JP2564832B2 - Self-supporting unmanned vehicle - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a self-supporting unmanned vehicle that autonomously travels based on map data indicating a travel route.

[Prior Art] In recent years, with the progress of factory automation (FA), various types of unmanned vehicles that automatically convey parts and the like have been developed in factories, warehouses, etc. Among them, what are called self-supporting unmanned vehicles are By designating a destination node, it automatically searches for an optimal route and determines which node to pass through, and automatically travels to the destination node. Here, a node is a stop point, a branch point, a work point, or the like, and is a point at which a traveling state such as a traveling speed or a traveling direction of an unmanned vehicle changes.

FIG. 5 is a plan view showing a schematic configuration of this type of self-supporting unmanned vehicle (hereinafter referred to as unmanned vehicle) 1. The upper part of the drawing is the front surface of the unmanned vehicle 1.

In FIG. 5, 2L is the left drive wheel, 2R is the right drive wheel, 3L is the motor that rotates the left drive wheel 2L, 3R is the motor that rotates the right drive wheel 2R, and 4L is the rotational speed of the left drive wheel 2L. Are pulse encoders, 4R is a pulse encoder that detects the number of rotations of the right drive wheel 2R, and 5,5, ... Are wheels. These wheels 5,5, ...
Each of the wheels 5 is rotatable about its own axis, and is also rotatable about the axis perpendicular to the axis of each of the wheels 5, 5 ,. Reference numerals 6L and 6R denote ultrasonic transmitter / receivers (hereinafter referred to as ultrasonic sensors) for detecting the distance to the left and right side walls W, and 7 is a control device. As shown in FIG. 6, the control device 7 includes a CPU (Central Processing Unit) 8,
It has a program memory 9, a work memory 10, an interface circuit 11 and a motor drive circuit 12. A program for controlling the CPU 8 is written in the program memory 9. Further, the work memory 10 is written with map information regarding the traveling route. This map information is coordinate data indicating the coordinates of each node, map data regarding the distance from the planned travel route connecting each node to the left and right walls W, and the like. Here, FIG. 7 shows map data ML written in the work memory 10 and representing the distance to the left wall W. In this case, the map data ML is composed of data la _{1 to} lan indicating the distance from the planned traveling route of the unmanned vehicle 1 to the left side wall at every predetermined distance l. These data la ₁ ~ lan
Are each composed of 2 bytes. The map data MR (not shown) indicating the distance to the right wall W is also configured in the same manner as the map data ML described above.

Next, 13 is a communication device, which receives an instruction (indicating a destination node) sent from a central station (not shown) by radio. The instruction received by the communication device 13 is supplied to the control device 7.

In the unmanned vehicle 1 configured in this way, the CPU 8 performs the following traveling control according to the program written in the program memory 9.

First, when the CPU 8 is given a destination node from the central station, the CPU 8 searches for an optimum route based on the map information written in the work memory 10 and determines a node to pass through when going to the destination. . Then, the CPU 8 reads the distance to the left and right side walls W for each predetermined distance 1 from the one node to the next node based on the map data ML, MR for the appropriate flight. Then, the CPU 8 causes the motors 3L, 3R to travel at a constant speed along the planned travel route connecting the nodes in sequence.
Drive each. At this time, the CPU 8 measures the distance to the left and right walls W based on the signals respectively supplied from the ultrasonic sensors 6L and 6R for each predetermined distance l, and the pulse encoder
Based on the signals supplied from 4L and 4R, the traveling distance from the node that passed immediately before is measured. Then, based on these measurement results, it is determined whether or not the current traveling position deviates from the regular traveling position obtained based on the map information, and if it deviates, the position is corrected. As a result, the unmanned vehicle 1 always travels on the regular traveling position,
It passes through each node in sequence and reaches the target node.

[Problems to be Solved by the Invention] By the way, the above-mentioned conventional unmanned vehicle 1 has the following problems.

When the measurement interval for measuring the distance to the side wall W is shortened to improve the traveling accuracy, map data having the number of data commensurate with the number of measurements is required, which requires a huge memory capacity.

For example, the number of map data required to travel a distance l ₀ is required l ₀ / l, and if the distance to the side wall W is expressed with an accuracy of mm, the width of a general passage is on the order of meters. Therefore, one piece of map data requires a capacity of 2 bytes (16 bits). Here, l = 10 mm, l ₀ = 5000
If it is 000 mm, the map data capacity will be 2 × 5000000/10 = 10 ⁶ (bytes) .... Further, if the map data is provided on both the left and right sides, the total capacity of the map data will be twice as much as the formula.

