JP7222333B2 - Automated Guided Vehicles and Automated Guided Systems - Google Patents

Description

The present invention relates to an automatic guided vehicle and an automatic guided vehicle system.

An automatic guided vehicle for transporting containers at a port container terminal or the like is described in Patent Document 1, for example. The automatic guided vehicle described in Patent Literature 1 includes a travel motor and a secondary battery that serves as a power source for the travel motor. Charging of the secondary battery is performed by a charger provided at the container terminal.

JP 2018-203391 A

If the number of chargers is smaller than that of the automatic guided vehicles deployed at the container terminal, the order of charging is determined, and the secondary batteries are charged according to this order. The charger performs rapid charging so as to reduce the waiting time for charging the automatic guided vehicle. Thereby, the charging time of the secondary battery of each automatic guided vehicle can be shortened, and the automatic guided vehicle can be operated using fewer chargers than the automatic guided vehicle. However, rapid charging of the secondary battery accelerates deterioration of the secondary battery.

An object of the present invention is to provide an automatic guided vehicle and an automatic guided vehicle system capable of suppressing deterioration of a secondary battery.

An automatic guided vehicle that solves the above problems is an automatic guided vehicle that has more chargers than the chargers in an area that includes a charging station where the chargers are arranged and a travel route, and includes a travel motor and the A charging current or charging power for a secondary battery serving as a power source for a running motor, a state of charge estimating unit for estimating the state of charge of the secondary battery, and the charger for charging the secondary battery. A command unit that transmits a command value, a receiving unit that receives a command from a host system, a transmission unit that transmits information to the host system, and the automatic guided vehicle travels according to the travel route instruction from the host system. a transmission control unit for transmitting from the transmission unit to the upper system information capable of recognizing an expected arrival time, which is the time required for the automatic guided vehicle to reach the charger, and the charging a shortest arrival time obtaining unit that obtains, from the receiving unit, information capable of recognizing the shortest arrival time, which is the shortest of the estimated arrival times of other automatic guided vehicles, when the secondary battery is charged by the device. and the instruction unit reduces the instruction value as the shortest arrival time is longer.

Even if the secondary battery is charged by the charger until another automatic guided vehicle reaches the charger, waiting time for charging the other automatic guided vehicle is less likely to occur. Since it is expected that other automatic guided vehicles will not reach the charger during the shortest arrival time, it can be said that the shortest arrival time is the time during which the secondary battery can be charged by the charger. By decreasing the command value of the charging current or charging power as the shortest arrival time is longer, the secondary battery is charged with a smaller charging current or smaller charging power as the shortest arrival time is longer. The smaller the charging current, the more suppressed the deterioration of the secondary battery. Similarly, the lower the charging power, the more the deterioration of the secondary battery is suppressed. Therefore, by decreasing the command value to the charger when the shortest arrival time is long and the time that can be used for charging the secondary battery is long, the secondary battery can be charged faster than when the command value is always set to the maximum value. Deterioration can be suppressed.

A power consumption calculation unit that calculates the power consumption of the secondary battery for the automatic guided vehicle from the travel route, the weight of the automatic guided vehicle, and the average weight of the load conveyed by the automatic guided vehicle; Calculating the expected arrival time from the power consumption calculated by the power consumption calculating unit, the state of charge estimated by the state of charge estimating unit, and vehicle average efficiency considering loss caused by the automatic guided vehicle and an expected time calculation unit.

