WO2022049743A1

WO2022049743A1 - Travel control method for autonomous carrier vehicle, autonomous carrier vehicle, and conveyance system

Info

Publication number: WO2022049743A1
Application number: PCT/JP2020/033689
Authority: WO
Inventors: 健太水井
Original assignee: ヤマハ発動機株式会社
Priority date: 2020-09-04
Filing date: 2020-09-04
Publication date: 2022-03-10
Also published as: JPWO2022049743A1; DE112020007392T5

Abstract

This travel control method for an autonomous carrier vehicle (20) is for controlling traveling of an autonomous carrier vehicle that autonomously travels while towing a carriage (30), said method comprising: a step for acquiring a state of the carriage; a step for detecting a relative attitude of the carriage with respect to a carrier vehicle body (27) on the basis of the state of the carriage; and a step for controlling traveling speed of the carrier vehicle body on the basis of the relative attitude of the carriage with respect to the carrier vehicle body.

Description

Driving control method for autonomous transport vehicles, autonomous transport vehicles and transport systems

The present invention relates to a traveling control method for an autonomous transport vehicle, an autonomous transport vehicle and a transport system, and more particularly to a travel control method for an autonomous transport vehicle that tow a carriage and autonomously travels, an autonomous transport vehicle and a transport system thereof. ..

Conventionally, an autonomous transport vehicle that tows a dolly and runs autonomously is known. Such a method is disclosed, for example, in Japanese Patent No. 6362418.

The above-mentioned Japanese Patent No. 6362418 discloses an autonomous transport vehicle that tows a trolley and autonomously travels. This autonomous carrier is configured to efficiently travel at bends such as corners by disconnecting the bogie and reconnecting it with the bogie when traveling at bends such as corners. There is.

Japanese Patent No. 6362418

However, in the autonomous transport vehicle described in Japanese Patent No. 6362418, since the bogie is disconnected and reconnected at the bent portion such as a corner, it takes time to move the bent portion and is manufactured. When used in factories, there is the inconvenience of reduced productivity. Therefore, it is conceivable to drive the vehicle at the bent portion while towing the bogie by the autonomous transport vehicle without separating the autonomous transport vehicle and the bogie.

However, in this case, when the autonomous transport vehicle in the state of towing the bogie travels at the bent point at the same high running speed as when the bogie is not towed, the bogie shakes greatly at the bent point and the bogie falls. there is a possibility. Therefore, when towing the bogie by the autonomous carrier, it is conceivable that the traveling speed of the autonomous carrier is uniformly reduced.

However, in this case, while it is possible to suppress the overturning of the bogie at the bent point, the productivity is lowered due to the decrease in the traveling speed of the autonomous carrier. For this reason, there is a problem that it is difficult to increase productivity while suppressing the overturning of the bogie at the bending point when towing the bogie by the autonomous transport vehicle (transport vehicle main body).

The present invention has been made to solve the above-mentioned problems, and one object of the present invention is to produce the bogie while suppressing the overturning of the bogie at a bending point when the bogie is towed by the main body of the transport vehicle. It is to provide a traveling control method of an autonomous transport vehicle, an autonomous transport vehicle, and a transport system capable of enhancing the productivity.

The travel control method of the autonomous transport vehicle according to the first aspect of the present invention is a travel control method of the autonomous transport vehicle that tows the carriage and autonomously travels, and is a step of acquiring the state of the carriage and the state of the carriage. Based on the above, a step of detecting the relative posture of the bogie with respect to the main body of the transport vehicle and a step of controlling the traveling speed of the main body of the transport vehicle based on the relative posture of the bogie with respect to the main body of the transport vehicle are provided.

In the traveling control method of the autonomous carrier according to the first aspect of the present invention, as described above, the step of detecting the relative posture of the carriage with respect to the carrier body based on the state of the carriage and the carriage with respect to the carrier body A step for controlling the traveling speed of the main body of the transport vehicle based on the relative posture is provided. As a result, when a change in the relative posture of the bogie with respect to the transport vehicle body occurs when moving a bent part such as a corner, the traveling speed of the transport vehicle body is appropriately adjusted according to the change in the relative posture of the bogie with respect to the transport vehicle body. Can be changed. As a result, unlike the case where the traveling speed of the transport vehicle body is uniformly reduced when the carriage is towed by the transport vehicle body, an unnecessary decrease in the traveling speed does not occur. As a result, when the bogie is towed by the main body of the transport vehicle, it is possible to increase the productivity while suppressing the bogie from tipping over at the bending point. Further, when an abnormality occurs in the posture of the carriage when the carriage is towed by the carrier body, the traveling speed of the carrier body can be appropriately changed. This also makes it possible to prevent the trolley from tipping over when the trolley is towed by the transport vehicle main body.

In the traveling control method of the autonomous transport vehicle according to the first aspect, preferably, the step of acquiring the state of the bogie includes the step of acquiring the state of the characteristic point of the bogie, and the relative posture of the bogie with respect to the main body of the transport vehicle is determined. The detection step includes a step of detecting the relative posture of the bogie with respect to the carrier main body based on the state of the feature points of the bogie. With this configuration, the relative posture of the carriage with respect to the main body of the carriage can be easily detected by simply acquiring the state of the feature points of the carriage. Further, since it is not necessary to provide the bogie with a sensor or the like for detecting the posture, it is possible to detect the relative posture of the bogie while making the bogie a simple structure.

In this case, preferably, the feature point of the dolly includes a marker provided on the dolly. With this configuration, unlike the case where the shape of the corners of the bogie is used as a feature point, it is possible to detect the relative posture of the bogie with respect to the main body of the transport vehicle by using a dedicated marker. As a result, the relative posture of the bogie with respect to the main body of the transport vehicle can be accurately detected.

In the traveling control method of the autonomous transport vehicle according to the first aspect, preferably, the relative posture of the carriage with respect to the transport vehicle body includes information on the inclination angle of the carriage with respect to the transport vehicle body, and controls the travel speed of the transport vehicle body. The step to be performed includes a step of controlling the traveling speed of the transport vehicle main body based on the information of the inclination angle of the bogie with respect to the transport vehicle main body. With this configuration, the traveling speed of the transport vehicle body can be accurately controlled based on the information on the inclination angle of the bogie with respect to the transport vehicle body.

In this case, preferably, the step of controlling the traveling speed of the transport vehicle body is the traveling speed of the transport vehicle body so that the transport vehicle body decelerates based on the information of the inclination angle of the carriage with respect to the transport vehicle body in the horizontal plane. Includes steps to control. With this configuration, when the tilt angle of the bogie with respect to the transport vehicle body in the horizontal plane changes when the bending point such as a corner is moved, the tilt angle of the bogie with respect to the transport vehicle main body in the horizontal plane changes. Therefore, the traveling speed of the transport vehicle body can be appropriately reduced. As a result, the traveling speed of the transport vehicle main body can be accurately controlled when the bent portion is moved.

In the configuration in which the relative posture of the carriage with respect to the carrier body includes information on the inclination angle of the carriage with respect to the carrier body, preferably, the step of controlling the traveling speed of the carrier body is the step of controlling the traveling speed of the carriage with respect to the carrier body in the vertical plane. It includes a step of controlling the traveling speed of the transport vehicle body so that the transport vehicle body stops based on the information of the inclination angle. With this configuration, for example, when an abnormality occurs in the posture of the bogie due to an abnormality in the wheels of the bogie, and the tilt angle of the bogie with respect to the bogie body in the vertical plane changes, the bogie body can be moved. It can be stopped. As a result, it is possible to prevent the bogie from tipping over when the bogie is towed by the transport vehicle main body.

In this case, preferably, a step of acquiring information on the tilt angle of the transport vehicle body in the vertical plane is further provided, and a step of controlling the traveling speed of the transport vehicle main body is a step of tilting the carriage with respect to the transport vehicle main body in the vertical plane. Including a step of controlling the traveling speed of the transport vehicle body so that the transport vehicle body stops based on the information of the above and the information of the inclination angle of the transport vehicle body in the vertical plane. With this configuration, it is possible to control to stop the transport vehicle body based not only on the tilt angle of the carriage with respect to the transport vehicle body in the vertical plane but also on the tilt angle of the transport vehicle body in the vertical plane. .. As a result, it is possible to accurately control the stop of the transport vehicle main body.

In the traveling control method of the autonomous transport vehicle according to the first aspect, preferably, the step of controlling the traveling speed of the transport vehicle main body is at least one of the shape of the carriage, the weight of the carriage, and the position of the center of gravity of the carriage. In consideration of this, a step of controlling the traveling speed of the main body of the transport vehicle is included. With this configuration, the traveling speed of the transport vehicle body can be controlled in consideration of at least one of the shape of the carriage, the weight of the carriage, and the position of the center of gravity of the carriage, which differ depending on the type of the carriage. As a result, the traveling speed of the transport vehicle main body can be appropriately controlled according to the type of the carriage.

