Automated carrying robot

Abstract

To provide an automated carrying robot that can accomplish a high carrying efficiency, and a method for carrying an object to be carried using the automated carrying robot.SOLUTION: An automated carrying robot includes: a drive mechanism; an ascending and descending unit configured to lift up an object to be carried; a tracking sensor which is located on a floor, and which is configured to detect a first guide line and a second guide line separated from each other; and a control unit. The control unit: controls the drive mechanism based on information from the tracking sensor in such a way that the automated carrying robot runs on the first guide line; detects a first marker located at an end of the first guide line; controls, after detecting the first marker, the drive mechanism in such a way that the automated carrying robot turns to the left or turns to the right; detects, after turning to the left or turning to the right, a second marker located at an end of the second guide line; and controls the drive mechanism in such a way that the automated carrying robot runs on the second guide line.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] One embodiment of the present invention relates to an automatic transport robot and a method for transporting an object to be transported using the automatic transport robot.

Background Art

[0002] In recent years, the technological development of automatic guided vehicles (AGVs) has advanced. For example, automatic transport robots for automatically transporting material carts (hereinafter simply referred to as carts) for transporting construction materials and the like at construction sites and building sites have been developed. For example, the automatic transport robots disclosed in Patent Documents 1 to 4 automatically travel in a state where the cart is lifted after getting under the cart or in a state where the cart is towed. By transporting materials while the automatic transport robot travels automatically, human resources for material transport can be saved.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Patent Document 2

Patent Document 3

Patent Document 4

Summary of the Invention

Problems to be Solved by the Invention

[0004] One of the embodiments of the present invention aims to provide an automatic transport robot with new functions and a method for transporting an object to be transported, such as a material, using the automatic transport robot. Alternatively, one of the embodiments of the present invention aims to provide an automatic transport robot capable of achieving high transport efficiency and a method for transporting an object to be transported using the automatic transport robot.

Means for Solving the Problem

[0005] One of the embodiments of the present invention is an automatic transport robot. This automatic transport robot includes a drive mechanism, a lifting unit, a following sensor, and a control unit. The lifting unit is configured to lift the object to be transported. The following sensor is located on the floor and is configured to detect a first guide line and a second guide line that are separated from each other. The control unit is configured to control the lifting unit. The control unit is further configured to, based on the information from the following sensor, (1) control the drive mechanism so that the automatic transport robot travels on the first guide line, (2) detect a first marker disposed at an end of the first guide line, (3) after detecting the first marker, control the drive mechanism so that the automatic transport robot turns left or right, (4) after turning left or right, detect a second marker disposed at an end of the second guide line, and (5) control the drive mechanism so that the automatic transport robot travels on the second guide line.

[0006] One embodiment of the present invention is a method for transporting an object to be transported using an automatic transport robot. This method includes lifting a cart on which the object to be transported is mounted using the automatic transport robot, and automatically driving the automatic transport robot on a first guide line provided on the floor based on information from a following sensor mounted on the automatic transport robot, detecting a first marker disposed at an end of the first guide line, turning the automatic transport robot left or right after detecting the first marker, detecting a second marker disposed at an end of a second guide line provided on the floor and separated from the first guide line after turning left or right, and automatically driving the automatic transport robot on the second guide line.

Brief Description of the Drawings

[0007]

Figure 1

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Figure 10A

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Embodiments for Carrying Out the Invention

[0008] Hereinafter, each embodiment of the present invention will be described with reference to the drawings and the like. However, the present invention can be implemented in various modes without departing from the gist thereof, and is not to be construed as being limited to the description of the embodiments illustrated below.

[0009] For the sake of clearer explanation, the drawings may schematically represent the width, thickness, shape, etc. of each part as compared with the actual embodiment, but this is merely an example and does not limit the interpretation of the present invention. In this specification and each figure, elements having the same functions as those described with respect to the previously presented figures may be denoted by the same reference numerals, and redundant descriptions may be omitted. This reference numeral is used when collectively representing a plurality of identical or similar structures, and a hyphen and a natural number are added after the reference numeral when individually representing them.

[0010] In this specification and the claims, the expression that two structures are "orthogonal" includes not only the state where the two structures intersect perpendicularly (90°), but also the state where they intersect at an angle of 90° ± 10°.