The expected arrival time is calculated by an automatic guided vehicle. Therefore, the load on the host system can be reduced compared to the case where the host system calculates the expected arrival time of the automatic guided vehicle.
An unmanned guided vehicle system for solving the above problems is an unmanned guided vehicle having more chargers than chargers in an area including a charging station where chargers are arranged and a travel route, and a command is sent to the unmanned guided vehicle. and a host system, wherein the automatic guided vehicle includes a traveling motor, a secondary battery serving as a power source for the traveling motor, and a state of charge of the secondary battery. a state-of-charge estimating unit; a command unit that transmits a command value of charging current or charging power to the charger that charges the secondary battery; a receiving unit that receives a command from the host system; a transmission unit that transmits information to a host system; a travel control unit that causes the unmanned guided vehicle to travel according to the travel route instruction from the host system; and a time required for the unmanned guided vehicle to reach the charger. and a transmission control unit that transmits from the transmission unit to the host system information that enables the estimated arrival time to be recognized; a shortest arrival time acquisition unit that acquires information from the receiving unit that enables recognition of the shortest arrival time, which is the shortest time among the times, and the command unit decreases the command value as the shortest arrival time is longer. The upper system includes a command transmission unit that transmits the command to the automatic guided vehicle, an information reception unit that receives the information transmitted from the transmission unit, and a command transmission unit that transmits the information to the automatic guided vehicle. and a shortest arrival time transmission control unit that transmits information that enables recognition of the shortest arrival time, wherein the automatic guided vehicle system receives the travel route, the weight of the automatic guided vehicle, and the weight of the load conveyed by the automatic guided vehicle. a power consumption calculation unit that calculates the power consumption of the secondary battery from the weight average value; the power consumption calculated by the power consumption calculation unit; the state of charge estimated by the state of charge estimation unit; and an expected arrival time calculation unit that calculates the expected arrival time from a vehicle average efficiency in consideration of loss caused by the automatic guided vehicle.

By reducing the command value to the charger when the shortest arrival time is long and the time available for charging the secondary battery is long, deterioration of the secondary battery is suppressed compared to when the command value is always set to the maximum value. can do.

In the automatic guided vehicle system, the automatic guided vehicle includes a temperature detection unit that detects the temperature of the secondary battery, and a temperature transmission control unit that transmits information indicating the temperature of the secondary battery from the transmission unit to the host system. and wherein the host system receives the shortest arrival time received by the automatic guided vehicle in which the temperature of the secondary battery is equal to or higher than a threshold value by the automatic guided vehicle in which the temperature of the secondary battery is less than the threshold. A charging order determining unit that determines a charging order so as to be longer than the shortest arrival time, and the charging order determined by the charging order determining unit is transmitted from the command transmitting unit to the automatic guided vehicle, and an order transmission control unit that causes the automatic guided vehicle to charge the secondary battery in the order determined by the charging order.

Since the host system can recognize the expected arrival time of the automatic guided vehicle, the shortest arrival time received by the automatic guided vehicle whose secondary battery temperature is above the threshold is the The charging order can be determined to be longer than the shortest arrival time received. In other words, the host system can determine the charging order so as to secure a long charging time when charging the secondary battery whose temperature is equal to or higher than the threshold using the charger. The longer the shortest arrival time, the longer the time during which the secondary battery can be charged by the charger. Since the longer the shortest arrival time, the smaller the command value of the charging current, it is possible to suppress the temperature rise of the secondary battery whose temperature is equal to or higher than the threshold. Therefore, deterioration of the secondary battery can be suppressed.

ADVANTAGE OF THE INVENTION According to this invention, deterioration of a secondary battery can be suppressed.

The figure which shows typically the container terminal where an automatic guided vehicle is used. Schematic configuration diagram of an automatic guided vehicle. 4 is a flowchart showing processing performed while the automatic guided vehicle is running; 4 is a flow chart showing processing performed when an automatic guided vehicle is connected to a charger; 9 is a flow chart showing processing performed in the control tower of the second embodiment; The figure for demonstrating the effect|action of 2nd Embodiment. The figure for demonstrating the effect|action of 2nd Embodiment. The figure for demonstrating the effect|action of 2nd Embodiment.

(First embodiment)
A first embodiment of an automatic guided vehicle and an automatic guided vehicle system will be described below.
As shown in FIG. 1 , the automatic guided vehicle system TS includes an automatic guided vehicle 10 and a control tower 51 . The automatic guided vehicle 10 is used at a container terminal T in a harbor. A plurality of predetermined travel routes R1, R2, and R3 are set in the container terminal T. As shown in FIG. The automatic guided vehicle 10 travels along one of the travel routes R1, R2, and R3 according to a command from the control tower 51. FIG. In this embodiment, three travel routes are provided. Assuming that the three traveling routes R1, R2, and R3 are respectively a first traveling route R1, a second traveling route R2, and a third traveling route R3, the traveling distance [m] of the first traveling route R1 is the shortest, and the traveling distance [m] of the third traveling route R1 is the shortest. The travel distance of the route R3 is the longest. The travel distance of the second travel route R2 is the distance between the travel distance of the first travel route R1 and the travel distance of the second travel route R2. In the container terminal T, a loading position P1 for loading the container C on the automatic guided vehicle 10 and a charging site P2 where the charger 61 is arranged are set. The loading position P1 is provided at a quay where the container ship CS can dock. One charger 61 is provided in the charging field P2. In this embodiment, the container terminal T is an area including travel routes R1, R2, R3 and a charging station P2.

