Transport system and charging management device

Abstract

A transport system according to the present invention includes an unmanned transport vehicle that transports an object using power from a battery. The transport system comprises a charging end determination unit which, when the operation of the unmanned transport vehicle is stopped and the battery is being charged during a prescribed operation time, sets an end threshold value that becomes smaller as the remaining time until the operation time ends becomes smaller and determines the end of charging of the battery on the basis of the remaining battery capacity and the end threshold value.

Description

Transport system and charging management device

[0001] The present specification discloses a transportation system and a charge management device.

[0002] Conventionally, there have been proposals for managing the charging of autonomous mobile bodies such as automated guided vehicles and robots. For example, Patent Literature 1 describes a system for ensuring the amount of charge required for an autonomous mobile body to perform a task by determining the start and end times of the task of the autonomous mobile body and the start and end times of the movement of the autonomous mobile body so that the amount of charge of the autonomous mobile body at the installation location of a charger is equal to or greater than the required amount.

[0003] International Publication No. 2018 / 211650

[0004] In this case, when the start time and end time of the operation (service) of the autonomous mobile body are predetermined, it is conceivable to uniformly determine the start time and end time of charging based on the charge amount. However, in this case, even if the charge amount becomes sufficient to operate until the end time of the operation, the operation cannot be resumed because the set end time has not been reached, and the availability rate may decrease.

[0005] A primary object of the present disclosure is to increase the time that an automated guided vehicle transports an object, thereby improving the utilization rate.

[0006] The present disclosure has adopted the following means to achieve the above-mentioned main object.

[0007] The transport system disclosed herein is a transport system including an automated guided vehicle that transports an object using battery power, and when operation of the automated guided vehicle is stopped during a predetermined operating time to charge the battery, the transport system is provided with a charge end determination unit that sets an end threshold that decreases as the time remaining until the end of the operating time decreases, and determines when charging of the battery should be ended based on the remaining charge of the battery and the end threshold.

[0008] In the transport system disclosed herein, when the battery is being charged, the termination threshold is set to decrease as the remaining time until the end of the operating time decreases, and the termination of battery charging is determined based on the remaining battery charge and the termination threshold. Therefore, even if the remaining battery charge remains the same, charging can be terminated and the automated guided vehicle can resume operation depending on the remaining time. This increases the time that the automated guided vehicle transports objects, thereby improving the operating rate.

[0009] 1 is a schematic configuration diagram of a transport system 1. An external perspective view of an automated guided vehicle 10 and a cart 100. An external perspective view of the automated guided vehicle 10. A side view of the automated guided vehicle 10. A side view of the automated guided vehicle 10. An explanatory diagram showing a state in which the automated guided vehicle 10 has slipped under the cart 100. An explanatory diagram showing a state in which the automated guided vehicle 10 has been coupled to the cart 100. A block diagram of the transport system 1. A flowchart showing an example of a charge management process. A flowchart showing an example of a charge start determination process. A flowchart showing an example of a charge end determination process. An explanatory diagram showing an example of a relationship between a first end threshold E1 and a second end threshold E2. A flowchart showing an example of an operation end process. An explanatory diagram showing an example of a battery consumption rate P associated with operation information. A flowchart showing a modified example of a charge start determination process. A flowchart showing a modified example of a charge start determination process.

[0010] An embodiment of the present disclosure will be described with reference to the drawings. Fig. 1 is a schematic configuration diagram of a conveyance system 1. Fig. 2 is an external perspective view of an automated guided vehicle 10 and a cart 100. Fig. 3 is an external perspective view of the automated guided vehicle 10. Figs. 4 and 5 are side views of the automated guided vehicle 10. Fig. 6 is an explanatory diagram showing a state in which the automated guided vehicle 10 has slipped under the cart 100. Fig. 7 is an explanatory diagram showing a state in which the automated guided vehicle 10 is coupled to the cart 100. Fig. 8 is a block diagram of the conveyance system 1.

[0011] As shown in Fig. 1 , the transport system 1 of this embodiment is used in a logistics center, warehouse, store, or the like having a plurality of shelves R, and includes one or more (two are illustrated in Fig. 1 ) automated guided vehicles 10 and a management device 60 (see Fig. 8 ) that manages the operation of the automated guided vehicles 10. The automated guided vehicles 10 are autonomously traveling transport robots (AMR: Autonomous Mobile Robot) that are coupled to a basket cart 100 and transport the automated guided vehicles 10 to a designated shelf R. The automated guided vehicles 10 are charged in a charging area 80.