[0011] Hereinafter, a right turn means that the automatic transport robot 100 turns to the right while in a traveling state or a stopped state. The former is a right turn, and the latter is a right rotation. The angle of turning to the right is not limited to 90° and is arbitrarily selected. The same applies to a left turn.

[0012] 1. Configuration of the Automatic Transport Robot An automatic transport robot according to one embodiment of the present invention is a robot that can detect a guideline indicating a transport path provided in advance on the floor and can travel independently while following the guideline. This automatic transport robot is configured to travel while lifting a transport object. As a typical application example, there is a case where a trolley loaded with construction or construction materials as a transport object is transported inside a building such as a building or a factory. The building may be a completed building or a building under construction. For example, by utilizing the automatic transport robot during a time period when no work is performed by workers or when the number of workers is small, the necessary materials can be automatically transported to the required location before the work by workers starts or intensifies. Thereby, an increase in work efficiency can be achieved.

[0013] A schematic perspective view and a functional block diagram of the automatic transport robot 100 according to one embodiment of the present invention are shown in FIGS. 1 and 2, respectively. As shown in FIG. 1, the automatic transport robot 100 includes a housing 122, a lifting unit 106, a drive mechanism 108, a distance measuring sensor 114, a following sensor 116, and the like. Although not shown in FIG. 1, inside the housing 122, in addition to a control unit 102 that controls the automatic transport robot 100, a storage unit 104, a battery 118, a transmission / reception unit 120, etc. that are controlled by the control unit 102 are arranged.

[0014] (1) Control Unit The control unit 102 includes a processor such as a central processing unit (CPU), and controls the entire automatic transport robot 100 by controlling the storage unit 104, the lifting unit 106, the drive mechanism 108, the battery 118, the transmission / reception unit 120, and the like. The control unit 102 may be composed of a so-called microcomputer. The control unit 102 operates according to the instructions of a control program for controlling the automatic transport robot 100.

[0015] (2) Storage Unit The storage unit 104 may be a rewritable non-volatile memory such as a hard disk drive or a flash memory, or may be a volatile memory such as a static random access memory (SRAM) or a dynamic random access memory (DRAM). The storage unit 104 may be a combination of a non-volatile memory and a volatile memory. The storage unit 104 is configured to store a transport route transmitted from an external communication terminal (not shown). The storage unit 104 may be configured to store its own position and the transport destination of the transport object (i.e., the destination) as numerical values on the floor coordinates. Note that the control program may be incorporated in the control unit 102 or stored in the storage unit 104.

[0016] (3) Drive Mechanism The drive mechanism 108 is a module that provides the automatic transport robot 100 with a traveling function. In addition to a pair of crawlers 110 and drive wheels 112, it includes a motor (not shown) that rotates the drive wheels 112 by power supply from the battery 118. Based on information from the following-described follow-up sensor 116, the drive mechanism 108 is controlled by the control unit 102 not only to make the automatic transport robot 100 automatically travel along the transport path, but also to turn left or right to change the course from one transport path to another. In the example shown in FIG. 1, the automatic transport robot 100 travels by the crawlers 110. However, instead of the crawlers 110, a plurality of wheels that are in direct contact with the floor on which the automatic transport robot 100 travels, and a motor that rotates the plurality of wheels may be used as the drive mechanism 108.

[0017] Although not shown, the drive mechanism 108 includes an encoder in the housing 122 as a sensor for grasping the rotation speed (or rotational speed) and rotation direction of a pair of crawlers 110. Information from the encoder of the drive mechanism 108 is sent to the control unit 102, and the rotation speed and rotation direction of the pair of crawlers 110 or the wheels are constantly monitored. For example, the control unit 102 acquires the rotation speed and rotation direction of the crawlers 110 or the wheels from the drive mechanism 108 at regular time intervals (for example, 1 / 60 seconds or more and 1 second or less). The acquired rotation speed and rotation direction may be stored in the storage unit 104 as travel data. Further, the control unit 102 calculates the direction with respect to a specific point arbitrarily set, such as the travel start point, and the distance from the point based on the acquired rotation speed and rotation direction. In this way, by using the odometry realized by the encoder and the control unit 102, the position, orientation, and travel direction of the automatic transport robot 100 can be constantly grasped. These information may also be stored in the storage unit 104 at regular time intervals (for example, 1 / 60 seconds or more and 1 second or less).