A container terminal T is equipped with a plurality of automatic guided vehicles 10 . In this embodiment, four automatic guided vehicles 10 are deployed. It can be said that more automatic guided vehicles 10 are deployed than the number of chargers 61 . Each automatic guided vehicle 10 is loaded with containers C from a container ship CS by a gantry crane C1. A part of each traveling route R1, R2, R3 is common, and the loading position P1 is provided in this common part.

The automatic guided vehicle 10 loaded with the container C travels along the travel routes R1, R2, R3 to the rubber tire crane C2. The container C loaded on the automatic guided vehicle 10 is unloaded by the rubber tire crane C2. The unmanned guided vehicle 10 with the container C unloaded returns to the gantry crane C1 along the travel routes R1, R2 and R3. The travel distance of each travel route R1, R2, R3 is the distance traveled by the automatic guided vehicle 10 to return from the gantry crane C1 to the gantry crane C1 via the rubber tire crane C2.

As shown in FIG. 2, the automatic guided vehicle 10 includes a secondary battery 11, a voltage detector 12, a current detector 13, a temperature detector 14, an inverter 15, a traveling motor 16, and a battery ECU 21. , a vehicle ECU 31 , a wireless device 41 , and a charging port 42 . All automatic guided vehicles 10 have the same configuration.

Any secondary battery 11 may be used as long as it is chargeable and dischargeable, such as a lithium ion secondary battery or a nickel-hydrogen storage battery. A plurality of secondary batteries 11 are provided. A plurality of secondary batteries 11 are connected in series or in parallel. Moreover, the plurality of secondary batteries 11 may be formed by connecting a plurality of secondary batteries 11 into a module and connecting them in series or in parallel. That is, the connection mode of the plurality of secondary batteries 11 is arbitrary.

The voltage detection unit 12 detects the inter-terminal voltage for each of the plurality of secondary batteries 11 . A current detection unit 13 detects a discharging current from the secondary battery 11 and a charging current to the secondary battery 11 . The charging current includes charging current due to regeneration and charging current due to charging by the charger 61 . In the following description, the discharging current and charging current are collectively referred to as charging/discharging current. Temperature detector 14 detects the temperature of secondary battery 11 . The temperature detection unit 14 may be provided individually for each of the plurality of secondary batteries 11 , or may be provided for a plurality of representative secondary batteries 11 among all the secondary batteries 11 . Moreover, the number of the temperature detection parts 14 may be singular.

Inverter 15 converts the DC power input from secondary battery 11 into AC power and outputs the AC power to motor 16 for running. Note that the automatic guided vehicle 10 may include a converter that transforms the DC power of the secondary battery 11 and outputs it to the inverter 15 .

The traveling motor 16 is an AC rotary electric machine. The traveling motor 16 is connected to the inverter 15 . The traveling motor 16 operates as an electric motor when power is supplied from the inverter 15, and generates rotational driving force. The automatic guided vehicle 10 travels by transmitting this rotational driving force to the driving wheels through the axle. On the other hand, the traveling motor 16 operates as a generator during braking of the automatic guided vehicle 10 or during acceleration reduction on a downward slope, and performs regenerative power generation. Electric power generated by the traveling motor 16 is supplied to the secondary battery 11 through the inverter 15 . The secondary battery 11 serves as a power source for the running motor 16 .

Battery ECU21 is an electronic control unit provided with CPU22 and the memory|storage part 23 as hardware: Electronic Control Unit. The battery ECU 21 controls the secondary battery 11 such as monitoring the state of the secondary battery 11 . Various programs for controlling the secondary battery 11 are stored in the storage unit 23 . The CPU 22 executes various processes by referring to the storage unit 23 . CPU 22 may be configured as a circuit that includes one or more processors that operate according to a computer program, one or more dedicated hardware circuits such as ASICs, or combinations thereof. The storage unit 23 includes memories such as RAM and ROM. The memory stores program code or instructions configured to cause the CPU to perform processes. Memory, or computer-readable media, includes anything that can be accessed by a general purpose or special purpose computer.