In the traveling control method of the autonomous transport vehicle according to the first aspect, preferably, the transport vehicle main body or the carriage includes a connecting portion connecting the transport vehicle main body and the carriage, and the transport vehicle main body drives the connecting portion. It further includes a step of controlling the relative posture of the bogie with respect to the transport vehicle main body in the horizontal plane by driving the connecting portion by the drive unit when the bogie is towed by the transport vehicle main body including the drive unit. With this configuration, the transport vehicle body can be driven while controlling the relative posture of the carriage with respect to the transport vehicle body in the horizontal plane. As a result, the running stability of the transport vehicle body can be improved as compared with the case where the relative posture of the carriage with respect to the transport vehicle body in the horizontal plane cannot be controlled.

In this case, preferably, the step of controlling the relative posture of the bogie with respect to the transport vehicle body in the horizontal plane is such that the movement of the bogie due to inertia is canceled by driving the connecting portion by the drive unit when the transport vehicle body turns. , Including the step of controlling the relative posture of the bogie with respect to the main body of the carrier in the horizontal plane. With this configuration, it is possible to prevent the carriage from moving so as to be shaken by inertia when the transport vehicle body is turned. As a result, the dolly can be moved compactly when the main body of the transport vehicle turns. As a result, it is possible to easily perform a running operation such as turning and turning in a narrow bent portion.

In the configuration in which the transport vehicle main body includes a drive unit for driving the connecting portion, the transport vehicle main body preferably further includes a stopper that restricts the movement of the connecting portion, and controls the relative posture of the carriage with respect to the transport vehicle main body in a horizontal plane. The step to be performed includes a step of controlling the relative posture of the carriage with respect to the transport vehicle main body in the horizontal plane by driving the connecting portion by the driving portion within the angle range limited by the stopper. With this configuration, the connecting portion can be driven so as not to come into contact with the stopper when the connecting portion is driven by the driving unit. As a result, it is possible to prevent a load from being applied to both the connecting portion and the stopper due to the contact between the connecting portion and the stopper when the connecting portion is driven by the driving portion. Further, by providing a stopper, the movement of the connecting portion can be restricted. As a result, by limiting the movement of the connecting portion, the movement of the dolly can be restricted to a predetermined range.

In the traveling control method of the autonomous transport vehicle according to the first aspect, preferably, the step of controlling the traveling speed of the transport vehicle main body is the relative posture of the carriage with respect to the transport vehicle main body by controlling the traveling speed of the transport vehicle main body. It includes a step of acquiring the correction time required for the correction and a step of detecting an abnormality in running based on the comparison between the correction time and the reference correction time. With this configuration, it is possible to detect a running abnormality caused by an abnormality such as an abnormality on the floor surface and an abnormality on the wheels of the bogie. As a result, when a running abnormality is detected, the running abnormality can be quickly resolved.

In this case, preferably, the step of controlling the traveling speed of the transport vehicle main body further includes a step of learning the reference correction time based on the correction time. With this configuration, the reference correction time can be updated by learning. As a result, the updated reference correction time makes it possible to detect running abnormalities more accurately.

In the configuration for learning the reference correction time, preferably, the step for learning the reference correction time is the relative posture of the carriage with respect to the transport vehicle body, the traveling speed of the transport vehicle body, the weight of the carriage, or the traveling direction of the transport vehicle body. Each includes a step of learning the reference correction time. With this configuration, the reference correction time can be learned for each case. As a result, it is possible to detect running abnormalities with higher accuracy according to each case by the reference correction time divided into cases.

In the traveling control method of the autonomous transport vehicle according to the first aspect, preferably, when the transport vehicle main body and the carriage are connected, the step of moving the transport vehicle main body to the connection position with the carriage is performed based on the state of the carriage. Further prepare. With this configuration, the transport vehicle body and the carriage can be automatically connected. As a result, it is possible to automate from the connection between the transport vehicle main body and the bogie to the towing running of the bogie by the transport vehicle main body.

The autonomous transport vehicle according to the second aspect of the present invention is an autonomous transport vehicle that pulls the bogie and autonomously travels, and is a state acquisition unit that acquires the state of the bogie and a bogie acquired by the state acquisition unit. It is provided with a control unit that detects the relative posture of the bogie with respect to the main body of the transport vehicle based on the state and controls the traveling speed of the main body of the transport vehicle based on the relative posture of the bogie with respect to the main body of the transport vehicle.

In the autonomous transport vehicle according to the second aspect of the present invention, as described above, based on the state of the bogie acquired by the state acquisition unit, the relative posture of the bogie with respect to the transport vehicle main body is detected and the relative posture of the bogie with respect to the transport vehicle main body is detected. A control unit for controlling the traveling speed of the main body of the transport vehicle is provided based on the relative posture of the bogie. As a result, when a change in the relative posture of the bogie with respect to the transport vehicle body occurs when moving a bent part such as a corner, the traveling speed of the transport vehicle body is appropriately adjusted according to the change in the relative posture of the bogie with respect to the transport vehicle body. Can be changed. As a result, unlike the case where the traveling speed of the transport vehicle body is uniformly reduced when the carriage is towed by the transport vehicle body, an unnecessary decrease in the traveling speed does not occur. As a result, it is possible to provide an autonomous transport vehicle capable of increasing productivity while suppressing the bogie from tipping over at a bending point when the bogie is towed by the transport vehicle main body. In addition, when an abnormality occurs in the posture of the bogie when the bogie is towed by the main body of the transport vehicle, the traveling speed of the main body of the transport vehicle is increased according to the change in the relative posture of the bogie with respect to the main body of the transport vehicle due to the abnormal posture of the bogie. It can also be changed appropriately. This also makes it possible to prevent the trolley from tipping over when the trolley is towed by the transport vehicle main body.

In the autonomous transport vehicle according to the second aspect, preferably, the state acquisition unit is configured to acquire the state of the feature point of the bogie, and the control unit is the feature of the bogie acquired by the state acquisition unit. It is configured to detect the relative posture of the bogie with respect to the main body of the transport vehicle based on the state of the points. With this configuration, the relative posture of the carriage with respect to the main body of the carriage can be easily detected by simply acquiring the state of the feature points of the carriage. Further, since it is not necessary to provide the bogie with a sensor or the like for detecting the posture, it is possible to detect the relative posture of the bogie while making the bogie a simple structure.

The transport system according to the third aspect of the present invention includes a trolley, an autonomous transport vehicle that pulls the trolley and autonomously travels, and a control device that transmits a command to the autonomous transport vehicle. Based on the state acquisition unit that acquires the state of the trolley and the state of the trolley acquired by the state acquisition unit, the relative posture of the trolley with respect to the transport vehicle body is detected, and the relative posture of the trolley with respect to the transport vehicle body is used. , A transport vehicle control unit that controls the traveling speed of the transport vehicle main body, and the like.

In the transport system according to the third aspect of the present invention, as described above, the relative posture of the carriage with respect to the transport vehicle body is detected based on the state of the carriage acquired by the state acquisition unit, and the carriage with respect to the transport vehicle body is detected. A transport vehicle control unit that controls the traveling speed of the transport vehicle main body based on the relative posture is provided. As a result, when a change in the relative posture of the bogie with respect to the transport vehicle body occurs when moving a bent part such as a corner, the traveling speed of the transport vehicle body is appropriately adjusted according to the change in the relative posture of the bogie with respect to the transport vehicle body. Can be changed. As a result, unlike the case where the traveling speed of the transport vehicle body is uniformly reduced when the carriage is towed by the transport vehicle body, an unnecessary decrease in the traveling speed does not occur. This makes it possible to provide a transport system capable of increasing productivity while suppressing the bogie from tipping over at a bent point when the bogie is towed by the transport vehicle main body. In addition, when an abnormality occurs in the posture of the bogie when the bogie is towed by the main body of the transport vehicle, the traveling speed of the main body of the transport vehicle is increased according to the change in the relative posture of the bogie with respect to the main body of the transport vehicle due to the abnormal posture of the bogie. It can also be changed appropriately. This also makes it possible to prevent the trolley from tipping over when the trolley is towed by the transport vehicle main body.

In the transport system according to the third aspect, preferably, the state acquisition unit is configured to acquire the state of the feature point of the bogie, and the transport vehicle control unit is the feature of the bogie acquired by the state acquisition unit. It is configured to detect the relative posture of the bogie with respect to the main body of the transport vehicle based on the state of the points. With this configuration, the relative posture of the carriage with respect to the main body of the carriage can be easily detected by simply acquiring the state of the feature points of the carriage. Further, since it is not necessary to provide the bogie with a sensor or the like for detecting the posture, it is possible to detect the relative posture of the bogie while making the bogie a simple structure.

According to the present invention, as described above, when the bogie is towed by the main body of the transport vehicle, a traveling control method for an autonomous transport vehicle capable of increasing productivity while suppressing the bogie from tipping over at a bending point is autonomous. A type transfer vehicle and a transfer system can be provided.

