CN111052023A

CN111052023A - Moving body guide system

Info

Publication number: CN111052023A
Application number: CN201880052417.9A
Authority: CN
Inventors: 伊藤顺治
Original assignee: Nidec Corp
Current assignee: Nidec Corp
Priority date: 2017-09-14
Filing date: 2018-08-31
Publication date: 2020-04-21
Also published as: WO2019054206A1; JPWO2019054206A1

Abstract

The present invention provides a mobile body guidance system (1), (2) having: a plurality of moving bodies (10); a positioning device (30) that measures the position of each mobile body and outputs position information of each mobile body; a guide device (20) that generates a guide command for guiding each mobile body for each mobile body; and an arithmetic device (40) which confirms the movement path of each mobile body with reference to each guide command and predicts whether or not a collision between the mobile bodies occurs. The arithmetic device has a communication circuit (47) and an arithmetic circuit (45), and the arithmetic circuit (45) determines the coordinates of a passage point of at least one moving body based on the guidance instruction of each moving body, and predicts whether or not a collision between the moving bodies occurs based on the data of each moving speed. After the guide command is transmitted to each of the mobile bodies, when the arithmetic circuit (45) predicts that a collision between the mobile bodies occurs, the guide device generates a new guide command for each of the mobile bodies and transmits the guide command to each of the mobile bodies. Each mobile body moves in accordance with the new guidance instruction.

Description

Moving body guide system

Technical Field

The present invention relates to a mobile body guidance system.

Background

Systems for controlling the movement of a mobile body such as an automated guided vehicle have been developed.

International publication No. 2008/035433 discloses a mobile body having a tag communication unit. A plurality of IC tags having respective pieces of position information are distributed in the travel target area. When the mobile body travels, the tag communication unit wirelessly communicates with the IC tag to read the positional information of the IC tag. Thus, the mobile object can acquire information on the current position and automatically travel.

Japanese patent application laid-open No. 11-154013 discloses a system for moving an Automated Guided Vehicle (AGV) to a specified position. The AGV reads a position mark indicating a position, and corrects the positional deviation of the AGV using its own navigation system when the AGV moves to a specified position.

Documents of the prior art

Patent document

Patent document 1: international publication No. 2008/035433

Patent document 2: japanese laid-open patent publication No. 11-154013

Disclosure of Invention

Problems to be solved by the invention

Conventional mobile bodies perform height control while collecting data indicating the position of their own apparatus, and automatically travel to a destination. Such a mobile body requires a high-performance processor, a large-capacity memory, a high-performance sensor, and the like, and therefore the cost of the system increases.

For example, in both of the techniques of

patent documents

1 and 2, an IC tag or a position mark necessary for detecting a position is disposed in a travel area, and the moving object itself detects the current position and is used for automatic travel. A reading device for reading the positional information and a device for performing automatic traveling using the positional information are required, and the cost of the mobile body increases.

Further, if the number of moving bodies that perform automatic traveling increases, a problem may arise in which automatic traveling is performed only by each moving body, which is unavoidable. For example, a collision of a moving body quality inspection. In order to avoid these problems, if mutual communication is performed between mobile units, the cost for mutual communication is also required.

An object of the present disclosure is to provide a mobile body guidance system that can be introduced and operated at low cost and can avoid collision of mobile body quality inspection.

Means for solving the problems

An exemplary moving body guide system of the present disclosure is a moving body guide system that guides each of a plurality of moving bodies, the moving body guide system including: a plurality of moving bodies; a positioning device that measures a position of each of the moving bodies and outputs position information of each of the moving bodies; a guidance device that generates a guidance command for guiding each of the moving bodies for each of the moving bodies; and an arithmetic unit that checks a movement path of each of the moving objects with reference to the guidance instruction of each of the moving objects, and predicts whether or not a collision between the moving objects occurs, each of the moving objects including: a sensor that detects a moving speed of the moving body; a first communication circuit that receives the guidance command and transmits data of the movement speed; a power source that generates a driving force; and a drive device that controls the power source according to the guide command to move the movable body, wherein the guide device includes: a signal processing circuit that generates the guidance instruction; and a second communication circuit that communicates with the mobile units, wherein the arithmetic device includes: a third communication circuit that receives the guidance command and the data of the moving speed of each of the moving objects; and an arithmetic circuit that determines coordinates of a passage point of at least one moving body based on the guide command for each moving body, and predicts whether or not a collision between the moving bodies occurs based on the data of the moving speed, wherein the guide device executes the following control: generating the guide command for specifying a movement path of each of the moving objects; transmitting the guidance command to each of the moving bodies; an arithmetic circuit of the arithmetic device generates a new guidance command for each of the moving objects when it is predicted that a collision between the moving objects occurs; and transmitting the guidance command to each of the mobile bodies, wherein each of the mobile bodies moves according to the received new guidance command.

Effects of the invention

According to the moving body guidance system exemplified in the present application, the positioning device measures the position of each moving body, and generates a guidance command for guiding each moving body by the guidance device. When a collision between moving bodies is predicted to occur, a new guidance instruction is generated for each moving body. This can avoid collision between moving bodies.

Drawings

Fig. 1 is a diagram schematically illustrating a configuration of an exemplary mobile body guidance system.

Fig. 2A is a diagram showing each guide command transmitted to 3 mobile units.

Fig. 2B is a diagram showing an example of the movement path of 3 mobile bodies.

Fig. 3A is a diagram showing a new guidance command for each mobile object generated by the guidance device.

Fig. 3B is a diagram showing an example of the movement path of each moving object according to the new guidance command.

Fig. 4 is a diagram schematically showing the configuration of the moving body guidance system.

