Unmanned transport vehicles, unmanned transport systems and transport procedures

Abstract

Provided are an unmanned transport vehicle, an unmanned transport system, and a transport program that can dock with a cage vehicle in a position and posture that is advantageous for transport. The unmanned transport vehicle of an embodiment comprises: a mobile body that can autonomously travel on the ground and has a docking portion for coupling with a transport object; and a first detection sensor that can detect the support legs of the transport object. The mobile body has a height that allows it to enter a bottom space surrounded by the lower surface of a cargo plate of the transport object, a plurality of the support legs, and the ground.

Description

[0001] This application is based on Japanese Patent Application No. 2021-047512 (filing date: March 22, 2021) and claims priority from the aforementioned application, the entire contents of which are incorporated herein by reference. Technical Field

[0002] Embodiments of the present invention relate to an unmanned guided vehicle, an unmanned transport system, and a transport program. Background Art

[0003] In the field of logistics, there is a desire to save manpower due to a shortage of manpower and cost reduction. There is also a great expectation for automation of cage handling operations in logistics warehouses, distribution centers, etc., and efforts are being made to save manpower by using unmanned guided vehicles such as AGVs that were previously used in factory production lines to lift cages or transport them by hook. In recent years, unmanned guided vehicles with self-position estimation functions have also appeared, greatly improving the freedom of movement. Here, all mobile carts with a handling function are referred to as unmanned guided vehicles.

[0004] As mentioned above, unmanned guided vehicles are becoming more popular, but regarding their transportation methods, in general, special cages that match the shape of the unmanned guided vehicle are prepared, or markers such as RF tags and 2D bar codes are embedded in the floor, etc., and there are many cases where processing is performed on the environment other than the unmanned guided vehicle, making it difficult to transport commercially available standard cages as is.

[0005] One reason for this is that it is difficult to popularize detection and motion control of general-purpose cage trucks using automated guided vehicles during docking.

[0006] In recent years, there is a technology that uses "proximity data and navigation data from a wireless communication device" to guide an automated guided vehicle to dock with the caster portion of a wheelchair as a docking object.

[0007] For example, the Amazonroboticskiva (registered trademark) transport robot prepares a dedicated transport frame that matches the robot's vehicle height. After the transport frame is accurately set to a predetermined position in advance, the robot moves while confirming the position identification tag embedded in the ground, thereby achieving accurate docking with the transport frame.

[0008] In general, in the logistics industry, general-purpose cage pallets called roll box pallets (RBP) are widely used, and there is a high demand for automatic transport vehicles that can autonomously detect cage pallets and transport without processing the cage pallets or environmental equipment.

[0009] However, in the existing robot system as mentioned above, the transport object and the moving environment need to be modified. It is difficult to realize the detection and docking of the cage truck by only preparing a transport truck.

[0010] Therefore, there is a technology that uses camera images and deep learning to detect and dock cage trucks, but the measurement accuracy of the transported object in units of pixels based on image processing is low, making it difficult to dock in a position and posture that is advantageous for transportation. Summary of the invention

[0011] The problem to be solved by the present invention is to provide an unmanned transport vehicle, an unmanned transport system, and a transport program that can dock with a cage vehicle in a position and posture that is advantageous for transport.

[0012] An embodiment provides an unmanned guided vehicle, the unmanned guided vehicle comprising: a moving body capable of autonomously traveling on the ground and having a docking portion for engaging with a transported object; and a first detection sensor capable of detecting a support leg of the transported object. The moving body has a height capable of entering a bottom space surrounded by a lower surface of a cargo plate of the transported object, a plurality of the support legs, and the ground.

[0013] An embodiment provides an unmanned transport system for transporting objects based on the unmanned transport vehicle involved in the present invention, the unmanned transport system comprising: a step of using a first detection sensor to detect the entry side support legs of the transport object; a step of detecting the positions of a pair of entry side support legs in the transport object based on the detection result of the first detection sensor, and calculating an entry target reference point that is the target of the entry position for the transport object and a docking target position that is the target of the docking position for the transport object; a step of causing the mobile body to move in stages from the entry target reference point to the docking target position; and a step of causing the unmanned transport vehicle to dock with the transport object.

[0014] An embodiment provides a procedure for transporting an object to be transported by the above-mentioned unmanned guided vehicle of the present invention, wherein the procedure causes a computer system to perform the following processing: using a first detection sensor to detect an entry side support leg of the transported object, detecting the position of a pair of entry side support legs in the transported object based on the detection result of the first detection sensor, calculating an entry target reference point that is a target for the entry position toward the transported object and a docking target position that is a target for the docking position with respect to the transported object, causing the moving body to move in stages from the entry target reference point to the docking target position, and causing the unmanned guided vehicle to dock with the transported object. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1This is a perspective view showing a usage example of the automated guided vehicle according to the first embodiment.

[0016] Figure 2 It is a plan view showing the sizes of the automated guided vehicle and the cage vehicle according to the first embodiment.

[0017] Figure 3 It is a side view showing the sizes of the automated guided vehicle and the cage vehicle according to the first embodiment.

[0018] Figure 4 This is a diagram showing a control flow chart of the control device in the automated guided vehicle according to the first embodiment.

[0019] Figure 5 It is a plan view showing the object inspection range of the automated guided vehicle according to the first embodiment.

[0020] Figure 6 This is a diagram showing an example of an object detection map that visualizes the detected positions of objects.

[0021] Figure 7 It is a plan view showing an example of the operation of the automated guided vehicle based on the detection position of the casters of the cage vehicle.

[0022] Figure 8 This is a diagram showing a control flowchart of another operation example of the automated guided vehicle.

[0023] Fig. 9 It is a diagram for explaining another operation example of the automated guided vehicle.

[0024] Fig.10 The figure shows the positional relationship between the first entry target reference point (M') and the first docking target position (G') set according to the type of the entry-side caster (rotatable type) and the ideal entry target reference point (M) and docking target position (G).

[0025] Fig.11 The figure shows the positional relationship between the first entry target reference point (M') and the first docking target position (G') set according to the type of the entry-side caster (fixed rotation axis type) and the ideal entry target reference point (M) and docking target position (G).

[0026] Fig.12 It is a diagram showing a configuration of an automated guided vehicle according to a second embodiment and an example of its operation.

[0027] Fig.13 This is a diagram showing a control flowchart of an operation example of the automated guided vehicle 230 according to the second embodiment.

[0028] Fig.14 It is a plan view showing an example of operation to be solved when the automated guided vehicle according to the third embodiment is used.

[0029] Fig.15 It is a plan view showing a preferred operation example of the automated guided vehicle according to the third embodiment.

[0030] Fig.16 This is a diagram showing a control flow chart of a control device in the automated guided vehicle according to the third embodiment.

[0031] Fig.17 It is a perspective view for explaining the structure and operation of the automated guided vehicle according to the fourth embodiment.

[0032] Fig.18 It is a plan view for explaining the structure and operation of the automated guided vehicle according to the fourth embodiment.

[0033] Fig.19 It is a diagram showing a control flow chart of a control device in the automated guided vehicle according to the fourth embodiment. DETAILED DESCRIPTION

[0034] Hereinafter, an unmanned guided vehicle, an unmanned guided vehicle system, and a guided vehicle program according to an embodiment will be described with reference to the drawings, and repeated descriptions of these configurations may be omitted.

[0035] In addition, "based on XX" in this application means "at least based on XX", and also includes the case where it is based on other elements in addition to XX. In addition, "based on XX" is not limited to the case where XX is used directly, but also includes the case where the result is obtained by calculating and processing XX. "XX" is an arbitrary element (for example, arbitrary information).

[0036] In this application, the X direction, Y direction, and Z direction of the orthogonal coordinate system are defined as follows. The Z direction is the vertical direction, and the +Z direction is the upward direction. The X direction is the horizontal direction, which is the front-to-back direction of the unmanned guided vehicle, and the +X direction is the front direction of the unmanned guided vehicle. The Y direction is the horizontal direction, which is the direction orthogonal to the X direction, and is the left-right direction (width direction) of the unmanned guided vehicle.

[0037] In addition, the automated guided vehicle can move in at least the X direction and rotate, but is not limited thereto, and can also move in the Y direction, or in a combination of the Y direction and other directions.