It is a block diagram which shows the transport system by one Embodiment. It is a block diagram which shows the server by one Embodiment. It is a block diagram which shows the autonomous transport vehicle by one Embodiment. It is a schematic diagram which shows the characteristic point of the bogie according to one Embodiment. It is a schematic diagram for demonstrating the acquisition of the state of the characteristic point of a carriage by one Embodiment. It is a schematic diagram for demonstrating the state which the dolly is towed straight, the state which the dolly is tilted and towed in a horizontal plane, and the state which the dolly is tilted and towed in a circular plane according to one embodiment. .. It is a schematic diagram for demonstrating the drive control of the connection part by one Embodiment. It is a schematic diagram for demonstrating the correction time at the time of traveling speed control by one Embodiment. It is a schematic diagram for demonstrating the area at the time of traveling speed control by one Embodiment. It is a figure for demonstrating the automatic connection control of an autonomous transport vehicle by one Embodiment. It is a flowchart for demonstrating the automatic connection processing of the autonomous transport vehicle by one Embodiment. It is a flowchart for demonstrating the speed control process of the autonomous transport vehicle by one Embodiment. It is a continuation flowchart of FIG. It is a flowchart for demonstrating the traveling stop processing of an autonomous transport vehicle by one Embodiment. It is a flowchart for demonstrating the connection part control process of the autonomous transport vehicle by one Embodiment. It is a schematic diagram for demonstrating the acquisition of the state of the characteristic point of a bogie by the modification of one Embodiment.

Hereinafter, embodiments embodying the present invention will be described with reference to the drawings.

(Configuration of board manufacturing system)
The configuration of the transport system 100 according to the embodiment of the present invention will be described with reference to FIG.

The transfer system 100 according to this embodiment is a system used in a manufacturing factory. The manufacturing factory in which the transfer system 100 is used is not particularly limited, but may be, for example, a substrate manufacturing factory that manufactures a substrate by mounting an electronic component on a printed circuit board. As shown in FIG. 1, the transport system 100 includes a server 10, an autonomous transport vehicle 20, and a carriage 30. In addition, although the autonomous transport vehicle 20 and the trolley 30 are shown one by one in FIG. 1, in an actual manufacturing factory, a plurality of autonomous transport vehicles 20 and trolleys 30 are provided. Further, the server 10 is an example of a "control device" in the claims.

(Server configuration)
As shown in FIG. 1, the server 10 is configured to transmit a command to the autonomous carrier 20. The server 10 is composed of, for example, a personal computer. As shown in FIG. 2, the server 10 includes a control unit 11, a storage unit 12, a display unit 13, an operation unit 14, and a communication unit 15.

The control unit 11 is a control circuit that controls each unit of the server 10. The control unit 11 includes a CPU (Central Processing Unit) and a memory. The control unit 11 is configured to control transmission of a command to the autonomous carrier 20 based on a manufacturing plan, user input, and the like. The storage unit 12 includes a rewritable storage medium such as a flash memory, and is configured to be able to store various types of information. The storage unit 12 stores information on the manufacturing plan, information on the autonomous transport vehicle 20, information on the trolley 30, and the like.

The display unit 13 includes, for example, a liquid crystal display unit, and is configured to be capable of displaying various types of information. The operation unit 14 includes an input unit such as a mouse and a keyboard, and is configured to be able to accept user input operations. The communication unit 15 is configured to be able to send and receive information to and from the autonomous carrier 20. The communication unit 15 is a wireless communication unit for wireless communication. The server 10 is communicably connected to the autonomous carrier 20 via a network.

(Configuration of autonomous transport vehicle)
Next, the configuration of the autonomous transport vehicle 20 will be described.

The autonomous transport vehicle 20 is configured to tow the carriage 30 to autonomously travel. Specifically, the autonomous transport vehicle 20 is configured to transport articles used in a manufacturing factory by towing a carriage 30 and autonomously traveling.

As shown in FIGS. 3 and 4, the autonomous transport vehicle 20 includes a plurality of (four) drive wheels 20a, a plurality of (four) drive wheel motors 20b, a drive wheel control unit 20c, and a connecting unit 20d. And a connecting portion motor 20e, and a pair of stoppers 20f. Further, the autonomous transport vehicle 20 includes a control unit 21, an image pickup unit 22, a communication unit 23, a battery 24, a tilt sensor 25, and a storage unit 26. These configurations are provided in the transport vehicle main body 27. In FIG. 3, for convenience, a plurality (4) drive wheels 20a and a plurality (4) drive wheel motors 20b are shown one by one. Further, the control unit 21 is an example of the "transport vehicle control unit" in the claims. Further, the connecting unit motor 20e is an example of the "driving unit" in the claims. Further, the image pickup unit 22 is an example of the "state acquisition unit" in the claims.

The plurality of drive wheels 20a are configured to drive the transport vehicle main body 27. The plurality of drive wheels 20a are configured so that the transport vehicle main body 27 can travel straight or turn. Two driving wheels 20a are provided on each of the left and right sides of the transport vehicle main body 27. The plurality of drive wheel motors 20b are configured to drive the plurality of drive wheels 20a. The plurality of drive wheel motors 20b are provided so as to correspond to the plurality of drive wheels 20a. The drive wheel control unit 20c is configured to control a plurality of drive wheel motors 20b based on a command from the control unit 21 to control the traveling direction and traveling speed of the transport vehicle main body 27 by the plurality of driving wheels 20a. Has been done.

The connecting portion 20d is a connecting member that connects the transport vehicle main body 27 and the carriage 30. The connecting portion 20d is configured to connect the transport vehicle body 27 and the carriage 30 so as to be rotatable around the rotation axis C extending in the vertical direction (Z direction) with the connection point on the transport vehicle body 27 side as the center of rotation. ing. The connecting portion motor 20e is configured to drive the connecting portion 20d. The connecting portion motor 20e is configured to rotate the connecting portion 20d around the rotation axis C based on a command from the control unit 21. The pair of stoppers 20f are configured to limit the movement of the connecting portion 20d. The pair of stoppers 20f are provided on both sides of the connecting portion 20d. The pair of stoppers 20f are provided in a V shape with the connecting portion 20d interposed therebetween.

The control unit 21 is configured to control each unit of the autonomous transport vehicle 20. The control unit 21 includes a CPU (Central Processing Unit) and a memory. The control unit 21 is configured to control the drive wheel motor 20b via the drive wheel control unit 20c to control the autonomous traveling of the autonomous transport vehicle 20.

Further, the control unit 21 is configured to autonomously drive the autonomous transport vehicle 20 to the destination based on a command from the server 10. For example, the control unit 21 autonomously drives the autonomous transport vehicle 20 to the standby position of the trolley 30 based on a command from the server 10. Further, for example, the control unit 21 autonomously drives the autonomous transport vehicle 20 to the warehouse in which the article to be transported is stored while the carriage 30 is towed based on the command from the server 10. Further, for example, the control unit 21 autonomously drives the autonomous transport vehicle 20 to the transport position of the article in a state where the carriage 30 containing the article to be transported is towed based on the command from the server 10.

The image pickup unit 22 is configured to acquire the state of the trolley 30. Specifically, the image pickup unit 22 is configured to acquire the state of the feature point 31 of the carriage 30. The imaging unit 22 is configured to acquire the state of the feature point 31 of the trolley 30 as an image pickup result by imaging the feature point 31 of the trolley 30. The image pickup unit 22 includes a camera. The image pickup unit 22 is provided at a position where the feature point 31 of the carriage 30 can be imaged. The image pickup unit 22 is provided on a portion of the transport vehicle main body 27 on the carriage 30 side.

The communication unit 23 is configured to be able to send and receive information to and from the server 10. The communication unit 23 is a wireless communication unit for wireless communication. The autonomous carrier 20 is communicably connected to the server 10 via a network. The battery 24 is configured to supply electric power to each part of the autonomous carrier 20. The battery 24 includes a rechargeable battery. The autonomous transport vehicle 20 autonomously travels by the electric power of the battery 24. The tilt sensor 25 is configured to acquire the tilt angle in the vertical plane of the autonomous transport vehicle 20 and transmit it to the control unit 21. The tilt sensor 25 includes, for example, a gyro sensor. The storage unit 26 includes a rewritable storage medium such as a flash memory, and is configured to be able to store various types of information. The storage unit 26 stores information on the autonomous transport vehicle 20, information on the trolley 30, and the like.

(Structure of dolly)
Next, the configuration of the carriage 30 will be described.

The dolly 30 is configured to accommodate articles used in the manufacturing plant. As shown in FIG. 4, the dolly 30 includes a feature point 31, an accommodating portion 32, and a plurality (four) wheels 33.

The feature point 31 includes a marker provided on the dolly 30. The marker is not particularly limited, but can be formed by, for example, sheet metal. Further, the feature point 31 is provided at a position where the image pickup unit 22 of the autonomous transport vehicle 20 can take an image. The feature point 31 is provided on the portion of the carriage 30 on the autonomous carrier 20 side. As shown in FIG. 5, a pattern is attached to the feature point 31. The pattern of the feature point 31 can be formed by a laser when the feature point 31 is made of sheet metal. The pattern of the feature point 31 is configured so that the shape seen from the autonomous transport vehicle 20 changes according to the change in the relative posture of the carriage 30 with respect to the transport vehicle main body 27. Further, the pattern of the feature point 31 is composed of a two-dimensional code including the identification information of the dolly 30. The control unit 21 of the autonomous transport vehicle 20 can acquire the identification information of the trolley 30 based on the image pickup result of the feature point 31 by the image pickup unit 22. Further, the control unit 21 of the autonomous transport vehicle 20 obtains information on the trolley 30 such as the shape of the trolley 30, the weight of the trolley 30, and the position of the center of gravity of the trolley 30 from the server 10 based on the identification information of the trolley 30. It can be obtained.

