JPH04123113A - Stop controller for moving car - Google Patents

Abstract

PURPOSE:To smoothly and exactly stop the moving car at a stop position by knowing a distance from storage information of a storage medium installed in this side part of a mark, even if the distance between the stop position and the its mark installed in this side part is not constant, and decelerating the moving car so as to reach a slow speed in the vicinity of the stop position. CONSTITUTION:A controller 9 operates a decelerating device 100 from a distance extending from a mark M1 detected by a mark sensor 6 to a stop position, a running distance from the mark M1 measured by a running distance measuring means 14, a running speed and a slow speed detected by a speed detecting means 15, and a time point calculated, based on the degree of deceleration of a decelerating device 100. In such a state, when the mark sensor 6 detects a mark M2 after reaching the slow speed, a damping device 13 is operated immediately. In such a way, even if the distance between the stop position and the mark installed in its this side part is not constant, the moving car is decelerated so as to reach the slow speed in the vicinity of the stop position, and can be stopped at the stop position.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention provides a method for gradually decelerating a mobile vehicle automatically traveling along a guide line from before a predetermined stop position to a creeping speed, and then returning to the stop position. The present invention relates to a stop control device for a moving vehicle to be stopped.

[Conventional technology]

Such a stop control device for a moving vehicle is used to prevent the cargo from collapsing or to prevent the cargo from collapsing when stopping a moving vehicle transporting loads such as assembled parts and work-in-progress at a predetermined stop position in a product assembly factory, for example. It is used for the purpose of stopping the vehicle smoothly to avoid impact. Furthermore, in order to accurately stop the vehicle at the stop position, the vehicle is decelerated to a creeping speed before the stop position.

Incidentally, the creeping speed referred to here is a speed at which the moving vehicle can be stopped immediately on the spot.

When stopping a moving vehicle, the propulsion force is stopped and at the same time, braking is generally applied.

Conventionally, in order to perform control to gradually decelerate to a slow speed and then stop as described above, a mark is placed at a predetermined distance in front of the stopping point, and the moving vehicle detects the mark. Accordingly, a method is generally adopted in which the creeping speed is gradually reduced.

[The problem that the invention attempts to solve]

From the viewpoint of conveyance efficiency, it is preferable that the traveling at the above-mentioned slow speed be as short as possible. Therefore, one possible method is to calculate the point in time at which deceleration should start based on the initial speed, deceleration, and distance to the stop position so that the creeping speed is reached near the stop position. Therefore, the distance between the reference mark and the stop position must be a constant value.

However, since there are many different stopping positions, it is difficult to place marks at equal distances from each other at all stopping positions throughout the equipment.

For example, it may be necessary to shift the installation position to avoid interference with marks installed for other purposes. Also, the stop position may move slightly due to changes in layout, etc.

The present invention has been made in view of the above circumstances, and its purpose is to drive a moving vehicle slowly near the stop position even if the distance between the stop position and the mark installed in front of the stop position is not constant. An object of the present invention is to provide a stop control device for a moving vehicle that can decelerate the vehicle to reach a speed and stop it at a stop position.

[Means for solving problems]

A stop control device for a mobile vehicle according to the present invention is for gradually decelerating a mobile vehicle automatically traveling along a guide line from before a predetermined stop position to a creeping speed, and then stopping the vehicle at the stop position, The first characteristic configuration is that a storage medium in which stored information can be freely rewritten and a mark indicating a reference point are provided at a predetermined distance from the top side along the traveling direction of the moving vehicle at a location in front of the stop position; The storage medium stores at least distance information from the mark to the stop position, and the moving vehicle includes a reading means for reading the information stored in the storage medium, a mark sensor for detecting the mark, and a distance measuring device. and a deceleration device for decelerating the moving vehicle at a predetermined deceleration, the vehicle being configured to reach the creeping speed near the stop position based on the distance information, the distance traveled from the mark, and the deceleration. A control device is provided which calculates the point in time at which deceleration should start and operates the deceleration device from that point.