[0038] In this specification, an unmanned guided vehicle is a vehicle that moves a cage car to another place. The direction of the unmanned guided vehicle to transport (tow) the cage car is set as "front", and the direction facing the docked cage car is set as "rear". In addition, the action of moving the unmanned guided vehicle in the -X direction ("rear") toward the cage car is set as "entry action relative to the cage car", and the action of moving in the +X direction ("front") is set as "action of transporting (tow) the cage car".

[0039] (First embodiment)

[0040] Figure 1 It is a perspective view showing a usage example of the automated guided vehicle 200 according to the first embodiment. Figure 2 It is a plan view showing the sizes of the automated guided vehicle and the cage vehicle according to the first embodiment. Figure 3 It is a side view showing the sizes of the automated guided vehicle and the cage vehicle according to the first embodiment.

[0041] The unmanned guided vehicle 200 of this embodiment is, for example, a lineless type transport vehicle that can travel autonomously without requiring operation by an operator or lines drawn on the ground. The unmanned guided vehicle 200 is, for example, a low-floor type transport vehicle that sneaks under the cage vehicle 100 and connects (docking) with the cage vehicle 100 to transport the cage vehicle 100 to another location.

[0042] However, the unmanned guided vehicle 200 in the present invention is not limited to the above example, and may be other types of guided vehicles. For example, the unmanned guided vehicle 200 may be a guided vehicle whose autonomous moving parts other than docking operations are controlled by an operator.

[0043] First, the structure of the cage vehicle (transport object) 100 as the transport object of the automated guided vehicle 200 will be described.

[0044] Figure 1 The structure of the cage vehicle 100 shown is an example.

[0045] The cage vehicle 100 includes a pallet 101 on which cargo can be loaded, a frame member 102 vertically erected from four sides of the pallet 101 , and four casters (support legs) 103 provided at four corners on the lower surface 101 b side of the pallet 101 .

[0046] The four casters 103 are all rotatable casters, which can move the cage trolley 100 in all directions. Figure 2 In FIG. 1 , the rotation range of each caster 103 is indicated by a dotted circle.

[0047] In addition, at least two of the four casters 103 may be of a type that can switch between freely rotatable and fixed rotation axes as appropriate. In addition, all four casters 103 may be fixed rotation axis casters.

[0048] like Figure 1 and Figure 3 As shown, there is a bottom space K surrounded by the ground F, four casters 103, and the lower surface 101b of the cargo plate 101 at the bottom of the cage vehicle 100. The automated guided vehicle 200 enters into the bottom space K.

[0049] Next, the structure of the automated guided vehicle 200 in the first embodiment will be described in detail.

[0050] The automated guided vehicle 200 includes a transport vehicle body (mobile body) 201 , a plurality of wheels 202 , a plurality of wheel drive motors (not shown) that respectively drive the wheels 202 , a first detection sensor (detection sensor) 210A, and a control device 220 .

[0051] In this embodiment, the control device 220 uses a computer system having a processor and a memory as a main structure. The processor of the computer system executes the transfer program involved in the present invention recorded in the memory of the computer system, thereby realizing the functions of the control device 220. The transfer program can be recorded in the memory, provided via a telecommunication line such as the Internet, or recorded in a non-temporary recording medium such as a memory card.

[0052] The transport vehicle body 201 has a first portion 201A that is rectangular in a plan view and a second portion 201B that extends upward from one side in the length direction of the first portion 201A. The first portion 201A is a portion that can be inserted under the cage vehicle 100. Inside the first portion 201A, a wheel drive motor, a sensor, a battery, a control device (none of which are shown in the figure), etc. are mounted.

[0053] In addition, the transport vehicle body 201 in the present embodiment may be constituted by only the first portion 201A.

[0054] The transport vehicle body 201 has a docking portion 203 for docking with the cage vehicle 100. The docking portion 203 includes an elevator (not shown) provided in the first portion 201A and a top plate 204 that can move up and down together with the elevator. The unmanned guided vehicle 200 raises the elevator while at least the first portion 201A of the transport vehicle body 201 is submerged under the cage vehicle 100, and the top plate 204 contacts the lower surface 101b of the cargo plate 101 of the cage vehicle 100, thereby docking with the cage vehicle.

[0055] Two wheels 202 are installed on each side of the transport vehicle body 201 in the width direction (short direction: Y direction) in a top view. The two wheels 202 installed on one side are arranged at intervals in the length direction (X direction) of the first portion 201A, and are installed at the same position in the length direction of the transport vehicle body 201 as the other two wheels 202 installed on the other side, and the wheels on both sides in the width direction of the transport vehicle body 201 face each other. These four wheels 202 have axles parallel to the width direction.

[0056] The four wheels 202 are configured as Mecanum wheels that can move in any direction. The Mecanum wheel has a plurality of rollers on the circumference of the wheel 202. The rollers rotate freely around a rotation axis that is inclined 45 degrees relative to the axle of the wheel 202. Each wheel 202 of the Mecanum wheel structure is provided with a wheel drive motor and an encoder. By changing the combination of the rotation directions and the rotation speed of the four wheels 202, the transport vehicle 201 can be moved in all directions.

[0057] The wheel drive motor and encoder provided in each wheel 202 are provided in, for example, the first portion 201A in the transport vehicle body 201 .

[0058] The rotation speed of the wheel drive motor detected by the encoder (hereinafter referred to as encoder information) can be directly or indirectly taken into the control device 220 via a motor driver, etc. Thus, the control device 220 can continuously measure the rotation speed of each wheel 202 at any time. The control device 220 controls the rotation speed of each wheel 202 at any time according to each encoder information, and rotationally drives the four wheels 202 independently of each other.

[0059] The unmanned guided vehicle 200 of this embodiment is an omnidirectional mobile mechanism with Mecanum wheels. Therefore, the unmanned guided vehicle 200 can rotate and drive each wheel 202 by a separate drive motor through a program pre-programmed into the storage unit of the control device 220, and can operate autonomously in an unmanned state.

[0060] In addition, a sensor capable of measuring the rotation speed, such as a Hall sensor, may be used instead of the encoder. In addition, the four wheels 202 may be either a conventional two-wheel independent drive system (two drive wheels and two driven wheels) or a steering wheel system known as an active caster.

[0061] In addition, the unmanned guided vehicle 200 of the present embodiment is an omnidirectional mobile vehicle using Mecanum wheels, but is not limited thereto and may be other omnidirectional mobile mechanisms such as omni wheels. Alternatively, an independent two-wheel drive system or other system may be used to control a non-holonomic mobile mechanism in accordance with the constraints on its freedom of movement.

[0062] In addition, a communication function may be provided to transmit sensor information, movement information of the transport vehicle 201 , and the like to a system outside the transport vehicle 201 , so that a part of the processing of the control device 220 can be shared using external resources.

[0063] like Figure 2 and Figure 3 As shown, the unmanned guided vehicle 200 of this embodiment is structured to dock with the cage vehicle 100 in a state where a portion of the transport vehicle body 201 (the first portion 201A) is inserted under the cargo plate 101 of the cage vehicle 100, and thus has a size corresponding to the cage vehicle 100 to be transported. Here, it is preferably a size corresponding to multiple types of existing cage vehicles 100.

[0064] like Figure 2 As shown, when the caster spacing between a pair of entry-side casters 103a (103) located on the side where the unmanned guided vehicle 200 is to enter among the four casters 103 of the cage car 100 is set to Cw, the first part 201A of the transport vehicle body 201 has a body width W (Cw>W) that is sufficiently narrow compared to the spacing Cw between the entry-side casters 103a.

[0065] Thus, when at least one pair of the entry-side casters 103 a is rotatable, the automated guided vehicle 200 can sneak under the cage vehicle 100 without interfering with the cage vehicle 100 regardless of the rotation direction of the pair of entry-side casters 103 a .

[0066] In addition, if Figure 3 As shown in FIG. 1 , when the height from the ground F on which the cage car 100 is placed to the lower surface 101b of the cargo board 101 in the cage car 100 is set to CH, the transport body 201 of the unmanned guided vehicle 200 has a body height H lower than the lower surface 101b of the cargo board 101 of the cage car 100 (CH>H). As a result, in the unmanned guided vehicle 200, the first portion 201A of the transport body 201 can enter the bottom space K under the cage car 100 without interfering with the cargo board 101 of the cage car 100 ( Figure 1 , Figure 3 )Inside.

[0067] Thus, the automated guided vehicle 200 according to the present embodiment can allow at least the entire first portion 201A of the transport vehicle body 201 to be submerged under the cage vehicle 100 .