As shown in FIG. 4, the accommodating portion 32 is configured to be capable of accommodating articles. The accommodating portion 32 is formed in a concave shape. The plurality of wheels 33 are configured to drive the carriage 30 by towing by the autonomous transport vehicle 20. The plurality of wheels 33 are provided as universal wheels. Two wheels 33 are provided on each of the left and right sides of the carriage 30.

(Control of running speed of the carrier body)
Next, the control of the traveling speed of the transport vehicle main body 27 will be described.

Here, in the present embodiment, as shown in FIG. 6, the control unit 21 detects the relative posture of the trolley 30 with respect to the transport vehicle main body 27 based on the state of the trolley 30 acquired by the image pickup unit 22, and also detects the relative posture of the trolley 30 with respect to the transport vehicle main body 27. It is configured to control the traveling speed of the transport vehicle main body 27 based on the relative posture of the carriage 30 with respect to the transport vehicle main body 27. Specifically, the control unit 21 is configured to detect the relative posture of the trolley 30 with respect to the transport vehicle main body 27 based on the state of the feature point 31 of the trolley 30 acquired by the imaging unit 22.

In a state where the carriage 30 is towed straight by the transport vehicle main body 27, the feature point 31 is located in the center of the image pickup result, and the feature point 31 is reflected without being tilted. Further, when the carriage 30 is tilted in the horizontal plane and is towed by the transport vehicle main body 27, the feature point 31 is located at a position deviated from the center in the imaging result, and the feature point 31 is tilted in the depth direction. It is reflected. Further, in a state where the bogie 30 is tilted in the vertical plane and is towed by the transport vehicle main body 27, the feature point 31 is located at the center in the imaging result and the feature point 31 is in a plane orthogonal to the depth direction. It looks tilted. The relative posture of the carriage 30 with respect to the transport vehicle main body 27 can be detected by utilizing the change in the state of the feature points 31. Note that FIG. 6 exaggerates the state in which the bogie 30 is tilted in the vertical plane for ease of understanding.

The relative posture of the trolley 30 with respect to the transport vehicle main body 27 includes information on the inclination angle of the trolley 30 with respect to the transport vehicle main body 27. Specifically, the relative posture of the trolley 30 with respect to the transport vehicle main body 27 is information on the inclination angle γ of the trolley 30 with respect to the transport vehicle main body 27 in the horizontal plane and the inclination angle θ of the trolley 30 with respect to the transport vehicle main body 27 in the vertical plane. Contains information about.

The control unit 21 is configured to control the traveling speed of the transport vehicle main body 27 based on the information of the inclination angle of the carriage 30 with respect to the transport vehicle main body 27. Specifically, the control unit 21 controls the traveling speed of the transport vehicle body 27 so that the transport vehicle body 27 decelerates based on the information of the inclination angle γ of the carriage 30 with respect to the transport vehicle body 27 in the horizontal plane. It is configured as follows. More specifically, the control unit 21 is configured to control the traveling speed of the transport vehicle main body 27 by the following equation (1). The control unit 21 is configured to control the traveling speed of the transport vehicle main body 27 so that the traveling speed decreases as the inclination angle γ increases according to the following equation (1).
Vc = V × {1-k × sin (γ)} ・・・ (1)
here,
Vc: Correction speed V: Normal speed k: Correction coefficient γ: The inclination angle of the carriage with respect to the transport vehicle main body in the horizontal plane.

The normal speed V and the correction coefficient k can be determined in advance by an experiment or the like. The normal speed V is not particularly limited, but may be, for example, about 2 m / s. The correction coefficient k is not particularly limited, but may be, for example, a value such that the correction speed Vc is 1 m / s or less. Further, the normal speed V is the traveling speed of the transport vehicle main body 27 in a state where the carriage 30 is towed straight by the transport vehicle main body 27.

Further, the control unit 21 controls the traveling speed of the transport vehicle body 27 so that the transport vehicle body 27 stops based on the information of the inclination angle θ of the carriage 30 with respect to the transport vehicle body 27 in the vertical plane. It is configured. Specifically, the control unit 21 includes information on the tilt angle θ of the carriage 30 with respect to the transport vehicle body 27 in the vertical plane and information on the tilt angle δ of the transport vehicle main body 27 in the vertical plane acquired by the tilt sensor 25. Based on the above, the traveling speed of the transport vehicle main body 27 is controlled so that the transport vehicle main body 27 stops.

First, the control unit 21 acquires the difference (θ−δ) between the tilt angle θ and the tilt angle δ as the true tilt angle θt of the carriage 30 in the vertical plane. Then, the control unit 21 detects whether or not the true inclination angle θt exceeds the reference angle (threshold value). When the control unit 21 detects that the true inclination angle θt exceeds the reference angle, the control unit 21 controls the traveling speed of the transport vehicle main body 27 so that the transport vehicle main body 27 stops. At this time, the control unit 21 controls the traveling speed of the transport vehicle main body 27 so that the transport vehicle main body 27 gradually decelerates and stops. Further, when the control unit 21 detects that the true inclination angle θt does not exceed the reference angle, the control unit 21 controls to continue the traveling of the transport vehicle main body 27. The reference angle can be determined in advance by an experiment or the like.

Further, in the present embodiment, the control unit 21 controls the traveling speed of the transport vehicle main body 27 in consideration of at least one of the shape of the carriage 30, the weight of the carriage 30, and the position of the center of gravity of the carriage 30. It is configured as follows. For example, in consideration of the shape of the carriage 30, the control unit 21 reduces the traveling speed of the transport vehicle main body 27 when the width of the carriage 30 is large as compared with the case of the carriage 30 having a small width. Similarly, in consideration of the shape of the carriage 30, the control unit 21 increases the traveling speed of the transport vehicle main body 27 when the width of the carriage 30 is small as compared with the case of the carriage 30 having a large width.

Further, for example, the control unit 21 considers the weight of the trolley 30 and reduces the traveling speed of the transport vehicle main body 27 when the trolley 30 is heavy as compared with the case where the trolley 30 is light in weight. Similarly, in consideration of the weight of the trolley 30, the control unit 21 increases the traveling speed of the transport vehicle main body 27 when the weight of the trolley 30 is small as compared with the case of the trolley 30 having a large weight.

Further, for example, the control unit 21 considers the position of the center of gravity of the bogie 30 and, when the position of the center of gravity of the bogie 30 is on the left side, the transport vehicle main body when turning counterclockwise as compared with the case where the bogie 30 turns clockwise. Decrease the traveling speed of 27. Similarly, in consideration of the position of the center of gravity of the trolley 30, the control unit 21 considers the position of the center of gravity of the trolley 30 on the right side, and the transport vehicle main body 27 when the trolley 30 turns clockwise as compared with the case where the trolley 30 turns counterclockwise. Reduce the running speed of.

(Drive control of connecting part)
Next, the drive control of the connecting portion 20d will be described.

As shown in FIG. 7, the control unit 21 drives (rotates) the connecting portion 20d by the connecting portion motor 20e when the carriage 30 is towed by the transport vehicle main body 27, whereby the carriage 30 with respect to the transport vehicle main body 27 in the horizontal plane is driven (rotated). It is configured to control the relative posture of. Specifically, the control unit 21 drives (rotates) the connecting portion 20d by the connecting portion motor 20e when the transport vehicle main body 27 turns, so that the movement of the carriage 30 due to inertia is canceled, and the transport is carried out in the horizontal plane. It is configured to control the relative posture of the bogie 30 with respect to the car body 27.

Here, the inertial force acting on the carriage 30 when the transport vehicle main body 27 turns can be expressed by the following equation (2).
Fj = m × a ・・・ (2)
here,
Fj: Inertial force acting on the trolley m: Weight of the trolley a: Acceleration in the rotation direction of the trolley.

As the weight m, the total weight of the weight of the trolley 30 and the weight of the article is used when the article is being transported, and the weight of the trolley 30 is used when the article is not being transported. The weight of the dolly 30 can be acquired from the server 10 based on the identification information of the dolly 30. Further, the weight of the article can be obtained by specifying the article based on the content of the command (content of the task) from the server 10. The acceleration a can be obtained from the turning speed of the transport vehicle main body 27 by using a conversion table. Alternatively, the acceleration a can be acquired from the time change of the state of the feature point 31 of the carriage 30 acquired by the imaging unit 22.

Further, the dynamic frictional force acting on the carriage 30 can be expressed by the following equation (3).
F = μ × m × g ・・・ (3)
here,
F: Dynamic friction force acting on the trolley μ: Dynamic friction coefficient m: Weight of the trolley g: Gravity acceleration.