Fig. 5 is a block diagram showing a configuration of an IC tag mounted or built in each mobile body.

Fig. 6 is an external view of an exemplary mobile object according to the present embodiment.

Fig. 7 is a block diagram showing a hardware configuration of a mobile unit.

Fig. 8 is a diagram showing a hardware configuration of the guidance device.

Fig. 9 is a diagram showing a hardware configuration of the positioning device.

Fig. 10 is a diagram showing a hardware configuration of the arithmetic device.

Fig. 11 is a diagram showing a hardware configuration of the storage device.

Fig. 12 is a diagram showing communication performed in the moving body guidance system and a processing procedure of the moving body, the guidance device, the positioning device, and the arithmetic device.

Fig. 13 is a diagram showing an example of a configuration in which the HDD array of the storage device and the guide device are housed in one housing.

Detailed Description

Hereinafter, the moving body guidance system of the present disclosure will be described.

In the moving body guidance system of the present disclosure, a destination and a movement route are set for each of 1 or a plurality of moving bodies, and the moving bodies automatically move. The mobile body has an IC tag (IC tag). The "IC tag" is an electronic device that periodically or intermittently transmits unique identification information, and is incorporated in a housing of a mobile object or the like.

The position of each moving body is measured by a positioning device provided in a moving space of the moving body. The measurement is performed periodically, for example, at intervals of several seconds. When the mobile body moves, the positioning device can acquire the position of the mobile body after the movement.

The guide command generated by the guide device specifies the movement path of each mobile body. The guide device transmits a guide command to each of the moving bodies to move the moving bodies along the movement path.

The moving body may be, for example, an Automated Guided Vehicle (AGV), a self-propelled cart or wheelchair, an autonomous or autonomous driving vehicle, a robot, a multi-rotor (multicopter), or a service robot. The "position" may be a position in a two-dimensional plane or a position in a three-dimensional space.

An example of a use of the moving body guide system is to transport an object by independently moving a plurality of AGVs along respective movement paths in a facility such as a factory.

Hereinafter, the moving body guidance system of the present disclosure will be described with reference to fig. 1.

Fig. 1 schematically shows the configuration of an exemplary moving body guide system 1. The mobile body guidance system 1 includes a plurality of

mobile bodies

10X, 10Y, and 10Z, a guidance device 20, a positioning device 30, and an arithmetic device 40. In fig. 1, an AGV is illustrated as a moving body. The moving body is collectively referred to as "moving body 10".

In the present embodiment, each mobile unit 10 transmits and receives data by radio. Therefore, fig. 1 shows the relay device 32. The relay device 32 is a device that relays wireless communication and has a transmission antenna 33 and a reception antenna 34. The relay device 32 may be included in or excluded from essential components of the mobile guidance system 1.

The guidance device 20 includes a signal processing circuit that generates a guidance command for each mobile body 10 and transmits the guidance command using a communication circuit. Each guide command indicates a movement path of each mobile body 10. In the present embodiment, the movement path is represented by coordinates of 1 or more positions to be passed from the current position as a starting point. The coordinates of the last position represent the end point. The guidance command may include a command for instructing movement stop, as described later. The guide device 20 guides each mobile body 10 by a guide command.

When the guide device 20 generates a guide command, the guide device 20 acquires position information of each mobile body 10. The position of each mobile body 10 is measured by the guide device 20 using a signal wave transmitted from the IC tag of each mobile body 10.

Each mobile body 10 has an IC tag not shown. An IC tag is an electronic device that transmits unique identification information (RFID) that uniquely identifies itself. The identification information is held in advance in the IC tag and transmitted by radio waves. The IC tag periodically transmits the identification information, for example, every 0.1 second. The identification information transmitted from the IC tag is received by the receiving antenna 34 of the relay device 32. The identification information of the IC tag can be utilized as identification information that uniquely identifies each mobile body 10.

Each of the mobile bodies 10 includes a sensor for detecting a moving speed of the apparatus, a communication circuit for receiving a guide command and transmitting data of the moving speed, a power source for generating a driving force, and a driving device for controlling the power source in accordance with the guide command and moving the apparatus. The mobile body 10 can be automatically moved according to the guidance instruction by the communication circuit, the power source, and the driving device. The mobile body 10 outputs data of the moving speed of the own apparatus detected by the sensor, for example, every 1 second. The transmission interval of data can be arbitrarily decided.

The positioning device 30 measures the position of each mobile body 10 using the arrival angle of the radio wave received by each receiving antenna 34 of the identification information, and outputs the measured position information. An example of the configuration and processing of the positioning device 30 will be described later.

The arithmetic device 40 checks the movement path of each mobile body 10 with reference to the guide command of each mobile body 10, and predicts the presence or absence of a collision between the mobile bodies. More specifically, the arithmetic device 40 directly or indirectly acquires the guidance instruction of each mobile body 10 generated by the guidance device 20 from the guidance device 20 by using the communication circuit. The arithmetic device 40 acquires data of the moving speed of each mobile body 10 via the positioning device 30. The arithmetic device 40 has an arithmetic circuit mounted with a collision prediction engine constructed using a computer program or constructed by hardware. The collision prediction engine determines coordinates of the passage points of 1 or more moving bodies based on the guidance instruction of each moving body 10, and predicts the presence or absence of a collision between the moving bodies based on the data of the moving speed of each moving body 10. The guidance device 20 receives the prediction result, and reproduces and retransmits the guidance command for the specific mobile object. The "specific mobile object" may be only a plurality of mobile objects for which the occurrence of a collision is predicted, or may be 1 of them. Or may be all moving bodies.

