Driving control system, driving control method, and program

Abstract

The travel control system controls travel of a transport vehicle that travels while towing an object to be transported that is rotatably connected to the transport vehicle. The travel control system includes an angle detection unit that detects a relative angle of the object to be transported with respect to a forward / backward direction of the transport vehicle, starts travel of the transport vehicle in a direction along the forward / backward direction from a state in which the relative angle is an initial angle, travels the transport vehicle at a first speed until the relative angle becomes a specific angle larger than the initial angle, and accelerates the transport vehicle from the first speed to a second speed larger than the first speed when the relative angle becomes equal to or larger than the specific angle.

Description

[Technical field]

[0001] The present disclosure relates to a driving control system, a driving control method, and a program. [Background technology]

[0002] The robot travel controller described in Patent Document 1 calculates the direction and speed at which the robot should move to avoid obstacles, and repeatedly executes the process of actually moving the robot according to the calculation results until it is determined that there is no longer a possibility of collision. As a result, the robot moves along a trajectory that deviates from the original path. During the process of the evasive action, the forward direction of the robot is controlled to maintain the direction of the original path (path vector).

[0003] This control allows the robot to avoid obstacles without changing its forward direction, and since the direction of the laser range finder does not change frequently, the load of obstacle recognition processing can be reduced, allowing the robot to quickly respond to changes in the external environment. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2009-288931 A Summary of the Invention [Problem to be solved by the invention]

[0005] However, the robot described in Patent Document 1 can only avoid obstacles without changing its forward direction, and depending on the situation, the robot may be subjected to sudden strain when performing evasive maneuvers.

[0006] Therefore, the present disclosure has been made in consideration of the above-mentioned problems, and its purpose is to provide a driving control system, a driving control method, and a program that can suppress sudden load on a transport vehicle when the transport vehicle changes direction and travels. [Means for solving the problem]

[0007] According to the present disclosure, there is provided a travel control system for a transport vehicle that travels while towing an object to be transported that is rotatably connected to the transport vehicle, the travel control system including an angle detection unit that detects the relative angle of the object to be transported with respect to the fore-and-aft direction of the transport vehicle, the travel control system starting the travel of the transport vehicle in a direction along the fore-and-aft direction from a state where the relative angle is an initial angle, running the transport vehicle at a first speed until the relative angle becomes a specific angle greater than the initial angle, and accelerating the transport vehicle from the first speed to a second speed greater than the first speed when the relative angle becomes equal to or greater than the specific angle.

[0008] In addition, according to the present disclosure, there is provided a travel control method for a transport vehicle that travels while towing an object to be transported that is rotatably connected to the transport vehicle, the travel control method including the steps of starting travel of the transport vehicle in a direction along the fore-and-aft direction of the transport vehicle from a state in which the relative angle of the object to be transported with respect to the fore-and-aft direction of the transport vehicle is an initial angle, traveling the transport vehicle at a first speed until the relative angle becomes a specific angle greater than the initial angle, and accelerating the transport vehicle from the first speed to a second speed greater than the first speed when the relative angle becomes equal to or greater than the specific angle.

[0009] Further, according to the present disclosure, there is provided a program for causing a computer to execute a travel control method for a transport vehicle that travels while towing an object to be transported that is rotatably connected to the transport vehicle, the travel control method including the steps of starting travel of the transport vehicle in a direction along the fore-and-aft direction of the transport vehicle from a state in which the relative angle of the object to be transported with respect to the fore-and-aft direction of the transport vehicle is an initial angle, traveling the transport vehicle at a first speed until the relative angle becomes a specific angle greater than the initial angle, and accelerating the transport vehicle from the first speed to a second speed greater than the first speed when the relative angle becomes equal to or greater than the specific angle. Effect of the Invention

[0010] According to the present disclosure, it is possible to provide a driving control system, a driving control method, and a program that can prevent a sudden load from being applied to a transport vehicle when the transport vehicle changes its direction of travel and travels. [Brief description of the drawings]

[0011] [Figure 1] FIG. 2 is a plan view illustrating an example of a transport vehicle and a dolly according to an embodiment of the present disclosure. [Diagram 2] 5(a) to 5(c) are plan views showing the flow of the first stage of an example of a cruise control method according to the present embodiment. [Diagram 3] 5(a) to 5(c) are plan views showing the latter stage of the flow of an example of a cruise control method according to the present embodiment. [Figure 4] 5(a) to 5(c) are plan views showing the flow of the first stage of another example of the cruise control method according to the present embodiment. [Diagram 5] 13(a) and 13(b) are plan views showing the middle flow of another example of the cruise control method according to the present embodiment. [Figure 6] 6A and 6B are plan views showing the latter stage of the flow of another example of the cruise control method according to the present embodiment. [Figure 7] FIG. 2 is a perspective view showing an example of a hardware configuration of the transport vehicle according to the present embodiment. [Figure 8]FIG. 2 is a bottom view showing an example of a hardware configuration of the transport vehicle according to the embodiment. [Figure 9] FIG. 2 is a perspective view showing an example of a hardware configuration when a transport vehicle and a dolly according to the present embodiment are coupled together. [Figure 10] FIG. 2 is a plan view showing a configuration example of a motion area according to the present embodiment. [Figure 11] 10 is a bottom view showing the positional relationship between the guide line and the transport vehicle when the two-dimensional code constituting the guide line is detected by the line detection unit according to the embodiment of the present invention. FIG. [Figure 12] 11 is a bottom view showing the positional relationship between the guide line and the transport vehicle when the magnetic tape that constitutes the guide line is detected by the line detection unit according to the embodiment. FIG. [Figure 13] FIG. 1 is a diagram showing an example of an overall configuration diagram of a conveying system according to an embodiment of the present invention; [Figure 14] FIG. 2 is a configuration diagram of an overall control device according to the present embodiment. [Figure 15] FIG. 2 is a diagram showing a functional configuration of a transport vehicle according to the present embodiment. [Figure 16] 4 is a flowchart showing an example of a driving control method according to the present embodiment. [Figure 17] 10 is a flowchart showing an example of a cruise control method according to a modified example of the present embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0012] Hereinafter, preferred embodiments of the present disclosure will be described in detail with reference to the accompanying drawings. In this specification and the drawings, components having substantially the same functional configurations are denoted by the same reference numerals, and redundant description will be omitted.

[0013] A travel control system according to an embodiment of the present disclosure is used to control an automated guided vehicle (hereinafter, also simply referred to as a "guide vehicle") used to transport transported items such as various manufactured parts and luggage in, for example, a manufacturing factory or a logistics warehouse. As an example, the travel control system is realized by a transport system 1000 (FIG. 13) described later. Note that this system is not limited to automated guided vehicles, and can also be applied to other manned and unmanned moving bodies.

[0014] As an example, the transport vehicle has an autonomous driving mode and a guided driving mode. The guided driving mode is a driving mode in which the transport vehicle moves along real or virtual guidelines. The autonomous driving mode is a driving mode in which the transport vehicle can move in an area where no guidelines are arranged by estimating its own position.

[0015] In addition, the transport vehicle travels while towing an object to be transported in the autonomous travel mode and the guided travel mode. The object to be transported is rotatably connected to the transport vehicle. The object to be transported typically has at least one wheel. In this case, the object to be transported may be, for example, a cart, a conveyor, or a robot (for example, a robot having a robot arm).

[0016] First, the transport vehicle 10 and the dolly 2000 will be described with reference to Fig. 1. Fig. 1 is a plan view showing an example of the transport vehicle 10 and the dolly 2000 according to an embodiment of the present disclosure. As shown in Fig. 1, the transport robot 20 includes the transport vehicle 10 and a coupling device 21. The transport robot 20 transports the dolly 2000 by towing it.

[0017] The transport vehicle 10 includes a control unit 260, a recording unit 220, and an angle detection unit 237. The control unit 260 includes a processor such as a CPU (Central Processing Unit) and a GPU (Graphics Processing Unit). The control unit 260 is an example of a computer. The recording unit 220 stores data and computer programs. The recording unit 220 includes a main storage device such as a semiconductor memory, and an auxiliary storage device such as a semiconductor memory and a hard disk drive. The recording unit 220 may include a removable medium such as an optical disk. The recording unit 220 may include, for example, a non-transitory computer-readable storage medium.

[0018] The coupling device 21 couples the transport vehicle 10 and the dolly 2000 so that the dolly 2000 can turn (swing) relative to the transport vehicle 10. The dolly 2000 corresponds to an example of an "object to be transported" in this disclosure.

[0019] As an example, the connecting device 21 includes a connecting body 22, an axis member 23, and a coupling mechanism 24. One longitudinal end of the connecting body 22 is connected to the transport vehicle 10 by the axis member 23. The axis member 23 supports the connecting body 22 so that it can rotate (swing) around a rotation axis AX. The rotation axis AX extends, for example, along the vertical direction. In the example of FIG. 1, the axis member 23 is disposed on a center line CL1 of a width direction D10 of the transport vehicle 10 in a plan view. The width direction D10 of the transport vehicle 10 indicates a direction that is approximately perpendicular to a front-rear direction D20 of the transport vehicle 10.

[0020] A coupling mechanism 24 is attached to the other end of the connecting body 22 in the longitudinal direction. The coupling mechanism 24 is coupled to the bogie 2000 at a coupling point P3 of the bogie 2000. In this case, the coupling mechanism 24 is coupled to the bogie 2000 so that the connecting body 22 cannot rotate (cannot swing) relative to the bogie 2000. As an example, the coupling mechanism 24 is coupled to the bogie 2000 by gripping a predetermined portion of the bogie 2000 at the coupling point P3. In the example of FIG. 1, the coupling point P3 is disposed on a center line CL2 of the width direction D11 of the bogie 2000 in a plan view. The width direction D11 of the bogie 2000 indicates a direction that is approximately perpendicular to the front-rear direction D21 of the bogie 2000.