By the way, if l is 50 mm, the memory capacity is 1/5 of the formula.
However, on the other hand, traveling control becomes rough and smooth traveling cannot be performed.

Since the map data is represented as the distance to the wall every time the unmanned vehicle travels a predetermined distance l, there is no reference map data within this distance l. For this reason, it is not possible to perform precise control of the traveling position.

Creating map data requires a lot of data, which is troublesome to create. Also, since the data is treated as numerical values, it is not easy for humans to understand.

As described above, in the conventional self-supporting unmanned vehicle having the map data including the data showing the distance to the side wall W at every constant distance interval (several tens of millimeters), the memory capacity becomes large and the detailed traveling position is fine. Cannot be controlled. In addition, there is a problem that it is difficult to comprehend the map data itself because it is troublesome to create the map data.

The present invention has been made in view of the above circumstances,
An object of the present invention is to provide a self-supporting unmanned vehicle that can reduce the memory capacity, can control the traveling position in detail, can easily create map data, and can easily understand the data content.

[Means for Solving Problems] In order to solve the above problems, the present invention predetermines nodes to pass in the process of traveling to a destination, and autonomously travels by sequentially passing through these nodes. In an unmanned vehicle,
From the map data composed of the scene code having an opcode indicating the lateral situation of the traveling route of the unmanned vehicle and the main operand indicating the continuation distance of the lateral situation of the traveling route by this operand, and from the map data according to the passage order of the nodes. It is characterized by comprising a travel control unit for reading out a corresponding scene command and controlling travel according to this scene command.

[Operation] According to the above configuration, the map data is composed of an operation code indicating the lateral situation of the traveling route of the unmanned vehicle and a scene command having a main operand indicating the continuation distance of the lateral situation of the traveling route by this operation code. Since the scene command is read from the map data during the period from the start of traveling to the end of traveling to perform proper traveling control, it is only necessary to allocate one scene command for each section of a certain form on the entire traveling route. Therefore, the data capacity as map data can be small. In addition, since the distance to the surroundings is continuous data, it is possible to perform fine control of the traveling position.
Further, there are advantages that map data can be easily created and that the contents of the scene command are easy to understand.

Embodiments Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a plan view showing a schematic structure of an unmanned vehicle 1'which is an embodiment of the present invention, and FIG. 2 is a block diagram showing an electric structure of the embodiment. In this embodiment, portions corresponding to those in FIGS. 5 and 6 described above are designated by the same reference numerals and the description thereof will be omitted. Further, in this embodiment, only the control device is different from the control device 7 of the conventional unmanned vehicle 1.

In FIG. 1, 7'denotes a control device. As shown in FIG. 2, this controller 7'has a CPU 8, a program memory 9 ', a work memory 10', an interface circuit 11 and a motor drive circuit 12. A program for controlling the CPU 8 is written in the program memory 9 '. Also. In the work memory 10 ', map information regarding the traveling route is written. This map information is coordinate data indicating the coordinates of each node, and map data indicating the form and continuity of the surrounding walls on the planned travel route connecting the nodes.

Here, the above-mentioned map data will be described in more detail.

Generally, walls in factories and offices are flat and continuous. Focusing on this point, the map data is represented by the shape of the wall and its continuity.

Hereinafter, as map data, three types of commands (commands) representing the form of the wall and its continuity were devised. These commands are called scene commands and are described as follows.

<WALL> :: = WALL (<distance>, <length>) <UNDEFINE> :: = UNDEFINE (<distance>, <lengt
h〉) <OPEN> :: = OPEN (<length>) (The units of distance and length are mm) The above scene commands are as shown in FIG. 3 with 1 word (2 bytes) opcode and 1 Alternatively, it is composed of 2-word operands. In this case, <OPEN> has a 1-word operand, and <WALL> and <UNDEFINE>
Has a 2-word operand.

 Next, the meaning of each scene command is as follows.

<WALL> indicates that there is a wall at the position indicated by <distance> and this wall is continuous for the distance indicated by <length>.

<UNDEFINE> has some information at a position more than the distance indicated by <distance>, or there is a wall that is difficult to measure with the ultrasonic sensor, so certain information cannot be obtained with the ultrasonic sensor, This state is continuous for the distance indicated by <length>.

<OPEN> indicates that nothing exists in the measurement range of the ultrasonic sensor, and this state continues for the distance indicated by <length>.

 Here, how to use <UNDEFINE> is explained.

For example, there is a door on the side of the travel route, and if this door is always open, <OPEN> can be used. However, <OPEN> cannot be used if it is closed even temporarily. Also, although it is usually a wall, <WALL> cannot be used if there are rarely items such as luggage. Use <UNDEFINE> in the above cases.