The battery ECU 21 can acquire the detection result of the voltage detection unit 12, the detection result of the current detection unit 13, and the detection result of the temperature detection unit 14. The battery ECU 21 estimates the state of charge of the secondary battery 11 at predetermined control cycles. In this embodiment, the state of charge of the secondary battery 11 is the charging rate [%] of the secondary battery 11 . Estimation of the state of charge can be performed using various techniques. The estimation of the charging rate may be performed by a current integration method, which is a method of estimating the charging rate by integrating the charging/discharging current of the secondary battery 11, or the open circuit voltage of the secondary battery 11 and the charging rate. may be estimated from the correlation of The open circuit voltage of the secondary battery 11 can be estimated from the closed circuit voltage, which is the terminal voltage detected by the voltage detector 12 . The battery ECU 21 functions as a state-of-charge estimator. Note that the charging rate of the secondary battery 11 is the charging rate of an assembled battery in which all of the plurality of secondary batteries 11 are connected.

Vehicle ECU31 is provided with CPU32 and the memory|storage part 33 as hardware. The vehicle ECU 31 comprehensively controls the automatic guided vehicle 10 . The vehicle ECU 31 may be a combination of multiple ECUs that perform various controls. Various programs for controlling the automatic guided vehicle 10 are stored in the storage unit 33 . The storage unit 33 is composed of RAM, ROM, and the like. Similar to the battery ECU 21, the vehicle ECU 31 may comprise an application specific integrated circuit: ASIC. The vehicle ECU 31 may be configured as a circuit including one or more processors operating according to a computer program, one or more dedicated hardware circuits such as ASIC, or a combination thereof.

The vehicle ECU 31 causes the unmanned guided vehicle 10 to travel according to instructions from the control tower 51 regarding the travel routes R1, R2, and R3. The vehicle ECU 31 can cause the automatic guided vehicle 10 to travel along the travel routes R1, R2, and R3 by controlling the inverter 15 and the steering mechanism. Note that the vehicle ECU 31 reads the markers provided on the travel routes R1, R2, and R3 with sensors, so that the automatic guided vehicle 10 travels along the instructed travel routes R1, R2, and R3. good. The vehicle ECU 31 estimates its own position by self-position estimation using a global positioning system, odometry, Bayes filter, etc., and causes the automatic guided vehicle 10 to travel along the travel routes R1, R2, and R3. may That is, the vehicle ECU 31 may perform any travel control as long as the automatic guided vehicle 10 can be traveled along the travel routes R1, R2, and R3. In this embodiment, the vehicle ECU 31 functions as a travel control unit.

The battery ECU 21 and the vehicle ECU 31 can communicate with each other using protocols such as CAN: Controller Area Network and LIN: Local Interconnect Network. Thereby, the battery ECU 21 and the vehicle ECU 31 can obtain mutual information.

The wireless device 41 is a communication interface for communicating with the control tower 51 . For convenience of explanation, the wireless device 41 of the automatic guided vehicle 10 will be referred to as the first wireless device 41 in the following description. The first radio 41 is connected to the vehicle ECU 31 . The first radio device 41 includes a modulation unit that modulates data input from the vehicle ECU 31 to generate a radio signal, an antenna that transmits and receives radio signals, and a radio signal received from the control tower 51 that is demodulated and demodulated. and a demodulator that outputs the obtained data to the vehicle ECU 31 . The vehicle ECU 31 can generate data using a protocol communicable with the control tower 51 and transmit the data to the control tower 51 via the first radio 41 . This data includes, for example, information about the secondary battery 11, information about the automatic guided vehicle 10, and identification information. The identification information is individual information=ID assigned to each automatic guided vehicle 10 . Based on this identification information, the control tower 51 can recognize the unmanned guided vehicle 10 that has transmitted the data. The vehicle ECU 31 can acquire commands from the control tower 51 from the data demodulated by the first radio 41 . The first wireless device 41 functions as a receiver that receives commands from the control tower 51 and a transmitter that transmits information to the control tower 51 .

The control tower 51 includes a control section 52 and a wireless device 55 . The control tower 51 is a host system that gives commands to each automatic guided vehicle 10 . The control unit 52 has a CPU 53 and a storage unit 54 . The control unit 52 controls the automatic guided vehicle system TS by generating commands to be given to the automatic guided vehicles 10 . The storage unit 54 is composed of RAM, ROM, and the like. The controller 52 may comprise an application specific integrated circuit: ASIC. The controller 52 may be configured as a circuit including one or more processors operating according to a computer program, one or more dedicated hardware circuits such as ASICs, or a combination thereof.