Further, a second characteristic configuration of the mobile vehicle stop control device according to the present invention specifies a preferable configuration when implementing the first characteristic configuration, and includes a speed at which the traveling speed of the mobile vehicle is detected. A detecting means is provided, and the control device is configured to calculate the time point at which the deceleration should start based also on traveling speed information detected by the speed detecting means.

[For production]

The stop control of the moving vehicle according to the first characteristic configuration described above is performed as follows.

To explain with reference to FIG. 4, the moving vehicle travels along the guide line, and as it approaches the stop position, first, the storage information of the storage medium (T) is read by the reading means, and the vehicle stops from the mark (M1). Know the distance to the location. Based on the deceleration inherent in the deceleration device, the vehicle control device then
Calculate the distance traveled from the start of deceleration to the time the vehicle reaches creeping speed. This distance plus an appropriate safety distance is the distance D', or the distance from the point where deceleration should start to the stopping position.

Eventually, the mark (M1) is detected by the mark sensor, and the subsequent mileage R is measured by the mileage measuring means. The control device determines the difference between the distance and the traveling distance R (
LR), that is, when the distance from the moving vehicle to the stop position becomes equal to the distance D', the deceleration device is activated to start deceleration. As a result, the mobile vehicle reaches its creeping speed close to the stop point, ie before said safety distance.

In addition, in order to stop the mobile vehicle at the stop position, the traveling distance (
Is it possible to determine that the vehicle has reached the stop position based on the determination result (R) and stop the moving vehicle based on the determination result?Generally, as shown in FIG. M2) is often installed, and the moving vehicle is often configured to stop when it detects this mark (M2).

In addition, since the information stored in the storage medium can be rewritten, even if the stop position is moved slightly due to layout changes, there is no need to change the installation position of the storage medium or mark, just rewrite the information stored in the storage medium. It is possible to deal with this.

Further, according to the second characteristic configuration, since the speed detecting means detects the traveling speed of the moving vehicle, appropriate stop control can be performed even when the traveling speed of the moving vehicle fluctuates. In other words, when a moving vehicle is operated at a constant speed along a guidance line, the traveling speed of the moving vehicle can be preset and memorized to determine the point at which deceleration should start, even if there is no speed detection means. can be calculated appropriately. However, if the traveling speed of the moving vehicle is changed in various sections of the guide line, appropriate stop control can be performed by having the speed detecting means detect the traveling speed.

C Effect of the invention] Therefore, even if the distance between the stop position and the mark installed in front of the stop position is not constant, the distance can be known from the information stored in the storage medium installed in front of the mark and the moving vehicle can be moved. Since it is possible to decelerate the vehicle to reach the creeping speed near the stop position, it is possible to stop the vehicle smoothly and accurately at the stop position, and it is also possible to minimize the length of time the vehicle travels at the creeping speed before stopping. It became so. Therefore, we have achieved a highly flexible stop control device for a moving vehicle that can contribute to improving transport efficiency and can easily accommodate layout changes.

〔Example〕

Embodiments of the present invention will be described below based on the drawings.

As shown in FIG. 1, a guide line (L) is provided in a loop shape along the travel route of a transport vehicle (A),
A plurality of stations (ST) are provided along the guide line (L) for the moving vehicle (A) to stop and perform tasks such as loading and unloading cargo, thereby allowing the moving vehicle (A) to move between each station. The conveyance equipment is configured to carry out load conveyance work while automatically traveling.

As shown in Figure 2, the guiding line (L) is made by embedding a magnetic material in the road surface, which has a rectangular cross section and is magnetized with N pole on the front side and S pole on the back side, and fixing the periphery with epoxy resin so that the road surface is It is constructed so that it is flush with the surface.

Each station (ST) is equipped with a mark (M) for automatically stopping the moving vehicle (A) and a storage medium (T) called an ID tag that stores stop control information.