[0018] (4) Lifting unit The lifting unit 106 is a mechanism that moves up and down according to the instructions of the control unit 102 and lifts the cart on which the object to be transported is mounted. The lifting unit 106 can be composed of a support member that contacts and supports the bottom surface of the cart, a motor that operates by receiving power supply from the battery 118, a hydraulic cylinder, and the like. As shown in FIGS. 3A and 3B, the cart 130 includes a loading platform 132 for mounting materials and the like, and a plurality of casters 134 provided under the loading platform 132. When the lifting unit 106 is in the lowest position, the automatic transport robot 100 is configured such that the height of the automatic transport robot 100 (the distance from the floor 152 on which the automatic transport robot 100 travels to the upper surface of the lifting unit 106) is lower than the lower surface of the loading platform 132. For this reason, the automatic transport robot 100 can sneak under the loading platform 132 in a state where the lifting unit 106 is in the lowest position. When the lifting unit 106 is raised in this state, as shown in FIG. 3B, the cart 130 is lifted by the automatic transport robot 100, and the cart 130 is in a state of floating from the floor 152. By running the automatic transport robot 100 in this state, the cart 130 and the materials and the like mounted thereon can be transported simultaneously.

[0019] (5) Transceiver The transceiver 120 is a module that is responsible for wireless communication with an external communication terminal (not shown), receives various instructions and information transmitted from the external communication terminal, and is configured to transmit this to the control unit 102. The transceiver 120 may be configured to cooperate with the control unit 102 and transmit position information including the position of the automatic transport robot 100 estimated by the control unit 102 to the external communication terminal. By providing the transceiver 120, the automatic transport robot 100 can be remotely operated via the external communication terminal. For example, the automatic transport robot 100 can be run toward an arbitrary location using the external communication terminal.

[0020] (6) Distance measuring sensor The distance measuring sensor 114 is configured to detect obstacles existing in the traveling direction of the automatic transport robot 100, as well as structures such as walls and pillars. There is no limitation to the distance measuring mechanism of the distance measuring sensor 114. For example, the distance measuring sensor 114 can be configured to emit electromagnetic waves such as laser light, infrared rays, radio waves, or ultrasonic waves in the traveling direction of the automatic transport robot 100, and detect the electromagnetic waves or ultrasonic waves reflected on the obstacle. By using the time from when the electromagnetic wave or ultrasonic wave is emitted until the electromagnetic wave or ultrasonic wave reflected on the obstacle is detected by the distance measuring sensor 114, the presence or absence of an obstacle and the distance to the obstacle can be measured. Alternatively, the distance measuring sensor 114 may be configured to calculate the distance based on the phase difference between the electromagnetic wave emitted after being amplitude modulated and the electromagnetic wave reflected on the obstacle. The range (detection range) in which the distance measuring sensor 114 detects an obstacle is appropriately set using the control unit 102.

[0021] When an obstacle is detected within the detection range, the control unit 102 stops the drive mechanism 108 and stops the automatic transport robot 100 according to the instructions of the control program. With this function, contact between the automatic transport robot 100, the carriage 130, or the object to be transported mounted on the carriage 130 and the obstacle is prevented, ensuring the safety of the operation and preventing damage to the automatic transport robot 100, the carriage 130, the object to be transported, etc. Also, even when the automatic transport robot 100 is in a state where it has detected an obstacle and stopped, it is configured to periodically determine the presence or absence of an obstacle based on the information from the distance measuring sensor 114, for example, at time intervals of 1 / 60 seconds or more and 1 second or less, and start traveling again when the obstacle is removed and not detected.

[0022] (7) Following sensor The automatic transport robot 100 is configured to travel on a guide line installed in advance on the floor 152. That is, the transport path of the automatic transport robot 100 is set in advance, and a guide line is arranged on the floor 152 along this transport path. The guide line is formed of a color tape or the like fixed to the floor 152 using a fixture such as an adhesive or a screw. The following sensor 116 is provided to detect the guide line.