As an example, attention is paid to the moving

bodies

10Y and 10Z in fig. 1. The prediction result of the arithmetic device 40 predicts that the

mobile bodies

10Y and 10Z collide with each other at the illustrated "X" position. When the arithmetic device 40 notifies the guidance device 20 of the prediction result, the guidance device 20 regenerates the guidance command for the mobile body 10Z and transmits the guidance command to the mobile body 10Z. The mobile body 10Z that has received the new guidance instruction moves in accordance with the new guidance instruction. The new guidance instruction includes, for example, an instruction to stop the mobile body 10Z for a fixed time. This prevents the moving

bodies

10Y and 10Z from simultaneously passing through the predicted collision positions, and thus collision can be avoided.

The collision prediction processing of the arithmetic device 40 will be described in more detail.

Fig. 2A shows

guide instructions

110X, 110Y, and 110Z transmitted to the moving

bodies

10X, 10Y, and 10Z, respectively. The k-th position of the moving body 10X is denoted by "PXk", and coordinate values are described later. The k-th position of the moving body 10Y is denoted by "PYk", and the k-th position of the moving body 10Z is denoted by "PZk", and the respective coordinate values are shown. Since each mobile unit 10 transmits and receives data by radio, an SSID (Service Set IDentifier) is shown as an example of information for identifying each mobile unit 10.

The arithmetic device 40 checks whether or not the coordinate values of the passage points of the moving objects 10 are the coordinate values common to the moving objects 10 with reference to the guide commands of the moving objects 10. In the example of fig. 2A, the moving

bodies

10X and 10Y pass through the same position (Xc, Yc) as shown in a block C1 of the guide commands 110X and 110Y. Further, as shown in a block C2 of the

guidance instructions

110Y and 110Z, the moving

bodies

10X and 10Y pass through the same position (Xb-1, Yb + 1).

Fig. 2B shows an example of the movement paths of the moving bodies 10X to 10Z. The moving

bodies

10X and 10Y intersect at the position (Xc, Yc), and 10Y and 10Z intersect at the position (Xb-1, Yb + 1). For convenience, blocks corresponding to blocks C1 and C2 in fig. 2A are shown in the

guide instructions

110X, 110Y, and 110Z, respectively.

Even if a plurality of moving bodies 10 pass through the same position, they do not collide with each other if the passing times are different. Therefore, the arithmetic device 40 further refers to the data of the moving speed of each mobile body 10.

The arithmetic device 40 acquires data of the current moving speeds of the moving

bodies

10Y and 10Z, for example. The arithmetic device 40 calculates the time when the

mobile bodies

10Y and 10Z move while maintaining the respective moving speeds, and reaches the position (Xb-1, Yb + 1). If the difference between the arrival times is smaller than a predetermined threshold value, the arithmetic device 40 predicts that the collision of the

mobile bodies

10Y and 10Z has occurred. On the other hand, if the difference between the arrival times is equal to or greater than the predetermined threshold value, the arithmetic device 40 predicts that the collision of the

mobile bodies

10Y and 10Z does not occur.

The "predetermined threshold" is, for example, 5 seconds.

The arithmetic device 40 notifies the guidance device 20 of the prediction result. The prediction result includes information for identifying each mobile object 10 when the presence or absence of a collision is predicted and the collision is predicted. The arithmetic device 40 may notify the guidance device 20 of the prediction result even when it is predicted that no collision occurs, or may notify the guidance device 20 of the prediction result only when it is predicted that a collision occurs.

When the arithmetic device 40 predicts that a collision between moving bodies occurs, the guidance device 20 generates a new guidance command for each moving body 10 or for each moving body 10 that has collided.

Fig. 3A shows

new guidance instructions

111X, 111Y, and 111Z generated by the guidance device 20. It will be appreciated that the instructions within the various blocks C1 and C2 are not identical and different. Fig. 3B shows an example of the movement paths of the moving bodies 10X to 10Z following a new guidance instruction.

According to the instruction of the block C1, the moving body 10X passes the coordinate value (Xc, Yc), but the moving body 10Y does not pass the different position (Xc-1, Yc). Therefore, collision of the moving

bodies

10X and 10Y in the coordinate values (Xc, Yc) is avoided. For the position (Xc-1, Yc), since the moving body 10X passes first and then the moving body 10Y passes, collision is avoided similarly. In fig. 3B, the direction of the moving object 10Y is changed 2 times at right angles, but this is an example. The advancing direction may be changed by a curved path.

According to the instruction of the block C2, the moving body 10Y passes the coordinate value (Xb-1, Yb +1), but the moving body 10Z passes "Stop: 5sec "reached position Pz1, and stopped for 5 seconds. As a result, the moving

bodies

10Y and 10Z pass through the positions (Xb-1, Yb +1) at different times, and collision of the moving

bodies

10Y and 10Z is avoided.

A stop time of "5 seconds" is an example. The instruction of the stop time may be omitted by setting the stop time to the same value.

In the above example, the arithmetic device 40 predicts whether or not a collision has occurred using the coordinate values of the passage point of each moving body 10 specified in the guide command. However, a collision between moving bodies may occur at a position other than the passage point specified in the guidance instruction. The arithmetic device 40 may approximate a movement path connecting, for example, adjacent 2 passage points by a straight line or a curved line, and obtain coordinate values of each position on the straight line and a passage time thereof. The "positions on the straight line" may be determined, for example, in units of 30cm in consideration of the size of the moving body 10. By obtaining the coordinate values of the passing position and the passing time on the moving path of each moving object 10, it is possible to predict whether or not a collision has occurred with higher accuracy.