[0021] The coupling mechanism 24 is coupled to the cart 2000 at the coupling point P3 in a non-rotatable state, but may be rotatable. When the coupling mechanism 24 is coupled to the cart 2000 in a rotatable state, one end of the connector 22 in the longitudinal direction may be coupled to the transport vehicle 10 in a non-rotatable state.

[0022] As a result of the above, the dolly 2000 is coupled to the transporting vehicle 10 by the coupling device 21 so as to be rotatable about the rotation axis AX. In the example of Fig. 1, the dolly 2000 is coupled to the transporting vehicle 10 by the coupling device 21 at the rear thereof.

[0023] Continuing to refer to Figure 1, the first specific location P1 and rotation center P4 of the transport vehicle 10, and the second specific location P2 of the bogie 2000 will be described. The first specific location P1 indicates the position of the transport vehicle 10. In other words, the position of the transport vehicle 10 is indicated by the position of the first specific location P1. The position of the transport vehicle 10 indicated by the first specific location P1 may be referred to as the "own position" or "own vehicle position".

[0024] Here, the carrier 10 further includes a line detector 16. The line detector 16 detects a guide line. The line detector 16 will be described in detail later.

[0025] The first specific location P1 is, for example, the center of the line detection unit 16. The rotation center P4 is the center of rotation when the transport vehicle 10 rotates on its axis. Rotation means that the transport vehicle 10 rotates around the rotation center P4 while barely moving forward, backward, left, or right. In the example of FIG. 1, the first specific location P1 and the rotation center P4 are located on the center line CL1. The first specific location P1 and the rotation center P4 may be at different positions or may be coincident.

[0026] The second specific point P2 of the dolly 2000 indicates the position of the dolly 2000. That is, the position of the dolly 2000 is indicated by the position of the second specific point P2. In the example of FIG. 1, the second specific point P2 is disposed on the center line CL2 of the dolly 2000. In addition, the posture of the dolly 2000 is indicated by the relative angle α of the center line CL2 of the dolly 2000 with respect to the center line CL1 of the carrier 10. That is, the posture of the dolly 2000 is indicated by the relative angle α of the dolly 2000 with respect to the front-rear direction D20 of the carrier 10. The relative angle α is defined based on the front of the carrier 10 in the front-rear direction D20. As an example, the relative angle α is expressed by zero degrees to 180 degrees clockwise of the rotation axis AX with respect to the front of the carrier 10 in a plan view, and zero degrees to 180 degrees counterclockwise of the rotation axis AX with respect to the front of the carrier 10 in a plan view. Note that a positive or negative sign may be assigned to the clockwise and counterclockwise directions. In this case, for example, in the travel control of Fig. 2 to Fig. 6, Fig. 16 and Fig. 17, the relative angle α indicates the absolute value of the relative angle α.

[0027] Also, a guide line 111 is placed on the floor surface. In the example of Fig. 1, the guide line 111 is an actual guide line. Note that the guide line 111 may be a virtual guide line. For example, the guide line 111 extends in a straight line.

[0028] The transport vehicle 10 can move along a real or virtual guideline 111 while towing the dolly 2000. The real guideline 111 is a sign that is installed on a floor, wall, or ceiling surface, or on a signboard rising from these surfaces, and is used to guide the transport vehicle 10. The real guideline 111 may be a continuous line or a sign arranged in a discontinuous line. The guideline 111 may be made of, for example, a magnetic tape. Alternatively, the guideline 111 may be, for example, a plurality of two-dimensional codes arranged in a continuous or discontinuous manner. The virtual guideline 111 may be a virtual two-dimensional or three-dimensional guideline set on two-dimensional or three-dimensional map data corresponding to the real space. In either case, the guideline 111 is set and arranged so that the transport vehicle 10 can be guided to a predetermined position (destination, waypoint) by referring to the guideline 111 when the transport vehicle 10 operates.

[0029] The angle detection unit 237 detects a relative angle α of the dolly 2000 with respect to the forward / rearward direction D20 of the transport vehicle 10. In the example of FIG. 1, the angle detection unit 237 is disposed at a connecting portion between the transport vehicle 10 and the connecting body 22. For example, the angle detection unit 237 includes a rotary encoder provided on the shaft member 23, and measures the relative angle α as a displacement angle from a predetermined state. Alternatively, for example, the angle detection unit 237 includes an angle sensor such as a rotary potentiometer, and detects the relative angle α. Alternatively, for example, the angle detection unit 237 includes a distance measurement sensor, and measures the distance from the transport vehicle 10 to specific points on the left and right of the dolly 2000 to estimate the relative angle α with respect to the transport vehicle 10. Alternatively, the angle detection unit 237 may measure the relative angle α by, for example, a resolver.

[0030] The angle detection unit 237 outputs information indicating the relative angle α to the control unit 260, for example, at regular time intervals, when a specific condition is satisfied, or in response to a request from the control unit 260. The specific condition is satisfied, for example, when the transport vehicle 10 travels a specified distance (every time it travels a specified distance), when the travel direction of the transport vehicle 10 is changed by a specified angle, or when the transport vehicle 10 moves from a stationary state (every time it moves from a stationary state).

[0031] 1 also shows a state in which the transport vehicle 10 enters the guideline 111 at an angle β. The angle β indicates the angle of the front-rear direction D20 (center line CL1) of the transport vehicle 10 with respect to the guideline 111. The angle β is, for example, approximately 90 degrees, an acute angle, or an obtuse angle. For example, in the case of an image recognition method in which the line detection unit 16 uses a camera to read the guideline 111 using a two-dimensional code or a barcode, the control unit 260 can generate position information based on information on the detected code in addition to a detection signal of the guideline 111, and further analyze image information of the code to generate the angle β, which is relative angle information between the guideline 111 and the transport vehicle 10.

[0032] In the following description of FIGS. 2 to 6, the shaft member 23 of the transporting vehicle 10 is disposed at the rotation center P4, and the second specific point P2 of the carriage 2000 is set at the center of gravity of the carriage 2000, as an example.

[0033] Next, an example of a travel control method for the transport vehicle 10 will be described with reference to Fig. 2 and Fig. 3. For example, a travel control method in an autonomous travel mode is shown. Fig. 2 and Fig. 3 are plan views showing an example of the flow of the travel control method. As shown in Fig. 2 and Fig. 3, the travel control method for the transport vehicle 10 includes steps S1 to S6.

[0034] First, as shown in Fig. 2(a), in step S1, the control unit 260 causes the transport vehicle 10 to travel in a direction D1. In the example of Fig. 2(a), the relative angle α (Fig. 1) of the dolly 2000 with respect to the transport vehicle 10 is approximately 180 degrees.

[0035] Next, as shown in FIG. 2(b), in step S2, the control unit 260 stops the transportation vehicle 10.

[0036] Next, as shown in FIG. 2(c), in step S3, the control unit 260 rotates the transport vehicle 10 on its axis so that the relative angle α becomes the initial angle θa from the state in which the transport vehicle 10 is stopped. As a result, the transport vehicle 10 faces the target direction D2. That is, the control unit 260 rotates the transport vehicle 10 on its axis so that the transport vehicle 10 faces the target direction D2 from the state in which the transport vehicle 10 is stopped. The initial angle θa is the angle at which the transport vehicle 10 starts traveling after being stopped. Note that the direction D1 is the traveling direction of the transport vehicle 10 before traveling in the target direction D2. Therefore, before traveling in the target direction D2, the center line CL2 of the carriage 2000 is approximately parallel to the direction D1. In addition, in this example, the traveling direction of the transport vehicle 10 is changed by approximately 90 degrees from the direction D1 (FIG. 2(a)), so that the target direction D2 is approximately perpendicular to the direction D1.

[0037] The initial angle θa is greater than zero degrees. The initial angle θa is not particularly limited, but is, for example, an angle between approximately 80 degrees and approximately 100 degrees. In the example of FIG. 2(c), the initial angle θa is approximately 90 degrees.

[0038] 1, the rotation center P4 and the shaft member 23 are spaced apart, but as shown in FIG. 2(c), it is preferable that the rotation center P4 and the shaft member 23 are approximately aligned. This is because, even when the transport vehicle 10 rotates, the driven motion of the carriage 2000 is suppressed, so that the transport vehicle 10 can rotate smoothly.

[0039] Next, as shown in FIG. 3(a), in step S4, the control unit 260 starts the travel of the transport vehicle 10 toward the target direction D2 from the state in which the transport vehicle 10 is stopped (FIG. 2(c)). In this case, the target direction D2 coincides with the direction along the front-rear direction D20 of the transport vehicle 10. In other words, the control unit 260 starts the travel of the transport vehicle 10 in the direction along the front-rear direction D20 of the transport vehicle 10 from the state in which the transport vehicle 10 is stopped (from the state in which the relative angle α is the initial angle θa).

[0040] Next, as shown in FIG. 3(b), in step S5, the control unit 260 accelerates the transport vehicle 10 from a stopped state to a first speed V1. Then, the control unit 260 maintains the speed of the transport vehicle 10 at the first speed V1. As the transport vehicle 10 travels, the relative angle α gradually increases. Then, the control unit 260 causes the transport vehicle 10 to travel at the first speed V1 until the relative angle α becomes a specific angle θb that is larger than the initial angle θa.

[0041] The control unit 260 acquires information indicating the speed of the transportation vehicle 10 from a speed sensor (for example, the travel distance detection unit 233 in FIG. 15).

[0042] Next, as shown in Fig. 3(c), in step S6, when the relative angle α becomes equal to or larger than the specific angle θb, the control unit 260 accelerates the transport vehicle 10 from the first speed V1 to the second speed V2. The second speed V2 is greater than the first speed V1. Then, the control unit 260 maintains the speed of the transport vehicle at the second speed V2.