The dynamic friction coefficient μ can be obtained by the user inputting the dynamic friction coefficient of the floor surface. The weight m can be obtained as in the case of the above formula (2). The gravitational acceleration g can be obtained as a known value.

When the transport vehicle body 27 turns, the carriage 30 is swung in the rotational direction by a force determined by the inertial force Fj obtained by the above formula (2) and the dynamic friction force F obtained by the above formula (3). Therefore, the control unit 21 sets the driving direction of the connecting unit 20d (the direction opposite to the direction in which the inertia works) so as to cancel the difference (Fg-F) between the inertial force Fg and the dynamic friction force F. Determine the drive distance (drive angle). Then, the control unit 21 controls the connection unit 20d to be driven by the connection unit motor 20e so as to rotate by the determined drive distance (drive angle) in the determined drive direction.

Further, in the present embodiment, the control unit 21 drives (rotates) the connecting portion 20d by the connecting portion motor 20e within the angle range limited by the stopper 20f, so that the trolley 30 with respect to the transport vehicle main body 27 in the horizontal plane is 30. It is configured to control the relative posture of. The control unit 21 is configured to drive (rotate) the connection unit 20d by the connection unit motor 20e within a range in which the connection unit 20d does not come into contact with the stopper 20f.

(Correction time when controlling the running speed)
Next, the correction time at the time of traveling speed control of the transport vehicle main body 27 will be described.

As shown in FIG. 8, the control unit 21 is configured to acquire the correction time T required for correcting the relative posture of the carriage 30 with respect to the transport vehicle main body 27 by controlling the traveling speed of the transport vehicle main body 27. .. Further, the control unit 21 is configured to detect an abnormality in traveling based on a comparison between the correction time T and the reference correction time. Specifically, the control unit 21 is configured to detect an abnormality in traveling by the following equation (4). The control unit 21 is configured to detect a running abnormality when the correction time T deviates from (below or exceeds) the normal range defined by the following equation (4).
Te-α <T <Te + α ... (4)
here,
Te: Reference correction time T: Correction time α: Constant.

The reference correction time Te and the correction time T will be described later. The constant α can be determined in advance by an experiment or the like.

Further, as shown in FIG. 9, a plurality of (four in FIG. 9) areas A are set for correcting the relative posture of the carriage 30 with respect to the transport vehicle main body 27. The plurality of areas A are set as ranges of inclination angles γ different from each other. For example, area 1 has a tilt angle γ of 0 degrees or more and less than 5 degrees, area 2 has a tilt angle γ of 5 degrees or more and less than 10 degrees, and area 3 has a tilt angle γ of 10 degrees or more and less than 15 degrees. Area 4 is set as a range in which the inclination angle γ is 15 degrees or more and less than 20 degrees.

The control unit 21 is configured to control to change the traveling speed of the transport vehicle main body 27 when the area A shifts from the immediately preceding area A to a different area A. Further, the control unit 21 is configured to acquire the time until the area A shifts from the immediately preceding area A to a different area A as the correction time T and store it in the storage unit 26.

Further, in the present embodiment, the control unit 21 is configured to learn the reference correction time Te based on the correction time T. Specifically, the control unit 21 is configured to learn and update the reference correction time Te by the following equation (5). The control unit 21 is configured to learn and update the reference correction time Te as an average value of a plurality of correction times T by the following equation (5). The control unit 21 is configured to acquire the reference correction time Te as the expected correction completion time expected to be completed by the following equation (5).
Te = ΣTn / n ... (5)
here,
Te: Reference correction time Tn: Nth acquired correction time n: Correction time number
Is.

Further, in the present embodiment, the control unit 21 determines the relative posture (area A) of the carriage 30 with respect to the transport vehicle body 27, the traveling speed of the transport vehicle body 27, the weight of the carriage 30, or the traveling direction of the transport vehicle body 27. It is configured to learn the reference correction time Te. Therefore, when the area A shifts from the immediately preceding area A to a different area A, the control unit 21 determines the area A (tilt angle γ), the traveling speed of the transport vehicle main body 27, the weight of the carriage 30, and the transport vehicle main body. It is configured to store the traveling direction of 27 (whether it is a right turn or a left turn) in the storage unit 26 in association with the correction time T. As a result, the correction time T, which is classified according to the area A, the traveling speed of the transport vehicle main body 27, the weight of the carriage 30, or the traveling direction of the transport vehicle main body 27, is acquired. Further, the reference correction time Te, which is classified according to the area A, the traveling speed of the transport vehicle main body 27, the weight of the carriage 30, or the traveling direction of the transport vehicle main body 27, is learned.

Further, the control unit 21 is configured to learn the correction coefficient k of the above equation (1) based on the correction time T. Specifically, the control unit 21 is configured to acquire the correction coefficient k as a random number in a predetermined range. Further, the control unit 21 is configured to learn and update a range of random numbers of the correction coefficient k centering on the value of the correction coefficient k that results in a smaller correction time T. This makes it possible to converge the range of random numbers with the correction coefficient k to an appropriate range.

(Automatic connection control of autonomous transport vehicle)
Next, the automatic connection control of the autonomous transport vehicle 20 will be described.

As shown in FIG. 10, the control unit 21 connects the transport vehicle main body 27 to the bogie 30 when the transport vehicle main body 27 and the bogie 30 are connected, based on the state of the bogie 30 acquired by the image pickup unit 22. It is configured to move to. Specifically, the control unit 21 attaches the transport vehicle main body 27 to the bogie 30 when the transport vehicle main body 27 and the bogie 30 are connected, based on the state of the feature point 31 of the bogie 30 acquired by the image pickup unit 22. It is configured to move to the connecting position.

The control unit 21 is configured to recognize the state of the feature point 31 of the carriage 30 by taking an image with the image pickup unit 22. Then, the control unit 21 is configured to bring the transport vehicle main body 27 closer to the unconnected carriage 30 by using the state of the feature point 31 of the carriage 30 as a mark. Then, when the transport vehicle main body 27 is moved to the connection position with the carriage 30, the control unit 21 is configured to control the connection between the transport vehicle main body 27 and the carriage 30 by the connecting portion 20d. The control unit 21 is configured to tow the carriage 30 connected by the connecting unit 20d and autonomously travel.

(Automatic connection processing of autonomous transport vehicles)
Next, the automatic connection processing of the autonomous transport vehicle 20 of the present embodiment will be described with reference to the flowchart. Each process of the flowchart is performed by the control unit 21.

As shown in FIG. 11, first, in step S101, it is detected whether or not the towing command of the carriage 30 is received from the server 10. The towing command of the trolley 30 includes information on the articles to be loaded on the trolley 30. When it is detected that the towing command of the carriage 30 has not been received, the process of step S101 is repeated. If it is detected that the towing command of the carriage 30 has been received, the process proceeds to step S102.

Then, in step S102, the transport vehicle main body 27 is moved to the designated position designated by the server 10.

Then, in step S103, the feature point 31 of the dolly 30 is recognized by making the image taken by the image pickup unit 22.

Then, in step S104, information on the bogie 30 (shape of the bogie 30, weight of the bogie 30, position of the center of gravity of the bogie 30, etc.) is acquired based on the feature point 31 of the bogie 30. Specifically, in step S104, the identification information of the dolly 30 is acquired from the feature point 31 of the dolly 30. Then, the information of the dolly 30 is acquired from the server 10 based on the identification information of the dolly 30.

Then, in step S105, the transport vehicle main body 27 is approached to the carriage 30 with the feature point 31 of the carriage 30 as a mark.

Then, in step S106, it is detected whether or not the transport vehicle main body 27 has moved to the connection position with the carriage 30. When it is detected that the transport vehicle main body 27 has not moved to the connection position with the carriage 30, the process of step S106 is repeated. Further, when it is detected that the transport vehicle main body 27 has moved to the connection position with the carriage 30, the process proceeds to step S107.

Then, in step S107, the transport vehicle main body 27 and the carriage 30 are connected by the connecting portion 20d. Then, in step S107, the towing running of the carriage 30 by the transport vehicle main body 27 is started. After that, the automatic connection process is terminated.

(Speed control processing of autonomous transport vehicle)
Next, the speed control process of the autonomous transport vehicle 20 of the present embodiment will be described with reference to the flowchart. Each process of the flowchart is performed by the control unit 21.

As shown in FIG. 12, first, in step S111, the state of the feature point 31 of the dolly 30 is acquired by taking an image by the image pickup unit 22.

Then, in step S112, the relative posture of the carriage 30 with respect to the transport vehicle main body 27 in the horizontal plane is detected based on the state of the feature point 31 of the carriage 30. In step S112, the inclination angle γ of the carriage 30 with respect to the transport vehicle main body 27 in the horizontal plane is detected based on the state of the feature point 31 of the carriage 30.

Then, in step S113, it is detected whether or not the area A is the first area A (the area A in which the dolly 30 is towed straight). If it is detected that the area A is the first area A, the process proceeds to step S114.

Then, in step S114, the traveling speed of the transport vehicle main body 27 is set to the normal speed.

Then, in step S115, it is detected whether or not the transportation is completed. When it is detected that the transport is completed, the speed control process is terminated. If it is detected that the transfer is not completed, the process returns to step S111.