When the above-described approximation by a straight line or a curved line is used, the coordinate values may not completely match but may be very close to each other. In order to predict the possibility of collision also in such a case, the distance between a plurality of moving bodies may be used. For example, the arithmetic device 40 may predict that a collision between moving objects occurs when the distance between the moving objects at the same time is smaller than a threshold value. The "threshold" may be determined in consideration of the size of the mobile object 10. The "threshold" may be set to 3 times the size of the mobile object 10, for example.

Hereinafter, for the sake of simplifying the description, an example of processing for determining the presence or absence of collision occurrence using the coordinate values of the passage point indicated in the guidance command will be described.

The configuration of the moving body guide system 1 shown in fig. 1 is an example. A moving body guide system different from the moving body guide system 1 shown in fig. 1 can also be adopted.

Fig. 4 schematically shows the configuration of the moving body guide system 2. The mobile body guide system 2 is different from the mobile body guide system 1 in that a storage device 50 is newly provided in the mobile body guide system 2. By providing the storage device 50, the flow of data transmitted and received by the moving body 10, the guide device 20, the positioning device 30, and the arithmetic device 40 is changed. The flow of the changed data will be described below together with the operation of the storage device 50.

The storage device 50 receives data of the moving speed from each mobile body 10. Upon receiving the data, the storage device 50 stores the data in association with identification information (RFID) of each mobile body 10. The storage device 50 receives a guidance command for each mobile object 10 from the guidance device 20, and stores the guidance command in association with identification information (RFID) of each mobile object 10.

When the storage device 50 stores the guidance command for each mobile body 10, the guidance device 20 transmits a notification indicating that the guidance command is generated to each mobile body 10. Each mobile body 10 that has received the notification transmits an acquisition request of a guidance instruction to the storage device 50.

When the storage device 50 receives a request for acquiring a guide command from each mobile body 10, the guide command of each mobile body 10 is read and transmitted to the mobile body 10 that has transmitted the request. Thereby, a guidance command is distributed to each mobile body 10.

The arithmetic device 40 refers to the guidance instruction and the data of the travel speed stored in the storage device 50, and transmits the prediction result to the storage device 50. The prediction result is also stored in the storage device 50 in association with the identification information (RFID) of each mobile object 10.

The guidance device 20 reads the prediction result stored in the storage device 50, and generates a new guidance command for each mobile body 10 predicted to collide, for example. The boot device 20 transmits the generated new boot instruction to the storage device 50. The storage device 50 overwrites the existing guidance instruction of the corresponding mobile body 10 with the new guidance instruction.

When the storage device 50 stores a new guidance command, the guidance device 20 transmits a notification indicating that the guidance command is updated to the corresponding mobile body 10. Each mobile body 10 that has received the notification transmits an acquisition request of a guidance instruction to the storage device 50.

The storage device 50 transmits a new guidance command to the mobile body 10 that has transmitted the request in response to reception of the acquisition request of the guidance command from the mobile body 10. As a result, a new guidance instruction is distributed to the mobile body 10, and the mobile body 10 can move in accordance with the new guidance instruction.

Next, each component of the moving

body guidance systems

1 and 2 that realize the above-described operation will be described in detail. Next, an AGV is shown as an example of a moving object and will be described.

Fig. 5 is a block diagram showing a configuration of an IC tag 100 mounted on or incorporated in each mobile body 10. The IC tag 100 has an IC51 for generating a high-frequency signal, a storage device 52, and an antenna 54. The storage device 52 is, for example, a flash ROM, and stores unique identification information 53 for each IC tag 100. IC51 periodically transmits identification information using antenna 54. Note that illustration of a battery necessary for the operation of the IC tag 100 is omitted.

In the present embodiment, the IC tag 100 transmits a signal wave according to the bluetooth (registered trademark) low energy (BLE) standard. More specifically, the IC tag 100 continuously transmits a signal wave including an advertisement packet periodically on each channel using 3 channels. The frequency of the signal wave is, for example, a microwave band, but may be a millimeter wave band. The signal waves of the 2.4 gigahertz band can be emitted from the IC tag 100 at intervals of, for example, 10 milliseconds to 200 milliseconds, typically 100 milliseconds. The frequency of the signal wave need not be fixed as long as it can be received by the array antenna 20, and a plurality of frequencies can be hopped.

The advertisement package describes "Public device address" or "Random device address" that functions as identification information (RFID) that uniquely identifies the IC tag 100. This enables the presence of the user to be notified to the surroundings.

In the present embodiment, the IC tag 100 may operate as a so-called "Non-connectable beacon" that broadcasts only an advertisement packet and does not receive a connection request from the positioning apparatus 30 or the like. However, the IC tag 100 may be a "connectable beacon" (capable of receiving a connection request from the positioning apparatus 30 or the like and transmitting and receiving data. The IC tag 100 may operate according to another standard.

Fig. 6 is an external view of an exemplary mobile object 10 according to the present embodiment. Fig. 7 is a block diagram showing a hardware configuration of the mobile unit 10.

The mobile body 10 includes an IC tag 100, a carrier base 111 on which a carrier is placed, a front bumper switch (striker) 14a, a rear bumper switch 14b, a travel control device 17, an IC tag 18, and 4 wheels 11a to 11 d. The bumper switches 14a and 14b are turned on when bumpers provided at the front and rear of the moving body 10 come into contact with an object. The mobile body 10 can detect contact with or collision with another object based on the outputs of the bumper switches 14a and 14 b. The bumper switches 14a and 14b may be provided on the assumption that a collision occurs.