[0043] As described above with reference to FIG. 2 and FIG. 3, according to this embodiment, the transport vehicle 10 travels at the first speed V1, which is smaller than the second speed V2, until the relative angle α becomes the specific angle θb (step S5). Therefore, the relative angle α gradually increases by traveling at the small first speed V1. Then, when the relative angle α becomes equal to or larger than the specific angle θb, the transport vehicle 10 accelerates to the second speed V2 (step S6). In this way, the target speed of the transport vehicle 10 is increased stepwise according to the magnitude of the relative angle α of the carriage 2000 with respect to the forward / rearward direction D20 of the transport vehicle 10. That is, in the initial stage of traveling when the relative angle α is relatively small, the transport vehicle 10 travels at the small first speed V1, and when the relative angle α becomes relatively large, the transport vehicle 10 is accelerated to the large second speed V2.

[0044] Therefore, when the transport vehicle 10 changes its traveling direction and starts traveling, it is possible to suppress a sudden load on the transport vehicle 10 compared to a case where the transport vehicle 10 is accelerated to the second speed V2 immediately after the transport vehicle 10 rotates. As a result, the transport vehicle 10 is not required to generate a sudden torque when changing its traveling direction and starts traveling, and can start traveling smoothly. In addition, the durability of the transport vehicle 10 and the coupling device 21 can be improved.

[0045] In particular, the closer the initial angle θa is to 90 degrees, the greater the load on the transport vehicle 10 may be when the transport vehicle 10 is accelerated in the direction along the forward-rear direction D20. Therefore, when the transport vehicle 10 changes its traveling direction by approximately 90 degrees, the load on the transport vehicle 10 may be the greatest when the transport vehicle 10 is accelerated.

[0046] That is, in step S3, in order to change the traveling direction by approximately 90 degrees, the control unit 260 may rotate the transport vehicle 10 from the stopped state so that the relative angle α becomes approximately 90 degrees (=initial angle θa). In this case, if the speed of the transport vehicle 10 is immediately accelerated to the second speed V2, the load on the transport vehicle 10 may be particularly large. Therefore, in this embodiment, by gradually increasing the target speed of the transport vehicle 10 according to the magnitude of the relative angle α (steps S5 and S6), it is possible to more effectively suppress a sudden load on the transport vehicle 10 even when the traveling direction is changed by approximately 90 degrees. As a result, the transport vehicle 10 is not required to generate a sudden torque and can start traveling smoothly.

[0047] In this embodiment, the control unit 260 rotates the transport vehicle 10 on its axis while the transport vehicle 10 is stopped (step S3), thereby directing the transport vehicle 10 toward the target direction D2. Therefore, compared to changing the traveling direction of the transport vehicle 10 without stopping the transport vehicle 10, it is easier to control the transport vehicle 10 to face the target direction D2, and the time required to direct the transport vehicle 10 toward the target direction D2 can be shortened.

[0048] Furthermore, in this embodiment, the specific angle θb when changing the target speed of the transport vehicle 10 to the second speed V2 is preferably an angle equal to or greater than approximately 110 degrees and equal to or less than approximately 120 degrees. According to this preferred example, it has been experimentally and / or empirically proven that the speed of the transport vehicle 10 can be accelerated from the first speed V1 to the second speed V2 more smoothly.

[0049] Next, another example of the travel control method of the transported vehicle 10 will be described with reference to Figs. 4 to 6. For example, a travel control method in a guided travel mode is shown. Figs. 4 to 6 are plan views showing another example of the flow of the travel control method. As shown in Figs. 4 to 6, the travel control method of the transported vehicle 10 includes steps S11 to S17.

[0050] First, as shown in FIG. 4(a), in step S11, the control unit 260 causes the transportation vehicle 10 to travel in a direction D1 indicating the position of the guide line 111 (not shown in FIG. 4(a)).

[0051] 4(b), in step S12, the control unit 260 stops the transport vehicle 10 so that the first specific point P1 is located on the guide line 111. In other words, the control unit 260 stops the transport vehicle 10 at the position where the line detection unit 16 detects the guide line 111.

[0052] Next, as shown in FIG. 4(c), in step S13, the control unit 260 moves the transport vehicle 10 forward (straight) along the front-rear direction D20 so that the rotation center P4 of the transport vehicle 10 is positioned on the guide line 111. Specifically, the control unit 260 moves the transport vehicle 10 forward along the front-rear direction D20 by a distance L4 and stops the transport vehicle 10. The distance L4 is the distance between the first specific location P1 (line detection unit 16) and the rotation center P4. Information indicating the distance L4 is stored in advance in the recording unit 220 (FIG. 1).

[0053] 5(a), in step S14, the control unit 260 rotates the carrier 10 so that the relative angle α becomes the initial angle θa from the state in which the rotation center P4 is located on the guide line 111. As a result, the carrier 10 faces the target direction D2.

[0054] In this case, the target direction D2 of the transport vehicle 10 coincides with the forward / backward direction D20 of the transport vehicle 10 and the extending direction of the guide line 111. Therefore, the initial angle θa indicates the angle of the forward / backward direction D21 of the carriage 2000 relative to the guide line 111. Therefore, in step S14, the control unit 260 essentially rotates the transport vehicle 10 on its axis so that the first specific point P1 (FIG. 4(c)), which is located outside the guide line 111, is positioned on the guide line 111. In other words, the control unit 260 rotates the transport vehicle 10 on its axis until the line detection unit 16 detects the guide line 111.

[0055] The magnitude of the initial angle θa is the same as the result of subtracting the angle β (FIG. 1) at which the guided vehicle 10 enters the guide line 111 from 180 degrees.

[0056] Here, the initial angle θa is the same as the initial angle θa described with reference to Fig. 2(c). For example, when the transport vehicle 10 enters the guide line 111 at an angle β (Fig. 1) of approximately 90 degrees, the initial angle θa in Fig. 5(a) is approximately 90 degrees.

[0057] Next, as shown in Fig. 5(b), in step S15, the control unit 260 starts the travel of the transport vehicle 10 from a stopped state (Fig. 5(a)) toward the target direction D2 along the guide line 111. That is, the control unit 260 starts the travel of the transport vehicle 10 from a stopped state to a forward / rearward direction D20 of the transport vehicle 10 along the guide line 111.

[0058] Next, as shown in Fig. 6(a), in step S16, the control unit 260 accelerates the transport vehicle 10 from a stopped state until the transport vehicle 10 accelerates to a first speed V1. Then, the control unit 260 maintains the speed of the transport vehicle 10 at the first speed V1. Otherwise, step S16 is similar to step S5 in Fig. 3(b).

[0059] Next, as shown in Fig. 6(b), in step S17, when the relative angle α becomes equal to or greater than the specific angle θb, the control unit 260 accelerates the transport vehicle 10 from the first speed V1 to the second speed V2. Then, the control unit 260 maintains the speed of the transport vehicle at the second speed V2. Otherwise, step S17 is similar to step S6 in Fig. 3(c). Also, it is preferable that the specific angle θb is an angle equal to or greater than approximately 110 degrees and equal to or less than approximately 120 degrees.

[0060] According to the travel control method of this embodiment described above with reference to Figs. 4 to 6, the target speed of the transport vehicle 10 is increased stepwise depending on the magnitude of the relative angle α of the carriage 2000 with respect to the forward / rearward direction D20 of the transport vehicle 10 (steps S16, S17). Therefore, in the guided travel mode, as in the case of the autonomous travel mode described with reference to Figs. 2 and 3, it is possible to prevent the transport vehicle 10 from being subjected to a sudden load when the transport vehicle 10 changes its traveling direction and travels. As a result, the transport vehicle 10 is not required to generate a sudden torque when changing its traveling direction and travels, and can start traveling smoothly. In addition, the durability of the transport vehicle 10 and the coupling device 21 can be improved.

[0061] <Construction of the transport vehicle> FIG. 7 is a perspective view showing an example of the hardware configuration of the transport vehicle 10 according to this embodiment. The transport vehicle 10 in this embodiment is an unmanned transport vehicle, but can also be applied to various vehicles on which people can ride. An arrow 15 in FIG. 7 indicates the traveling direction (forward) of the transport vehicle 10. The traveling direction is basically the forward direction of the transport vehicle 10, but can also be the rear direction depending on the situation. As shown in FIG. 7, the transport vehicle 10 is equipped with an object position detection unit 12 that detects objects around the transport vehicle 10, drive wheels 13, and non-drive wheels 14. In addition, the transport vehicle 10 is provided with a shaft member 23 of a coupling device 21 (FIG. 1) for coupling a dolly 2000.

[0062] The object position detection section 12 corresponds to an example of an "object detection section" in the present disclosure.

[0063] The object position detection unit 12 detects an object in a non-contact manner. Specifically, the object position detection unit 12 can also detect the relative distance and angle from the transport vehicle 10 to an object (including the dolly 2000, a person, etc.). As the object position detection unit 12, a laser distance sensor (such as LiDAR (Light detection and ranging)) that measures the distance and direction to an object by irradiating a laser light and measuring the time it takes for the laser light to hit the object and bounce back, a millimeter wave radar that detects the distance to an object based on a millimeter wave transmission signal and a received signal that is reflected by the object and returns, or a camera-type distance sensor that measures the distance to an object by photographing the object with a camera and analyzing the photographed image, etc., can be applied. In this embodiment, an example has been shown in which the object position detection unit 12 is disposed on the front of the top surface of the transport vehicle 10 in the traveling direction, but instead of this, it may be disposed on the front side in the traveling direction. Also, it may be disposed not only on the front but also on the rear side or both left and right sides in the traveling direction.