[0068] The first detection sensor 210A is a side area sensor that measures the distance in a spatial plane by laser scanning. Examples of side area sensors include a laser range finder (LRF: Laser Range Finger) and a light radar (LiDAR: Light (Imaging) Detection and Ranging). Figure 1 , a laser scanning range R1 of the first detection sensor 210A is shown.

[0069] also, Figure 1 The laser scanning range R1 shown in FIG. 1 is an example and is actually a wider range.

[0070] In this embodiment, the distance to the cage vehicle 100 as the transport object can be measured. The first detection sensor 210A is attached to the rear end surface 201c of the transport vehicle 201 so that the projection direction of the laser beam is rearward (-X direction) of the transport vehicle 201.

[0071] Here, the rear of the transport vehicle body 201 refers to the direction in which the automated guided vehicle 200 moves toward the cage vehicle 100. That is, the automated guided vehicle 200 of this embodiment is as follows: Figure 1 As shown in the figure, the first detection sensor 210A is installed on the rear end face 201c side of the transport vehicle 201 to move backward in the -X direction (rearward) toward the cage vehicle 100. The first detection sensor 210A is located approximately in the center of the rear end face 201c in the width direction (Y direction) of the transport vehicle 201.

[0072] The laser scanning surface of the first detection sensor 210A is horizontal and lower than the lower surface 101b of the cargo plate 101 of the cage vehicle 100, and is fixed at a height capable of detecting each caster 103 of the cage vehicle 100. The first detection sensor 210A is provided at a height position of the caster 103 of the cage vehicle 100, so that it faces the caster 103 in the horizontal direction and does not detect the cargo plate 101 of the cage vehicle 100, etc.

[0073] The first detection sensor 210A can measure the Figure 1 The laser scanning range R1 of the first detection sensor 210A is, for example, a range where the maximum projection angle θ is 270°. ° The first detection sensor 210A can detect the presence or absence of an object in the laser scanning range R1 based on the presence or absence of reflection of the laser. The projection light reaching distance in the laser scanning range R1 is, for example, about 15 m.

[0074] The first detection sensor 210A can detect the distance and azimuth to the object by using the degree of reflection of the irradiated laser. The first detection sensor 210A outputs data indicating the presence or absence of the object, the distance and azimuth to the object. In the following description, the output of the first detection sensor 210A is referred to as a "measurement value".

[0075] The number of the first detection sensor 210A is not limited to 1, and sufficient number can be set to ensure necessary visual field. In addition, the location of the first detection sensor 210A is not limited to the rear end face 201c of the transport vehicle body 201, and can be installed in other appropriate places and with other appropriate postures.

[0076] In addition, the first detection sensor 210A is not limited to the above example, and may be other types of sensors. For example, the first detection sensor 210A may also use other high-precision distance sensors such as a 3D LIDER. In this case, a certain plane in the 3D scanning space of the LIDER is made consistent with the projection surface of the first detection sensor 210A.

[0077] The control device 220 includes a computer having a processor such as a CPU, a memory, and a storage medium, and can execute software. The control function of the control device 220 is realized by software.

[0078] The control device 220 of the present embodiment includes an object detection map generation unit 221 that generates an object detection map based on detection data of the first detection sensor 210A and the like.

[0079] In addition, the control device 220 has a motion control unit that has an inverse kinematics (IK) processing function that converts the rotational angular velocity of each wheel axle into a translational velocity and a rotational angular velocity with arbitrary directions and magnitudes at a representative position of the unmanned guided vehicle 200 (here, the center position of the unmanned guided vehicle 200 (the portion where the XYZ coordinate system is placed)), and a forward kinematics (DK) processing function that converts the translational velocity and the rotational angular velocity of the representative position of the unmanned guided vehicle 200 into a rotational angular velocity corresponding to the rotational velocity of each wheel axle.

[0080] The motion control unit controls the wheel drive motors etc. based on the detection data acquired from the first detection sensor 210A etc. The motion control unit can control the moving speed of the automated guided vehicle 200 and can control the transport speed of the automated guided vehicle 200 at any timing.

[0081] The motion control unit has a self-position estimation function based on the time integration (dead reckoning) of the translation speed and rotation angular velocity of the transport vehicle 201 obtained by the forward kinematics processing mechanism (DK) and matching of the object detection map using the detection distance information (LRF information) of the first detection sensor 210A.

[0082] Furthermore, the motion control unit has a position control function (global movement) that generates a path from the current location to the target location based on the object detection map generated in the object detection map generation unit 221 and can reach the target location while following the generated path. The distance measurement unit used to obtain the detection distance information at this time is not limited to being shared with the first detection sensor 210A, and a distance measurement unit dedicated to the motion control unit may also be installed separately at any position and posture.

[0083] Next, an operation example (transportation system example) of the automated guided vehicle 200 will be described.

[0084] Figure 4 This is a diagram showing a control flow chart of the control device in the automated guided vehicle according to the first embodiment. Figure 5 It is a plan view showing the object inspection range of the automated guided vehicle according to the first embodiment. Figure 6 This is a diagram showing an example of an object detection map that visualizes the detected positions of objects. Figure 7 It is a plan view showing an example of the operation of the automated guided vehicle based on the detection position of the casters of the cage vehicle.

[0085] Reference Figure 4 , Figure 6 as well as Figure 7 , along Figure 5 The control flow chart of the control device 220 shown in FIG.

[0086] The control device 220 of the activated automated guided vehicle 200 first executes step S0 .

[0087] In step S0 , the control device 220 initializes the first detection sensor 210A and then starts controlling the automated guided vehicle 200 .

[0088] Next, the control device 220 executes step S1.

[0089] In step S1, the control device 220 uses the position control function (global movement) of the motion control unit to autonomously move the automated guided vehicle 200 to the vicinity of the cage vehicle 100 to be transported. The control device 220 drives the four wheels 202 individually to move the automated guided vehicle 200 to the vicinity of the cage vehicle 100 to be transported.

[0090] In this embodiment, docking from the long side of the cage vehicle 100 is taken as an example for explanation. Figure 5 As shown, the automated guided vehicle 200 is moved to the front of the long side of the cage vehicle 100. When the automated guided vehicle 200 docks with the cage vehicle 100 from other directions, the global movement destination may be set to another position. For example, the global movement destination may be set to the front of the short side of the cage vehicle 100.

[0091] Next, the control device 220 executes step S2.

[0092] In step S2, the control device 220 performs a detection by the first detection sensor 210A. The control device 220 projects a laser from the first detection sensor 210A toward the cage vehicle 100, detects an object in the surrounding environment of the plane space within the laser scanning range R1, and measures the distance to the surface of the detected object. The control device 220 obtains the detection point group data of the object within the laser scanning range R1.

[0093] As an object detected by the first detection sensor 210A, Figure 5 As shown, not only the casters 103 of the cage cart 100 existing in the plane space within the laser scanning range R1 but also the surrounding environmental structures such as the wall 91 and the pillar 92 at the same height as the casters 103 are detected simultaneously with the casters 103. In one detection operation, the purpose is to obtain the detection point group data of at least the caster 103a located on the long side where the automated guided vehicle 200 docks (hereinafter referred to as the entry side caster 103a) among the four casters 103 of the cage cart 100.

[0094] Next, the control device 220 executes step S3.

[0095] In step S3 , the control device 220 detects the direction of the cage vehicle 100 and the type of the caster 103 .

[0096] First, the control device 220 aggregates the detection point groups that are densely packed in a range close to the size of the caster 103 of the cage vehicle 100 from the plurality of object detection point group data acquired via the first detection sensor 210A into one cluster information, and regards it as a point group group 111 ( Figure 5 In the present embodiment, the point group 111 closest to the automated guided vehicle 200 is regarded as entering the side caster 103a.

[0097] The shape pattern of the point group 111 that changes due to the size of the caster 103 and the posture (rotation direction) of the caster 103 is stored in advance in the storage unit of the control device 220. Therefore, the control device 220 compares the shape pattern of the point group stored in the storage unit with the shape pattern of the point group 111 actually acquired, and determines the point group 111 of the caster 103 of the cage vehicle 100 to be transported from the object detection point group data based on their matching, and determines whether the caster 103 detected by the point group 111 is a freely rotatable type or a fixed rotation axis type, and determines the direction of the cage vehicle 100 to be transported based on the type of the detected caster 103 and its caster posture.