The radio 55 is a communication interface for communicating with the first radio 41 . For convenience of explanation, the radio 55 of the control tower 51 will be referred to as the second radio 55 in the following description. The second radio 55 is connected to the control section 52 . The second radio device 55 includes a modulation unit that modulates data input from the control unit 52 to generate a radio signal, an antenna that transmits and receives radio signals, and a radio signal received from the first radio device 41 that is demodulated. , and a demodulator that outputs the demodulated data to the controller 52 . The control unit 52 generates data using a protocol that allows communication with the first radio device 41 and transmits the data to the first radio device 41 via the second radio device 55 . This data includes, for example, commands to the automatic guided vehicle 10 and identification information of the automatic guided vehicle 10 . By including identification information in the data, a command can be given from a plurality of automatic guided vehicles 10 used in the container terminal T to an arbitrary automatic guided vehicle 10 . The second wireless device 55 functions as a command transmitter that transmits commands to the automatic guided vehicle 10 and an information receiver that receives information transmitted from the first wireless device 41 .

Charging port 42 is an inlet connectable to charger 61 . Charging port 42 connects secondary battery 11 and charger 61 .
The charger 61 includes a power converter 62 that converts AC power supplied from an external power source, and a charge controller 63 that controls the charger 61 . The power converter 62 includes an inverter that converts AC power into DC power, a DC/DC converter that transforms the DC power, and the like.

The charging control unit 63 includes a CPU 64 and a storage unit 65 . The storage unit 65 is composed of RAM, ROM, and the like. The charging controller 63 may comprise an application specific integrated circuit: ASIC. Charging control unit 63 may be configured as a circuit including one or more processors operating according to a computer program, one or more dedicated hardware circuits such as ASIC, or a combination thereof. The charge control unit 63 charges the secondary battery 11 by controlling the power conversion unit 62 to output a charging current from the power conversion unit 62 .

The charger 61 includes a charging plug (not shown), and the charging plug is connected to the charging port 42 to connect the power conversion unit 62 and the secondary battery 11, and the charging control unit 63 and the vehicle ECU 31 are connected. be. As a result, the secondary battery 11 is charged with the DC power output from the power converter 62 . Further, the vehicle ECU 31 and the charging control unit 63 can communicate with each other.

Next, the control performed by the automatic guided vehicle 10 of this embodiment will be described. First, the control performed while the automatic guided vehicle 10 is running will be described.
As shown in FIG. 3 , in step S<b>1 , the vehicle ECU 31 acquires the travel route plan transmitted from the control tower 51 via the first radio 41 . The travel route planning indicates to the automatic guided vehicle 10 which travel route R1, R2, R3 the container C should be transported. The travel route plan may be a plan for one transportation of the container C or a plan for multiple transportations of the container C. FIG. That is, the vehicle ECU 31 may acquire the travel route plan each time the gantry crane C1 and the rubber tire crane C2 are reciprocated once, or may acquire the travel route plan each time the gantry crane C1 and the rubber tire crane C2 are reciprocated a plurality of times. A route plan may be obtained.

Next, in step S2, the vehicle ECU 31 calculates the travel distance from the travel routes R1, R2, and R3 instructed in the travel route plan. Travel distances corresponding to the travel routes R1, R2, and R3 are stored in advance in the storage unit 33 of the vehicle ECU 31 . That is, the travel distance when traveling along the first travel route R1, the travel distance when traveling along the second travel route R2, and the travel distance when traveling along the third travel route R3 are individually stored in the storage unit 33. remembered. The vehicle ECU 31 calculates the travel distance from the correspondence relationship between the travel routes R1, R2, and R3 stored in the storage unit 33 and the travel distance.

Next, in step S3, the vehicle ECU 31 calculates power consumption [kWh] from the travel distance calculated in step S2, the weight [kg] of the automatic guided vehicle 10, and the average weight value [kg] of the load. The weight of the automatic guided vehicle 10 is stored in the storage unit 33 of the vehicle ECU 31 or the storage unit 23 of the battery ECU 21 . The average weight of cargo is the average weight of a plurality of containers C that have been transported in the past. Note that the weight of the container C includes the weight of the cargo inside the container C. When the automatic guided vehicle 10 includes a weight detection unit that detects the weight of the container C, the vehicle ECU 31 acquires the weight of the container C from the weight detection unit each time the container C is loaded on the automatic guided vehicle 10, A weight average value of the load may be calculated. In this case, the calculated average weight of the load is stored in the storage unit 33 of the vehicle ECU 31 or the storage unit 23 of the battery ECU 21 . Also, the weight average value of the load may be transmitted from the control tower 51 as information included in a radio signal. By executing the processing of step S3, the vehicle ECU 31 functions as a power consumption calculation unit.