[0012] As shown in Fig. 2, the basket cart 100 has a rectangular, mesh-shaped loading platform 101 capable of loading cargo, and a plurality of (for example, four) casters 110 rotatably attached to the underside of the loading platform 101. The loading platform 101 of the basket cart 100 is provided with a marker M, such as an AR marker, a two-dimensional code, or a barcode, for identifying the basket cart 100. By reading the marker M, the automated guided vehicle 10 recognizes the basket cart 100 to be transported (transport target vehicle) and the type of cargo loaded on the loading platform 101. The marker M may be attached to the cargo loaded on the loading platform 101.

[0013] As shown in FIG. 3 , the automated guided vehicle 10 of this embodiment has a low, flat, rectangular parallelepiped appearance. The automated guided vehicle 10 includes a vehicle body 11, a plurality of (e.g., four) wheels 21 rotatably attached to the bottom surface of the vehicle body 11, and a plurality of (e.g., four) drive motors 22 (see FIG. 8 ) that rotate and drive the corresponding wheels 21. In this embodiment, the wheels 21 are configured as Mecanum wheels, each having a plurality of rollers on its outer periphery that can rotate around an axis inclined at 45 degrees relative to the rotation axis of the wheel. The automated guided vehicle 10 can move the vehicle body 11 in all directions and turn (such as by making a pivot turn, a pivot turn, or a gentle turn) by independently controlling the rotation direction and rotation speed of the corresponding wheels 21 using the plurality of drive motors 22. The wheels 21 may also be configured as omniwheels having a plurality of rollers that can rotate around an axis that intersects the rotation axis of the wheel. That is, the plurality of wheels 21 may be any type of wheels as long as they can move the vehicle body 11 in a plurality of directions and turn.

[0014] 4 and 5 , the automated guided vehicle 10 also includes a connecting unit 30 that is provided on the upper surface of the vehicle body 11 and can be connected to the cart 100 when the vehicle body 11 is positioned below the cart 100. The connecting unit 30 includes a flat lift plate 31, connecting pins 32, 33, and 34 that extend upward relative to the lift plate 31, and a lifting device 35 that raises and lowers the lift plate 31. The lift plate 31 covers the upper surface of the vehicle body 11 and has a width that is approximately the same as the width of the vehicle body 11 and a front-to-rear width that is slightly shorter than the front-to-rear width of the vehicle body 11. The connecting pin 32 is provided at the front of the lift plate 31, the connecting pin 33 is provided at the rear of the lift plate 31, and the connecting pin 34 is provided in an intermediate portion between the front and rear of the lift plate 31. 6 and 7 , when the vehicle body 11 is submerged under the cart 100 and the lifting plate 31 is raised by the lifting device 35, at least one of the connecting pins 32, 33, 34 engages with the back side of the loading platform 101 of the cart 100. This connects the automated guided vehicle 10 and the cart 100, and the automated guided vehicle 10 can transport the cart 100.

[0015] As shown in FIGS. 3 to 5 , contact detection sensors 36 (spring sensors) are provided on both the left and right sides of the lift plate 31 to detect when the connecting portion 30 (connecting pins 32, 33, 34) comes into contact with (connects to) the loading platform 101 of the cart truck 100. The contact detection sensors 36 have a plate that is biased upward by a spring, with its upper end at approximately the same height as the connecting pins 32, 33, 34 relative to the lift plate 31. When the connecting pins 32, 33, 34 engage with the loading platform 101 of the cart truck 100, the plate of the contact detection sensor 36 comes into contact with the loading platform 101, and the spring is compressed as it descends relative to the connecting pins 32, 33, 34. The contact detection sensor 36 detects when the connecting portion 30 comes into contact with (connects to) the loading platform 101 of the cart truck 100 by detecting that the plate has descended relatively.

[0016] As shown in FIG. 8 , the automated guided vehicle 10 further includes a control unit 40 that controls the entire system, a memory unit 41 that stores various information, a communication unit 42 that communicates (wirelessly communicates) with a management device 60 and the like, a camera unit 51 as an imaging device, sensors 52 and 53, and a light-emitting unit 54 that illuminates the area ahead of the vehicle body 11. The camera unit 51 is installed on the front of the vehicle body 11 to recognize the area ahead of the vehicle body 11. The sensors 52 and 53 are installed on the front and rear of the vehicle body 11, respectively, to detect surrounding obstructions. The sensors 52 and 53 detect surrounding objects and the distance to the objects. In this embodiment, the sensors 52 and 53 are light detection and ranging (LiDAR) sensors that scan the surroundings with laser light, receive each reflected light, and measure the time it takes for the reflected light to be received, thereby measuring distance data for each scan angle and obtaining surrounding point cloud data. The light emitting unit 54 is installed on the front of the vehicle body 11 and illuminates the area ahead, making it easier for the camera unit 51 to recognize surrounding objects in dark places.