If it is detected in step S113 that the area A is not the first area A, the process proceeds to step S116.

Then, in step S116, it is detected whether or not the area A is an area A different from the immediately preceding area A. When it is detected that the area A is not an area A different from the immediately preceding area A, the process proceeds to step S115, and the same processing as described above is performed. If it is detected that the area A is different from the immediately preceding area A, the process proceeds to step S117.

Then, as shown in FIG. 13, in step S117, the traveling speed of the transport vehicle main body 27 is corrected according to the inclination angle γ of the carriage 30 with respect to the transport vehicle main body 27 in the horizontal plane. In step S117, the traveling speed of the transport vehicle main body 27 is corrected by the above equation (1).

Then, in step S118, the correction time T is stored in the storage unit 26. Further, in step S118, the area A (inclination angle γ), the traveling speed of the transport vehicle main body 27, the weight of the carriage 30, and the traveling direction of the transport vehicle main body 27 are stored in the storage unit 26 in association with the correction time T. Will be done.

Then, in step S119, the correction time T and the reference correction time Te are compared.

Then, in step S120, it is detected by the above equation (4) whether or not the correction time T is within the normal range. If it is detected that the correction time T is within the normal range, the process proceeds to step S121.

Then, in step S121, the reference correction time Te is learned and updated by the above equation (5) based on the correction time T. Then, the process proceeds to step S115, and the same processing as described above is performed.

If it is detected in step S120 that the correction time T is not in the normal range, the process proceeds to step S122.

Then, in step S122, an abnormality notification is performed. In step S122, for example, an abnormality notification is sent to the server 10. Then, the abnormality is displayed on the display unit 13 of the server 10. After that, the speed control process is terminated.

(Traveling stop processing of autonomous transport vehicle)
Next, the traveling stop processing of the autonomous transport vehicle 20 of the present embodiment will be described with reference to the flowchart. Each process of the flowchart is performed by the control unit 21.

As shown in FIG. 14, first, in step S131, the state of the feature point 31 of the dolly 30 is acquired by taking an image by the image pickup unit 22.

Then, in step S132, the relative posture of the carriage 30 with respect to the transport vehicle main body 27 in the vertical plane is detected based on the state of the feature point 31 of the carriage 30. In step S132, the inclination angle θ of the carriage 30 with respect to the transport vehicle main body 27 in the vertical plane is detected based on the state of the feature point 31 of the carriage 30.

Then, in step S133, the tilt sensor 25 detects the tilt angle δ of the transport vehicle main body 27 in the vertical plane.

Then, in step S134, it is detected whether or not the true inclination angle θt (= θ−δ) of the carriage 30 is abnormal. If it is detected that the true inclination angle θt of the carriage 30 is not abnormal, the process proceeds to step S135.

Then, in step S135, it is detected whether or not the transportation is completed. When it is detected that the transportation is completed, the traveling stop processing is terminated. If it is detected that the transfer is not completed, the process returns to step S131.

Further, if it is detected in step S134 that the true inclination angle θt of the carriage 30 is abnormal, the process proceeds to step S136.

Then, in step S136, the traveling of the transport vehicle main body 27 is stopped. In step S135, the transport vehicle main body 27 is gradually decelerated and the traveling of the transport vehicle main body 27 is stopped.

Then, in step S137, an abnormality notification is performed. In step S137, for example, an abnormality notification is sent to the server 10. Then, the abnormality is displayed on the display unit 13 of the server 10. After that, the running stop process is completed.

(Control processing of the connection part of the autonomous carrier)
Next, the connection portion control process of the autonomous transport vehicle 20 of the present embodiment will be described with reference to the flowchart. Each process of the flowchart is performed by the control unit 21.

As shown in FIG. 15, first, in step S141, the state of the feature point 31 of the dolly 30 is acquired by taking an image by the image pickup unit 22.

Then, in step S142, the relative posture of the carriage 30 with respect to the transport vehicle main body 27 in the horizontal plane is detected based on the state of the feature point 31 of the carriage 30. In step S142, the inclination angle γ of the carriage 30 with respect to the transport vehicle main body 27 in the horizontal plane is detected based on the state of the feature point 31 of the carriage 30.

Then, in step S143, it is detected whether or not the area A is the first area A (the area A in which the dolly 30 is towed straight). If it is detected that the area A is the first area A, the process proceeds to step S144.

Then, in step S144, it is detected whether or not the transportation is completed. When it is detected that the transport is completed, the connection unit control process is terminated. If it is detected that the transport is not completed, the process returns to step S141.

If it is detected in step S143 that the area A is not the first area A, the process proceeds to step S145.

Then, in step S145, the inertial force Fj acting on the carriage 30 is acquired by the above equation (2), and the dynamic friction force F acting on the carriage 30 is acquired by the above equation (3).

Then, in step S146, the connecting portion 20d is driven (rotated) by the connecting portion motor 20e so as to cancel the movement of the carriage 30 due to the inertia based on the inertial force Fj and the dynamic friction force F. Then, the process proceeds to step S144, and the same processing as described above is performed.

(Effect of this embodiment)
In this embodiment, the following effects can be obtained.

In the present embodiment, as described above, the traveling control method of the autonomous transport vehicle 20 includes a step of detecting the relative posture of the carriage 30 with respect to the transport vehicle main body 27 based on the state of the carriage 30, and a step with respect to the transport vehicle main body 27. A step for controlling the traveling speed of the transport vehicle main body 27 based on the relative posture of the carriage 30 is provided. As a result, when a change in the relative posture of the trolley 30 with respect to the transport vehicle main body 27 occurs when moving a bent portion such as a corner, the transport vehicle main body 27 responds to the change in the relative posture of the trolley 30 with respect to the transport vehicle main body 27. The traveling speed can be changed appropriately. As a result, unlike the case where the traveling speed of the transport vehicle main body 27 is uniformly reduced when the carriage 30 is towed by the transport vehicle main body 27, an unnecessary decrease in the traveling speed does not occur. As a result, when the carriage 30 is towed by the transport vehicle main body 27, the productivity can be improved while suppressing the carriage 30 from tipping over at the bent portion. Further, when an abnormality occurs in the posture of the carriage 30 when the carriage 30 is towed by the carrier body 27, the traveling speed of the carrier body 27 can be appropriately changed. This also makes it possible to prevent the carriage 30 from tipping over when the carriage 30 is towed by the transport vehicle main body 27.

Further, in the present embodiment, as described above, the step of acquiring the state of the carriage 30 includes the step of acquiring the state of the feature point 31 of the carriage 30. Further, the step of detecting the relative posture of the carriage 30 with respect to the transport vehicle main body 27 includes a step of detecting the relative posture of the carriage 30 with respect to the transport vehicle main body 27 based on the state of the feature point 31 of the carriage 30. As a result, the relative posture of the carriage 30 with respect to the transport vehicle main body 27 can be easily detected by simply acquiring the state of the feature point 31 of the carriage 30. Further, since it is not necessary to provide the trolley 30 with a sensor for detecting the posture, it is possible to detect the relative posture of the trolley 30 while making the trolley 30 a simple structure.

Further, in the present embodiment, as described above, the feature point 31 of the dolly 30 includes the marker provided on the dolly 30. As a result, unlike the case where the shape of the corner portion of the trolley 30 is used as the feature point 31, the relative posture of the trolley 30 with respect to the transport vehicle main body 27 can be detected by using a dedicated marker. As a result, the relative posture of the carriage 30 with respect to the transport vehicle main body 27 can be accurately detected.

Further, in the present embodiment, as described above, the relative posture of the carriage 30 with respect to the transport vehicle main body 27 includes information on the inclination angle of the carriage 30 with respect to the transport vehicle main body 27. Further, the step of controlling the traveling speed of the transport vehicle main body 27 includes a step of controlling the traveling speed of the transport vehicle main body 27 based on the information of the inclination angle of the carriage 30 with respect to the transport vehicle main body 27. Thereby, the traveling speed of the transport vehicle main body 27 can be accurately controlled based on the information of the inclination angle of the carriage 30 with respect to the transport vehicle main body 27.

Further, in the present embodiment, as described above, the step of controlling the traveling speed of the transport vehicle main body 27 is performed by the transport vehicle main body 27 based on the information of the inclination angle γ of the carriage 30 with respect to the transport vehicle main body 27 in the horizontal plane. It includes a step of controlling the traveling speed of the transport vehicle main body 27 so as to decelerate. As a result, when the tilt angle γ of the carriage 30 with respect to the transport vehicle body 27 in the horizontal plane changes when the bending point such as a corner is moved, the change in the tilt angle γ of the carriage 30 with respect to the transport vehicle main body 27 in the horizontal plane. Therefore, the traveling speed of the transport vehicle main body 27 can be appropriately reduced. As a result, the traveling speed of the transport vehicle main body 27 can be accurately controlled when the bent portion is moved.