[0064] The object position detection unit 12 can detect the position and attitude (relative position and angle with respect to the transport vehicle 10) of the dolly 2000 coupled to the transport vehicle 10. The object position detection unit 12 may be configured to detect objects in 360 degrees around the transport vehicle 10, but is configured to be able to detect objects at least in the traveling direction 15 of the transport vehicle 10. The traveling direction 15 may be either forward or backward of the transport vehicle 10.

[0065] FIG. 8 is a bottom view showing an example of the hardware configuration of the transport vehicle 10 according to this embodiment. FIG. 8 shows the bottom of the transport vehicle 10. Drive wheels 13 are provided on both the left and right sides of the bottom of the transport vehicle 10 with respect to the traveling direction 15 of the transport vehicle 10, and non-driven wheels 14 are provided in front and behind each of the drive wheels 13. The drive wheels 13 are wheels that are connected to the rotating shaft of a motor and driven, and the right drive wheel 13 and the left drive wheel 13 are individually controlled. The control unit 260 can control the speed of the transport vehicle 10 by controlling the rotation speed of the drive wheels 13. In addition, the control unit 260 can control the rotation speed and rotation direction of each drive wheel 13 individually, thereby making it possible to make the transport vehicle 10 run on a curve, rotate the transport vehicle 10 on the spot to change direction, stop it, or move backward.

[0066] For example, the control unit 260 can rotate the transport vehicle 10 around the rotation center P4 by controlling the two drive wheels 13 to have the same rotation speed but different rotation directions (for example, step S3 in FIG. 2(c) and step S14 in FIG. 5(a)). The midpoint between the pair of drive wheels 13 is the rotation center P4. For example, the control unit 260 can rotate the transport vehicle 10 by controlling the two drive wheels 13 to have different rotation speeds but the same rotation direction.

[0067] The non-driven wheels 14 are configured as wheels that are not driven, and rotate passively as the transport vehicle 10 moves with the driven wheels 13. The non-driven wheels 14 have, for example, a fork that fixes the wheel and the axle, and the fork is configured as a rotating caster that is rotatably connected to the bottom member of the transport vehicle 10. Therefore, the wheel rotation direction of the non-driven wheels 14 changes passively according to the traveling direction and rotational movement of the transport vehicle 10. In other words, the non-driven wheels 14 are free wheels that can rotate 360 ​​degrees while in contact with the floor surface.

[0068] FIG. 8 illustrates an example of a hardware configuration of a transport vehicle 10 having two driven wheels 13 and four non-driven wheels 14 at the four corners, but the present disclosure is not limited to this hardware configuration, and it is also possible to adopt a configuration with a total of four wheels, two driven wheels 13 and two non-driven wheels 14, and it is also possible to adopt a configuration in which the front wheels are steerable in the four-wheel configuration.

[0069] A line detector 16 for detecting the guideline 111 is provided on the bottom surface of the transport vehicle 10. The line detector 16 is preferably provided ahead of the drive wheels 13 in the traveling direction of the transport vehicle 10. This makes it easier for the transport vehicle 10 to travel along the guideline 111 when traveling along a curved line, and also allows the transport vehicle 10 and the towing dolly 2000 to receive information from the guideline 111 as soon as possible when traveling, thereby enabling them to quickly execute processing such as stopping. The line detector 16 uses a sensor according to the type of induction method. When the induction method is an electromagnetic induction method, a pickup coil is used as the sensor of the line detector 16, when the induction method is an electromagnetic induction method, a magnetic sensor is used as the sensor of the line detector 16, and when the image recognition method is used, a camera is used as the sensor of the line detector 16. The guideline 111 is not limited to a floor surface, but may be provided on a side wall surface, a ceiling surface, or the like of a building, and a sensor (including a camera) of the transport vehicle 10 can be installed at a position where the guideline 111 can be recognized (the bottom surface, side surface, top surface, etc. of the transport vehicle 10). The guide line 111 may be a virtually established track on two-dimensional or three-dimensional map data. The control unit 260 of the transport vehicle 10 may control the travel of the transport vehicle 10 along the virtual guide line 111 based on map information and track information (travel route information) previously stored in the recording unit 220 and current self-position information estimated based on information from a camera, a sensor, etc.

[0070] Information on the position of the shaft member 23 is stored in advance in the recording unit 220. The position of the line detection unit 16 may be set in three-dimensional coordinates. As shown in FIG. 8, the center point (middle point) between the left and right drive wheels 13 is the rotation center P4. In this example, the rotation center P4 coincides with the center of the transport vehicle 10, but may be shifted. Information on the relative positional relationship between the rotation center P4, the center of the transport vehicle 10, and the shaft member 23, such as the distance L2 from the rotation center P4 to the shaft member 23 and the distance L3 from the center of the transport vehicle 10 to the shaft member 23, is also stored in advance in the recording unit 220. In addition, the distance L4 between the line detection unit 16 (first specific location P1) and the rotation center P4, and the distance L1 between the line detection unit 16 (first specific location P1) and the shaft member 23 are also stored in advance in the recording unit 220.

[0071] 9 shows an example of a hardware configuration when the transport vehicle 10 according to this embodiment is coupled to the dolly 2000. The dolly 2000 is coupled to the transport vehicle 10 by a coupling device 21 so as to be rotatable (swingable) about an axis member 23 as a fulcrum.

[0072] The dolly 2000 has at least one wheel 2001. In the example of Fig. 9, the dolly 2000 has four wheels 2001. As an example, all the wheels 2001 are free wheels that can freely rotate 360 ​​degrees while in contact with the floor surface. Note that the multiple wheels 2001 may include fixed wheels.

[0073] FIG. 10 is a diagram showing a configuration example of the operation area 130 according to the present embodiment. As shown in FIG. 10, a guideline 131 is laid in the operation area 130, and when the guideline 131 is detected at a preset travel mode switching position 132 by the guideline 131, the travel control mode is switched from the autonomous travel mode to the guided travel mode. Conversely, when the guideline 131 is detected at the preset travel mode switching position 132 by the guideline 131, the travel control mode is switched from the guided travel mode to the autonomous travel mode. In order to guide the guideline 131 to a position close to the shelf or belt conveyor where the baggage is stored, or the work position of the worker, the track formed by the guideline 131 is laid at a position close to the shelf or work position via multiple branch points.

[0074] The guided vehicle 10 traveling in an autonomous travel area where no guideline 131 is laid in the autonomous travel mode enters the travel mode switching position 132 and changes the travel mode to a guided travel mode that follows the guideline 131 on the condition that the guided travel mode switching position 132 is detected. On the other hand, when the guided vehicle 10 traveling in the guided travel mode on the guideline 131 enters the travel mode switching position 132, the travel control mode is switched from the guided travel mode to the autonomous travel mode, and the guided vehicle 10 leaves the guideline 131 and starts autonomous travel.

[0075] As the guideline 131 shown in Fig. 10, various commonly used guideline induction methods, as described later, can be applied. Specifically, for example, an electromagnetic induction method in which a pickup coil on the transport vehicle detects a magnetic field generated by passing a weak AC current through a metal wire installed as the guideline 131, a magnetic induction method in which a magnetic sensor on the transport vehicle reads a magnetic tape laid on the floor as the guideline 131, or an image recognition method in which a camera on the transport vehicle 10 captures an image of a code (such as a barcode or a two-dimensional code) laid on the floor as a guide line and processes the image can be applied.

[0076] 11 shows the positional relationship between the guideline 111 and the transport vehicle 10 when the line detection unit 16 detects the two-dimensional code 1001 that constitutes the guideline 111. The guideline 111 is formed by printing a plurality of two-dimensional codes 1001, each having code information printed on a two-dimensional plane as shown in the two-dimensional code 1001, lined up in the direction of the guideline 111. When the line detection unit 16 detects the two-dimensional code 1001, it acquires position information of the two-dimensional code 1001 based on the code information acquired from the two-dimensional code 1001.

[0077] FIG. 12 shows the positional relationship between the guideline 111 and the transport vehicle 10 when the magnetic tape constituting the guideline 111 is detected by the line detection unit 16. The line detection unit 16 shown in FIG. 12 is configured to have a plurality of magnetic sensors 17 for detecting the magnetic tape arranged horizontally toward the traveling direction of the transport vehicle 10. Each of the plurality of magnetic sensors 17 provided in the line detection unit 16 outputs a detection signal indicating whether or not the magnetic tape has been detected. In the case shown in FIG. 12, three magnetic sensors 17A located in the center of the line detection unit 16 detect the magnetic tape, and two magnetic sensors 17B on each side of the line detection unit 16 do not detect the magnetic tape. This makes it possible to detect where the guideline is located (rightward, leftward, center, etc.) within the range of the line detection unit 16 (the entire area including the plurality of magnetic sensors).

[0078] <Conveyor system configuration> Next, the configuration of the transport system 1000 of this embodiment will be described. The transport system 1000 corresponds to an example of the "travel control system" of the present disclosure. In other words, the transport system 1000 is a travel control system for a transport vehicle 10 to which a cart 2000 is rotatably (swingably) connected and capable of moving along a real or virtual guide line 111 while towing the cart 2000.

[0079] 13 is a diagram showing an example of the overall configuration of the transport system 1000 according to the present embodiment. The transport system 1000 includes a plurality of transport vehicles 10, a dolly 2000 as a transport object, a control device 3000 capable of displaying the state of the transport vehicles 10 or inputting commands to the transport vehicles 10, a general control device 4000 for managing information required for the operation of the transport vehicles 10, an input / output device 5000 for displaying information of the general control device 4000 and inputting information to the general control device 4000, and a communication network 6000 for communicatively connecting the plurality of transport vehicles 10, the control device 3000, and the general control device 4000. The various devices such as the control device 3000, the general control device 4000, and the input / output device 5000 may be separate devices, or may be formed as an integrated device in part or in whole.