Fig. 6 shows

rear wheels

11a and 11b as driving wheels, a front wheel 11c, and a rear bumper switch 14 b. The front wheels 11d and the front bumper switch 14a are hidden on the back surface of the frame 12.

Refer to fig. 7.

The mobile body 10 further includes a sensor 14c,

motors

15a and 15b, a movement control device 17, and

motor control circuits

58a and 58 b.

The sensor 14c detects the moving speed of the moving body 10. Examples of the sensor 14c are rotor encoders that measure the rotational speeds of the

motors

15a and 15b or the

wheels

11a and 11b, respectively. The

motors

15a and 15b are power sources that generate a propulsive force (driving force) for rotating the

drive wheels

11a and 11b and propelling the moving body 10. The

motor control circuits

58a and 58b are inverter circuits, and control the magnitude of the driving force generated by the

motors

15a and 15 b. The motor control circuit may be referred to as a drive. The mobile body 10 uses electric power stored in a battery, not shown, to operate the

motors

15a and 15 b.

The movement control device 17 includes a microcomputer 55, a memory 56, and a communication circuit 57. The microcomputer 55 is a microcomputer or a computer, and controls the operation of the mobile body 10. The memory 56 expands a computer program executed by the microcomputer 55 and temporarily stores a guidance instruction received from the guidance device 20. Further, the memory 56 is a module including a so-called DRAM, and a flash memory. The flash memory stores, for example, a computer program to be executed by the microcomputer 55 and audio data output from the speaker 18.

The movement control device 17 controls the operation of the mobile body 10. Specifically, the movement control device 17 controls the rotation speed of the

motors

15a and 15b so as to be directed toward the coordinate values indicated by the guide command received from the guide device 20. In addition, the current position of the present apparatus can be notified from the positioning device 30. Further, for example, the current posture (direction) of the device can be acquired from an integrated value from a reference posture by using an output of a gyro sensor (not shown).

The movement control device 17 changes the rotational speed of the

front wheels

11a and 11b by changing the rotational speed of the

motors

15a and 15b, and controls the movement direction of the mobile body 10. For example, the memory 56 holds information on the angle change in the moving direction corresponding to the difference between the rotational speeds of the motor 15a and the motor 15 b. The microcomputer 55 of the movement control device 17 generates and outputs a control signal (PWM signal) for generating a difference between the rotational speeds of the motor 15a and the motor 15b with reference to the information of the angle change.

The microcomputer 55 determines the rotation speeds of the

motors

15a and 15b so as to move the distance indicated by the guidance instruction, and causes the

motors

15a and 15b to rotate the rotation speeds independently. For example, the memory 56 holds information of the movement distance L of 1 rotation of the

drive wheels

11a and 11 b. The microcomputer 55 can calculate the rotation speed of the

drive wheels

11a and 11b by dividing the movement distance L by the distance to the coordinate value indicated by the guide command. The microcomputer 55 outputs a control signal (PWM signal) for rotating the

driving wheels

11a and 11b at the calculated rotation speed. The

motor control circuits

58a and 58b control the current and voltage flowing to the

motors

15a and 15b, respectively, based on a control signal (PWM signal) output from the microcomputer 55 of the movement control device 17 described later, and change the rotational speeds of the motors.

The communication circuit 57 receives the data of the guidance instruction by radio using the data of the moving speed detected by the radio transmission sensor 14 c.

In the mobile body guidance system 2 shown in fig. 4, when a new guidance instruction is stored in the storage device 50, the storage device 50 transmits an update completion notification to the guidance device 20. In response to the reception of the notification, the guidance device 20 transmits a notification indicating that the guidance instruction is updated to the mobile body 10 that is the target of the new guidance instruction. Upon receiving the notification from the guidance device 20, the communication circuit 57 of the mobile unit 10 transmits a request for acquiring a guidance instruction to the storage device 50. The storage device 50 reads out a new guide command of the mobile body 10 that has transmitted the request from the HDD array 68 and transmits the new guide command. This enables the mobile unit 10 to receive the updated new guidance instruction from the storage device 50.

Next, the guide device 20 and the positioning device 30 will be described with reference to fig. 8 and 9.

Fig. 8 shows the configuration of the hardware of the guide device 20.

The guidance device 20 includes a Central Processing Unit (CPU)25, a memory 26, a communication circuit 27, and a map information Database (DB)28, which are connected by an internal bus 29.

The CPU25 is a signal processing circuit that generates a guide command for guiding each mobile body 10 by processing described later. Typically, the CPU25 is a computer formed of a semiconductor integrated circuit. The memory 26 is, for example, a DRAM, and is a work memory used in association with the processing of the CPU 25.

The communication circuit 27 is, for example, a communication circuit having 1 or more communication connectors and performing wired communication of the ethernet (registered trademark) standard. The communication circuit 27 acquires position information indicating the position of each mobile body 10 from the positioning device 30. The communication circuit 27 can also transmit a guidance command to the mobile unit 10 via the receiving antenna 34 of the relay device 32. The communication circuit 27 may transmit a guidance command to each mobile unit 10 via the transmission antenna 33 of the relay device 32. In the example of the mobile body guidance system 2, the guidance device 20 can transmit and receive guidance commands, notifications, and the like to and from the storage device 50.

The map information DB28 holds information such as the layout of the space into which the moving object guidance system 1 is introduced, the area where the moving object 10 can travel, and the detour route.

In the present embodiment, the guide device 20 separately instructs each mobile body 10 to which position to move from an external manager or the like, and stores the instruction in the memory 26. The guidance device 20 refers to the map information DB28 to calculate through which passing points the current position of the mobile object 10 moves to the destination, and generates a guidance instruction.