The mark (M) is as shown in Fig. 2, when the front side of the magnet piece is S.
The pole is buried in the road surface so that the back side is the north pole. In addition, the mark (M) indicates the stop position (
M2) and a mark (M1) indicating a reference point for starting deceleration control.

The ID tag (T) is not shown, or is a casing that includes a rewritable semiconductor memory (RAM), a controller having communication means with external equipment, and a battery. The communication means is wireless two-way communication using electromagnetic induction, and allows the memory information 1[7 to be rewritten or read from the outside without contact. The stored information is then retained by a battery.

As will be described in detail later, as the moving vehicle (A) approaches the installation location of the ID tag (T), it reads the stop control information stored therein, then detects the mark (M), and reads the stop control information. Based on the mark detection information, stop control is performed to stop at a predetermined stop position.

As shown in the block diagram and plan view of the main parts of the moving vehicle (A) in FIGS. motor(
A running wheel (3) which also serves as a steering wheel is provided which is steered at step 2), and a pair of left and right driven wheels (4) are provided on the rear side of the vehicle body. A magnetic sensor (5) for detecting the guide line (L) and obtaining information for steering control is installed in front of the running wheel (3) so that the direction can be changed integrally with the running wheel (3). It is being A mark sensor (6) for detecting the above-mentioned mark (M) is provided at the front right side of the vehicle body. The mark sensor (6) is also a kind of magnetic sensor, and detects the mark (M), which is a piece of magnet, by coming close to it.

A tag reader (7), which is a reading means for reading the memory information of the aforementioned ID tag (T), is provided at the front left side of the vehicle body. This tag reader (7) is an ID tag (T)
As it approaches, it performs two-way communication using electromagnetic induction and reads its stored information.

A communication device (8) having a light emitting element and a light receiving element is provided in the center left side of the vehicle body. Also, when the moving vehicle (A) or the station (ST) is stopped, the station (ST)
A communication device (CM) having a light-emitting element and a light-receiving element is also provided at the opposite position on the ) side, thereby performing communication between the station (ST) and the mobile vehicle (A). Alternatively, communication is performed between the central control unit (C) that manages the operation of the entire facility and the moving vehicle (A) by relaying the station (ST). For example, a moving vehicle (A) or a station (
When the station (ST) notifies the completion of work at that station (ST), the moving vehicle (A) is sent from the station (ST).
Address information of the target station to which the user should move and work next is specified.

In addition, the moving vehicle (A) includes the above-mentioned sensors (5).

(6), a control device (9) equipped with a microcomputer for processing information obtained through the tag reader (7) and the communication device (8) and controlling the travel of the mobile vehicle (A)
Or is provided. Furthermore, a drive device (lO) for the driving motor (1) and a drive device (11) for the steering motor (2).
, an electromagnetic brake (13) for braking the running wheels (3)
The controller (9) also controls these.

Further, the control device (9) is configured to also execute a control operation for decelerating the traveling motor (1) at a predetermined deceleration. In other words, the speed reduction device (100) is configured using the control device (9).

The traveling distance of the moving vehicle (A) is measured by the traveling distance measuring means (14) from the output of a rotary encoder (RE) that generates pulses as the traveling wheels (3) rotate. Further, the traveling speed of the mobile vehicle (A) is detected by a speed detecting means (15) which has a timekeeping function and calculates the traveling speed from the traveling distance per unit time. These travel distance information and travel speed information are input to the control device (9) and become information necessary for stop control, which will be described later.

The magnetic sensor (5) consists of four magnetic sensing elements arranged in the width direction of the vehicle body, as shown in FIGS. 2 and 3. Then, the position of the moving vehicle (A) in the width direction is at an appropriate position with respect to the guide line (L), that is, the center of the width direction of the magnetic sensor (5) is aligned with the guide line (L).
at a predetermined interval so that the inner two of the four magnetic sensing light-receiving elements sense the magnetism from the guide line (L), and the outer two do not. It is separated by

Therefore, when the moving vehicle (A) deviates to the left or right with respect to the guide line (L), either of the two outer magnetic sensing elements will be in a state where it senses the magnetism due to the guide line (L). Based on the detected information, the device (9) performs steering control to return the vehicle body to an appropriate position with respect to the guide line (L).