[0023] The tracking sensor 116 acquires information for recognizing guidelines and markers and point markers described later. For this purpose, a digital optical camera can be used as the tracking sensor 116. The tracking sensor 116 is configured and arranged to acquire an image of the floor 152 under the automatic transport robot 100 together with an image in the traveling direction of the automatic transport robot 100. The image acquired by the tracking sensor 116 is analyzed by the control unit 102, and guidelines, markers, and point markers are detected by recognizing and extracting a region of a specific color from the image. The control unit 102 calculates the position of the guideline with respect to the automatic transport robot 100 and the angle between the traveling direction and the guideline, and controls the drive mechanism 108 so that the guideline overlaps the center of the automatic transport robot 100 and the angle between the traveling direction and the guideline remains 0°. In this way, by the control unit 102 controlling the drive mechanism 108 based on the information acquired by the tracking sensor 116, the automatic transport robot 100 can accurately travel on the guideline.

[0024] (8) Battery The battery 118 is a module that supplies power for the operation of the automatic transport robot 100. As the battery 118, a rechargeable secondary battery such as a lithium-ion battery, a lead-acid battery, a nickel-metal hydride battery, or a nickel-cadmium battery can be used. Although not shown, the automatic transport robot 100 may be configured so that the battery 118 is detachable from the housing 122.

[0025] (9) Other configurations Although not shown, the automatic transport robot 100 may be provided with other components such as a speaker and a warning light. The speaker may be configured to output a warning sound according to an instruction from the control unit 102 when the control unit 102 detects an obstacle in the detection range. Also, the speaker may be configured to output a sound different from the above warning sound during travel. The warning light may be configured to turn on according to an instruction from the control unit 102 when the control unit 102 detects an obstacle in the detection range. Also, the warning light may be configured to blink during travel. Furthermore, the automatic transport robot 100 may have an illumination device configured to irradiate a guide line with light. An optical camera is provided as a following sensor 116 for detecting a guide line of a color tape, but by using the illumination device, the guide line can be surely detected by the following sensor 116 without depending on the ambient brightness.

[0026] 2. Method for transporting an object to be transported using an automatic transport robot Hereinafter, a method for transporting an object to be transported using the automatic transport robot 100 will be described with reference to the flowchart shown in FIG. 4 and the like. Usually, since there are a variety of destinations for the object to be transported, a plurality of transport paths are constructed on the floor 152 on which the automatic transport robot 100 travels. Also, the transport paths may intersect each other. In the following description, as shown in FIG. 5, after the automatic transport robot 100 automatically travels on one transport path (first transport path) 154-1, a mode of traveling along the first transport path 154-1 without changing the course, and a mode of changing the course to a second transport path 154-2 intersecting the first transport path 154-1 will be described.

[0027] (1) Installation of guide line First, guidelines for indicating the conveyance path 154 are installed on the floor 152. When a plurality of conveyance paths 154 do not intersect with each other, one guideline may be installed for each conveyance path 154. On the other hand, when a plurality of conveyance paths 154 intersect, the guidelines indicating the intersecting conveyance paths 154 are separated from each other without intersecting. Specifically, as shown in FIG. 6, each of the first guideline 150-1 and the second guideline 150-2 corresponding to two mutually intersecting conveyance paths (the first conveyance path 154-1 and the second conveyance path 154-2) is installed so as to be separated via the intersection of the conveyance paths 154. Therefore, the intersection of the extension lines of the first guideline 150-1 and the second guideline 150-2 becomes the intersection of the conveyance paths 154, and neither the first guideline 150-1 nor the second guideline 150-2 exists at this intersection.

[0028] Furthermore, markers 156 are provided at the end portions on the intersection side of each of the first guideline 150-1 and the second guideline 150-2. That is, as shown in FIG. 6, first markers 156-1 are respectively installed at the end portions on the intersection side of the mutually separated first guideline 150-1. Similarly, second markers 156-2 are respectively installed at the end portions on the intersection side of the mutually separated second guideline 150-2. Each marker 156 has a color different from that of the corresponding guideline 150. For example, one may be blue and the other may be red. Therefore, the automatic conveyance robot 100 traveling on the guideline 150 can recognize a marker 156 having a color different from that of the guideline 150 before reaching the intersection by using the information obtained from the follow-up sensor 116. Note that the colors of the guidelines 150 forming the two intersecting conveyance paths 154 may be the same or different. Preferably, the color of one guideline 150 is the same as the color of the marker 156 of the other guideline 150, and the color of the other guideline 150 is the same as the color of the marker 156 of one guideline 150. Similar to the guideline 150, the marker 156 may also be fixed to the floor 152 using a fixing tool such as an adhesive or a screw, such as a colored tape.