As described above, at least one side wall of the unmanned vehicle 1'represents each of the above commands as map data, and the work memory 1 as map information together with the coordinate data of each node.
Write to 0 '. Note that the above <distance> and <l
The standard length of ength〉 is several meters.

Next, the operation of this embodiment having the control unit 7'described above will be described. Further, in explaining this operation, the map data represented by the left and right side walls are used, that is, the map data ML ', MR' not shown is used.

Hereinafter, the CPU 8 controls according to the program written in the program memory 9 '.

First, when the CPU 8 receives a destination node from the central station, the CPU 8 searches for an optimal route based on the map information written in the work memory 10 ', and determines a node to pass through when going to the destination. To do. Then, the CPU 8 maps the form of the left and right side walls W from one node to the next node and the scene command indicating the continuity thereof to the map data M.
Read the appropriate flight from L ', MR'.

Here, FIG. 4 shows the form of the left and right side walls W between the node Ni and the node Ni + 1 and their continuity. The scene command in this case is as follows.

The left side W is (a) WALL (<3000>, <5000>) (b) UNDEFINE (<3000>, <1000>) (c) WALL (<3000), (6000)).

Regarding the right side wall W, it is (a) 'OPEN (<6000>) (b)' UNDEFINE (<3800>, <6000>).

(The unit is mm) Hereinafter, the operation when the unmanned vehicle 1'runs between the nodes Ni and Ni + 1 by the scene command described above will be described with reference to this figure.

First, the CPU 8 recognizes the form of the left side wall W by decoding the scene command (a). In this case, the left side wall W is <WAL
L>, the distance from the left side wall W is 3000 mm, this <WALL> is 500
0 mm continues. Next, the CPU 8 decodes the scene command of (a) 'and recognizes the form of the right side wall W. in this case,
The right side wall W is <OPEN>, and this <OPEN> continues for 6000 mm. Then, the CPU 8 ignores the scene command of (a) ′ as a reference for traveling, and ignores this, so that the motor 3 operates so as to travel at a constant speed in accordance with the scene command of (a).
Drive L and 3R (Fig. 1) respectively. At this time, the CPU 8 is a signal supplied from the ultrasonic sensor 6L (always transmitted).
The distance to the left side wall W is measured based on the above, and the measurement result is compared with the distance of 3000 mm to determine whether or not the vehicle is deviating from the regular planned traveling position. In this case, if it deviates, the motor control circuit 12 is controlled so that the motor control circuit 12 comes to the normal position. Then, the CPU 8 travels for a distance of 5000 mm while counting the signals supplied from the pulse encoders 4L and 4R.

Next, just before the unmanned vehicle 1'has finished traveling a distance of 5000 mm,
The CPU 8 decodes the next scene command ((b)) and recognizes the form of the left side wall W. In this case, the left side wall W is <UNDEFIN
The distance to E> and <UNDEFINE> is 3000 mm.
E〉 continues for 1000 mm. In addition, <UNDEF shown here
INE〉 indicates a door. Next, the CPU 8 sets the right side wall W
Is still in the <OPEN> form and continues to be ignored. OPU8 also ignores this because the scene command of (b) does not serve as a reference for running, and runs at a constant speed while maintaining the previous state. At this time, while counting the signals supplied from the pulse encoders 4L and 4R, the distance of 1000mm
To run.

Next, immediately before the unmanned vehicle 1'has finished traveling for a distance of 1000 mm, the CPU 8 decodes the next scene command ((c)) and recognizes the state of the left side wall W. In this case, the left side wall W is <WAL
L>, the distance from the left side wall W is 3000m, this <WALL> is 6000
mm continues. Then, the CPU 8 decodes the scene command of (c) ′ and recognizes the form of the right side wall W. In this case, the right side wall W is <UNDEFINE>, and the distance to this <UNDEFINE> is
3800mm, <UNDEFINE> continues 6000mm. In addition, <UNDEFINE> shown here shows the case where the luggage is placed parallel to the wall. Then, the CPU 8 ignores the scene command of (C) ′ and travels at a constant speed for a distance of 6000 mm in accordance with the scene command of (C). At this time, the distance to the left wall W is measured, and the traveling position is corrected within the distance of 6000 mm so that the distance to the left wall W becomes constant. Then, after traveling a distance of 6000 mm, the node reaches the node Ni + 1.

After that, the same operation is performed each time the scene command is decoded after the node Ni + 1, and finally reaches the target value.

Control of the traveling position of the unmanned vehicle 1'when another unmanned vehicle travels from the front will be described.