[0098] Here, a learning process such as deep learning may be used for matching with the shape pattern of the point cloud group 111 stored in the storage unit of the control device 220 .

[0099] In addition, in the case of performing operations in advance such as placing the cage car 100 at a predetermined location on the ground F, the detection range of the caster 103 based on the first detection sensor 210A may not be the entire detection range (laser scanning range R1) of the first detection sensor 210A. In other words, pattern matching may not be performed on all point group groups detected in the detection range (laser scanning range R1) of the first detection sensor 210A, but only the detection points included in the area (hereinafter referred to as the nearby area A) where the cage car 100 is presumed to exist may be used as caster inspection objects. In this way, the risk of false detection of areas other than the caster 103 can be reduced, and the computational processing load required for detection can be reduced. In addition, Figure 6 and Figure 7 The illustrated vicinity A is represented by a rectangular shape along the outer shape of the cage vehicle 100 , but the range of the defined vicinity A is not limited to the rectangular shape.

[0100] Next, the control device 220 executes step S4.

[0101] In step S4, the control device 220 determines that the side caster 103a has entered.

[0102] As the point group 111 detected by the first detection sensor 210A, a maximum of four casters 103 may be detected from one cage vehicle 100 depending on the size of the detection range (laser scanning range R1).

[0103] In addition, when other cage carts 100 that are not the objects of transportation are arranged on the ground F in addition to the cage cart 100 that is the object of transportation, according to the size of the detection range (laser scanning range R1) of the first detection sensor 210A, it is possible to detect the casters 103 of the other cage carts 100 that are within the detection range (laser scanning range R1).

[0104] Therefore, in step S4, the control device 220 Figure 6 As shown, the global movement is achieved until the vicinity of the cage vehicle 100 to be transported, and the two point group groups 111a closest to the first detection sensor 210A are regarded as a pair of entry-side casters 103a on the side of the cage vehicle 100 to be transported.

[0105] Next, the control device 220 executes step S5.

[0106] In step S5, the control device 220 calculates the entry target reference point M of the automated guided vehicle 200. Figure 7 As shown, representative positions O (here, the center positions of the casters 103) in a pair of entry-side casters 103a are determined based on the two point groups 111a. Here, the control device 220 regards the center of gravity positions of the two point groups 111a detected by the first detection sensor 210A as the center positions of the entry-side casters 103a. The control device 220 calculates the midpoint of the first straight line LN connecting the representative positions O of the entry-side casters 103a as the entry target reference point M of the automated guided vehicle 200.

[0107] Here, the entry target reference point M refers to a point that becomes a target when the automated guided vehicle 200 enters toward the cage vehicle 100 .

[0108] Next, the control device 220 executes step S6.

[0109] In step S6 , the control device 220 calculates the docking target position G.

[0110] The control device 220 is as follows Figure 7 As shown, the direction along the second straight line LM orthogonal to the first straight line LN at the entry target reference point M as the midpoint of the first straight line LN is set as the travel direction (reverse direction) of the unmanned guided vehicle 200, and the docking target position G for the cage car 100 is calculated with reference to the geometric information (known) such as the size of the cage car 100 and the unmanned guided vehicle 200 and the predetermined docking entry amount (predetermined value) to the cage car 100. At this time, the docking target position G is preferably located at the bottom space K ( Figure 1 , Figure 3 ) and is aligned with or near the center of gravity of the cage vehicle 100 in the Z direction (up and down direction).

[0111] Here, the docking target position G refers to a target position for docking with respect to the cage vehicle 100 .

[0112] Next, the control device 220 executes step S7.

[0113] In step S7, the control device 220 causes the unmanned guided vehicle 200 to enter the bottom space K under the cage vehicle 100. The control device 220 drives each wheel 202 to move the transport vehicle body 201 toward the cage vehicle 100 in the -X direction (backward). At this time, the control device 220 causes the transport vehicle body 201 to move along the first straight line LN so that the first portion 201A of the transport vehicle body 201 enters the bottom space K under the cage vehicle 100 to be transported. The control device 220 stops the unmanned guided vehicle 200 at the docking target position G ( Figure 7 At this time, the center of gravity position of the automated guided vehicle 200 and the docking target position G of the cage vehicle 100 are preferably aligned in the Z direction (vertical direction).

[0114] Next, the control device 220 executes step S8.

[0115] In step S8, the control device 220 performs the docking operation with the cage vehicle 100. The control device 220 raises the elevator of the docking unit 203 in the unmanned guided vehicle 200 at the docking target position G, so that the top plate 204 connected to the elevator contacts the lower surface 101b of the cargo plate 101 of the cage vehicle 100. In this way, the docking operation with the cage vehicle 100 is completed.

[0116] Thereafter, the control device 220 shifts to an operation of moving the transport vehicle body 201 toward a predetermined transport destination to transport the cage vehicle 100 .

[0117] Thus, according to the unmanned guided vehicle 200 of this embodiment, the casters 103a on the entry side of the cage cart 100 can be detected and moved toward the docking target position calculated based on their positions and types, so that the cage cart 100 can be docked at a position (accurate position) and posture that are advantageous for transporting the cage cart 100. Here, the position and posture that are advantageous for transporting refer to a position and posture that achieves a good docking balance.

[0118] The unmanned guided vehicle 200 of this embodiment does not require processing of the cage vehicle 100 or environmental equipment, so detection and docking of the cage vehicle 100 to be transported can be achieved by simply preparing the unmanned guided vehicle 200, so it has high versatility and can suppress costs.

[0119] In addition, in the above embodiment, the operation examples corresponding to multiple types of existing cage carts 100 are described, but it is not necessary to execute all the above operation steps. For example, if the type and state of the corresponding cage cart 100 (castor 103) are known in advance, step S3 can be omitted.

[0120] Hereinafter, another operation example (transportation system example) of the automated guided vehicle 200 will be described.

[0121] Here, the unmanned guided vehicle 200 located at a position separated from the cage car 100 is not moved straight forward to the docking target position G. Instead, on the entry side of the cage car 100, after being moved to a position facing the unmanned guided vehicle 200 (movement passing point P), it is moved in stages through the entry target reference point M to the docking target position G.

[0122] Figure 8 2 is a diagram showing a control flowchart of another operation example of the automated guided vehicle 200 . Fig. 9 It is a diagram for explaining another operation example of the automated guided vehicle 200 .

[0123] Fig. 9 The control device 220 of the automated guided vehicle 200 shown in FIG. Figure 8 Steps S10 to S16 are performed as shown. Steps S10 to S16 in the control flow of this embodiment are different from those in the first embodiment described above. Figure 4 Steps S0 to S6 shown are the same, so their description is omitted.

[0124] Next, the control device 220 executes step S17.

[0125] In step S17, the control device 220 determines whether the automated guided vehicle 200 needs to move through the point P. Before the automated guided vehicle 200 moves to the final moving target position (docking target position G) calculated in step S16, the control device 220 executes step S17 according to Fig. 9 The positional relationship between the automated guided vehicle 200 and the cage car 100 at the initial moving position shown by the imaginary line is used to determine whether it is necessary to move through the point P between the current position of the automated guided vehicle 200 and the cage car 100.

[0126] That is, when the control device 220 uses the position control function (global movement) of the motion control unit to move to the vicinity of the cage car 100 to be transported, it is determined whether the unmanned guided vehicle 200 can be directly moved from the current position to the docking target position G for the cage car 100 based on the positional relationship between the unmanned guided vehicle 200 and the cage car 100. Then, when it is determined whether a moving passing point P is required between the current position of the unmanned guided vehicle 200 and the cage car 100, the moving passing point P is determined between the entry target reference point M of the cage car 100 and the unmanned guided vehicle 200.

[0127] Here, the moving passing point P is a position where the automated guided vehicle 200 can directly move to the docking target position G.

[0128] Next, the control device 220 executes step S18.

[0129] In step S18, the control device 220 determines the moving passing point P and moves the AGV 200. When the control device 220 determines in the previous step S17 that the AGV 200 cannot move straight from the current position to the docking target position G without interfering with the casters 103 of the cage vehicle 100 and needs to determine the moving passing point P, the control device 220 determines the moving passing point P. Fig. 9 As shown, a moving point P is determined at a position in front of the cage vehicle 100 in the direction along the second straight line LM. Then, the automated guided vehicle 200 is moved toward the determined moving point P. The control device 220 first moves the automated guided vehicle 200 to the moving point P before moving the automated guided vehicle 200 to the docking target position G by executing steps S17 to S18.