Fig. 9 shows the configuration of the hardware of the positioning device 30.

The positioning device 30 has a CPU35, a memory 36, and a communication circuit 37, which are connected by an internal bus. The CPU35 measures the position of each IC tag 100, that is, the position of the mobile object 10, by the processing described later, and generates position information indicating the measured position. The memory 26 is, for example, a DRAM, and is a work memory used in association with the processing of the CPU 35. The communication circuit 37 is, for example, a communication circuit having 1 or more communication connectors. The communication circuit 37 is connected to the receiving antenna 34 of the relay device 32 by wire. More specifically, the communication circuit 37 is connected to an output of an antenna element of the antenna element 34a provided in each of the receiving antennas 34, and receives a high-frequency electric signal generated from the electromagnetic wave received by the antenna element 34 a. The communication circuit 37 is connected to the communication circuit 27 of the guidance device 20 via a wired communication line that performs wired communication of the ethernet (registered trademark) standard, for example.

The process (positioning process) of measuring the position of the mobile body 10 by the positioning device 30 will be described below. Various processes for positioning objects in a plane or in space are known. The positioning device 30 measures the position of the mobile body 10 by using one or a combination of a plurality of positioning processes. The following exemplifies the positioning process.

(a) The positioning device 30 measures the Arrival direction Of a radio signal transmitted from the IC tag 100 Of the mobile object 10, and determines the position Of the mobile object (AOA (Angle Of Arrival) method). The AOA system is a system that determines the position of the mobile object 10 by measuring an arrival angle of an arrival radio wave from a reference azimuth (for example, a front direction of a receiving antenna) when a signal transmitted from the IC tag 100 is received by a plurality of receiving antennas 34. The number of base stations (the number of relay devices 32 having receiving antennas 34) required to determine the lowest limit of the location is 2, so the number of relay devices 32 required at the same time needs to be small. Further, since the angle can be accurately measured, there is no obstacle from the base station to the terminal, and the position of the mobile body 10 can be determined with high accuracy when the line of sight is clear.

As the receiving antenna 34, an array antenna in which a plurality of antenna elements are arranged one-dimensionally or two-dimensionally can be used. Alternatively, a phased array antenna may be used which controls the beam direction and radiation pattern by adjusting the phase of the current flowing through each antenna element. In addition, in the case of using an array antenna, the direction of the IC tag 100 with respect to the receiving antenna 34 can be determined by the single receiving antenna 34. In this case, the position of the IC tag 100 can be determined by one receiving antenna 34. For example, when the direction of the IC tag 100 with respect to the receiving antenna 34 arranged on the top surface at a predetermined height is specified, the position of the IC tag 100 can be determined if the height of the IC tag 100 with respect to the ground surface is known or estimated. Therefore, the IC tag 100 can also be positioned by one receiving antenna 34.

(b) The positioning device 30 receives the radio signal transmitted from the IC tag 100 via the plurality Of receiving antennas 34 (or the antenna elements 34a), and determines the position Of the mobile object based on the difference in the reception time in each antenna element 34a (time difference Of Arrival) method. The relay device 32 having the receiving antenna 34 functions as a base station, and must accurately measure the reception time. The relay devices 32 need to synchronize with each other at accurate timing in nanoseconds.

(c) The positioning device 30 determines the position (RSSI (Received Signal strength indication) method) from the Received strength of the radio Signal transmitted from the IC tag 100, using the fact that the position of the receiving antenna 34 is known and the radio wave attenuates according to the distance. However, since the strength of the received signal is affected by multipath, a distance fading model is required for each environment in which the mobile guidance system 1 is introduced in order to calculate the distance (position).

(d) The positioning device 30 may be configured to determine the position of the mobile object 10 based on the position of the camera, the direction in which the camera is directed, and the position of the mobile object 10 in the captured image by capturing an image (for example, a QR code (registered trademark)) to which identification information of the mobile object 10 is added with the camera.

Further, the position measurement accuracy differs depending on the positioning process. In the positioning process (a), the position measurement accuracy is determined by the angular resolution of the antenna and the distance to the object to be measured, and is 10cm in a general building. In the positioning process (c), an error of about 1m may occur even in a case where the conditions are good, for example, several meters in a general room due to a change in the radio wave intensity caused by interference of the radio wave emitted from the IC tag. In the positioning process (d), the positioning error depends on the number of pixels of the image sensor, the spatial resolution, and the deformation based on the lens. In addition, a relatively high load process such as object recognition is required.

From the viewpoint of accuracy, the above-described positioning process (a) is excellent at the present time. However, the moving

body guide systems

1, 2 of the present disclosure may also be constructed using any of the positioning processes (b) to (d).

Fig. 10 shows a hardware configuration of the arithmetic device 40. The arithmetic device 40 includes a CPU45, a memory 46, and a communication circuit 47, which are connected by an internal bus.

The CPU45 is an arithmetic circuit that controls the operation of the arithmetic device 40. The memory 46 is, for example, a DRAM, and is a work memory used in association with the processing of the CPU 45. For example, the CPU45 reads and executes a computer program (basic software) of an Operating System (OS) from the memory 46, and also reads and executes a computer program (application software) that predicts a collision between moving bodies, which is executed on the OS, from the memory 46. A collision prediction processing system built using application software may be referred to as a "collision prediction engine". The "collision prediction engine" may also be implemented as a hardware-based arithmetic circuit using one or more semiconductor integrated circuits. The collision prediction engine implements the processing described later.

The communication circuit 47 is, for example, a communication circuit having 1 or more communication connectors and performing wired communication of the ethernet (registered trademark) standard. In the mobile body guidance system 1, the communication circuit 47 receives a guidance instruction from the guidance device 20. In the

mobile guidance system

2, 47 transmits and receives data to and from the storage device 50.