First, while the unmanned vehicle 1 ′ is traveling in the section specified by <WALL> and <UNDEFINE>, another unmanned vehicle 1 ″ (not shown) is approaching from the front and collides with it. If there is a risk of this, the unmanned vehicle 1'determines itself and changes the driving position so as to avoid within the distance indicated by <distance>. In this case, within the distance indicated by <distance>. If it is not possible to avoid it, ask another unmanned vehicle 1 ″ to change its travel position.

Next, if the unmanned vehicle 1'is approaching from the front while the unmanned vehicle 1'is traveling in the section specified by <OPEN>, and there is a risk of collision with it. Since the unmanned vehicle 1'has no limit on the distance to the surroundings, the traveling position is changed by setting the distance that can avoid a collision arbitrarily. In this case, the section specified by <OPEN> is wide enough. There is no need to ask another unmanned vehicle 1 ″ to change the driving position.

As described above, the map data according to the present invention has a larger capacity of one data than the conventional map data,
The total map data capacity is small. Further, since the map data according to the present invention handles the distance to the wall as continuous, it is possible to finely control the traveling position. Also, scene commands such as <WALL>, <UNDEFUNE>, and <OPEN> are easy to understand and easy to create as map data because they are in the form suitable for human thinking.

In the embodiment of the present invention, the ultrasonic sensor was used to detect the surrounding morphology, but an image using a device using a laser beam instead, a CCD (charge coupled device), or the like. The shape of the wall may be detected by an input device or the like.

Further, in the embodiment of the present invention, three scene commands are used, but if the form of the wall or surroundings is complicated, it is possible to add a scene command corresponding to it.

[Effects of the Invention] As described above, according to the present invention, in a self-supporting unmanned vehicle in which a node passing through in the process of traveling to a destination is determined in advance and the vehicle travels by sequentially passing through each of these nodes, the unmanned vehicle travels. Map data composed of scene code having an opcode indicating the lateral situation of the driving route and a main operand indicating the continuation distance of the lateral situation of the driving route by this opcode, and a scene corresponding from the map data according to the passage order of the nodes. Since a travel control unit for reading out commands and controlling travel by the scene commands is provided, the scene command composing the map data is required to be one for every several meters on average for the wall, so the memory capacity is reduced. be able to. Further, since the distance to the wall is used as continuous data, the control of the traveling position does not depend on the map data, and the precise control of the traveling position can be performed. Further, it is easy to create map data and the contents of the scene command are easy to understand.

[Brief description of drawings]

FIG. 1 is a plan view showing a schematic configuration of an embodiment of the present invention,
FIG. 2 is a block diagram showing an electric configuration of the embodiment, and FIG.
FIG. 4 is a diagram showing map data used in the same embodiment, FIG. 4 is a diagram for explaining the operation of the same embodiment, FIG. 5 is a plan view showing a schematic configuration of a conventional self-supporting unmanned vehicle, and FIG. FIG. 7 is a block diagram showing an electrical configuration of the self-supporting unmanned vehicle, and FIG. 7 is a diagram showing map data used for the self-standing unmanned vehicle. 1 '... self-supporting unmanned vehicle, 7' ... control device (travel control unit), 10 '... work memory (map data is written), W ... wall.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Yuji Nishikawa 100 Takegahana-cho, Ise City, Ise Factory, Shinko Electric Co., Ltd. (56) References JP 62-49412 (JP, A) JP 60-204012 (JP, A)

Claims (4)

(57) [Claims] Claims: 1. A self-supporting unmanned vehicle in which a node to pass through in the process of traveling to a destination is determined in advance, and an autonomously-running unmanned vehicle that travels by passing through each of these nodes, and an opcode indicating a lateral condition of a traveling route of the unmanned vehicle, and The map data composed of a scene command having a main operand indicating the continuation distance of the side situation of the traveling route by this operation code, and the corresponding scene command are read from the map data according to the passage order of the nodes, and the traveling control is performed by this scene command. A self-supporting unmanned vehicle characterized by comprising a traveling control unit. 2. The scene command is composed of an operation code indicating a flat wall, the main operand, and a sub-operand indicating a constant distance from the wall to a travel route. The self-supporting unmanned vehicle according to claim 1. 3. The scene command includes an opcode for indicating a situation where it is impossible to determine whether or not a door or luggage is always present, the main operand, and a sub-operand indicating a predetermined distance from the travel route to the situation. The self-supporting unmanned vehicle according to claim 1, characterized in that 4. The self-supporting unmanned system according to claim 1, wherein the scene command is composed of an operation code which is a space and indicates a situation in which distance measurement is impossible, and the main operand. car.