Next, in step S4, the vehicle ECU 31 calculates the power consumption calculated in step S3, the vehicle average efficiency, the full charge capacity [kWh] of the secondary battery 11, the charging rate [%] of the secondary battery 11, and the current The expected time of arrival at the charger 61 is calculated from the time. The full charge capacity of the secondary battery 11 is stored in the storage unit 23 of the battery ECU 21 or the storage unit 33 of the vehicle ECU 31 . The full charge capacity of the secondary battery 11 is the full charge capacity of an assembled battery in which all of the plurality of secondary batteries 11 are connected. The vehicle average efficiency is a value that takes into account losses occurring in the automatic guided vehicle 10, such as losses in the inverter 15 and tires, and is a coefficient that is multiplied by power consumption. The vehicle average efficiency is stored in the storage unit 33 of the vehicle ECU 31 or the storage unit 23 of the battery ECU 21 .

The vehicle ECU 31 corrects the power consumption calculated in step S3 with the vehicle average efficiency to calculate the corrected power consumption [kWh]. The post-correction power consumption is the power consumption that takes into account the loss that occurs in the automatic guided vehicle 10 . The vehicle ECU 31 can calculate the expected arrival time [h] to the charger 61 using the corrected power consumption. The expected arrival time is the expected time until the automatic guided vehicle 10 reaches the charger 61 . The expected arrival time is the time during which charging by the charger 61 can be performed before the remaining capacity [kWh] of the secondary battery 11 runs out. For example, if the remaining capacity of the secondary battery 11 is calculated by multiplying the charging rate of the secondary battery 11 by the full charge capacity of the secondary battery 11, and dividing the remaining capacity of the secondary battery 11 by the power consumption after correction, , the time [h] until the remaining capacity of the secondary battery 11 runs out can be calculated. If the estimated time of arrival is set so that charging by the charger 61 can be performed one hour before the time when the remaining capacity of the secondary battery 11 runs out, the time required to move to the charger 61 plus one hour. is subtracted from the time until the remaining capacity of the secondary battery 11 runs out. Thus, the expected arrival time can be calculated using the corrected power consumption. Further, when the automatic guided vehicle 10 is directed to the charger 61 triggered by the charging rate of the secondary battery 11 falling below 20%, the charge obtained by subtracting 20% from the charging rate of the secondary battery 11 By multiplying the full charge capacity of the secondary battery 11 by the rate, the usable capacity [kWh] of the secondary battery 11 that can be used until the charging rate of the secondary battery 11 reaches 20% can be calculated. By dividing the usable capacity of the secondary battery 11 by the corrected power consumption, the time until the charging rate of the secondary battery 11 reaches 20% can be calculated. Then, by adding the time required for moving to the charger 61 to the time until the charging rate of the secondary battery 11 reaches 20%, the expected arrival time can be calculated. The vehicle ECU 31 functions as an estimated arrival time calculator by executing the process of step S4.

As described above, the expected arrival time may be set arbitrarily as long as the time allows charging by the charger 61 until the remaining capacity of the secondary battery 11 is exhausted. In the above example, the expected arrival time is calculated so that the charger 61 is reached one hour before the remaining capacity of the secondary battery 11 runs out. , may be changed to an arbitrary time to calculate the expected arrival time. Similarly, in the above example, when the charging rate of the secondary battery 11 falls below 20%, the expected arrival time of the automatic guided vehicle 10 toward the charger 61 is calculated. Alternatively, the expected arrival time may be calculated by changing the charging rate to an arbitrary one such as 10% or 30%.

The vehicle ECU 31 calculates the expected arrival time by adding the calculated expected arrival time to the current time. The expected arrival time is the time when the automatic guided vehicle 10 is expected to reach the charger 61 .