Fig. 11 shows the configuration of the hardware of the storage device 50. The storage device 50 may also be referred to as a file server device. As described above, the storage device 50 is provided in the mobile body guidance system 2.

The storage device 50 has a CPU65, a memory 66, a communication circuit 67, and an HDD array 68, which are connected by an internal bus.

The CPU65 controls the operation of the storage device 50. The memory 66 is, for example, a DRAM, and is a work memory used in association with processing of the CPU 65. For example, the CPU65 reads and executes a computer program (basic software) of an Operating System (OS) from the memory 66, and reads and executes a server program (application software) executed on the OS from the memory 66. As a result, the processing described later is realized.

The communication circuit 67 is, for example, a communication circuit having 1 or more communication connectors and performing wired communication of the ethernet (registered trademark) standard. The communication circuit 67 receives a boot instruction from the boot device 20 and stores it in the HDD array 68. The communication circuit 67 receives a request for acquiring a guidance command from the mobile unit 10, and transmits the requested guidance command to the mobile unit 10 via the transmission antenna 33 of the relay device 32.

The HDD array 68 is a collection of a plurality of Hard Disk Drives (HDDs). The HDD array 68 has a sufficient recording area for storing various data such as identification information and moving speed data transmitted from each mobile body 10, a guidance instruction transmitted from the guidance device 20, and a prediction result of the arithmetic device 40. A Solid State Drive (SSD) can also be utilized instead of the HDD.

Next, the operations of the mobile body 10, the guide device 20, and the positioning device 30 performed in the mobile body guide system 1 will be described with reference to fig. 12.

Fig. 12 shows communication performed in the mobile body guidance system 1, and a processing procedure of the mobile body 10, the guidance device 20, the positioning device 30, and the arithmetic device 40.

In the following description, the main bodies of the operations are the mobile body 10, the guide device 20, the positioning device 30, and the arithmetic device 40, but actually, the microcomputer 55 of the mobile body 10, the CPU25 of the guide device 20, the CPU35 of the positioning device 30, and the CPU45 of the arithmetic device 40 are main bodies and transmit and receive information via the respective communication circuits. The time flows from the upper side of the drawing to the lower side.

In step S201, the positioning device 30 receives the RFID from the IC tag 100, and measures the position of the IC tag 100, that is, the position of the mobile object 10, by the above-described 1 or more positioning processes. The positioning device 30 transmits the measurement result to the guide device 20.

In step S301, the guidance device 20 acquires position information of the mobile body 10 from the positioning device 30, and generates a guidance command based on the position of the mobile body.

When the mobile body 10 transmits the data of the moving speed in step S101, the arithmetic device 40 receives the data in step S401.

The sequence of step S101 and step S201 is an example. The order may also be changed. In addition, the timing at which step S301 is executed is arbitrary as long as it is after step S201.

In step S302, the guidance device 20 transmits the generated guidance command to each of the mobile body 10 and the arithmetic device 40.

In step S102, the mobile body 10 receives a guidance instruction. Thereby, the mobile body 10 can start moving in response to the guidance command. However, in the present embodiment, the mobile body 10 remains moving until a fixed time elapses. The reason is that there is a possibility that a new guidance instruction is issued by the guidance device 20 based on the prediction result of the arithmetic device 40. The "fixed time" may be set longer than the total value of the longest time required for the arithmetic unit 40 to perform the prediction processing, the longest time required for the guidance device 20 to perform the processing for regenerating the guidance command, and the longest allowable communication delay time, for example.

In step S402, the arithmetic device 40 receives a guidance instruction. In the present embodiment, the arithmetic device 40 receives a guidance command for all moving objects from the guidance device 20. However, when a plurality of moving objects exist in different regions where collision cannot occur, guidance commands for all the moving objects in the common region may be received.

In step S403, the arithmetic device 40 determines the coordinates of the passage point of each of the moving bodies specified by the guide command, and predicts whether or not a collision between the moving bodies occurs based on the data of each of the moving speeds. The contents of the processing are as described with reference to fig. 3A and 3B. In step S404, the arithmetic device 40 transmits the prediction result to the guidance device 20.

In step S303, the guidance device 20 receives the prediction result.

In step S304, the guidance device 20 determines whether the prediction result indicates the occurrence of a collision. If the prediction result indicates the occurrence of a collision, the process proceeds to step S305. On the other hand, if the prediction result does not indicate the occurrence of a collision, the process ends. When a fixed time has elapsed from the end of the processing, the mobile body 10 starts moving in accordance with the guidance instruction received in step S102.

In step S305, the guidance device 20 generates a new guidance instruction and transmits the new guidance instruction to the mobile body 10. The mobile body 10 starts moving in accordance with the received new guidance instruction. The arithmetic unit 40 also receives a newly generated guidance command and predicts whether or not a collision occurs again.

The vertical processing shown in fig. 12, for example, the processing from step S101 to step S103 of the mobile body 10 is performed by the microcomputer 55 of the mobile body 10, the CPU25 of the guidance device 20, the CPU35 of the positioning device 30, and the CPU45 of the arithmetic device 40, and can be regarded as a flowchart. These processes may be implemented as a computer program comprising a plurality of commands. The computer programs are developed in the respective memories and executed.

Note that the communication performed in the mobile body guidance system 2 (fig. 4) and the order of processing of each component are not described. The processing performed in the moving object guide system 2 is different from the processing shown in fig. 12 in that the storage device 50 is interposed. However, the flow of the process of the mobile body guidance system 2 will be clear to those skilled in the art when the description of fig. 12 and the description of fig. 4 are combined.