Further, in the present embodiment, as described above, the step of controlling the traveling speed of the transport vehicle main body 27 is based on the information of the inclination angle θ of the carriage 30 with respect to the transport vehicle main body 27 in the vertical plane. Includes a step of controlling the traveling speed of the transport vehicle body 27 so that As a result, for example, when an abnormality occurs in the posture of the trolley 30 due to an abnormality in the wheels 33 of the trolley 30, and the inclination angle θ of the trolley 30 with respect to the transport vehicle main body 27 in the vertical plane changes. The main body 27 can be stopped. As a result, it is possible to prevent the carriage 30 from tipping over when the carriage 30 is towed by the transport vehicle main body 27.

Further, in the present embodiment, as described above, the traveling control method of the autonomous transport vehicle 20 includes a step of acquiring information on the inclination angle δ of the transport vehicle main body 27 in the vertical plane. Further, the step of controlling the traveling speed of the transport vehicle main body 27 includes information on the inclination angle θ of the carriage 30 with respect to the transport vehicle main body 27 in the vertical plane and information on the inclination angle δ of the transport vehicle main body 27 in the vertical plane. Based on this, a step of controlling the traveling speed of the transport vehicle main body 27 is included so that the transport vehicle main body 27 stops. As a result, control is performed to stop the transport vehicle body 27 based not only on the tilt angle θ of the carriage 30 with respect to the transport vehicle body 27 in the vertical plane but also on the tilt angle δ of the transport vehicle body 27 in the vertical plane. Can be done. As a result, the control for stopping the transport vehicle main body 27 can be accurately performed.

Further, in the present embodiment, as described above, the step of controlling the traveling speed of the transport vehicle main body 27 considers at least one of the shape of the carriage 30, the weight of the carriage 30, and the position of the center of gravity of the carriage 30. Then, a step of controlling the traveling speed of the transport vehicle main body 27 is included. Thereby, the traveling speed of the transport vehicle main body 27 can be controlled in consideration of at least one of the shape of the carriage 30, the weight of the carriage 30, and the position of the center of gravity of the carriage 30, which differ depending on the type of the carriage 30. .. As a result, the traveling speed of the transport vehicle main body 27 can be appropriately controlled according to the type of the carriage 30.

Further, in the present embodiment, as described above, the transport vehicle main body 27 includes a connecting portion 20d that connects the transport vehicle main body 27 and the carriage 30. Further, the transport vehicle main body 27 includes a connecting portion motor 20e that drives the connecting portion 20d. Further, the traveling control method of the autonomous transport vehicle 20 is such that when the carriage 30 is towed by the transport vehicle main body 27, the connecting portion 20d is driven by the connecting portion motor 20e so that the carriage 30 is relative to the transport vehicle main body 27 in the horizontal plane. It has a step to control the posture. As a result, the transport vehicle main body 27 can be driven while controlling the relative posture of the carriage 30 with respect to the transport vehicle main body 27 in the horizontal plane. As a result, the running stability of the transport vehicle main body 27 can be improved as compared with the case where the relative posture of the carriage 30 with respect to the transport vehicle main body 27 in the horizontal plane cannot be controlled.

Further, in the present embodiment, as described above, in the step of controlling the relative posture of the carriage 30 with respect to the transport vehicle main body 27 in the horizontal plane, the connecting portion 20d is driven by the connecting portion motor 20e when the transport vehicle main body 27 is turned. Thereby, the step of controlling the relative posture of the carriage 30 with respect to the transport vehicle main body 27 in the horizontal plane is included so as to cancel the movement of the carriage 30 due to inertia. As a result, it is possible to prevent the carriage 30 from moving so as to be shaken due to inertia when the transport vehicle main body 27 is turned. As a result, the carriage 30 can be moved compactly when the transport vehicle main body 27 turns. As a result, it is possible to easily perform a running operation such as turning and turning in a narrow bent portion.

Further, in the present embodiment, as described above, the transport vehicle main body 27 includes the stopper 20f that restricts the movement of the connecting portion 20d. Further, in the step of controlling the relative posture of the carriage 30 with respect to the transport vehicle main body 27 in the horizontal plane, the connecting portion 20d is driven by the connecting portion motor 20e within the angle range limited by the stopper 20f, thereby transporting in the horizontal plane. It includes a step of controlling the relative posture of the bogie 30 with respect to the car body 27. Thereby, when the connecting portion 20d is driven by the connecting portion motor 20e, the connecting portion 20d can be driven so as not to come into contact with the stopper 20f. As a result, it is possible to suppress that a load is applied to both the connecting portion 20d and the stopper 20f due to the contact between the connecting portion 20d and the stopper 20f when the connecting portion 20d is driven by the connecting portion motor 20e. can. Further, by providing the stopper 20f, the movement of the connecting portion 20d can be restricted. As a result, by limiting the movement of the connecting portion 20d, the movement of the carriage 30 can be restricted to a predetermined range.

Further, in the present embodiment, as described above, the step of controlling the traveling speed of the transport vehicle main body 27 is necessary for correcting the relative posture of the carriage 30 with respect to the transport vehicle main body 27 by controlling the traveling speed of the transport vehicle main body 27. It includes a step of acquiring the corrected correction time T and a step of detecting an abnormality in running based on the comparison between the correction time T and the reference correction time Te. Thereby, it is possible to detect an abnormality in running caused by an abnormality such as an abnormality on the floor surface and an abnormality on the wheels of the bogie 30. As a result, when a running abnormality is detected, the running abnormality can be quickly resolved.

Further, in the present embodiment, as described above, the step of controlling the traveling speed of the transport vehicle main body 27 includes a step of learning the reference correction time Te based on the correction time T. Thereby, the reference correction time Te can be updated by learning. As a result, the updated reference correction time Te makes it possible to detect running abnormalities more accurately.

Further, in the present embodiment, as described above, the step of learning the reference correction time Te is the relative posture of the carriage 30 with respect to the transport vehicle main body 27, the traveling speed of the transport vehicle main body 27, the weight of the carriage 30, or the transport vehicle. A step of learning the reference correction time Te is included for each traveling direction of the main body 27. Thereby, the reference correction time Te can be learned for each case. As a result, it is possible to detect the abnormality of running more accurately according to each case by the reference correction time Te divided into cases.

Further, in the present embodiment, as described above, the traveling control method of the autonomous transport vehicle 20 is based on the state of the carriage 30, and when the transport vehicle main body 27 and the carriage 30 are connected, the transport vehicle main body 27 is connected to the carriage 30. It is provided with a step of moving to a connection position with. As a result, the transport vehicle main body 27 and the carriage 30 can be automatically connected. As a result, it is possible to automate from the connection between the transport vehicle main body 27 and the carriage 30 to the towing running of the carriage 30 by the transport vehicle main body 27.

(Modification example)
It should be noted that the embodiments disclosed this time are exemplary in all respects and are not considered to be restrictive. The scope of the present invention is shown by the scope of claims rather than the description of the above-described embodiment, and further includes all modifications (modifications) within the meaning and scope equivalent to the scope of claims.

For example, in the above embodiment, an example in which the autonomous transport vehicle is provided with four drive wheels is shown, but the present invention is not limited to this. In the present invention, the autonomous carrier vehicle may include a plurality of drive wheels other than four. Further, the autonomous carrier vehicle may be provided with universal wheels in addition to the drive wheels.

Further, in the above embodiment, an example is shown in which the autonomous transport vehicle includes an image pickup unit as a state acquisition unit of the present invention, but the present invention is not limited to this. In the present invention, the autonomous carrier may include a state acquisition unit other than an image pickup unit such as a three-dimensional shape measurement unit using a laser. In this case, the pattern of the feature points may be formed by a three-dimensional shape such as unevenness.

Further, in the above embodiment, an example is shown in which an imaging unit (state acquisition unit) and a feature point are provided one by one, but the present invention is not limited to this. In the present invention, a plurality of state acquisition units and a plurality of feature points may be provided. In the modified example shown in FIG. 16, the autonomous transport vehicle 20 is provided with a plurality (two) image pickup units 22. Further, the carriage 30 is provided with a plurality (two) feature points 31. In this case, since the states of the plurality of feature points 31 can be acquired, the relative posture of the carriage 30 with respect to the transport vehicle main body 27 can be detected more accurately based on the states of the plurality of feature points 31.

Further, in the above embodiment, an example is shown in which the feature points include a marker provided on the carriage, but the present invention is not limited to this. In the present invention, the feature point may include a characteristic shape portion such as a corner portion of the carriage.

Further, in the above embodiment, the traveling speed of the transport vehicle body is controlled with respect to the tilt angle of the carriage with respect to the transport vehicle body in the horizontal plane, and the traveling speed of the transport vehicle body is controlled with respect to the tilt angle of the carriage with respect to the transport vehicle body in the vertical plane. However, the present invention is not limited to this. In the present invention, of the control of the traveling speed of the transport vehicle body with respect to the tilt angle of the carriage with respect to the transport vehicle body in the horizontal plane and the control of the traveling speed of the transport vehicle body with respect to the tilt angle of the carriage with respect to the transport vehicle body in the vertical plane. Only one of the above may be performed.