[0130] Next, the control device 220 executes step S19.

[0131] In step S19 , the control device 220 causes the automated guided vehicle 200 located at the moving passing point P to enter under the cage vehicle 100 and move to the docking target position G.

[0132] Afterwards, the control device 220 executes step S19A to perform a docking operation on the cage vehicle 100 at the docking target position G.

[0133] As described above, the control device 220 may also execute the step-by-step movement procedure in such a manner that the automated guided vehicle 200 moves to the docking target position G after moving to the moving passing point P. Thus, no matter where the automated guided vehicle 200 starts the docking operation, it can smoothly complete the docking operation with the cage vehicle 100 without contacting the casters 103 of the cage vehicle 100.

[0134] (Second embodiment)

[0135] Fig.10 The figure shows the positional relationship between the first entry target reference point (M') and the first docking target position (G') set according to the type of the entry-side caster, and the ideal entry target reference point (M) and the docking target position (G). Fig.11 The figure shows the positional relationship between the first entry target reference point (M') and the first docking target position (G') set according to the type of the entry-side caster (fixed rotation axis type) and the ideal entry target reference point (M) and docking target position (G). Fig.12 2 is a diagram showing the structure of the unmanned guided vehicle 230 according to the second embodiment and an example of its operation. Fig.12 The laser scanning ranges R1 and R2 shown in the figure are examples and are actually wider ranges.

[0136] Here, first, the relationship between the posture of the automated guided vehicle when the movement is completed and the ideal posture when docking with respect to the cage cart 100 will be described according to the caster type of the cage cart 100 .

[0137] The movement accuracy of the automated guided vehicle during docking may vary depending on the type of casters 103 of the cage vehicle 100. The accuracy may vary depending on whether at least the pair of entry-side casters 103a of the cage vehicle 100 are rotatable or fixed-axis casters.

[0138] In the case where the four casters 103 in the cage vehicle 100 are of a freely rotatable type, Fig.10 As shown, the postures of all casters 103 are often different from each other. Therefore, the postures of the pair of entry-side casters 103a are also likely to be different from each other, and the first entry target reference point M' and the first docking target position G' calculated based on the representative position O of each entry-side caster 103a deviate from the ideal docking target position G (for example, the center position of the cage car 100). In this case, the posture of the unmanned guided vehicle when the movement is completed, that is, the posture when it reaches the docking target position G, is likely to be different from the ideal posture of the unmanned guided vehicle at the docking target position G.

[0139] On the other hand, Fig.11As shown, when at least a pair of entry-side casters 103a on the AGV side of the cage car 100 is of a fixed-rotation axis type, the postures of the pair of entry-side casters 103a are consistent with each other and there is no posture change. Therefore, the first entry target reference point M' calculated based on the representative position O of each entry-side caster 103a of the fixed-rotation axis type and the direction of the second straight line LM perpendicular to the first straight line LN at the first entry target reference point M' can be estimated to be consistent with the center line of the cage car 100. Therefore, the first entry target reference point M' and the first docking target position G' calculated based on the representative position O of the pair of entry-side casters 103a of the fixed-rotation axis type can both be designated as the ideal entry target reference point M and the docking target position G. Therefore, the posture of the AGV when the movement is completed, that is, the posture of the AGV when it reaches the docking target position G, is roughly consistent with the ideal posture of the AGV at the docking target position G.

[0140] Based on the above, an automated guided vehicle 230 according to the second embodiment will be described.

[0141] The unmanned guided vehicle 230 of this embodiment is as follows Fig.12 The embodiment shown is different from the first embodiment in that a plurality of detection sensors are provided.

[0142] The unmanned guided vehicle 230 of this embodiment has two detection sensors 210A and 210B. The pair of detection sensors 210A and 210B can measure the distance to the surface of an object in the surrounding environment of the plane space within the respective laser scanning ranges R1 and R2. The laser scanning ranges R1 and R2 of these detection sensors 210A and 210B are, for example, a maximum of 270 ° range.

[0143] The first detection sensor 210A is provided at the rear end face 201c of the transport vehicle body 201 in the unmanned guided vehicle 230, and the second detection sensor (detection sensor) 210B is provided at the side end face 201d on one side in the width direction of the transport vehicle body 201. The first detection sensor 210A is located at the approximate center of the rear end face 201c in the width direction, and the second detection sensor 210B is located at the approximate center of the side end face 201d in the width direction.

[0144] The laser scanning surfaces of the first detection sensor 210A and the second detection sensor 210B are horizontal and lower than the lower surface 101b of the cargo plate 101 of the cage vehicle 100, and are fixed at a height that can measure each caster 103 of the cage vehicle 100. The first detection sensor 210A and the second detection sensor 210B are provided at the same height as the caster 103 in the cage vehicle 100 in the Z direction, so that the cargo plate 101 of the cage vehicle 100 and the like are not detected.

[0145] The second detection sensor 210B is not limited to the position shown in the figure, but may be located at any other position as long as the secondary detection portion (the back side caster 103b) of the cage vehicle 100 to be transported can be detected satisfactorily.

[0146] The unmanned guided vehicle 230 of this embodiment is suitable for transporting a cage vehicle 100 having a mixture of freely rotatable casters 103 and fixed-rotation-axis casters 103. Fig.12 In the illustrated cage vehicle 100 of the transport object, a pair of casters 103 (103a, 103b) located on one short side of the cage vehicle 100 among the four casters 103 are mutually rotatable, and a pair of casters 103 (103a, 103b) located on the other short side are mutually fixed with respect to the rotation axis. Therefore, one of the pair of entry-side casters 103a located on the long side where the unmanned guided vehicle 230 enters in the cage vehicle 100 is a rotatable type, and the other is a fixed-axis type, and one of the pair of depth-side casters 103b located on the depth side of the cage vehicle 100 is a rotatable type, and the other is a fixed-axis type.

[0147] Next, an operation example (transportation system example) of the automated guided vehicle 230 according to the second embodiment will be described.

[0148] Fig.13 This is a diagram showing a control flowchart of an operation example of the automated guided vehicle 230 according to the second embodiment.

[0149] Here, the description Fig.12 The unmanned guided vehicle 230 of the present embodiment shown in the figure enters the bottom space K ( Figure 1 , Figure 3 ) is an example of the action in the case of

[0150] The control device 220 of the automated guided vehicle 230 is first Fig.13 Steps S20 to S22 are executed as shown. Steps S20 to S22 are the same as steps S0 to S2 in the first embodiment, and thus their description is omitted.

[0151] Next, the control device 220 executes step S23.

[0152] In step S23, the control device 220 detects the direction of the cage vehicle 100 and the type of the caster 103a on the entry side based on the detection result of the first detection sensor 210A. First, the control device 220 aggregates the detection point groups that are densely packed in a range close to the size of the caster 103 of the cage vehicle 100 from all the object detection point group data detected by the first detection sensor 210A into one group information, and regards it as a point group group 111 detected from one caster 103.

[0153] The control device 220 determines the point group 111 of the caster 103 in the cage truck 100 that is the transport object from the object detection point group data based on the matching of the shape pattern with the point group 111 stored in the storage unit, and determines the type of the caster 103 (freely rotating type or fixed rotating axis type) based on the point group 111.

[0154] Next, the control device 220 executes step S24.

[0155] In step S24, the control device 220 determines that the two point groups 111a detected at the position closest to the automated guided vehicle 230 are a pair of entry-side casters 103a (one of which is a freely rotatable type and the other of which is a fixed-axis type) located on the docking side of the cage vehicle 100 to be transported.

[0156] Next, the control device 220 executes step S25.

[0157] In step S25 , the control device 220 calculates a first entry target reference point M′ of the automated guided vehicle 230 based on the detected representative positions O of the pair of entry-side casters 103 a .

[0158] Next, the control device 220 executes step S26.

[0159] In step S26 , the control device 220 calculates a first docking target position G′ for the cage vehicle 100 based on the first entry target reference point M′ calculated in the previous step S25 .

[0160] Next, the control device 220 executes step S27.

[0161] In step S27, the control device 220 first causes the unmanned guided vehicle 230 to enter the bottom space K under the cage vehicle 100. The control device 220 causes the unmanned guided vehicle 230 to move toward the first entry target reference point M' calculated in the previous step S25, toward -X (backward), and enter under the cage vehicle 100. At this time, the unmanned guided vehicle 230 is caused to enter until the position of the detection sensor 210B mounted on the unmanned guided vehicle 230 at least exceeds the position of the entry-side caster 103a.