The tag reader (7), which is not shown in the figure, consists of a communication means for communicating with the ID tag (T) by electromagnetic induction, and a controller thereof, and is configured to communicate with the ID tag (T). The read information is transmitted to the control device (9). Then, while the moving vehicle (A) is running, at a constant cycle,
A signal requesting the ID tag (T) to transmit its stored information is transmitted. On the other hand, the ID tag (T) is maintained in a state where it can receive the transmission request signal from the tag reader (7). Therefore, moving vehicle (A) force D tag (
When the ID tag (T) approaches the installation location of the tag reader (7) and the distance between the ID tag (T) and the tag reader (7) approaches the communicable distance, the ID tag (T) receives a transmission request signal from the tag reader (7). , returns a response.

Either omit the explanation of the communication protocol that follows, or enter the ID here.
Communication between tag (T) and tag reader (7) is established, and the ID
The stored information of the tag (T) is transmitted to the tag reader (7). In this way, the mobile vehicle (A) can automatically read the stored information of the ID tags (T) installed at predetermined locations along its travel route using the tag reader (7) while traveling.

As mentioned above, the storage information to be stored in the ID tag (T) is stored in the mobile vehicle (A) at each station (ST).
This is stop control information for automatically stopping the system, or specifically the following information.

■ Must be in front of the station (ST). ■ Address of the station (ST).

■ Distance L0 from mark (M1) to stop position, that is, mark (M2) As the moving vehicle (A) approaches the ID tag (T), it transfers the above stop control information stored in it to the tag reader (7).
) and know that it is before the station (ST). Then, it is checked whether the address of the station (ST) matches the address of the target station instructed in advance and stored in the memory in the control device (9).

If they do not match, they pass through as is, and if they match, the following stop control is performed.

That is, the control device (9) is in charge of the above-mentioned information (2), that is, the distance from the mark (M1) to the stop position, which will be detected by the mark sensor (6), and the mark measured by the mileage measuring means (14). The time point is determined as described below based on the traveling distance R from (M1), the traveling speed V detected by the speed detecting means (15), the creeping speed ■, and the deceleration a of the deceleration device (100). From reduction gear (100)
Activate. When the mark sensor (6) detects the mark (M2) after reaching the creeping speed V, the braking device (13) is immediately activated. Here, the creeping speed V is the moving vehicle (
A) is the slowest travel speed that can be controlled, and when the braking device (13) is activated, the vehicle can be stopped immediately on the spot.

The control device (9) is configured to maintain the creeping speed V near the stop position so that traveling at the creeping speed V can be completed in as short a time as possible.
The point in time at which deceleration should be started is calculated as follows.

If the deceleration a is constant, the distance traveled by the moving vehicle (A) from when it starts decelerating from the running speed V until it reaches the slowing speed ■ is given by D=(V-v)2/(2a). Calculated. Therefore, add an appropriate safety distance to this distance and get the distance D.
If the vehicle starts decelerating at point ', the vehicle will reach the slow speed ■ near the stop position, that is, just a safe distance before the vehicle stops.

After detecting the mark (M1), the distance from the moving vehicle (A) to the stop position is determined by the difference between the distance from the mark (M1) to the stop position and the traveling distance R from the mark (M1) (
LR), so the time point when this value becomes equal to the above distance D is the time point to seek (4th
(see figure).

As described above, the mobile vehicle (A) travels along the guidance line (L), and when it reaches the target station (ST), the stop control information and mark detection information read from the ID tag (T) After the vehicle gradually decelerates from an optimal point calculated in accordance with the travel speed and reaches a creeping speed, it is possible to accurately and smoothly stop at a predetermined stop position.