[0080] The transport system 1000 can also be connected to an external system 7000 via a communication network 6000. When the transport system 1000 is introduced into a manufacturing factory to transport parts required for manufacturing from a storage facility to a manufacturing line, the transport system 1000 performs inter-system cooperation with a manufacturing management system as the external system 7000. In this case, by acquiring information on the operational progress of the manufacturing work from the manufacturing management system, the transport volume and transport route of the transport vehicle 10 can be dynamically adjusted according to the progress of the manufacturing work.

[0081] As another example, when the conveyance system 1000 is introduced into a logistics warehouse, and when luggage is brought into the warehouse by truck or the like, the conveyance system 1000 conveys the incoming luggage from an inlet to a storage warehouse, and when luggage is shipped from the warehouse, the conveyance system 1000 performs inter-system cooperation with a logistics management system as an external system 7000. In this case, by acquiring information related to the incoming luggage and the outgoing luggage from the logistics management system, the transportation amount and transportation route of the conveyance vehicle 10 can be changed.

[0082] In a facility where the transport system 1000 is installed, a plurality of transport vehicles 10 are generally in operation, and each transport vehicle 10 is communicably connected to the other transport vehicles 10 and other components via the communication network 6000. For example, the transport vehicle 10 transmits various detection information detected by its own detection unit and other control information to the control device 3000, the general control device 4000, and the other transport vehicles 10. The transport vehicle 10 is also electrically connected to the cart 2000 or communicably connected via short-range communication means, and is configured to be able to receive information on the connection state and identification information of the cart 2000 from the cart 2000.

[0083] The controller 3000 has a function of displaying status information of each transport vehicle 10 and a function of inputting commands to a specified transport vehicle 10. For example, the status information of the transport vehicle 10 displayed on the controller 3000 includes the identification information, position (coordinates, position on a map), speed, direction, travel history, information on the charge level of a battery mounted on the transport vehicle 10 and serving as the power source for the transport vehicle 10, and identification information of the cart 2000 transported by the transport vehicle 10. Examples of commands input to the transport vehicle 10 include command information related to the destination (destination position) of the transport vehicle 10, operation commands for coupling and uncoupling with the cart 2000, commands to start traveling for the transport vehicle 10, commands to stop the transport vehicle 10, and commands to return to a charging station.

[0084] 14 shows a configuration diagram of the overall control device 4000 in this embodiment. The overall control device 4000 has a status information recording unit 4010 that records status information of multiple transport vehicles 10 operated in a facility area, an operation scenario management unit 4020 that manages operation scenarios of the multiple transport vehicles 10, a map management unit 4030 that generates and updates a map of the work area based on detection information of the transport vehicles 10 including detection information of the guide line 111 acquired by the line detection unit 16 of the transport vehicles 10, an abnormality determination unit 4040 that determines abnormalities of the guide line 111 and the transport vehicles 10 based on the detection information of the transport vehicles 10, and a communication unit 4050 that communicates with an external input / output device 5000 and a communication network 6000.

[0085] The status information of the transport vehicle 10 recorded by the status information recording unit 4010 includes, for example, obstacle detection positions detected by the multiple transport vehicles 10 during operation, guideline detection positions, history information of the travel positions of the transport vehicles 10, information on the battery charge amount, identification information of the dolly 2000 connected to the multiple transport vehicles 10, operation modes (guided travel mode or autonomous travel mode) of the multiple transport vehicles 10, various other detection information detected by the detection unit 230 of the transport vehicles 10, map information of the work area, etc. The operation scenario managed by the operation scenario management unit 4020 is information that defines a series of operation contents to be performed by the transport vehicle 10. The operation scenario includes, for example, information on the destination of each of the multiple transport vehicles 10, multiple operation contents to be performed until reaching the destination, the operation sequence of the multiple operations, and switching conditions for the multiple operations.

[0086] The map management unit 4030 generates a map including the position information of obstacles and the guideline 111 in the work area based on the obstacle detection position, the guideline detection position, and the history information of the traveling position of the guideline 110, which are detected by the guided vehicle 10. Furthermore, the map management unit 4030 updates the information of the guideline 111 and the work area registered in the map based on the information of the detection position of the guideline 111 accumulated by one or more guided vehicles 10.

[0087] The abnormality determination unit 4040 determines abnormalities in the guideline 111 and the guided vehicle 10 based on the position information of the guideline 111 registered in the map information and the detection information of the guideline 111 including the detection position information of the guideline 111 detected by the guided vehicle 10.

[0088] The input / output device 5000 displays information recorded in the state information recording unit 4010 of the overall control device 4000, map information (including map update information), and the determination result by the abnormality determination unit 4040, and can add or update a new operation scenario by inputting an operation scenario managed by the operation scenario management unit 4020. Information input to the input / output device 5000 includes, for example, information that the destination of any transport vehicle 10 is a work area of ​​the guided travel area, operation contents for entering the guided travel area and reaching the work area, operation switching conditions, and the like.

[0089] <Functions of the transport vehicle> The functions of the transport vehicle 10 will be described with reference to Fig. 15. Fig. 15 is a diagram showing a functional configuration diagram of the transport vehicle 10 according to this embodiment. The transport vehicle 10 includes a communication unit 210 that communicates with a dolly 2000 outside the transport vehicle 10 and a communication network 6000, a recording unit 220 (including a memory unit), a detection unit 230 including various sensors described below, a wheel drive unit 280 that drives the drive wheels 13, an input unit 240, a display unit 250, and a control unit 260. The control unit 260 controls the operation of the transport vehicle 10 by controlling the wheel drive unit 280 of the transport vehicle 10.

[0090] The recording unit 220 has a function of recording information received by the communication unit 210 from the outside, detection information detected by the detection unit 230, and information generated and output by the control unit 260. The recording unit 220 stores position information of the first specific location P1 of the transport vehicle 10, etc. The recording unit 220 can store information such as the destination position, movement route, and movement history of the transport vehicle 10. The recording unit 220 can store speed information according to the distance to the destination position, calculation formula (program) information for calculating the speed information, etc.

[0091] The detection unit 230 includes an object position detection unit 12, a line detection unit 16, a travel distance detection unit 233, a collision detection unit 234, a posture detection unit 235, a charge amount detection unit 236, and an angle detection unit 237. As described above, the object position detection unit 12 includes a laser distance sensor (such as LiDAR (Light detection and ranging)) that measures the distance and direction to an object by irradiating a laser beam and measuring the time it takes for the laser beam to bounce back after hitting the object, a millimeter wave radar that detects the distance to an object based on a millimeter wave transmission signal and a received signal that is reflected by the object and returns, or a camera-type distance sensor that measures the distance to an object by photographing the object with a camera and analyzing the photographed image. The control unit 260 can estimate information on the current position and current speed of the transport vehicle 10 based on the information from the detection unit 230. The detection unit 230 may include a position sensor including a GNSS or the like that detects the current position of the transport vehicle 10, and a speed sensor that detects the speed of the transport vehicle 10.

[0092] As described above, the line detection unit 16 uses a sensor according to the type of induction method. When the induction method is an electromagnetic induction method, a pickup coil is used as the sensor of the line detection unit 16. When the magnetic induction method is used, a magnetic sensor is used, and when the image recognition method is used, a camera is used. When the line detection unit 16 is located directly above the guideline 111, the line detection unit 16 detects the guideline 111 and outputs a detection signal. In addition, in the case of an image recognition method in which the camera reads the guideline 111 using a two-dimensional code or a barcode, the control unit 260 generates position information based on information on the detected code in addition to the detection signal of the guideline 111, and further analyzes image information of the code to generate relative angle information (angle β in FIG. 1) between the guideline 111 and the carrier 10.

[0093] The travel distance detection unit 233 detects the number of rotations of the non-driven wheels 14 or the driven wheels 13, and can measure the travel distance and travel speed of the transport vehicle 10 based on the detection information of the number of rotations and the information of the diameter (or circumference) of the non-driven wheels 14 or the driven wheels 13. In this case, the travel distance detection unit 233 functions as a speed sensor. As an alternative, it is also possible to apply a means for detecting the travel speed of the transport vehicle 10 using a millimeter wave sensor that irradiates millimeter waves in any horizontal direction (which may be a wall or floor) and detects reflected waves, and integrating the travel speed to estimate the travel distance. In addition, any method for measuring the travel distance or acquiring the travel speed other than the above-mentioned methods is also applicable.

[0094] The collision detection unit 234 has a function of detecting that the transport vehicle 10 collides with an object or a person. Specifically, it is possible to detect acceleration using a gyro sensor or the like, and determine that a collision has occurred when a sudden change in acceleration is detected. As an alternative, it is also possible to apply a means of providing a physical switch together with a bumper at the front of the transport vehicle 10 in the traveling direction, and determining that a collision has occurred when the physical switch is pressed. In addition, a collision detection method other than the above can be applied. When the collision detection unit 234 detects a collision, it stops the transport vehicle 10, records at least one of the collision occurrence information and the collision occurrence position information in the recording unit 220, and notifies the information to the general control device 4000 and the control device 3000. The attitude detection unit 235 detects the direction (attitude) of the transport vehicle 10 (own vehicle) based on a magnetic compass, information on the rotation speed of the left and right drive wheels, or steering information of the wheels.

[0095] The charge amount detection unit 236 detects the charge amount of the battery which is the power source of the transport vehicle 10. When the charge amount detected by the charge amount detection unit 236 becomes equal to or less than a predetermined value, it determines that charging is necessary, records the detection information of the decrease in charge amount in the recording unit 220, and notifies the information to the general control device 4000 and the control device 3000. Furthermore, when it is detected that the charge amount is equal to or less than a predetermined value, in addition to the above processing, it may be configured to automatically move to a charging spot and charge. The predetermined value for the charge amount detection unit 236 to determine that charging is necessary may be a value set in advance based on at least one of the distance to the destination set for the transport vehicle 10 and the weight of the cart 2000 coupled to the transport vehicle 10. The angle detection unit 237 detects the attitude of the cart 2000 with respect to the transport vehicle 10 (for example, the relative angle α in FIG. 1).