[0162] Next, the control device 220 executes step S28.

[0163] In step S28, the control device 220 performs a secondary search using the second detection sensor 210B. For example, while the control device 220 moves the unmanned guided vehicle 230 to the docking target position G, the control device 220 projects a laser from the second detection sensor 210B toward one side of the cage vehicle 100 in the Y direction (width direction) (here, the right side of the traveling direction of the unmanned guided vehicle 200), and searches for a pair of casters 103 on the side different from the entry side (the right side of the traveling direction) of the cage vehicle 100. At this time, at least the caster 103a on the entry side on the right side of the traveling direction of the cage vehicle 100 is detected, and the caster 103b on the depth side on the right side of the traveling direction is searched.

[0164] In this way, the control device 220 causes the unmanned guided vehicle 200 to enter under the cage vehicle 100, and uses the second detection sensor 210B to perform detection of a pair of casters 103 (deep side casters 103b) on one side in the Y direction (width direction). When another (a total of two) detection point group data regarded as casters 103 is newly detected at a position closest to the unmanned guided vehicle 200 in the plane space within the laser operation range R2, the control device 220 determines that the deep side casters 103b are detected.

[0165] Next, the control device 220 executes step S29.

[0166] In step S29, the control device 220 corrects the posture of the automated guided vehicle 230. The control device 220 obtains a fourth straight line L4 orthogonal to the third straight line L3 at the midpoint of the third straight line L3 connecting the representative position O of the caster 103a on the entry side and the representative position O of the caster 103b on the depth side detected by the second detection sensor 210B, calculates the ideal docking target position G based on this fourth straight line L4, and corrects the posture of the automated guided vehicle 230 at the docking target position G'. For example, Fig.11 As shown, for example, the AGV 230 is rotated counterclockwise in the figure to correct the posture in which the side of the AGV 230 is parallel to the side of the cage vehicle 100. Thus, the posture of the AGV 230 at the docking target position G can be set to a posture suitable for transportation.

[0167] Furthermore, if there is a deviation from the translation component of the target position G, this is also corrected.

[0168] Afterwards, the control device 220 executes step S29A to perform a docking operation on the cage vehicle 100 at the docking target position G.

[0169] According to the second embodiment, the unmanned guided vehicle 230 is provided with two detection sensors 210A and 210B. Therefore, after the detection sensor 210A is used to detect the position of the casters on the entry side (primary detection) before entering the cage vehicle 100, the detection sensor 210B is used to detect the casters on the depth side (secondary detection) after entering the cage vehicle 100, so that the posture of the unmanned guided vehicle 230 located at the docking target position G' calculated by the primary detection can be corrected to the ideal final posture at the docking target position G calculated by the secondary detection. In this way, the posture of the unmanned guided vehicle 230 is appropriately corrected not only according to the type (posture and position) of the casters 103a on the entry side of the cage vehicle 100, but also according to the type (posture and position) of the casters 103b on the depth side, so that the unmanned guided vehicle 230 can be docked with the cage vehicle 100 having a mixture of freely rotatable casters and fixed-rotation-axis casters 103 in an ideal posture. Thereby, regardless of the type of the casters 103 of the cage cart 100, the cage cart 100 can be appropriately transported.

[0170] Furthermore, although the type and arrangement direction of the cage vehicle 100 are known, the unmanned guided vehicle itself may have an identification function that can independently identify the type and arrangement direction of the cage vehicle 100. In addition, a notification function such as providing information about the cage vehicle from a host server such as the integrated management unmanned guided vehicle 230 may be used.

[0171] (Third embodiment)

[0172] Next, an automated guided vehicle 240 according to a third embodiment will be described.

[0173] Fig.14 It is a plan view showing an example of operation to be solved when the automated guided vehicle 240 according to the third embodiment is used. Fig.15 2 is a top view showing a preferred operation example of the unmanned guided vehicle 240 according to the third embodiment. Fig.15 The laser scanning range shown in (the range indicated by the dotted line) is an example and is actually a wider range.

[0174] The structure of the automated guided vehicle 240 will be described below.

[0175] like Fig.14 As shown, the unmanned guided vehicle 240 of this embodiment can transport the elongated cage vehicle 140. Here, docking from the short side of the cage vehicle 140 is taken as an example for description.

[0176] The elongated cage cart 140 to be transported has a cargo pallet 101 that is rectangular in shape when viewed from above and has a length in one direction, a pair of entry-side casters 103a arranged on one short side that are freely rotatable, and a pair of depth-side casters 103b arranged on the other short side that are fixed on the rotating axis.

[0177] The unmanned guided vehicle 240 of this embodiment has a transport vehicle body 201 that is rectangular in shape when viewed from above and has a length in one direction. The width of the transport vehicle body 201 along the short direction is set to a width W that is narrower than the interval Cw between the rotation ranges of a pair of freely rotatable entry-side casters 103a disposed on the short side of the cage vehicle 140. The length of the long direction of the unmanned guided vehicle 240 (the first portion 201A of the transport vehicle body 201) is preferably longer than or approximately equal to the length of the long direction of the cage vehicle 140.

[0178] Next, an operation example (transportation system example) of the automated guided vehicle 240 will be described.

[0179] Fig.16 This is a diagram showing a control flow chart of a control device in the automated guided vehicle according to the third embodiment.

[0180] Description Fig.15 The illustrated automated guided vehicle 240 of the present embodiment is an operation example in which the automated guided vehicle 240 enters from between a pair of rotatable entry-side casters 103 a disposed on the short sides of the cage vehicle 140 .

[0181] Fig.15 The control device 220 of the unmanned guided vehicle 240 shown in FIG. Fig.16 Steps S30 to S34 are executed. Steps S30 to S34 are the same as steps S0 to S4 in the first embodiment, and thus their description is omitted.

[0182] Next, the control device 220 executes step S35.

[0183] In step S35 , the control device 220 calculates the first entry target reference point M′ of the automated guided vehicle 230 based on the detected representative positions of the pair of rotatable entry-side casters 103 a .

[0184] Next, the control device 220 executes step S36.

[0185] In step S36 , the control device 220 calculates a first docking target position G′ for the cage vehicle 100 based on the first entry target reference point M′ calculated in the previous step S35 .

[0186] Next, the control device 220 executes step S37.

[0187] In step S37, the control device 220 first moves the automated guided vehicle 230 toward the first entry target reference point M' calculated in the previous step S35, and enters the bottom space K ( Figure 1 , Figure 3 )Inside.

[0188] Next, the control device 220 executes step S38.

[0189] In step S38, the control device 220 performs a secondary detection by the first detection sensor 210A. For example, while the control device 220 moves the unmanned guided vehicle 230 to the first docking target position G', the control device 220 projects a laser from the first detection sensor 210A toward the side (+Y direction) of the cage vehicle 100 to detect the casters 103 in a direction different from the entry direction of the cage vehicle 100. Here, the positions of the entry-side casters 103a and the depth-side casters 103b located on one side in the width direction of the cage vehicle 140 are detected.

[0190] Next, the control device 220 executes step S39.

[0191] In step S39, the control device 220 obtains the first entry target reference point M" which is the midpoint of the fourth straight line L4 connecting the representative positions of the casters 103b on the depth side detected by the first detection sensor 210A, and calculates the new docking target position G" (G) based on the fifth straight line L5 and the geometric information of the unmanned guided vehicle 230 and the cage car 100, and corrects the posture of the unmanned guided vehicle 240 entering under the cage car 100.

[0192] That is, when the pair of entry-side casters 103a of the cage vehicle 140 are rotatable, the first docking target position G′ calculated based on the positions of the rotatable entry-side casters 103a (primary search result) often deviates from the ideal docking target position G.

[0193] On the other hand, the second docking target position G" calculated based on the position of the depth-side caster 103b with a fixed rotating shaft (secondary detection result) is roughly consistent with the ideal docking target position G, so the second docking target position G" (G) calculated based on the secondary detection result should be set as a target to correct the posture of the unmanned guided vehicle 240 entering under the cage car 100. In this way, the unmanned guided vehicle 200 reaches the ideal docking target position G.

[0194] Furthermore, if there is a deviation from the translation component of the target position G, this is also corrected.