[0017] The automated guided vehicle 10 also includes a battery 37 that supplies power to each of the drive motors 22, the lifting device 35, the control unit 40, the memory unit 41, the communication unit 42, the camera unit 51, the sensors 52 and 53, the light-emitting unit 54, and other components, as well as a battery remaining capacity meter 38 that measures the remaining capacity (remaining battery capacity B) of the battery 37. The battery 37 is a rechargeable secondary battery, such as a lithium-ion battery. The battery remaining capacity meter 38 includes a current sensor attached to the output terminal of the battery 37 and a voltage sensor attached between the output terminals of the battery 37, and calculates the remaining battery capacity B as the ratio of the remaining capacity to the maximum capacity of the battery 37 based on the detected values ​​of each sensor.

[0018] The control unit 40 is configured as a microprocessor centered around a CPU, and in addition to the CPU, includes a ROM for storing processing programs, a RAM for temporarily storing data, a timer, etc. As shown in Fig. 8, the control unit 40 receives inputs such as image signals from the camera unit 51, detection signals from the sensors 52 and 53, detection signals from the contact detection sensor 36, and detection signals from the battery remaining gauge 38. The control unit 40 outputs control signals to the drive motor 22, control signals to the lifting device 35, control signals to the light-emitting unit 54, etc.

[0019] The charging area 80 is formed with one or more sections (two in FIG. 1 ) in which the automated guided vehicle 10 can park. Each section is provided with a charger for charging the battery 37 of the automated guided vehicle 10. In this embodiment, the charger is a contact-type charging stand having a power supply electrode on its upper surface. When the automated guided vehicle 10 moves into a section of the charging area 80 and stands on the charging stand, a power receiving electrode (not shown) provided on the bottom of the automated guided vehicle 10 electrically connects with a power supply electrode of the charging stand, thereby charging the battery 37. Note that the charging area 80 may also be capable of charging the battery 37 in a non-contact manner.

[0020] 8, the management device 60 includes a processing unit 61, a storage unit 62, a communication unit 63 for communicating (wirelessly communicating) with the automated guided vehicle 10, and a timer unit 64 for acquiring the time. Input devices such as a mouse and a keyboard, and a display are also connected to the management device 60. The processing unit 61 is configured as a microprocessor centered around a CPU, and includes, in addition to the CPU, a ROM for storing processing programs, a RAM for temporarily storing data, and the like. The storage unit 62 is a storage device such as an HDD or SSD, and stores various types of information.

[0021] Next, the operation of the transport system 1 of this embodiment configured as described above will be described. In particular, the charge management of the battery 37 while the automated guided vehicle 10 is operating to automatically transport the basket cart 100 will be described. Note that the automated guided vehicle 10 automatically transports the basket cart 100 one by one from a basket cart storage area C within a store to the front of each target shelf R. This automatic transportation is performed during a predetermined operating time from the end of store business until the start of the next business day (for example, 8 hours from the start of operation at 9:00 PM to the end of operation at 5:00 AM the following day).

[0022] FIG. 9 is a flowchart illustrating an example of a charge management process. This process is executed by the processing unit 61 of the management device 60. In the charge management process, the processing unit 61 first determines whether any AGV 10 has started operation (S100). The processing unit 61 determines that any AGV 10 has started operation when, for example, the time when a predetermined operation time starts (9:00 p.m. as described above) or when charging is determined to be completed in the process described below and the AGV 10 departs from the charging area 80. If the processing unit 61 determines that any AGV 10 has started operation, the processing unit 61 acquires the remaining battery capacity B of the battery 37 of the AGV 10 as the remaining battery capacity B0 at the start of operation (S110), starts measuring the elapsed operation time T (actual operation time) of the AGV 10 (S120), and proceeds to S130. If the processing unit 61 determines that any AGV 10 has started operation, the processing unit 61 skips S110 and S120 and proceeds to S130.