[0096] The input unit 240 is composed of a physical switch or a touch panel mounted on the transport vehicle 10, and allows a user to directly input operation commands and the like to the transport vehicle 10. The display unit 250 is composed of, for example, a liquid crystal panel mounted on the transport vehicle 10, and can display status information of the transport vehicle 10 (various types of detection information by the detection unit 230, the type of driving mode, the currently executed operation scenario, and the like).

[0097] The control unit 260 includes an operation determination unit 261, a mode switching unit 262, a connection control unit 263, a display control unit 264, a position estimation unit 265, and a traveling control unit 266. Specifically, the control unit 260 executes a computer program stored in the recording unit 220 to function as the operation determination unit 261, the mode switching unit 262, the connection control unit 263, the display control unit 264, the position estimation unit 265, and the traveling control unit 266.

[0098] The operation determination unit 261 determines the operation of the guided vehicle 10 based on the operation scenario of the self-guided vehicle acquired from the operation scenario management unit 4020. The mode switching unit 262 switches the travel mode of the guided vehicle 10 between a guided travel mode and an autonomous travel mode based on conditions predetermined by the operation scenario or the like, or a command input by the input unit 240. The connection control unit 263 controls the operation of the coupling device 21 (FIG. 1) based on conditions predetermined by the operation scenario or the like, or a command input by the input unit 240, to control the connection / disconnection with the cart 2000. The display control unit 264 controls the input IF of the input unit 240 and the display unit 250 described above.

[0099] The position estimation unit 265 can estimate the position and attitude of the vehicle at a predetermined time including the current position and current attitude in the entire travel area based on the travel distance detected by the travel distance detection unit 233, the information on the direction of the vehicle detected by the attitude detection unit 235, and the map information of the entire area recorded in the recording unit 220. Alternatively, the position estimation unit 265 can estimate the position and attitude of the vehicle in the entire travel area based on the information on the distance and direction from the vehicle to an object measured by the object position detection unit 12 and the map information of the entire area recorded in the recording unit 220. If the map information includes the guideline 111, the relative position and attitude with respect to the guideline 111 can also be estimated. Alternatively, if the carrier vehicle 10 is traveling on the guideline 111 configured by a two-dimensional code, the position and attitude of the vehicle in the entire travel area can be estimated based on the identification information of the two-dimensional code and the map information. The position estimation unit 265 can also acquire position information by a GNSS or the like provided in the carrier vehicle 10.

[0100] The position estimation unit 265 can estimate the position where the object exists based on the estimated self-position information (own vehicle position information) and distance information from the own vehicle to the object detected by the object position detection unit 12. It is also possible to estimate the installation position and extension angle of the guide line 111 based on the self-position information (own vehicle position information) and attitude information when the line detection unit 16 detects the guide line 111.

[0101] The travel control unit 266 controls the travel of the transport vehicle 10 based on at least one of the determination information by the operation determination unit 261 and the mode switching unit 262. The travel control unit 266 can control the forward movement, backward movement, stop, rotational movement, rotation on its own axis, linear speed, rotational movement speed, and rotational speed of the transport vehicle 10. Specifically, the travel control unit 266 individually controls the right wheel drive unit 281 and the left wheel drive unit 282 of the wheel drive unit 280. The right wheel drive unit 281 and the left wheel drive unit 282 are composed of, for example, a motor, and by individually controlling the rotational speed and rotational direction of each drive wheel 13, it becomes possible to make the transport vehicle 10 travel on a curve with an arbitrary trajectory radius or to rotate the transport vehicle 10 on the spot to change its direction.

[0102] The driving control unit 266 controls the wheel driving unit 280 to control the drive wheels 13, for example, and executes the driving control method described with reference to FIGS.

[0103] For example, when moving along the guideline 111, the control unit 260 can execute a travel control process to control the travel speed of the transport vehicle 10 based on the differential distance between the current position of the transport vehicle 10 in the extension direction of the guideline 111 and the destination position. The travel control unit 266 may execute a distance estimation process to calculate the differential distance between the current position of the transport vehicle 10 in the extension direction of the guideline 111 and the destination position based on the current position information of the transport vehicle 10 and the destination position information.

[0104] The distance estimation process can estimate the distance difference between the current position of the transport vehicle 10 in the extension direction of the guideline 111 and the destination position, for example, by calculating the difference between the position coordinates as the current position information of the transport vehicle 10 and the position coordinates of the destination position as the destination position information.

[0105] The control unit 260 may execute a travel control process based on the distance to the destination position when the transport vehicle 10 advances toward the destination position, and may execute a travel control process to control the speed in the reverse direction based on the distance in the same way as in the forward direction when the transport vehicle 10 passes the destination position. In this case, even if the transport vehicle 10 passes the destination position, it can reach the destination position while moving backward with high accuracy and efficiency in the same way as when moving forward.

[0106] The control unit 260 may perform an angle estimation process to estimate the angle of the transport vehicle 10 with respect to the extension direction of the guide line 111 based on information from a sensor provided on the transport vehicle 10, a relative position estimation process to estimate the relative position between the guide line 111 and the first specific point P1 of the transport vehicle 10 in a direction perpendicular to the extension direction of the guide line 111 based on information from a sensor provided on the transport vehicle 10, and control the orientation of the transport vehicle 10 based on the angle and relative position of the transport vehicle 10. For example, in the case of an image recognition method in which the guide line 111 using a two-dimensional code or a barcode is read by a camera, position information may be generated based on information on the detected code in addition to the detection signal of the guide line 111, and image information of the code may be further analyzed to generate relative angle information (for example, angle β in FIG. 1) between the guide line 111 and the transport vehicle 10. For example, the control unit 260 may control the travel of the transport vehicle 10 so that the angle (direction) of the transport vehicle 10 finally coincides with the extension direction of the guideline 111 (or the difference in angle is equal to or less than a predetermined value (e.g., 1°, 3°, 5°, etc.)) and so that the deviation between the guideline 111 and the transport vehicle 10 in a direction perpendicular to the extension direction of the guideline 111 is equal to or less than a predetermined value. For example, when it is determined that the deviation between the guideline 111 and the transport vehicle 10 in a direction perpendicular to the guideline 111 exceeds a predetermined value, the control unit 260 can drive and control the transport vehicle 10 to move forward or backward by changing the direction (angle) of the transport vehicle 10 toward the guideline 111 so that the transport vehicle 10 approaches the guideline 111. Furthermore, when the deviation between the guideline 111 and the transport vehicle 10 in a direction perpendicular to the guideline 111 is equal to or less than a predetermined value, the control unit 260 can drive and control the transport vehicle 10 to be in the same direction as the guideline 111.

[0107] In the distance estimation process, the control unit 260 may calculate the distance from the current position to the destination position based on the difference between the current position acquired from the position estimation unit 265 and the destination position acquired from the recording unit 220. Alternatively, the control unit 260 may perform image recognition of a two-dimensional code provided on a floor or wall, and acquire information on the distance (the distance from the current position to the destination position) associated with the two-dimensional code.

[0108] The control unit 260 may execute a travel control process based on speed information acquired by a speed sensor of the transport vehicle 10. The type of the speed sensor is not particularly limited, and any sensor such as a sensor that detects the number of rotations or the rotation speed of the drive wheels 13, or a camera can be used as the speed sensor. The control unit 260 detects the speed of the transport vehicle 10 at predetermined intervals, judges whether the speed matches the target speed, and can control the travel while repeatedly adjusting it. That is, the control unit 260 judges whether the difference between the actual speed and the target speed is equal to or less than a predetermined value (predetermined threshold value, etc.), and if it is equal to or less than the predetermined value, maintains control, and if it exceeds the predetermined value, can perform deceleration or acceleration control so as to approach the target speed. By repeating such a speed adjustment process, it is possible to suppress (reduce) deviation from the target speed.

[0109] The control unit 260 may acquire information such as the current position, the distance to the destination position, and / or the target speed at that point, which are associated with the two-dimensional code, by scanning the two-dimensional code with a sensor (camera). For example, if information on the target speed is associated with the two-dimensional code, the carrier 10 can acquire the information on the target speed from the two-dimensional code and execute the above-mentioned speed control.

[0110] Next, an example of a travel control method according to this embodiment will be described with reference to Fig. 16. The travel control method is a method for controlling travel of the transport vehicle 10 which travels by towing a dolly 2000 rotatably connected to the transport vehicle 10. Fig. 16 is a flowchart showing an example of the travel control method. As shown in Fig. 16, the travel control method of the transport vehicle 10 includes steps S101 to S112.

[0111] First, in step S101, the control unit 260 starts the transportation vehicle 10 traveling in the direction D1.

[0112] Next, in step S102, the angle detection unit 237 starts detecting the relative angle α of the dolly 2000 with respect to the forward / rearward direction D20 of the transporting vehicle 10. Then, the control unit 260 starts acquiring, from the angle detection unit 237, information indicating the relative angle α.

[0113] Next, in step S103, the control unit 260 determines whether or not a specific event has occurred. The specific event is a trigger for changing the traveling direction of the transport vehicle 10. The specific event is not particularly limited, but for example, a request to change the traveling direction of the transport vehicle 10 in the operation scenario. Alternatively, for example, the specific event is the object position detection unit 12 detecting an object on the travel path of the transport vehicle 10. The object includes, for example, an obstacle, a wall, and a person.

[0114] If the determination in step S103 is negative (NO), the control proceeds to step S112.

[0115] On the other hand, if the determination in step S103 is affirmative (YES), the control proceeds to step S104.

[0116] Next, in step S104, the control unit 260 stops the transportation vehicle 10.

[0117] Next, in step S105, the control unit 260 rotates the carrier 10 on its axis so that the relative angle α becomes the initial angle θa.