Next, in step S<b>5 , the vehicle ECU 31 transmits information indicating the expected arrival time to the control tower 51 via the first radio device 41 . The control tower 51 receives the information indicating the expected arrival times for the number of automatic guided vehicles 10 deployed at the container terminal T. FIG. Note that the expected arrival time is a value obtained by adding the expected arrival time to the current time, so the expected arrival time can be derived from the expected arrival time. The information indicating the expected arrival time can be said to be information that enables recognition of the expected arrival time. By executing the processing of step S5, the vehicle ECU 31 functions as a transmission control section. The vehicle ECU 31 also transmits information indicating the charging rate of the secondary battery 11 to the control tower 51 via the first radio 41 . The processes of steps S1 to S5 are repeated at a predetermined control cycle while the automatic guided vehicle 10 is running.

Next, the automatic guided vehicle 10 is connected to the charger 61 and the control performed by the automatic guided vehicle 10 when the secondary battery 11 is charged by the charger 61 will be described.
As shown in FIG. 4, in step S11, the vehicle ECU 31 obtains information indicating the charging rate of the secondary battery 11 of the other automatic guided vehicle 10 and the expected arrival time of the other automatic guided vehicle 10 at the charger 61. The information shown is acquired from the first wireless device 41 . The other automatic guided vehicle 10 is the automatic guided vehicle 10 that is not connected to the charger 61, and can also be said to be the automatic guided vehicle 10 that is running. Information indicating the estimated arrival times of the other automatic guided vehicles 10 is transmitted from the control tower 51 . The control tower 51 may transmit information indicating the expected arrival times of the other automatic guided vehicles 10 to each automatic guided vehicle 10 at predetermined transmission intervals, or may send other information in response to a request from the automatic guided vehicle 10 . Information indicating the expected arrival time of the automatic guided vehicle 10 may be transmitted. When the control tower 51 transmits information indicating the estimated arrival time of another automatic guided vehicle 10 in response to a request from the automatic guided vehicle 10, the vehicle ECU 31 sets the first wireless device before performing the process of step S11. 41, the control tower 51 is requested to transmit information indicating the estimated time of arrival of the other automatic guided vehicle 10. FIG. In this embodiment, the vehicle ECU 31 acquires information indicating the estimated arrival time of each of the three automatic guided vehicles 10 that are not connected to the charger 61 and information indicating the charging rate of the secondary battery 11 . be. Thereby, the vehicle ECU 31 recognizes the expected arrival time of each automatic guided vehicle 10 and the charging rate of the secondary battery 11 .

Next, in step S<b>12 , the vehicle ECU 31 calculates a charging current Y that can fully charge the secondary battery 11 by the time another automatic guided vehicle 10 reaches the charger 61 . First, the vehicle ECU 31 predicts the arrival of the automatic guided vehicle 10 that reaches the charger 61 earliest from the estimated arrival time of the automatic guided vehicle 10 that reaches the charger 61 earliest among the other automatic guided vehicles 10 and the current time. Calculate time. The expected arrival time is the time from the current time to the expected arrival time. The expected arrival time of the automatic guided vehicle 10 that reaches the charger 61 earliest is the shortest expected arrival time of the other automatic guided vehicles 10 . The vehicle ECU 31 can derive the expected arrival time from the expected arrival time of the other automatic guided vehicle 10 acquired in step S11. Further, the vehicle ECU 31 can derive the shortest arrival time from the expected arrival times of the other automatic guided vehicles 10 acquired in step S11. The information with which the shortest arrival time can be recognized can be said to be information indicating the expected arrival times of the other automatic guided vehicles 10 . It can be said that the vehicle ECU 31 of each automatic guided vehicle 10 transmits information for recognizing the shortest arrival time of the other automatic guided vehicles 10 to the vehicle ECU 31 of the automatic guided vehicle 10 to be charged by the charger 61 . It can be said that vehicle ECU31 is functioning as a shortest arrival time acquisition part by performing the process of step S11. In addition, it can be said that the control unit 52 that transmits the information enabling recognition of the shortest arrival time from the second wireless device 55 to the automatic guided vehicle 10 functions as a shortest arrival time transmission control unit.