In the present disclosure, the guide device 20 and the positioning device 30 are explained as separate devices. However, the guide means 20 and the positioning means 30 may also be integrated. For example, the guidance device 20 may have a function equivalent to that of the positioning device 30, and measure positional information of the moving object to generate the guidance command. In this case, the guide device 20 is connected to the receiving antenna 34, and the CPU25 of the guide device 20 performs positioning processing.

However, the reason why such two-dimensional specification is adopted is mainly because the present specification assumes that the position of a moving body traveling on a floor surface of a factory is specified.

However, the coordinate values of the positions can also be specified three-dimensionally. For example, when the mobile object operates in a facility having a plurality of floors, information for specifying a floor may be further added to the guidance instruction.

In the mobile body guidance system 2, the guidance device 20 and the storage device 50 have been described as separate devices. This is because the load distribution is achieved by causing the guide device 20 to perform the process of generating and changing the guide command and causing the storage device 50 to transmit and receive the guide command to and from the mobile body 10. However, the guide device 20 and the storage device 50 may be integrated. For example, fig. 13 shows a configuration example in which the guide device 20 and the HDD array 68 of the storage device 50 are housed in one housing. With the configuration of fig. 13, the transmission and reception of the changed guidance instruction between the guidance device 20 and the storage device 50 are completed in the guidance device 20, and it is not necessary to transmit and receive the update completion notification.

In this specification, an example in which various communications are performed between a mobile object and a transmission antenna and a reception antenna is described. The frequency of the electromagnetic wave or the ultrasonic wave used for positioning, the frequency used for communication used for transmitting the traveling condition, and the frequency used for communication for receiving the guidance instruction may be the same, or 2 or 3 or more different frequencies. The same is true for the communication method. For example, the positioning process (a) may use electromagnetic waves of a frequency of BLE (Bluetooth low energy) standard. The transmission of the running condition and the reception of the guidance command may use electromagnetic waves of a frequency in the Bluetooth (registered trademark) standard, or a frequency in the 2.4GHz band or the 5GHz band in the Wi-Fi (registered trademark) standard.

In the above-described embodiment, the sensor 14c of the mobile body 10 detects the moving speed of the mobile body 10, but the moving speed can be detected without providing the sensor 14c in each mobile body 10. Specifically, the positioning device 30 may measure the amount of change in the position of each mobile body 10 per unit time to determine the moving speed. The arithmetic unit 40 may receive the data of the moving speed from the positioning device 30 and perform the above-described processing.

Industrial applicability of the invention

The moving body guide system of the present disclosure can be widely used for controlling the position of a moving body.

Description of the symbols

1. 2 mobile body guidance system, 10 mobile body, 20 guidance device, 25CPU, 26 memory, 27 communication circuit, 28 map information Database (DB), 30 positioning device, 32 relay device, 40 arithmetic device, 50 storage device.

Claims

1. A moving body guidance system that guides each of a plurality of moving bodies,

the mobile body guidance system includes:

a plurality of moving bodies;

a positioning device that measures a position of each of the moving bodies and outputs position information of each of the moving bodies;

a guidance device that generates a guidance command for guiding each of the moving bodies for each of the moving bodies; and

a computing device for confirming the moving path of each moving body by referring to the guiding command of each moving body and predicting whether collision between the moving bodies occurs or not,

each of the moving bodies includes:

a sensor that detects a moving speed of the moving body;

a first communication circuit that receives the guidance command and transmits data of the movement speed;

a power source that generates a driving force; and

a drive device for controlling the power source according to the guide command and moving the movable body,

the guide device includes:

a signal processing circuit that generates the guidance instruction; and

a second communication circuit for communicating with each of the mobile units,

the arithmetic device includes:

a third communication circuit that receives the guidance command and the data of the moving speed of each of the moving objects; and

an arithmetic circuit for determining coordinates of a passing point of at least one of the moving bodies based on the guide command for each of the moving bodies, and predicting whether or not a collision between the moving bodies occurs based on the data of the moving speed,

the guide device performs the following control:

generating the guide command for specifying a movement path of each of the moving objects;

transmitting the guidance instruction to each of the moving bodies;

generating a new guidance command for each of the moving objects when the collision between the moving objects is predicted by the arithmetic circuit of the arithmetic device; and

the guidance instruction is transmitted to each of the mobile bodies,

the moving bodies move in accordance with the received new guidance instruction.

2. The moving body guide system according to claim 1,

the arithmetic circuit of the arithmetic device predicts an arrival time of each mobile body at a passage point based on the data of the moving speed of each mobile body and predicts whether or not a collision between the mobile bodies occurs.

3. The moving body guide system according to claim 1 or 2,

when the distance between the plurality of moving bodies at the same time is smaller than the threshold value, the arithmetic circuit of the arithmetic device predicts that a collision between the moving bodies occurs.

4. The moving body guide system according to any one of claims 1 to 3,

the new guidance instruction includes at least one of an instruction to change a movement route after the passage point and an instruction to stop the movement.

5. The moving body guide system according to claim 4,

when the new guidance instruction includes an instruction to stop the movement, the instruction further includes an instruction to stop the movement.

6. The moving body guide system according to any one of claims 1 to 5,

the mobile body guidance system further includes a storage device for storing a guidance instruction for each mobile body,

the arithmetic device acquires a guidance instruction for each of the moving objects from the storage device.

7. The moving body guide system according to claim 6,

the storage device also stores data of the moving speed of each moving body,

the arithmetic device acquires data of the moving speed of each of the moving bodies from the storage device.