Further, in the above embodiment, an example of stopping the transport vehicle main body based on the information of the tilt angle of the carriage with respect to the transport vehicle main body in the vertical plane and the information of the tilt angle of the transport vehicle main body in the vertical plane is shown. However, the present invention is not limited to this. In the present invention, the transport vehicle main body may be stopped based only on the information of the inclination angle of the carriage with respect to the transport vehicle main body in the vertical plane.

Further, in the above embodiment, an example of controlling the traveling speed of the transport vehicle main body in consideration of at least one of the shape of the carriage, the weight of the carriage, and the position of the center of gravity of the carriage has been shown. Not limited to this. In the present invention, it is not necessary to consider the shape of the carriage, the weight of the carriage, and the position of the center of gravity of the carriage in controlling the traveling speed of the carrier body.

Further, in the above embodiment, an example in which the autonomous transport vehicle is provided with a connecting portion is shown, but the present invention is not limited to this. In the present invention, the dolly may include a connecting portion.

Further, in the above embodiment, an example in which the autonomous transport vehicle is provided with a connecting portion motor is shown, but the present invention is not limited to this. In the present invention, the autonomous carrier vehicle does not have to be provided with a connecting motor.

Further, in the above embodiment, an example in which the autonomous transport vehicle is provided with a pair (two) of stoppers is shown, but the present invention is not limited to this. In the present invention, the autonomous carrier may be provided with a plurality of stoppers other than one or two. Further, the autonomous carrier vehicle does not have to be provided with a stopper.

Further, in the above embodiment, an example of acquiring a correction time and detecting a running abnormality based on the correction time has been shown, but the present invention is not limited to this. In the present invention, it is not necessary to acquire the correction time.

Further, in the above embodiment, an example of learning the reference correction time based on the correction time is shown, but the present invention is not limited to this. In the present invention, the reference correction time may be a fixed value.

Further, in the above embodiment, an example is shown in which the transport vehicle main body is moved to the connection position with the carriage when the transport vehicle main body and the carriage are connected based on the state of the carriage, but the present invention is not limited to this. .. In the present invention, it is not necessary to move the transport vehicle main body to the connection position with the carriage when the transport vehicle main body and the carriage are connected based on the state of the carriage.

Further, in the above embodiment, for convenience of explanation, the control processing has been described using a flow-driven flow in which the control processing is sequentially performed along the processing flow, but the present invention is not limited to this. In the present invention, the control process may be performed by an event-driven type (event-driven type) process in which the process is executed in event units. In this case, it may be completely event-driven, or it may be a combination of event-driven and flow-driven.

10 Server (control device)
20 Autonomous transport vehicle 20d Connecting part 20e Connecting part Motor (driving part)
20f Stopper 21 Control unit (conveyor vehicle control unit)
22 Imaging unit (state acquisition unit)
27 Transport vehicle body 30 Truck 31 Feature points 100 Transport system T Correction time Te Reference correction time γ Tilt angle of the truck with respect to the transport vehicle body in the horizontal plane δ Tilt angle of the transport vehicle body in the vertical plane θ Tilt angle of the transport vehicle body in the vertical plane θ Tilt angle of the trolley with respect to

Claims

It is a running control method for autonomous transport vehicles that tow a dolly and run autonomously.
The step of acquiring the state of the dolly and
A step of detecting the relative posture of the dolly with respect to the main body of the dolly based on the state of the dolly.
A traveling control method for an autonomous transport vehicle, comprising: a step of controlling a traveling speed of the transport vehicle main body based on a relative posture of the carriage with respect to the transport vehicle main body.
The step of acquiring the state of the dolly includes a step of acquiring the state of the feature point of the dolly.
The first aspect of the present invention, wherein the step of detecting the relative posture of the carriage with respect to the transport vehicle main body includes a step of detecting the relative posture of the carriage with respect to the transport vehicle main body based on the state of the feature points of the carriage. Travel control method for autonomous vehicles.
The feature of the trolley is the traveling control method of the autonomous transport vehicle according to claim 2, which includes a marker provided on the trolley.
The relative posture of the dolly with respect to the carrier body includes information on the inclination angle of the dolly with respect to the carrier body.
Any of claims 1 to 3, wherein the step of controlling the traveling speed of the transport vehicle main body includes a step of controlling the traveling speed of the transport vehicle main body based on the information of the inclination angle of the carriage with respect to the transport vehicle main body. The traveling control method for an autonomous carrier according to item 1.
The step of controlling the traveling speed of the transport vehicle body is to reduce the traveling speed of the transport vehicle body so that the transport vehicle body decelerates based on the information of the inclination angle of the carriage with respect to the transport vehicle body in the horizontal plane. The traveling control method for an autonomous carrier according to claim 4, which comprises a step of controlling.
The step of controlling the traveling speed of the transport vehicle body is the traveling speed of the transport vehicle body so that the transport vehicle body stops based on the information of the inclination angle of the carriage with respect to the transport vehicle body in the vertical plane. The traveling control method for an autonomous carrier according to claim 4 or 5, which comprises a step of controlling.
Further provided with a step of acquiring information on the tilt angle of the carrier body in a vertical plane.
The step of controlling the traveling speed of the transport vehicle body is based on the information of the inclination angle of the carriage with respect to the transport vehicle body in the vertical plane and the information of the inclination angle of the transport vehicle main body in the vertical plane. The traveling control method for an autonomous transport vehicle according to claim 6, further comprising a step of controlling the traveling speed of the transport vehicle main body so that the transport vehicle main body stops.
The step of controlling the traveling speed of the transport vehicle main body controls the traveling speed of the transport vehicle main body in consideration of at least one of the shape of the carriage, the weight of the carriage, and the position of the center of gravity of the carriage. The traveling control method for an autonomous carrier according to any one of claims 1 to 7, which comprises the step of performing.
The transport vehicle body or the carriage includes a connecting portion that connects the transport vehicle body and the carriage.
The transport vehicle main body includes a drive unit that drives the connection unit, and includes a drive unit.
Claims 1 to 8 further include a step of controlling the relative posture of the trolley with respect to the transport vehicle main body in a horizontal plane by driving the connecting portion by the driving portion when the trolley is towed by the transport vehicle main body. The traveling control method for an autonomous carrier according to any one of the above items.
The step of controlling the relative posture of the bogie with respect to the transport vehicle body in the horizontal plane is such that the movement of the bogie due to inertia is canceled by driving the connecting portion by the drive unit when the transport vehicle main body turns. The traveling control method for an autonomous transport vehicle according to claim 9, further comprising a step of controlling the relative posture of the carriage with respect to the transport vehicle main body in a horizontal plane.
The transport vehicle body further includes a stopper that limits the movement of the connecting portion.
The step of controlling the relative posture of the bogie with respect to the transport vehicle body in the horizontal plane is to drive the connecting portion by the drive unit within the angle range limited by the stopper, thereby driving the transport vehicle main body in the horizontal plane. The traveling control method for an autonomous carrier according to claim 9 or 10, comprising a step of controlling the relative posture of the carriage with respect to the vehicle.
The step of controlling the traveling speed of the carrier body is
A step of acquiring the correction time required for correcting the relative posture of the bogie with respect to the transport vehicle body by controlling the traveling speed of the transport vehicle body, and
The traveling control method for an autonomous carrier according to any one of claims 1 to 11, further comprising a step of detecting an abnormality in traveling based on a comparison between the correction time and a reference correction time.
The traveling control method for an autonomous transport vehicle according to claim 12, wherein the step of controlling the traveling speed of the transport vehicle main body further includes a step of learning the reference correction time based on the correction time.
The step of learning the reference correction time is the reference correction time for each of the relative posture of the carriage with respect to the transport vehicle body, the traveling speed of the transport vehicle body, the weight of the carriage, or the traveling direction of the transport vehicle body. 13. The traveling control method for an autonomous carrier according to claim 13, which comprises a step of learning.
The invention according to any one of claims 1 to 14, further comprising a step of moving the transport vehicle main body to a connection position with the carriage when the transport vehicle main body and the carriage are connected based on the state of the carriage. The described method for controlling the traveling of an autonomous transport vehicle.
It is an autonomous transport vehicle that tows a dolly and runs autonomously.
A state acquisition unit that acquires the state of the dolly, and
Based on the state of the trolley acquired by the state acquisition unit, the relative posture of the trolley with respect to the transport vehicle main body is detected, and the traveling of the transport vehicle main body is based on the relative posture of the trolley with respect to the transport vehicle main body. An autonomous carrier equipped with a control unit that controls speed.
The state acquisition unit is configured to acquire the state of the feature point of the bogie.
16. Autonomous carrier.
With a dolly
An autonomous carrier that tows the dolly and runs autonomously,
A control device for transmitting a command to the autonomous carrier is provided.
The autonomous transport vehicle is
A state acquisition unit that acquires the state of the dolly, and
Based on the state of the trolley acquired by the state acquisition unit, the relative posture of the trolley with respect to the transport vehicle main body is detected, and the traveling of the transport vehicle main body is based on the relative posture of the trolley with respect to the transport vehicle main body. A transport system, including a transport vehicle control unit that controls speed.
The state acquisition unit is configured to acquire the state of the feature point of the bogie.
15. Described transport system.