[0118] Next, in step S106, the control unit 260 starts traveling of the transportation vehicle 10 in the direction along the front-rear direction D20 from a state in which the relative angle α is the initial angle θa.

[0119] Next, in step S107, the control unit 260 causes the carrier 10 to travel at a first speed V1.

[0120] Next, in step S108, the control unit 260 determines whether the relative angle α has become equal to or greater than a specific angle θb.

[0121] If the determination in step S108 is negative (NO), the control returns to step S107.

[0122] On the other hand, if the determination in step S108 is affirmative (YES), the control proceeds to step S109.

[0123] Next, in step S109, the control unit 260 accelerates the guided vehicle 10 from the first speed V1 to a second speed V2 that is higher than the first speed V1.

[0124] Next, in step S110, the control unit 260 determines whether the speed of the guided vehicle 10 has reached the second speed V2.

[0125] If the determination in step S110 is negative (NO), the control returns to step S109.

[0126] On the other hand, if the determination in step S110 is affirmative (YES), the control proceeds to step S111.

[0127] Next, in step S111, the control unit 260 causes the carrier 10 to travel at a second speed V2.

[0128] Next, in step S112, the control unit 260 controls the traveling of the guided vehicle 10 according to the operation scenario stored in the recording unit 220. Then, when all the operations defined in the operation scenario are completed, the traveling control method ends.

[0129] 16, according to the travel control method of this embodiment, the target speed of the transporting vehicle 10 is increased stepwise depending on the magnitude of the relative angle α of the carriage 2000 with respect to the forward / rearward direction D20 of the transporting vehicle 10 (steps S107 to S111). Therefore, when the transporting vehicle 10 changes its traveling direction and travels, it is possible to prevent a sudden load from being applied to the transporting vehicle 10, so that the transporting vehicle 10 is not required to generate a sudden torque and can start traveling smoothly.

[0130] In this embodiment, the control unit 260 stops the transport vehicle 10 (step S104) on the condition that the object position detection unit 12 detects an object (step S103: YES), and rotates the transport vehicle 10 from the stopped state so that the relative angle α becomes the initial angle θa (step S105). Then, the control unit 260 starts the transport vehicle 10 traveling in a direction along the front-rear direction D20 from a state in which the relative angle α is the initial angle θa (step S106). Then, the control unit 260 further increases the target speed of the transport vehicle 10 in stages according to the magnitude of the relative angle α (steps S107 to S111). Therefore, when an object such as an obstacle is present on the traveling path, it is possible to suppress a sudden load from being applied to the transport vehicle 10 when the transport vehicle 10 changes its traveling direction and travels.

[0131] Here, when the carriage 2000 is not coupled to the transport vehicle 10, the control unit 260 may not increase the target speed of the transport vehicle 10 stepwise when changing the traveling direction of the transport vehicle 10. That is, in this case, the control unit 260 may start the travel of the transport vehicle 10 after the transport vehicle 10 rotates, and accelerate the transport vehicle 10 from a stopped state to the third speed V3 without depending on the magnitude of the relative angle α. This is because, when the carriage 2000 is not coupled to the transport vehicle 10, no load caused by the carriage 2000 is applied to the transport vehicle 10. The third speed V3 is greater than the first speed V1. The third speed V3 may be the same as the second speed V2, for example.

[0132] 16, the control unit 260 sets the target speed in two stages, such as the first speed V1 and the second speed V2. However, for example, the control unit 260 may set the target speed in three or more stages according to the relative angle α.

[0133] (Modification) A modified example of the above embodiment will be described with reference to Figures 15 and 17. In the modified example, a travel control parameter (e.g., second speed V2) is changed when changing the traveling direction of the transport vehicle 10 according to the load (e.g., the weight of the dolly 2000 and the load) on the transport vehicle 10. Below, differences between the modified example and the above embodiment will be mainly described.

[0134] The control unit 260 shown in Fig. 15 sets the direction change control information in accordance with the towing load information. Therefore, the control unit 260 can change the direction change control information in accordance with the towing load information.

[0135] The towing load information is information that indicates the load applied to the transporting vehicle 10 when the transporting vehicle 10 tows the dolly 2000 .

[0136] Specifically, the traction load information is information indicating the weight of the dolly 2000, information indicating the weight of the load on the dolly 2000, or information indicating the weight of the dolly 2000 and the load.

[0137] The information indicating the weight of the dolly 2000 may be, for example, the weight of the dolly 2000 itself, or a physical quantity correlated with the weight of the dolly 2000. In this case, the physical quantity is, for example, the load applied to the transport vehicle 10 when the transport vehicle 10 tows the dolly 2000.

[0138] The information indicating the weight of the load on the dolly 2000 may be the weight itself of the load loaded on the dolly 2000, or a physical quantity correlated with the weight of the load on the dolly 2000. In this case, the physical quantity is, for example, a load caused by the load among the loads applied to the transport vehicle 10 when the transport vehicle 10 tows the dolly 2000 on which the load is loaded.

[0139] The information indicating the weight of the dolly 2000 and the load may be the sum of the weight of the dolly 2000 and the weight of the load, or may be a physical quantity correlated to the sum of the weight of the dolly 2000 and the weight of the load. In this case, the physical quantity is, for example, the load applied to the transport vehicle 10 when the transport vehicle 10 tows the dolly 2000 with the load.

[0140] The unit of the above physical quantity is not particularly limited, and may be, for example, a unit related to mass (kg, etc.) or the unit of an output value output by a load sensor.

[0141] The direction change control information indicates travel control parameters when changing the traveling direction of the guided vehicle 10.

[0142] Specifically, the driving control parameters include information on at least one of the first speed V1, the second speed V2, the acceleration A1 from when the transport vehicle 10 is stopped until it reaches the first speed V1, the acceleration A2 from when the transport vehicle 10 reaches the second speed V2 from the first speed V1, and a specific angle θb.

[0143] For example, the control unit 260 sets the travel control parameters (excluding the specific angle θb) to smaller values ​​as the load indicated by the traction load information increases. And / or, the control unit 260 sets the travel control parameters (specific angle θb) to larger values ​​as the load indicated by the traction load information increases. As a result, it is possible to suppress a sudden load applied to the transport vehicle 10 when the transport vehicle 10 changes its traveling direction and travels.

[0144] Next, an example of a travel control method according to a modified example will be described with reference to Fig. 17. Fig. 17 is a flowchart showing an example of a travel control method according to a modified example. As shown in Fig. 17, the travel control method for the guided vehicle 10 includes steps S201 to S214.

[0145] First, steps S201 to S203 are executed. Steps S201 to S203 are similar to steps S101 to S103 in FIG.

[0146] If the determination in step S203 is negative (NO), the control proceeds to step S214.

[0147] On the other hand, if the determination in step S203 is affirmative (YES), the control proceeds to step S204.

[0148] Next, in step S204, the control unit 260 acquires towing load information.

[0149] For example, the weight of the dolly 2000 is stored in advance in the recording unit 220. In this case, the control unit 260 acquires information on the weight of the dolly 2000 from the recording unit 220. Also, the weight of the load may be stored in advance in the recording unit 220. In this case, the control unit 260 acquires information on the weight of the load on the dolly 2000 from the recording unit 220.

[0150] For example, a load cell is installed in the coupling device 21 (e.g., the coupling body 22). The load cell detects the load acting on the transport vehicle 10 due to the dolly 2000 and the load. Alternatively, for example, a plurality of load cells are installed on the platform of the dolly 2000. The plurality of load cells detect the load due to the load placed on the platform.

[0151] Information indicating the load detected by the load cell is transmitted to the transport vehicle 10 via the overall control device 4000 and the communication network 6000, or directly, by a communication device mounted on the cart 2000. The control unit 260 receives the information indicating the load.

[0152] For example, the control unit 260 estimates the load acting on the transport vehicle 10 due to the cart 2000 and the load based on the power consumption (=current x voltage) of the motor of the wheel drive unit 280. Specifically, the power consumption of the motor increases as the load acting on the transport vehicle 10 increases. For example, the power consumption of the motor is approximately proportional to the load acting on the transport vehicle 10. Therefore, the control unit 260 can estimate the load acting on the transport vehicle 10 based on the power consumption of the motor of the wheel drive unit 280.

[0153] Next, in step S205, the control unit 260 sets the direction change control information according to the traction load information. Therefore, according to the modified example, the control unit 260 can set the travel control parameters (excluding the specific angle θb) to smaller values, for example, as the load indicated by the traction load information increases. For example, the control unit 260 can set the travel control parameters (specific angle θb) to larger values, for example, as the load indicated by the traction load information increases. As a result, it is possible to more effectively suppress a sudden load applied to the transport vehicle 10 when the transport vehicle 10 changes its traveling direction and travels. Therefore, the transport vehicle 10 is not required to generate a sudden torque, and can start traveling smoothly.

[0154] Next, steps S206 to S214 are executed. Steps S206 to S214 are similar to steps S104 to S112 in Fig. 16. Then, when all the operations defined in the operation scenario are completed, the driving control method ends.

[0155] Here, the direction change control information may include at least one of the following: the first speed V1, the second speed V2, the acceleration A1 from when the transport vehicle 10 is stopped until it reaches the first speed V1, the acceleration A2 from when the transport vehicle 10 reaches the second speed V2 from the first speed V1, the specific angle θb, and additional control information.

[0156] The additional control information includes information on a target speed Vn after the speed of the transport vehicle 10 reaches the second speed V2, and information on a target angle θn of the relative angle α, which is a condition for starting acceleration when accelerating the transport vehicle 10 from the second speed V2 to the target speed Vn. The additional control information may include information on an acceleration An when accelerating the transport vehicle 10 toward the target speed Vn.