[0023] Next, the processing unit 61 determines whether it is time to start charging (S130). The timing to start charging may be, for example, every predetermined time after the start of a predetermined operating time, or may be a time when the automatic transport operation ends, such as when the cart 100 reaches its destination. If the processing unit 61 determines that it is time to start charging, it executes a charging start determination process (S140) and proceeds to S150. If the processing unit 61 determines that it is not time to start charging, it skips S140 and proceeds to S150.

[0024] Next, the processing unit 61 determines whether it is time to determine whether charging has ended (S150). The timing to determine whether charging has ended may be, for example, every predetermined time when there is an automated guided vehicle 10 being charged in the charging area 80. If the processing unit 61 determines that it is time to determine whether charging has ended, it executes charging end determination processing (S160) and proceeds to S170. If the processing unit 61 determines that it is not time to determine whether charging has ended, it skips S160 and proceeds to S170.

[0025] Then, the processing unit 61 determines whether it is time to end the operation (S170). The operation end timing is, for example, the time when a predetermined operation period ends (such as 5:00 a.m. as described above). If the processing unit 61 determines that it is time to end the operation, it executes operation end processing (S180) and ends the charge management processing. If it determines that it is not time to end the operation, it returns to S100.

[0026] The charging start determination process of S140 is performed based on the flowchart of FIG. 10 . In the charging start determination process, the processing unit 61 first acquires the remaining battery capacity B of the battery 37 of the operating AGV 10 (S200) and determines whether the remaining battery capacity B is equal to or less than a first start threshold S1 for determining whether the battery capacity B is equal to or less than a first start threshold S1 for determining whether the battery capacity B is equal to or less than a predetermined remaining capacity, such as 20% or 30% (S210). The first start threshold S1 is a constant (fixed) value set to a predetermined remaining capacity, such as 20% or 30%, and is also referred to as a fixed threshold for determining whether the charging start is to be performed. In this embodiment, a fixed value is used as the threshold for determining whether the charging start is to be performed (first start threshold S1). However, a threshold that can be changed based on elapsed time T (remaining time Tr, described later), the operating status of the AGV 10, or other conditions may also be used. If the processing unit 61 determines that the remaining battery capacity B is not equal to or less than the first start threshold S1, the processing unit 61 determines not to start charging, i.e., to continue operation (S220), and ends the charging start determination process.

[0027] On the other hand, when the processing unit 61 determines that the remaining battery charge B is equal to or less than the first start threshold S1, it determines to start charging and instructs the automated guided vehicle 10 to move to the charging area 80 (S230). Note that if the charging start determination process is executed at a timing other than a break in the automated guided vehicle operation, the automated guided vehicle 10 may be instructed to move at a break in the automated guided vehicle operation. When the automated guided vehicle 10 receives the instruction in S230 and moves to the charging area 80 and stops, charging of the battery 37 starts.

[0028] Next, the processing unit 61 stores the battery consumption amount ΔB and the elapsed time T of the automated guided vehicle 10 that has been instructed to move (for which charging has started) in the storage unit 62 (S240), and ends the charging start determination process. The battery consumption amount ΔB is stored as the amount obtained by subtracting the current battery remaining amount B obtained in S200 from the battery remaining amount B0 at the start of operation of the automated guided vehicle 10 obtained in S110. Furthermore, the elapsed time T is stored as the time from when measurement is started in S120 to when charging start is determined in S230. Note that if there are multiple automated guided vehicles 10 in operation, the processing unit 61 performs the charging start determination process for each automated guided vehicle 10.

[0029] The charging end determination process of S160 is performed based on the flowchart of FIG. 11 . In the charging end determination process, the processing unit 61 first acquires the remaining battery capacity B of the battery 37 of the automatic guided vehicle 10 being charged (S300). The processing unit 61 also acquires the battery consumption rate (power consumption rate) P (% / H) corresponding to the operation information (S310) and the remaining time Tr (H) (S320). As will be described later, the processing unit 61 calculates the battery consumption rate P at the end of operation and stores it in the storage unit 62 in association with the operation information. Therefore, the processing unit 61 acquires the battery consumption rate P corresponding to the current (today's) operation information from the storage unit 62. The processing unit 61 also acquires the remaining time Tr, which is the time remaining until the end of the operation, for example, until 5:00 a.m., based on the current time.