[0029] Marker 156 has a linear shape orthogonal to the corresponding guideline 150, and the distance D between the markers 156 facing each other through the intersection of the conveyance path 154 is appropriately determined according to the size of the automatic conveyance robot 100. Specifically, the distance D is set to be at least twice the rotation radius when the automatic conveyance robot 100 rotates (spins) at the intersection of the conveyance path 154. By setting the distance D in this way, it is possible to prevent the drive mechanism 108 from stepping on the marker 156 when the automatic conveyance robot 100 rotates. As will be described later, after rotating at the intersection of the two conveyance paths 154, the automatic conveyance robot 100 travels autonomously in a state where the guideline 150 does not exist and detects the second marker 156-2. Therefore, it is preferable that the distance from the intersection to the marker 156 is small. Accordingly, the distance D is preferably set to be greater than twice the rotation radius and not more than three times the rotation radius.

[0030] The length L of the marker 156 may be appropriately set so that the automatic conveyance robot 100 can easily detect it even when the rotation angle at the intersection deviates from the angle between the two conveyance paths 154.

[0031] (2) Travel on the Guideline Next, place the cart 130 carrying the object to be transported, such as materials, on the first guide line 150-1 indicating the first transport path 154-1, and place the automatic transport robot 100 under the cart 130 (see FIGS. 3A, 3B, and 5). For example, transmit the positions of the automatic transport robot 100 and the cart 130 (coordinates on the floor 152) to the automatic transport robot 100. Thereby, the control unit 102 of the automatic transport robot 100 can grasp its own position and the position of the cart 130. Then, the control unit 102 uses the information from the follow sensor 116 to control the drive mechanism 108 so as to automatically travel along the first guide line 150-1 to the coordinates of the cart 130. Thereby, the automatic transport robot 100 can dive under the cart 130. Alternatively, the automatic transport robot 100 may be operated using an external communication terminal and moved under the cart 130. Alternatively, the automatic transport robot 100 may be manually placed under the cart 130. Alternatively, the automatic transport robot 100 may be first placed on the first guide line 150-1, and the cart 130 may be placed so as to overlap the automatic transport path robot.

[0032] Thereafter, use an external communication terminal to transmit the coordinates of the destination to the automatic transport robot 100. At this time, the coordinates of the departure point, the guide line 150 used, the marker 156, its color, order, etc. may also be transmitted to the automatic transport robot 100. The control unit 102 uses the information from the follow sensor 116 to control the drive mechanism 108 so as to travel on the guide line 150 to the transmitted coordinates of the destination. When the guide line 150 to be used and its order are specified, the control unit 102 controls the drive mechanism 108 so as to travel on the guide line 150 in the specified order. Thereby, the automatic transport robot 100 starts automatic travel on the guide line 150.

[0033] At this time, in order to detect obstacles, the information obtained from the distance measurement sensor 114 is used. Specifically, based on the information sent from the distance measurement sensor 114, the control unit 102 determines whether there are obstacles or structures in the detection range, and further calculates the distance to the obstacles or structures. When the distance to the obstacles or structures becomes less than a certain distance, the control unit 102 stops the drive mechanism 108 according to the instructions of the control program. At this time, a warning sound may be generated or a warning light may be activated. Also, when the obstacle is removed from the detection range, the control unit 102 may be configured to resume traveling.

[0034] (3) Detection of Markers As described above, the image acquired by the tracking sensor 116 is analyzed by the control unit 102, and a region of a specific color is recognized and extracted from the image. Therefore, when the automatic transport robot 100 approaches the intersection of the two transport paths 154 while detecting the guide line 150, it can detect a marker 156 of a color different from that of the guide line 150. That is, a first marker 156-1 that is different from the color of the first guide line 150-1 and orthogonal to the first guide line 150-1 is detected. If the first marker 156-1 is not detected, it means that there is a distance to the intersection of the transport path 154, so the automatic transport robot 100 maintains traveling on the guide line 150. However, if there is a large deviation between the distance from the starting point to the first marker 156-1 and the traveling distance obtained using odometry, for example, if the latter is 1.2 times or more of the former, there is a possibility that the automatic transport robot 100 is not traveling correctly on the first guide line 150-1. Therefore, the control unit 102 may stop the automatic transport robot 100, emit a warning sound, and / or turn on a warning light according to the instructions of the control program.