[0157] In this case, the control unit 260 accelerates the transport vehicle 10 toward the target speed Vn when the relative angle α becomes equal to or greater than the target angle θn after the transport vehicle 10 reaches the second speed V2. In this case, the control unit 260 may change at least one piece of information among the first speed V1, the second speed V2, the acceleration A1, the acceleration A2, and the specific angle θb, depending on the content of the additional control information.

[0158] Note that the number of each of the target speed Vn, the target angle θn, and the acceleration An is not limited to one, and a plurality of values ​​may be set.

[0159] Although the preferred embodiment of the present disclosure has been described in detail above with reference to the attached drawings, the technical scope of the present disclosure is not limited to such examples. It is clear that a person having ordinary knowledge in the technical field of the present disclosure can conceive of various modified or amended examples within the scope of the technical ideas described in the claims, and it is understood that these also naturally belong to the technical scope of the present disclosure.

[0160] The devices described in this specification may be realized as a single device, or may be realized by a plurality of devices (e.g., cloud servers) partially or entirely connected via a network. For example, the control unit 260 and the recording unit 220 of the transport vehicle may be realized by different servers connected to each other via a network, or may be realized by the overall control device 4000 of the transport system 1000. In addition, in the transport system 1000 described in this specification, an example has been described in which the controller 3000, the overall control device 4000, and the input / output device 5000 are configured as separate hardware connected via a network, but some or all of the functions of the controller 3000, the overall control device 4000, and the input / output device 5000 may be implemented in the transport vehicle 10.

[0161] The series of processes performed by the device described in this specification may be realized using any of software, hardware, and a combination of software and hardware. A computer program for realizing each function of the control unit 260 according to this embodiment may be created and implemented in a PC or the like. A computer-readable recording medium in which such a computer program is stored may also be provided. The recording medium may be, for example, a magnetic disk, an optical disk, a magneto-optical disk, a flash memory, or the like. The above computer program may also be distributed, for example, via a network, without using a recording medium.

[0162] 2 to 6, 16, and 17, the control unit 260 executes each step included in the driving control method by executing a computer program stored in the recording unit 220. In other words, the computer program causes the control unit 260 to execute each step included in the driving control method. The control unit 260 corresponds to an example of a "computer" in the present disclosure. In further other words, the computer program product realizes each step included in the driving control method when the computer program is executed by the control unit 260.

[0163] In addition, the effects described in this specification are merely descriptive or exemplary and are not limiting. In other words, the technology according to the present disclosure may achieve other effects that are apparent to a person skilled in the art from the description of this specification, in addition to or in place of the above effects.

[0164] Note that the following configurations also fall within the technical scope of the present disclosure.

[0165] (Item 1) A travel control system for a transport vehicle that travels while towing an object to be transported that is rotatably connected to the transport vehicle, comprising: an angle detection unit that detects a relative angle of the object to be transported with respect to a front-rear direction of the transport vehicle; The transport vehicle starts traveling in a direction along the front-rear direction from a state in which the relative angle is an initial angle; running the carrier at a first speed until the relative angle becomes a specific angle larger than the initial angle; When the relative angle becomes equal to or greater than the specific angle, the travel control system accelerates the carrier from the first speed to a second speed that is greater than the first speed.

[0166] (Item 2) 2. The cruise control system of claim 1, wherein the initial angle is approximately 90 degrees.

[0167] (Item 3) The transport vehicle is rotated so that the relative angle becomes the initial angle from a state in which the transport vehicle is stopped. 3. The travel control system according to claim 1, wherein the transport vehicle starts traveling in a direction along the forward-backward direction from a state in which the relative angle is the initial angle.

[0168] (Item 4) 4. The cruise control system according to any one of items 1 to 3, wherein the specific angle is an angle equal to or greater than approximately 110 degrees and equal to or less than approximately 120 degrees.

[0169] (Item 5) An object detection unit that detects an object in a non-contact manner is further provided, on condition that the object detection unit detects the object, stopping the transport vehicle and rotating the transport vehicle on its axis so that the relative angle becomes the initial angle from the stopped state; 5. The travel control system according to any one of items 1 to 4, wherein the transport vehicle starts traveling in a direction along the forward-rear direction from a state in which the relative angle is the initial angle.

[0170] (Item 6) Setting direction change control information according to towing load information; the towing load information is information indicating a weight of the object to be transported, information indicating a weight of a load on the object to be transported, or information indicating a weight of the object to be transported and the load, the direction change control information includes at least one of the first speed, the second speed, an acceleration of the transporting vehicle from a stopped state until the transporting vehicle reaches the first speed, an acceleration of the transporting vehicle from the first speed until the transporting vehicle reaches the second speed, the specific angle, and additional control information; The driving control system according to any one of items 1 to 5, wherein the additional control information includes information on a target speed after the speed of the transporting vehicle reaches the second speed, and a target angle of the relative angle, which is a condition for starting acceleration when accelerating the transporting vehicle from the second speed to the target speed.

[0171] (Item 7) A method for controlling travel of a transport vehicle that travels while towing an object to be transported that is rotatably connected to the transport vehicle, comprising: starting travel of the transport vehicle in a direction along the forward-backward direction from a state in which a relative angle of the object to be transported with respect to the forward-backward direction of the transport vehicle is an initial angle; running the carrier at a first speed until the relative angle becomes a specific angle greater than the initial angle; When the relative angle becomes equal to or greater than the specific angle, accelerating the guided vehicle from the first speed to a second speed that is greater than the first speed.

[0172] (Item 8) A program for causing a computer to execute a travel control method for a transport vehicle that travels while towing an object to be transported that is rotatably connected to the transport vehicle, comprising: The driving control method includes: starting travel of the transport vehicle in a direction along a forward / backward direction from a state in which a relative angle of the object to be transported with respect to the forward / backward direction of the transport vehicle is an initial angle; running the carrier at a first speed until the relative angle becomes a specific angle greater than the initial angle; When the relative angle becomes equal to or greater than the specific angle, accelerating the transport vehicle from the first speed to a second speed that is greater than the first speed. [Industrial Applicability]

[0173] The present disclosure provides a travel control system, a travel control method, and a program for a transport vehicle, and has industrial applicability. [Explanation of symbols]

[0174] 10 transport vehicle, 12 object position detection unit (object detection unit), 13 drive wheel, 14 non-drive wheel, 16 line detection unit, 17 magnetic sensor, 21 coupling device, 111 guide line, 132 driving mode switching position, 210 communication unit, 220 recording unit, 230 detection unit, 237 angle detection unit, 240 input unit, 250 display unit, 260 control unit, 280 wheel drive unit, 1000 transport system (travel control system), 2000 cart (transport object), 3000 control unit, 4000 overall control device, 5000 input / output device, 6000 communication network, 7000 external system

Claims

1. A travel control system for a transport vehicle that travels while towing an object to be transported that is rotatably connected to the transport vehicle, comprising: an angle detection unit that detects a relative angle of the object to be transported with respect to a front-rear direction of the transport vehicle; The transport vehicle starts traveling in a direction along the front-rear direction from a state in which the relative angle is an initial angle; running the carrier at a first speed until the relative angle becomes a specific angle larger than the initial angle; When the relative angle becomes equal to or greater than the specific angle, the travel control system accelerates the transport vehicle from the first speed to a second speed that is greater than the first speed.

2. The cruise control system of claim 1 , wherein the initial angle is approximately 90 degrees.

3. The transport vehicle is rotated so that the relative angle becomes the initial angle from a state in which the transport vehicle is stopped. The travel control system according to claim 1 or 2, wherein the transport vehicle starts traveling in the forward-rearward direction from a state in which the relative angle is the initial angle.

4. 3. The cruise control system according to claim 1, wherein the specific angle is equal to or greater than approximately 110 degrees and equal to or less than approximately 120 degrees.

5. An object detection unit that detects an object in a non-contact manner is further provided, on condition that the object detection unit detects the object, stopping the transport vehicle and rotating the transport vehicle on its axis so that the relative angle becomes the initial angle from the stopped state; The travel control system according to claim 1 or 2, wherein the transport vehicle starts traveling in the forward-rearward direction from a state in which the relative angle is the initial angle.

6. Setting direction change control information according to towing load information; the towing load information is information indicating a weight of the object to be transported, information indicating a weight of a load on the object to be transported, or information indicating a weight of the object to be transported and the load, the direction change control information includes at least one of the first speed, the second speed, an acceleration of the transporting vehicle from a stopped state until the transporting vehicle reaches the first speed, an acceleration of the transporting vehicle from the first speed until the transporting vehicle reaches the second speed, the specific angle, and additional control information; 3. The driving control system of claim 1, wherein the additional control information includes information on a target speed after the speed of the transport vehicle reaches the second speed, and a target angle of the relative angle that is a condition for starting acceleration when accelerating the transport vehicle from the second speed to the target speed.

7. A method for controlling travel of a transport vehicle that travels while towing an object to be transported that is rotatably connected to the transport vehicle, comprising: starting travel of the transport vehicle in a direction along the forward-backward direction from a state in which a relative angle of the object to be transported with respect to the forward-backward direction of the transport vehicle is an initial angle; running the carrier at a first speed until the relative angle becomes a specific angle greater than the initial angle; When the relative angle becomes equal to or greater than the specific angle, accelerating the guided vehicle from the first speed to a second speed that is greater than the first speed.

8. A program for causing a computer to execute a travel control method for a transport vehicle that travels while towing an object to be transported that is rotatably connected to the transport vehicle, comprising: The driving control method includes: starting travel of the transport vehicle in a direction along a forward / backward direction from a state in which a relative angle of the object to be transported with respect to the forward / backward direction of the transport vehicle is an initial angle; running the carrier at a first speed until the relative angle becomes a specific angle greater than the initial angle; When the relative angle becomes equal to or greater than the specific angle, accelerating the transport vehicle from the first speed to a second speed greater than the first speed.