[0030] Next, the processing unit 61 multiplies the battery consumption rate P by the remaining time Tr to set a second termination threshold E2 for determining the end of charging (S330). The processing unit 61 then determines whether the remaining battery capacity B exceeds a first termination threshold E1 for determining the end of charging (S340) and whether it exceeds a second termination threshold E2 for determining the end of charging (S350). The first termination threshold E1 is a constant value (fixed value) set to a predetermined remaining capacity, such as 70% or 80%, and is also referred to as a fixed threshold for determining the end of charging. If the processing unit 61 determines that the remaining battery capacity B does not exceed the first termination threshold E1 or the second termination threshold E2, it determines not to terminate charging, i.e., to continue charging (S360), and ends the charging end determination process.

[0031] On the other hand, when the processing unit 61 determines that the remaining battery charge B exceeds the first termination threshold E1, or determines that the remaining battery charge B exceeds the second termination threshold E2 even if it does not exceed the first termination threshold E1, it determines that charging should be terminated and instructs the automatic guided vehicle 10 to resume operation (S370), thereby terminating the charging termination determination process. Note that if there are multiple automatic guided vehicles 10 currently charging, the processing unit 61 performs the charging termination determination process for each automatic guided vehicle 10. Upon receiving the instruction in S370, the automatic guided vehicle 10 departs from the charging area 80 and resumes operation (automatic transport).

[0032] FIG. 12 is an explanatory diagram showing an example of the relationship between the first termination threshold E1 and the second termination threshold E2. In FIG. 12, the horizontal axis represents the remaining time Tr, and the vertical axis represents the remaining battery capacity B. Note that the remaining time Tr decreases toward the right side of the figure. The first termination threshold E1 is a fixed value set to a predetermined remaining capacity and remains constant regardless of the remaining time Tr. On the other hand, the second termination threshold E2 is set by multiplying the battery consumption rate P by the remaining time Tr, and therefore changes to a smaller value as the remaining time T decreases. For this reason, the second termination threshold E2 is also referred to as a change threshold for determining the end of charging. In this embodiment, at the start of operation, the remaining time Tr is relatively long, so the second termination threshold E2 is larger than the first termination threshold E1. However, after the predetermined remaining time Tr1, the remaining time Tr decreases, and the second termination threshold E2 becomes smaller than the first termination threshold E1. Therefore, after the remaining time Tr1, if the remaining battery capacity B of the automatic guided vehicle 10 being charged does not reach the first termination threshold E1 but exceeds the second termination threshold E2, it is determined that charging has ended (the shaded area in the figure). This increases the number of opportunities to determine that charging has ended compared to when charging end is determined based solely on the first termination threshold E1, making it easier to resume operation of the automatic guided vehicle 10 and improving the availability rate.

[0033] The operation termination process of S180 is performed based on the flowchart of FIG. 13 . In the operation termination process, the processing unit 61 acquires the remaining battery charge B of all AGVs 10 (S400), and acquires the total elapsed time T of the currently terminated operation and the total battery consumption ΔB (S410). In S410, the sum of the elapsed time T from the start of measurement in S120 until the processing of S410 is performed and the elapsed time T stored in the storage unit 62 in S240 is acquired. The sum of the elapsed times T of the multiple AGVs 10 is also acquired. In S410, the sum of the battery consumption ΔB obtained by subtracting the remaining battery charge B at the end of the operation (currently) from the remaining battery charge B0 at the start of the operation acquired in S110 and the battery consumption ΔB stored in S240 is also acquired. The sum of the battery consumption ΔB of the multiple AGVs 10 is also acquired.

[0034] Next, the processing unit 61 calculates the battery consumption rate P as the average consumption rate of the battery 37 per unit time during the operation time by dividing the total value of the battery consumption amount ΔB by the total value of the elapsed time T (S420). Subsequently, the processing unit 61 stores the calculated battery consumption rate P in the storage unit 62 in association with the operation information of the operation that has just ended (S430), and ends the operation end processing.

[0035] In this embodiment, as shown in FIG. 14 , the battery consumption rate P is associated with information on the day of the week of the working day (the day of the week when the working day started) and registered as operation information. Therefore, in S310 of the charging end determination process described above, the processing unit 61 acquires the battery consumption rate P corresponding to the day of the week of the current working day. Here, in the conveying system 1 of this embodiment, the load of the conveying work, such as the type (weight) and quantity of the cargo to be conveyed, varies depending on the day of the week, and the battery consumption rate P has a certain tendency. Therefore, by storing the battery consumption rate P in association with the information on the day of the week and using the battery consumption rate P corresponding to the day of the week when setting the second end threshold E2, an appropriate end threshold according to the load of the conveying work can be set. This allows for more appropriate determination of the end of charging of the battery 37.