[0195] Next, the control device 220 performs docking with the cage vehicle 100 (step S39A).

[0196] As mentioned above, when using Fig.14 When the unmanned guided vehicle 240 of the present embodiment shown in the figure is used to transport the elongated cage 140, when the unmanned guided vehicle 240 is made to enter from the short side of the cage 140, if the entry side casters 103a are of the type with a fixed rotation axis, the postures of the entry side casters 103a do not change with each other, so the entry target reference point M and the docking target position G can be calculated with good accuracy based on the result of one detection. Therefore, the unmanned guided vehicle 240 can enter in a state where the longitudinal direction of the cage 140 is set to be substantially parallel, so the risk of collision (contact) between the unmanned guided vehicle 240 and the casters 103 (for example, the depth side casters 103b) of the cage 140 is low.

[0197] On the other hand, when the entry-side casters 103a are rotatable, the postures of the pair of entry-side casters 103a are likely to be different from each other. Therefore, when the unmanned guided vehicle 240 enters between the pair of rotatable entry-side casters 103a toward the first docking target position G' calculated based on the representative positions O of the pair of rotatable entry-side casters 103a (the second straight line LM perpendicular to the first straight line LN at the midpoint of the first straight line LN connecting the representative positions O (the first entry target reference point M')), the unmanned guided vehicle 240 is likely to collide (contact) with the cage car 140.

[0198] That is, the cage vehicle 140 is slender in shape, so it cannot ensure sufficient space with the automated guided vehicle 240 in the lateral width direction. Therefore, during the movement of the automated guided vehicle 240, for example, the front end side of the transport vehicle body 201 may contact the caster 103b on the rear side.

[0199] In contrast, according to the unmanned guided vehicle 240 of the present embodiment, when transporting a cage vehicle 140 having a rotatable entry-side caster 103a, the control device 220 moves the unmanned guided vehicle 240 toward the first entry target reference point M' calculated based on the primary detection result and enters under the cage vehicle 140 from between a pair of rotatable entry-side casters 103a, as shown in FIG. Fig.15 As shown, while the unmanned guided vehicle 240 is moved closer to the -X direction (rear) of the cage car 140, a secondary detection is performed by the first detection sensor 210A to detect the position of the depth side caster 103b. Thus, a new second docking target position G" (G) is calculated based on the relative positions of the depth side casters 103b with fixed rotation axes (based on the secondary detection results), and the travel direction of the unmanned guided vehicle 240 is appropriately corrected, so that the unmanned guided vehicle 240 can reach the ideal docking target position G.

[0200] In addition, the caster configuration information on the inner side of the cage vehicle 100 is known or can be obtained from the outside as described above. In addition, when the caster 103b on the inner side is re-detected after entering the cage vehicle 140, the detection range can be set to a range that is narrowed to a certain extent based on the caster configuration information of the detection area.

[0201] In addition, when the measuring distance of the first detection sensor 210A is long enough to determine the posture and type of all casters 103 in the cage truck 140 of the transport object and its measurement accuracy is high enough, a pair of depth side casters 103b with fixed rotating shafts can also be detected in one detection, and the docking target position G can be calculated based on the positions of these depth side casters 103b.

[0202] However, when the rear side caster 103b is located in a blind spot of the entry side caster 103a and is hidden, it is preferable not to perform the exploration of the rear side caster 103b in one exploration but to switch to the exploration of the entry side caster 103a.

[0203] (Fourth embodiment)

[0204] Next, an automated guided vehicle 250 according to a fourth embodiment will be described.

[0205] Fig.17 It is a perspective view for explaining the structure and operation of the automated guided vehicle according to the fourth embodiment. Fig.18 1 is a top view for explaining the structure and operation of the unmanned guided vehicle according to the fourth embodiment. Fig.17 , Fig.18 The laser scanning range shown (the range indicated by the dotted line) is an example and is actually a wider range.

[0206] The structure of the automated guided vehicle 250 will be described below.

[0207] The unmanned guided vehicle 250 of the present embodiment is a guided vehicle suitable for transporting a cage vehicle 100 in which all four casters are swivel casters.

[0208] like Fig.17 and Fig.18 As shown, the automated guided vehicle 250 in the present embodiment includes a pair of detection sensors (a first detection sensor 210A and a third detection sensor 210C) installed at different heights.

[0209] The third detection sensor (detection sensor) 210C is located on the upper surface 201a of the first portion 201A in the transport body 201 of the automated guided vehicle 250 and is provided so as to be in contact with the upper surface 201a of the first portion 201A and the front surface 201b of the second portion 201B.

[0210] The position of the laser projection surface of the third detection sensor 210C is higher than the lower surface 101b of the cargo plate 101 of the cage vehicle 100 and lower than the upper surface 101a of the cargo plate 101, and is opposite to the entry side end surface 101c of the cargo plate 101. The third detection sensor 210C detects the edge (side edge) of the cargo plate 101 from the position of the entry side end surface 101c of the cargo plate 101.

[0211] Next, an operation example (transportation system example) of the automated guided vehicle 250 according to the fourth embodiment will be described.

[0212] Fig.19 1 is a diagram showing a control flow chart of the control device 220 in the automated guided vehicle 250 according to the fourth embodiment.

[0213] Fig.18 The control device 220 of the automated guided vehicle 250 shown in FIG. Fig.19 Steps S40 to S42 are executed as shown. Steps S40 to S42 in the control flow of this embodiment are different from those in the first embodiment described above. Figure 4 Steps S0 to S2 shown are the same, so their description is omitted.

[0214] Next, the control device 220 executes steps S43 to S46 to calculate the first entry target reference point M' and the first docking target position G' based on the detection result of the first detection sensor 210A (the posture and orientation of the entry-side caster 103a).

[0215] Next, the control device 220 executes step S47.

[0216] In step S47 , the control device 220 causes the automated guided vehicle 250 to move forward.

[0217] In step S47 , the control device 220 causes the automated guided vehicle 250 to retreat in the −X direction toward the first entry target reference point M′, thereby bringing the automated guided vehicle 250 closer to the cage vehicle 100 .

[0218] Next, the control device 220 executes step S48.

[0219] In step S48 , the control device 220 performs secondary detection using the third detection sensor 210C. The control device 220 performs secondary detection using the third detection sensor 210C to detect the edge (entry side end surface 101 c ) of the pallet 101 of the cage vehicle 100 .

[0220] At this time, the approximate position of the edge of the pallet 101 can be searched by narrowing the range to a certain extent based on known shape information of the cage vehicle 100 .

[0221] In addition, in the detection of the edge of the pallet 101, the straight line detection process may be used for the detection point group information of the third detection sensor 210C.

[0222] Next, the control device 220 executes step S49.

[0223] In step S49, the control device 220 corrects the posture of the unmanned guided vehicle 250. The control device 220 calculates a new docking target position G on the sixth straight line L6 perpendicular to the entry side end face 101c at the midpoint in the length direction of the entry side end face 101c of the cargo pallet 101 detected in the previous step S48 (the second entry target reference point M”), and corrects the first docking target position G' calculated based on the caster position in the previous step S46.

[0224] Next, the control device 220 executes step S50.

[0225] In step S50, the control device 220 causes the automated guided vehicle 250 to further enter the bottom space K ( Figure 1 , Figure 3 In step S50, the control device 220 causes the automated guided vehicle 250 to further retreat in the -X direction and enter under the cage vehicle 100, and move to the docking target position G.

[0226] Next, the control device 220 executes step S51.

[0227] In step S51 , the control device 220 performs a docking operation of the automated guided vehicle 250 with respect to the cage vehicle 100 .

[0228] Thus, according to the unmanned guided vehicle 250 of the present embodiment, the docking target position G can be corrected before the unmanned guided vehicle 250 enters under the cage vehicle 100, so the traveling direction of the unmanned guided vehicle 250 can be corrected with a smaller movement. As a result, the unmanned guided vehicle 250 can move straight toward the ideal docking target position G, and the docking efficiency with the cage vehicle 100 is improved.

[0229] Furthermore, when the ground F and the posture of the automated guided vehicle 250 before entering are ideally prepared, the primary detection by the first detection sensor 210A (step S42) and the actions based on the primary detection (steps S43 to S46) may be omitted, and a secondary detection by the third detection sensor 210C may be performed.

