically performed in accordance with the traveling distance without storing various traveling patterns, and an approximate constant speed is obtained. A section (low acceleration / deceleration section) can be easily obtained.

[Brief description of the drawings]

FIG. 1 is a diagram for explaining a traveling control method of a moving object according to the present invention.

FIG. 2 is a diagram showing a schematic configuration of an automatic warehouse and a stacker crane.

FIG. 3 is a diagram showing a schematic configuration of an automatic warehouse and a stacker crane.

FIG. 4 is a block diagram illustrating a configuration of a control device.

FIG. 5 is a diagram showing a traveling control processing flow of the control device.

FIG. 6 is a diagram showing a traveling speed pattern of a conventional traveling control method for a moving body.

FIG. 7 is a diagram showing a traveling speed pattern of a conventional traveling control method for a moving body.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Stacker crane 2 Shelf 3 Travel rail 4 Overhead crane 5 Stacker crane main body 6 Post 7 Elevating stand 8 Fork 9 Pallet receiving stand 11 Pallet 12 Article 13 Loading part 14 Elevating drive motor 15 Traveling drive motor 16 Control board 17 Spring 18 Simulated wheel 19 Pulse encoder 20 Control unit 21 Travel drive unit 22 Elevation drive unit 23 Input device

Claims (1)

(57) [Claims] In order to cause a moving body to travel from a current position to a target position, the mobile body is accelerated at a first acceleration until a predetermined high speed is reached from the current position. The vehicle is caused to travel to a first switching position a predetermined distance before the target position, switched to deceleration traveling at a first deceleration at the first switching position, and switched to low-speed traveling at a second switching position a predetermined distance before the target position. In a traveling control method for a moving body in which a section from the second switching position to the target position is run at the low constant speed, braking is performed at a predetermined braking position, and the vehicle stops at the target position. If a predetermined high-speed constant-speed traveling section cannot be obtained before reaching the first switching position even when the vehicle is accelerated at the first acceleration from the position, the intermediate point position is determined from the difference between the current position and the target position. Calculate A low acceleration / deceleration section is set based on the intermediate point position, and the vehicle is accelerated at the first acceleration from a current position to a start point of the low acceleration / deceleration section. The vehicle is accelerated at a second acceleration significantly smaller than the first acceleration and decelerated at an intermediate point to an end point at a second deceleration significantly smaller than the first deceleration from the end point of the low acceleration / deceleration section to the second switching position. A traveling control method for a moving body, wherein the traveling speed is reduced at the first deceleration.