[0035] (4) Change of Transport Path When changing the conveyance path, that is, when turning right or left without going straight through the intersection, the control unit 102 controls the drive mechanism 108 to turn the automatic conveyance robot 100 to the left or right. Specifically, as shown in FIG. 7A, when the drive mechanism 108 has a pair of crawlers 110, after the control unit 102 detects the first marker 156-1, the control unit 102 controls the drive mechanism 108 so that the automatic conveyance robot 100 goes straight to the intersection. At this time, since there is no first guideline 150-1 between the first marker 156-1 and the intersection, the automatic conveyance robot 100 goes straight using the measurement result of the odometry. Since the distance D (see FIG. 6) is determined in advance and stored in the storage unit 104 or the control unit 102, the automatic conveyance robot 100 can reach the intersection using the measurement result of the odometry. Thereafter, the drive mechanism 108 rotates about the yaw axis (in this example, a 90° right rotation) according to the command from the control unit 102 (FIG. 7B). The rotation may be performed by rotating the pair of crawlers in opposite directions. Whether the rotation is completed is also determined using the odometry.

[0036] On the other hand, when the drive mechanism 108 is a wheel, after the control unit 102 detects the first marker 156-1, the control unit 102 does not let the automatic conveyance robot 100 go straight until it reaches the intersection, and controls the drive mechanism 108 to turn according to the distance D (FIG. 8A). Also in this case, the automatic conveyance robot 100 does not detect the first guideline 150-1 and turns using the measurement result of the odometry. Since the distance D is determined in advance and stored in the storage unit 104 or the control unit 102, the automatic conveyance robot 100 can turn (in this example, a 90° right turn) according to the turning radius (FIG. 8B).

[0037] After the rotation (or turning, the same applies hereinafter) is completed, the control unit 102 further controls the drive mechanism 108 so that the automatic transport robot 100 moves straight. When the control unit 102 detects the second guideline 150-2 having a preset color based on the information from the following sensor 116, the running continues along the second guideline 150-2. On the other hand, the case where the second guideline 150-2 cannot be detected means that the rotation angle at the intersection greatly deviates from the angle between the transport paths 154, or the straight-ahead distance after detecting the first marker 156-1 is excessive or insufficient. However, even if such a deviation occurs, since the marker 156 has a length L sufficiently larger than the width W of the guideline 150, the automatic transport robot 100 can detect the second marker 156-2. When the control unit 102 detects the second marker 156-2, it appropriately corrects the traveling direction based on the inclination with respect to the second marker 156-2 and travels a certain distance in a direction parallel to the second guideline 150-2. As a result, it becomes possible to detect the second guideline 150-2 within the detection range, so that the robot can travel along the designated transport path 154.

[0038] Note that when the control unit 102 cannot detect either the second marker 156-2 or the second guideline 150-2, the automatic transport robot 100 has deviated from the second transport path 154-2 and is running. Therefore, the control unit 102 generates an error notification and transmits the error notification to an external communication terminal via the transmission / reception unit 120. At this time, the control unit 102 may be configured to turn on a warning light or generate a warning sound.

[0039] (5) Straight movement When the conveyance path 154 is not changed, that is, when going straight through the intersection without turning right or left, after the control unit 102 detects the first marker 156-1, the control unit 102 controls the drive mechanism 108 to maintain straight running until the automatic conveyance robot 100 passes through the intersection and detects the opposing first marker 156-1 and / or the first guideline 150-1 (FIGS. 9A and 9B). The measurement result of odometry is also used during the running until the first marker 156-1 and / or the first guideline 150-1 is detected. For this reason, the automatic conveyance robot 100 does not necessarily run straight accurately. However, as described above, since the marker 156 has a length L sufficiently larger than the width W of the guideline 150, the automatic conveyance robot 100 can surely detect the first marker 156-1. Therefore, by running in a direction parallel to the first guideline 150-1 while appropriately correcting the traveling direction based on the inclination with respect to the first marker 156-1, the first guideline 150-1 can be captured within the detection range. As a result, running on the first guideline 150-1 can be continued.

[0040] Running on the guideline 150 is continued until the destination is reached. When the automatic conveyance robot 100 further goes straight, turns left, or turns right at the next intersection, the above-described procedure may be repeated. After arriving at the destination, the control unit 102 stops the drive mechanism 108, lowers the lifting unit 106, and places the carriage 130 on the floor. Thereby, the conveyance of the object to be conveyed is completed.