[0036] Here, the correspondence between the components of this embodiment and the components of the present disclosure will be clarified. The processing unit 61 of the management device 60 that executes the charging end determination process of S160 of the charging management process of this embodiment corresponds to the charging end determination unit of the present disclosure. The memory unit 62 of the management device 60 corresponds to the memory unit. The processing unit 61 of the management device 60 that executes the charging start determination process of S140 of the charging management process corresponds to the charging start determination unit. In this embodiment, an example of a charging management device of the present disclosure is also clarified by explaining the operation of the transportation system 1 (management device 60).

[0037] In the transport system 1 according to the embodiment described above, the processing unit 61 sets the second termination threshold E2 so that it decreases as the remaining time Tr until the end of the operating time decreases, and determines the end of charging the battery 37 based on the remaining battery capacity B and the second termination threshold E2. Therefore, even if the remaining battery capacity B remains the same, depending on the remaining time Tr, it is possible to terminate charging and resume operation of the automated guided vehicle 10, thereby increasing the time that the automated guided vehicle 10 transports objects and improving the operating rate.

[0038] Furthermore, since the processing unit 61 sets the second termination threshold E2 by multiplying the battery consumption rate P by the remaining time Tr, the second termination threshold E2 for determining the remaining battery capacity B required for operation during the remaining time Tr can be set appropriately and without excess or deficiency. Note that the second termination threshold E2 may be set based on the value obtained by multiplying the battery consumption rate P by the remaining time Tr, for example, by adding a minimum remaining capacity that should be secured as a margin to the value obtained by multiplying the battery consumption rate P by the remaining time Tr. In this way, even if there is some variation in the load of the transport operation, the automated guided vehicle 10 whose charging has been determined to be completed based on the second termination threshold E2 can be operated more reliably until the end of the operating time.

[0039] Furthermore, the processing unit 61 associates the battery consumption rate P calculated based on the battery consumption rate ΔB during the previous operation with operation information (day of the week in this embodiment) related to the previous operation and stores it in the storage unit 62. The processing unit 61 then acquires and uses the battery consumption rate P corresponding to the operation information related to the current operation from the storage unit 62. Therefore, the second termination threshold E2 reflecting the tendency of the battery consumption rate P during the previous operation can be set, thereby making it possible to appropriately determine whether to terminate charging.

[0040] Furthermore, the processing unit 61 determines the end of charging when the remaining battery capacity B is greater than either the first end threshold E1 or the second end threshold E2, using a first end threshold E1 that is constant regardless of the remaining time Tr and a second end threshold E2 that changes depending on the remaining time Tr. Therefore, the end of charging can be appropriately determined using two thresholds, such as determining the end of charging based on the first end threshold E1 even when the second end threshold E2 is large because the remaining time Tr is long.

[0041] It goes without saying that the present disclosure is not limited to the above-described embodiments, and can be embodied in various forms as long as they fall within the technical scope of the present disclosure.

[0042] For example, in the above-described embodiment, the processing unit 61 stores the battery consumption rate P in association with the day of the week, and sets the second termination threshold E2 using the battery consumption rate P corresponding to the day of the week of the current operation, but this is not limited to this. The battery consumption rate P may be associated with other operation information, not limited to the day of the week. For example, if the type of cargo to be transported varies depending on the operation day, the type of cargo may be associated as operation information.

[0043] Alternatively, the battery consumption rate P is not limited to being associated with the operation information. For example, the processing unit 61 may calculate a cumulative value of the battery consumption amount ΔB and the elapsed time T each time the operation end process is performed, update and store the battery consumption rate P based on these cumulative values, and set the second end threshold E2 using the battery consumption rate P regardless of the operation information. Furthermore, in a transport system 1 having a plurality of AGVs 10, the processing unit 61 may associate the battery consumption rate P with each AGV 10. That is, the processing unit 61 may calculate the battery consumption rate P for each AGV 10, associate it with each AGV 10, and store it in the storage unit 62, and set the second end threshold E2 for each AGV 10 using the battery consumption rate P corresponding to the AGV 10 currently being charged. Furthermore, the processing unit 61 may associate the battery consumption rate P with the operation information and the AGV 10.