Note that writing information to the ID tag (T) is not shown in the drawings, or is performed using a portable handy terminal equipped with an electromagnetic induction type communication device like the tag reader (7). Alternatively, a mobile vehicle programmed to write the ID tag (T) may be used to write the ID tag (T) without traveling along the guide line (L).

If the position of the station (ST) changes due to layout changes, etc., and if the station (ST) is moved slightly, the stored information of the ID tag (T) installed at the front of each station can be written using the above writing device. By simply rewriting, this can be done without changing the installation position of the marker (M) or ID tag (T).

[Other actual flow side]

In the above embodiment, the speed reduction device (100) is not limited to controlling the rotation speed of the travel motor (1), but for example, it simply stops the travel motor (1) and applies a constant braking force to the wheels. It may be configured as follows. However, in the second case, the mobile vehicle (A) decelerates at a deceleration determined by its inertial mass, rolling friction force, braking force of the deceleration device (12), etc., and eventually comes to a stop. 13)
must be activated and stopped at a predetermined stop position. Therefore, under various conditions, the speed will not always be lower than the creeping speed near the stop position, resulting in inferior stability compared to the above embodiment.

The physical structure of the guide line (L) is not limited to that of the above-mentioned embodiment, but may be one in which a magnetic tape is attached to the running road surface, for example. Or it is attached with light reflective tape,
The present invention is also applicable to the case where the moving vehicle (A) is provided with an optical sensor instead of the magnetic sensor (5). Furthermore, the vehicle may be mechanically guided and run along a guide rail, such as a mole rail.

It should be noted that the present invention is not limited to the structure of the attached drawings, whether or not reference numerals are written in the claims for contrast with the drawings or for convenience.

[Brief explanation of drawings]

Each figure shows an embodiment of the stop control device for a moving vehicle according to the present invention, and FIG. 1 is a plan view showing the layout of the entire conveyance equipment;
Figure 2 is a block diagram showing the moving vehicle and the flow of signals around it, Figure 3 is a plan view showing the schematic structure of the moving vehicle and its relationship with the stop position, etc., and Figure 4 is an explanatory diagram of the stop control. be. (A)...Moving vehicle, (L)...Guidance line, (M1)...Mark, (T)...
・Storage medium, (6)...Mark sensor, (7)
...Reading means, (9) ... Side device,
(14)... Mileage measuring means, (15)...
...speed detection means, (100) ... deceleration device.

Claims (1)

[Claims] 1. A mobile vehicle (A) that automatically travels along a guidance line (L)
) is a stop control device for a mobile vehicle (A) that gradually decelerates the vehicle (A) from before a predetermined stop position to a slow speed and then stops the mobile vehicle (A) at a location before the stop position. A storage medium (T) in which stored information can be freely rewritten and a mark (M1) indicating a reference point are provided at a predetermined distance from each other in order from the upper side along the traveling direction of the storage medium (T), and at least the mark (M1) is provided on the storage medium (T). Distance information from (M1) to the stop position is stored, and the moving vehicle (A) includes a reading means (7) for reading the information stored in the storage medium (T), and a reading means (7) for detecting the mark (M1). mark sensor (6), and distance measuring means (14)
and a deceleration device (100) that decelerates the moving vehicle (A) at a predetermined deceleration, and determines the stop position based on the distance information, the traveling distance from the mark (M1), and the deceleration. A stop control device for a moving vehicle, comprising a control device (9) that calculates a point in time at which deceleration should be started so as to reach the creeping speed soon, and operates the deceleration device (100) from that point. 2. The stop control device for a moving vehicle according to claim 1, wherein the moving vehicle (A) is provided with speed detection means (1) for detecting a running speed.
5), and the control device (9) is configured to calculate the time point at which the deceleration should start based also on the traveling speed information detected by the speed detection means (15). Car stop control device.