[0230] The installation position of the third detection sensor 210C is not limited to the position shown in the figure, but may be any other position as long as it can satisfactorily detect the entry side edge of the pallet 101 of the cage vehicle 100 to be transported.

[0231] Several embodiments of the present invention have been described, but these embodiments are presented as examples and are not intended to limit the scope of the invention. These embodiments can be implemented in various other ways, and various omissions, substitutions, and changes can be made without departing from the scope of the invention. These embodiments and their variations are included in the scope and spirit of the invention, and are also included in the invention described in the claims and their equivalents.

[0232] For example, in the above-mentioned embodiments, a cage truck is used as an example of a transport object, but the transport object of the unmanned guided vehicle is not limited to a cage truck. For example, a cargo rack composed of columnar support legs can also be a transport object. In this case, the support legs on the entry side do not change their postures with each other, so the entry target reference point M and the docking target position G calculated based on the positions of these entry side support legs are ideal entry target reference point M and docking target position G.

[0233] Furthermore, the direction (long side, short side) of the automated guided vehicle approaching the object to be transported may be appropriately set according to the structure of the object to be transported, the loading state of the cargo, and the like.

Claims

1. An unmanned transport system, wherein an unmanned transport vehicle transports a transport object, wherein the unmanned transport vehicle is capable of transporting the transport object having a cargo plate capable of loading cargo and a plurality of supporting legs supporting at least four corners of the cargo plate, wherein the unmanned transport vehicle comprises: A mobile body capable of autonomously traveling on the ground and having a docking portion for engaging with the transported object; a detection sensor capable of detecting the entry-side support feet when a pair of support feet located on the side where the mobile body docks among the plurality of support feet in the transported object is used as entry-side support feet and a pair of support feet located on the side opposite to the side where the mobile body docks in the traveling direction is used as depth-side support feet; as well as A control device connected to the moving body and the first detection sensor, controlling the moving body, The moving body has a height capable of entering a bottom space surrounded by the lower surface of the cargo plate of the transported object, the plurality of supporting legs and the ground. The control device is used to perform the following steps: The step of detecting the entry side support foot of the transport object by using the first detection sensor; A step of detecting the positions of a pair of the entry-side support legs in the transport object based on the detection result of the first detection sensor, and calculating an entry target reference point that is a target entry position for the transport object and a docking target position that is a target docking position for the transport object; The step of causing the moving body to move in stages from the entry target reference point to the docking target position; as well as The step of docking the automated guided vehicle with the transport object.

2. The unmanned transport system according to claim 1, wherein: The movable body includes the second detection sensor capable of detecting the entry-side support leg and the depth-side support leg of the transported object. The second detection sensor is provided on one side in a width direction intersecting with the traveling direction of the moving body.

3. The unmanned transport system according to claim 1 or 2, wherein: The detection surfaces of the detection sensors are each provided at a height higher than the ground surface and lower than the lower surface of the pallet of the transport object.

4. The unmanned transport system according to claim 1 or 2, wherein: The mobile body includes a third detection sensor capable of detecting the cargo pallet. The detection surface of the third detection sensor is provided at a height higher than the lower surface of the pallet and lower than the upper surface of the pallet.

5. The unmanned transport system according to claim 1 or 2, wherein: As the detection sensor, a side area sensor is used which measures the distance in a spatial plane by laser scanning.

6. The unmanned transport system according to claim 1 or 2, wherein: The mobile object is an omnidirectional mobile object using a Mecanum wheel.

7. The unmanned transport system according to claim 1, wherein: When calculating the docking target position, A pair of point groups closest to the mobile body from among the plurality of object detection location group data detected by the first detection sensor is regarded as the pair of entry side support legs, the midpoint of the first straight line connecting the representative positions of the pair of entry side support legs is calculated as the entry target reference point, and the docking target position is determined in the bottom space on the second straight line orthogonal to the first straight line at the entry target reference point.

8. The unmanned transport system according to claim 1 or 7, comprising: A step of determining whether a passing point needs to be moved between the unmanned guided vehicle and the entry target reference point based on a positional relationship between the entry target reference point and the current position of the unmanned guided vehicle calculated based on a primary detection result of the first detection sensor; as well as The step of causing the vehicle to move in stages from the movement passing point to the docking target position via the entry target reference point.

9. The unmanned transport system according to claim 1 or 7, comprising: The step of calculating a first target entry reference point and a first docking target position according to a detection result of the detection sensor described in step 1; The step of detecting the entry-side supporting legs and the depth-side supporting legs of the transport object on one side in the width direction intersecting the traveling direction of the automated guided vehicle using a second detection sensor; The step of determining the position of the deep side support leg according to the detection result of the second detection sensor, and calculating the first entry target reference point and the second docking target position; as well as and a step of correcting the posture of the moving body based on the second docking target position.

10. The unmanned transport system according to claim 1 or 7, comprising: The step of calculating a first target entry reference point and a first docking target position according to a detection result of the detection sensor described in step 1; The step of detecting the supporting legs on the depth side of the transport object by using the first detection sensor; A step of calculating a second docking target position according to the secondary detection result of the detection sensor in step 1; as well as and a step of correcting the posture of the moving body based on the second docking target position.

11. The unmanned transport system according to claim 1 or 7, comprising: The step of calculating a first target entry reference point and a first docking target position according to a detection result of the detection sensor described in step 1; The step of detecting the pallet of the transported object by using a third detection sensor; The step of calculating a second docking target position according to the secondary detection result of the third detection sensor; as well as and a step of correcting the posture of the moving body based on the second docking target position.

12. A transport program product for an object to be transported by an unmanned guided vehicle according to any one of claims 1 to 6, The porting program product causes the computer system to perform the following processing: The first detection sensor detects the support leg on the entry side of the transport object. The positions of a pair of entry-side support legs in the transport object are detected based on the detection result of the first detection sensor, an entry target reference point that is a target entry position for the transport object and a docking target position that is a target docking position for the transport object are calculated, and the moving body is moved in stages from the entry target reference point to the docking target position. The unmanned guided vehicle is docked with the transport object.

13. A control device for controlling an unmanned guided vehicle, the unmanned guided vehicle being capable of transporting an object having a cargo plate capable of carrying cargo and a plurality of supporting legs for supporting at least four corners of the cargo plate, the unmanned guided vehicle comprising: A mobile body capable of autonomously traveling on the ground and having a docking portion for engaging with the transported object; and The detection sensor can detect the entry-side supporting feet when a pair of supporting feet located on the side where the mobile body docks among the plurality of supporting feet in the transported object is used as entry-side supporting feet and a pair of supporting feet located on the side opposite to the docking side in the traveling direction of the mobile body is used as depth-side supporting feet. The moving body has a height capable of entering a bottom space surrounded by the lower surface of the pallet of the transported object, the plurality of supporting legs, and the ground. The control device enables execution of: Using the first detection sensor to detect the support foot on the entry side of the transport object; Detecting the positions of a pair of entry-side support legs in the transport object based on the detection result of the first detection sensor, and calculating an entry target reference point that is a target entry position for the transport object and a docking target position that is a target docking position for the transport object; causing the moving body to move in stages from the entry target reference point to the docking target position; as well as The unmanned guided vehicle is docked with the transport object.

14. A method for controlling movement of an unmanned guided vehicle, the unmanned guided vehicle being capable of transporting a transport object having a cargo plate capable of carrying cargo and a plurality of supporting legs supporting at least four corners of the cargo plate, the unmanned guided vehicle comprising: A mobile body capable of autonomously traveling on the ground and having a docking portion for engaging with the transported object; a detection sensor capable of detecting the entry-side support feet when a pair of support feet located on the side where the mobile body docks among the plurality of support feet in the transported object is used as entry-side support feet and a pair of support feet located on the side opposite to the side where the mobile body docks in the traveling direction is used as depth-side support feet; as well as a control device connected to the moving body and the first detection sensor, The moving body has a height capable of entering a bottom space surrounded by the lower surface of the pallet of the transported object, the plurality of supporting legs, and the ground. The mobile control method of the unmanned guided vehicle comprises: The step of detecting the entry side support foot of the transport object by using the first detection sensor; A step of detecting the positions of a pair of the entry-side support legs in the transport object based on the detection result of the first detection sensor, and calculating an entry target reference point that is a target entry position for the transport object and a docking target position that is a target docking position for the transport object; The step of causing the moving body to move in stages from the entry target reference point to the docking target position; and The step of docking the automated guided vehicle with the transport object.

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