[0044] In the embodiment, the battery consumption rate P is calculated in the operation end processing. However, this is not limited thereto. As shown in a modified example of FIG. 15 , the battery consumption rate P may be calculated in the charge start determination processing. In this modified example, following the processing of S240, the processing unit 61 calculates the battery consumption rate P by dividing the battery consumption amount ΔB since the start of operation by the elapsed time T since the start of operation (S250), and then ends the charge start determination processing. As a result, the processing unit 61 can set the second end threshold E2 that reflects the battery consumption rate P during the current operation, and appropriately determine the end of charging. Note that, if the processing unit 61 has calculated the battery consumption rate P in the previously executed charge start determination processing, the processing unit 61 may update (calculate) the battery consumption rate P by including the current battery consumption amount ΔB and the elapsed time T.

[0045] 15 , the processing unit 61 calculates the battery consumption rate P in the charging start determination process, but this is not limited thereto. Before setting the second termination threshold E2 in the charging termination determination process, the processing unit 61 may calculate the battery consumption rate P based on the battery consumption amount ΔB at that time or the elapsed time T. In this way, when the battery consumption rate P is calculated in a process other than the operation termination process, the operation termination process in S180 of the charge management process may be omitted. Note that the battery consumption rate P is not limited to being calculated in the operation termination process or the process during operation, but may be determined in advance based on the specifications of the automatic guided vehicle 10 and the battery 37, or may be determined in advance based on experiments, etc.

[0046] In the embodiment, the processing unit 61 sets the threshold value for determining whether charging should be terminated (second termination threshold value E2) based on the battery consumption rate P and the remaining time Tr. However, as shown in the modified example of Fig. 16, a threshold value for determining whether charging should be initiated may be set. In this modified example, after acquiring the remaining battery capacity B of the operating automatic guided vehicle 10 in S200, the processing unit 61 acquires the battery consumption rate P according to the operation information (S202) and also acquires the remaining time Tr (S204). Next, the processing unit 61 multiplies the battery consumption rate P by the remaining time Tr to set the second start threshold value S2 for determining whether charging should be initiated (S206).

[0047] Next, the processing unit 61 determines whether the remaining battery capacity B is equal to or less than the first start threshold S1 (S210) and whether it is equal to or less than the second start threshold S2 (S212). If the processing unit 61 determines that the remaining battery capacity B is equal to or less than the first start threshold S1 and the second start threshold S2, the processing unit 61 proceeds to S230 and determines to start charging. On the other hand, if the processing unit 61 determines that the remaining battery capacity B is equal to or less than the first start threshold S1 but not equal to or less than the second start threshold S2, the processing unit 61 proceeds to S220 and determines not to start charging.

[0048] In this modification, the processing unit 61 sets the second start threshold S2 so that it decreases as the remaining time Tr decreases, and determines whether to start charging the battery 37 based on the remaining battery capacity B and the second start threshold S2. Therefore, even if the remaining battery capacity B is the same, depending on the remaining time Tr, the automatic guided vehicle 10 can continue operating without determining whether to start charging, thereby increasing the time that the automatic guided vehicle 10 transports an object and improving the operating rate.

[0049] In a modified example, the processing unit 61 uses a first start threshold S1 that is constant regardless of the remaining time Tr and a second start threshold S2 (a variable threshold for determining whether to start charging) that changes depending on the remaining time Tr to determine whether to start charging when the remaining battery capacity B is equal to or less than the first start threshold S1 and the second start threshold S2. Therefore, even if the remaining time Tr is long and the second start threshold S2 is large, the processing unit 61 determines not to start charging unless the remaining battery capacity B is equal to or less than the first start threshold S1. Furthermore, when the remaining time Tr is short and the second start threshold S2 is small, the processing unit 61 determines not to start charging unless the remaining battery capacity B is equal to or less than the second start threshold S2, even if the remaining battery capacity B is equal to or less than the first start threshold S1, thereby allowing the automatic guided vehicle 10 to continue operating. In this way, the processing unit 61 can appropriately determine whether to start charging using two start thresholds.

[0050] In the modified example of Fig. 16 , the battery consumption rate P may be calculated as in the modified example of Fig. 15 . That is, the processing unit 61 may execute the processes of S240 and S250 in Fig. 15 instead of the process of S202 in Fig. 16 . In this way, the processing unit 61 can set the second start threshold S2 that reflects the battery consumption rate P during the current operation, and appropriately determine whether to start charging.