[0041] (6) Modified Example In the conveying method according to the embodiment of the present invention, the angle between the two intersecting conveying paths 154 and the guideline 150 indicating the same is not limited to 90°, and as shown in FIG. 10A, it can be set at any angle. Alternatively, as shown in FIG. 10B, one or both of the intersecting conveying paths 154 may be bent at the intersection. In these cases, the angle between the conveying paths 154 and the length L of the marker 156 are appropriately set so that the markers 156 do not intersect each other or the marker 156 and the guideline 150 do not intersect. Also, as shown in FIGS. 11A and 11B, the two conveying paths 154 and the guideline 150 indicating the same may form an L-shaped path or a T-shaped path. Even when the two conveying paths 154 form an L-shaped path or a T-shaped path, the guideline 150 is not installed between the marker 156 and the intersection.

[0042] When the drive mechanism 108 has the crawlers 110, a point marker 158 may be installed at the intersection of the two conveying paths 154 (FIG. 11C). Similar to the guideline 150, the point marker 158 may also be fixed to the floor 152 using a fixing tool such as an adhesive or a screw for a color tape or the like. The point marker 158 may be configured by combining, for example, two color tapes having different colors. For example, a point marker 158 may be formed by crossing a red color tape and a blue color tape. Alternatively, a point marker 158 may be formed using a single-color color tape. The shape of the point marker 158 is also arbitrary and may be a cross, a circle, a polygon including a triangle or a quadrilateral, a star shape, or the like. However, the size of the point marker 158 is set so that the diameter of the circle (the dotted circle in FIG. 11B) inscribed therein is equal to or less than the distance between the pair of crawlers 110. By adopting the above size, it is possible to prevent the pair of crawlers 110 from coming into contact with the point marker 158 when the automatic conveyance robot 100 rotates, and thus it is possible to prevent damage to the point marker 158.

[0043] By installing the point marker 158 and detecting it with the automatic transport robot 100, even if the automatic transport robot 100 moves straight using odometry after detecting the marker 156, it can accurately reach the intersection. Alternatively, the deviation from the intersection can be calculated, and the rotation angle and the straight - ahead direction after rotation can be corrected. In addition, by transmitting the color, shape, etc. of the point marker 158 from an external communication terminal to the automatic transport robot 100 in advance, it becomes possible to more reliably detect the point marker 158.

[0044] As described above, typical examples of the objects to be transported are construction and engineering materials, and although it also depends on the size of the cart 130, their weight may exceed several hundred kg. When the automatic transport robot 100 crosses the guideline 150 while carrying such a heavy object, a large horizontal force is applied to the guideline 150 due to the friction with the drive mechanism 108. In particular, when the automatic transport robot 100 rotates or turns at the intersection of the transport path 154, a very large force is applied on the locus 160 (see Fig. 10) on the floor 152 of the drive mechanism 108, so the guideline 150 is easily damaged. When the guideline 150 is damaged, the automatic transport robot 100 cannot recognize the guideline 150, so the automatic transport robot 100 cannot run automatically. This causes a significant reduction in the transport efficiency.

[0045] However, as described above, in the transport method using the automatic transport robot 100 according to one embodiment of the present invention, when changing the transport path 154, markers 156 facing each other at a distance D are installed via the intersection of the transport paths 154 that cross each other. Furthermore, the guideline 150 is not arranged between the marker 156 and the intersection. Therefore, when the automatic transport robot 100 rotates, the drive mechanism 108 is prevented from passing over the guideline 150, and damage to the guideline 150 can be prevented.

[0046] Also, although the guideline 150 is not provided at the intersection of the conveyance path 154, a marker 156 having a length L sufficiently larger than the width W of the guideline 150 is provided at the end of the guideline 150. For this reason, even when a deviation occurs in the traveling direction due to an odometry measurement error, or when the rotation angle or turning angle deviates from the angle between the conveyance paths 154, the marker 156 can be easily detected and used to correct the traveling direction. Therefore, it is possible to prevent abnormal situations such as the automatic conveyance robot 100 deviating from the conveyance path 154 when going straight on the intersection or changing the conveyance path 154, or the automatic conveyance robot 100 stopping due to deviation from the conveyance path 154. This contributes to the realization of highly efficient conveyance work.