[0051] In the embodiment, the processing unit 61 determines the end of charging using the first termination threshold E1 and the second termination threshold E2. However, this is not limited to this, and the first termination threshold E1 may not be used. However, when the second termination threshold E2 is set by multiplying the battery consumption rate P and the remaining time Tr, it is preferable to use the first termination threshold E1 to appropriately determine the end of charging. Furthermore, the processing unit 61 is not limited to comparing the first termination threshold E1 and the second termination threshold E2 with the remaining battery capacity B, and may compare the smaller of the first termination threshold E1 and the second termination threshold E2 with the remaining battery capacity B. Furthermore, the processing unit 61 may previously determine the remaining time Tr1 (see FIG. 12 ) at which the second termination threshold E2 becomes equal to or less than the first termination threshold E1, and use the first termination threshold E1 until the remaining time Tr1 is reached, and use the second termination threshold E2 after the remaining time Tr1.

[0052] In the embodiment, the processing unit 61 sets the second termination threshold E2 based on the product of the battery consumption rate P and the remaining time Tr, but this is not limited thereto. The second termination threshold E2 may be set so that it decreases as the remaining time Tr until the end of the operating time decreases. For example, the relationship between the remaining time Tr and the second termination threshold E2 may be stored in advance as a map in the storage unit 62, and when the remaining time Tr is given, the corresponding second termination threshold E2 may be derived and set from the map. Note that the map may have a relationship such as that shown in FIG. 12 that is predetermined based on the specifications of the automatic guided vehicle 10 and the battery 37, experiments, or the like. Alternatively, a relationship may be defined such that the second termination threshold E2 decreases in stages.

[0053] This specification also discloses the technical idea of ​​changing the "conveying system according to claim 1 or 2" in claim 5, which was originally filed, to "a conveying system according to any one of claims 1 to 4," and the technical idea of ​​changing the "conveying system according to claim 1 or 2" in claim 6, which was originally filed, to "a conveying system according to any one of claims 1 to 5."

[0054] The present disclosure is applicable to the manufacturing industry of automated guided vehicles and transport systems.

[0055] 1 conveying system, 10 automated guided vehicle (AMR), 11 vehicle body, 21 wheels, 22 drive motor, 30 connecting portion, 31 lifting plate, 32, 33, 34 connecting pin, 35 lifting device, 36 contact detection sensor, 37 battery, 38 battery remaining capacity meter, 40 control unit, 41 memory unit, 42 communication unit, 51 camera unit, 52, 53 sensor unit, 54 light emitting unit, 60 management device, 61 processing unit, 62 memory unit, 63 communication unit, 64 timing unit, 80 charging area, 100 basket cart, 101 loading platform, 110 caster, C basket cart storage area, M marker, R shelf.

Claims

1. A transport system including an unmanned transport vehicle that transports an object using battery power, the transport system comprising: when operation of the unmanned transport vehicle is stopped during a specified operating time to charge the battery, a termination threshold is set so that the shorter the remaining time until the end of the operating time is, and a charge termination determination unit is provided that determines the termination of charging of the battery based on the remaining charge of the battery and the termination threshold.

2. The transportation system according to claim 1, wherein the charging completion determination unit sets the completion threshold value based on a value obtained by multiplying the consumption rate of the battery by the remaining time.

3. A conveying system as described in claim 2, further comprising a memory unit that stores the consumption rate calculated based on the amount of consumption of the battery during the previous specified operating time in correspondence with operation information regarding the previous operation, and the charging end determination unit obtains from the memory unit and uses the consumption rate corresponding to the operation information regarding the current operation.

4. The transportation system according to claim 2, wherein the charging end determination unit uses the consumption rate calculated by dividing the amount of consumption of the battery since the start of the operating time by the time since the start of the operating time.

5. A transportation system as described in claim 1 or 2, wherein the charging end determination unit uses a first end threshold that is constant regardless of the remaining time and a second end threshold as the end threshold, and determines the end of charging when the remaining charge of the battery is greater than either the first end threshold or the second end threshold.

6. The transportation system according to claim 1 or 2, further comprising a charge start determination unit that sets a start threshold value that decreases as the remaining time decreases, and determines whether to start charging the battery based on the remaining battery capacity and the start threshold value.

7. A charge management device for an automated guided vehicle that transports an object using battery power, comprising: when operation of the automated guided vehicle is stopped during a specified operating time to charge the battery, a termination threshold is set so that the shorter the remaining time until the end of the operating time is, and a charge termination determination unit is provided that determines the termination of charging of the battery based on the remaining charge of the battery and the termination threshold.

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