[0047] The various embodiments described above as embodiments of the present invention can be implemented in appropriate combination as long as they do not conflict with each other. Based on each embodiment, those in which those skilled in the art appropriately add, delete, or change the design of components are also included in the scope of the present invention as long as they have the gist of the present invention.

[0048] Even for other operational effects different from those brought about by the above-described embodiments, those that are obvious from the description in this specification or can be easily predicted by those skilled in the art are naturally understood to be brought about by the present invention.

Explanation of Reference Numerals

[0049] 100: Automatic conveyance robot, 102: Control unit, 104: Storage unit, 106: Lifting unit, 108: Drive mechanism, 110: Crawler, 112: Driving wheel, 114: Distance measuring sensor, 116: Tracking sensor, 118: Battery, 120: Transmission and reception unit, 122: Housing, 130: Cart, 132: Loading platform, 134: Caster, 150: Guideline, 150-1: First guideline, 150-2: Second guideline, 152: Floor, 154: Conveyance path, 154-1: First conveyance path, 154-2: Second conveyance path, 156: Marker, 156-1: First marker, 156-2: Second marker, 158: Point marker, 160: Locus

Claims

1. A drive mechanism, A lifting unit configured to lift an object to be transported, A following sensor located on the floor and configured to detect a first guide line and a second guide line that are separated from each other, and An automatic transport robot comprising a control unit configured to control the lifting unit, The control unit is further configured to, based on information from the following sensor, Control the drive mechanism so that the automatic transport robot travels on the first guide line, Detect a first marker disposed at an end of the first guide line, After detecting the first marker, control the drive mechanism so that the automatic transport robot turns left or right, After turning left or right, detect a second marker disposed at an end of the second guide line, and Control the drive mechanism so that the automatic transport robot travels on the second guide line. An automatic transport robot configured to perform the above.

2. The first marker has a color different from that of the first guide line and has a linear shape orthogonal to the first guide line, The second marker has a color different from that of the second guide line and has a linear shape orthogonal to the second guide line. The automatic transport robot according to claim 1.

3. The first guide line and the second marker have a first color, The second guide line and the first marker have a second color. The automatic transport robot according to claim 1.

4. The control unit is further configured to control the drive mechanism so that the automatic transport robot travels straight to the intersection of the extension lines of the first guide line and the second guide line after detecting the first marker. The automatic transport robot according to claim 1.

5. The control unit is further configured to control the drive mechanism so that the automatic transport robot rotates about the yaw axis at the intersection. The automatic transport robot according to claim 4.

6. The control unit is further configured to control the drive mechanism so that the automatic transport robot travels straight until the second marker is detected after turning left or right. The automatic transport robot according to claim 1.

7. The control unit is further configured to Detecting a point marker located at the intersection of the extension lines of the first guideline and the second guideline based on the information from the tracking sensor. The automatic transport robot according to claim 1, configured to execute controlling the drive mechanism so that the automatic transport robot turns left or right after detecting the point marker.

8. A method for automatically transporting an object to be transported using an automatic transport robot, the method comprising: Lifting a cart on which the object to be transported is mounted using the automatic transport robot, and Based on the information from a tracking sensor mounted on the automatic transport robot, Automatically driving the automatic transport robot on a first guideline provided on the floor, Detecting a first marker disposed at an end of the first guideline, After detecting the first marker, turning the automatic transport robot left or right, After turning left or right, detecting a second marker disposed at an end of a second guideline provided on the floor and separated from the first guideline, and Automatically driving the automatic transport robot on the second guideline.

9. The first marker has a color different from that of the first guideline and has a linear shape orthogonal to the first guideline. The method according to claim 8, wherein the second marker has a color different from that of the second guideline and has a linear shape orthogonal to the second guideline.

10. The first guideline and the second marker have a first color. The method according to claim 8, wherein the second guideline and the first marker have a second color.

11. The method according to claim 8, further comprising automatically driving the automatic transport robot straight ahead to the intersection of the extension lines of the first guideline and the second guideline after detecting the first marker.

12. The method according to claim 11, turning the automatic transport robot left or right at the intersection.

13. The method according to claim 11, further comprising driving the automatic transport robot straight ahead until detecting the second marker after turning left or right.

14. Detecting a point marker located at the intersection of the extension lines of the first guideline and the second guideline based on the information from the tracking sensor, and The method according to claim 11, further comprising turning the automatic transport robot left or right after detecting the point marker.

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