The vehicle ECU 31 calculates the charging current Y so that the longer the shortest arrival time, the smaller the charging current Y. A charging current Y is a current that flows through the secondary battery 11 when the secondary battery 11 is charged by the charger 61 . In other words, the charging current Y is the current output from the power converter 62 . For example, the vehicle ECU 31 calculates the charging current Y so that the estimated arrival time of the automatic guided vehicle 10 that reaches the charger 61 earliest and the time when the secondary battery 11 is fully charged are the same. The vehicle ECU 31 can calculate the charging capacity required for full charging from the charging rate of the secondary battery 11 and the full charging capacity of the secondary battery 11 . The vehicle ECU 31 calculates the charging current Y such that the estimated arrival time of the automatic guided vehicle 10 that reaches the charger 61 earliest and the time when the secondary battery 11 is fully charged are the same from the charging capacity and the shortest arrival time. can do. Note that the calculation of the charging current Y described above may be calculated including a margin and various coefficients. For example, the vehicle ECU 31 may calculate the charging current Y so that the secondary battery 11 is fully charged at a time slightly earlier than the expected arrival time of the automatic guided vehicle 10 that reaches the charger 61 earliest. Any method of calculating the charging current Y may be used as long as the charging current Y can be calculated such that the longer the shortest arrival time, the smaller the charging current Y.

Next, in step S<b>13 , the vehicle ECU 31 determines whether or not the charging current Y calculated in step S<b>12 is within the specification range of the secondary battery 11 . The specification range of the secondary battery 11 is a range in which the charging current Y can be allowed. The specification range is set to suppress deterioration of the secondary battery 11 due to an excessively large charging current Y and to suppress an excessively long charging time due to an excessively small charging current Y. ing. When the determination result of step S13 is affirmative, vehicle ECU31 processes step S14. On the other hand, when the determination result of step S13 is negative, the vehicle ECU 31 performs the process of step S15.

In step S<b>14 , the vehicle ECU 31 transmits the charging current Y calculated in step S<b>12 as a command value Y to the charging control unit 63 . The vehicle ECU 31 functions as a command unit that transmits the command value of the charging current to the charger 61 by performing the process of step S14. In step S15, the vehicle ECU 31 transmits the charging current within the specification range to the charging control unit 63 as the command value Y1. For the charging current within the specification range, for example, if the charging current Y calculated in step S12 exceeds the upper limit of the specification range, the upper limit of the specification range is used as the command value. If the charging current Y calculated in step S12 is below the lower limit of the specification range, the lower limit of the specification range is set as the command value. The command value Y1 may be any value as long as the charging current is within the specification range.

When the command value of the charging current is transmitted to the charging control unit 63 by the process of step S14 or step S15, the charging control unit 63 controls the power conversion unit 62 so that the charging current according to the command value is output. conduct. As a result, the secondary battery 11 is charged with a smaller charging current as the shortest arrival time is longer. The processes of steps S11 to S15 are repeatedly performed at a predetermined control cycle while the automatic guided vehicle 10 is connected to the charger 61 .

As described above, at least one of the battery ECU 21 and the vehicle ECU 31 predetermines the state-of-charge estimating unit, the command unit, the running control unit, the transmission control unit, the shortest arrival time acquisition unit, the power consumption calculation unit, and the expected arrival time calculation unit. It is a functional part that functions by executing the program that is specified. Also, the shortest arrival time transmission control unit is a functional unit that functions when the control unit 52 executes a predetermined program.

The operation of the first embodiment will be described.
Each automatic guided vehicle 10 used in the container terminal T transmits information indicating the estimated arrival time to the charger 61 to the control tower 51 . Therefore, when one of the automatic guided vehicles 10 charges the secondary battery 11 by the charger 61, the control tower 51 determines the shortest arrival time for the automatic guided vehicle 10 to be charged. can transmit recognizable information. When the secondary battery 11 of the automatic guided vehicle 10 is charged by the charger 61, even if the secondary battery 11 is charged by the charger 61 until the other automatic guided vehicle 10 reaches the charger 61, other Waiting time for charging the automatic guided vehicle 10 is less likely to occur. Since other automatic guided vehicles 10 do not reach the charger 61 during the shortest arrival time, it can be said that the shortest arrival time is the time during which the secondary battery 11 can be charged. By decreasing the command value of the charging current as the shortest arrival time is longer, the secondary battery 11 is charged with a smaller charging current as the shortest arrival time is longer.

Effects of the first embodiment will be described.
(1-1) The deterioration of the secondary battery 11 is suppressed as the charging current for charging the secondary battery 11 decreases. For this reason, when the shortest arrival time is long and the time that can be used for charging the secondary battery 11 is long, the command value to the charger 61 is reduced so that the command value to the charger 61 is always the maximum value. The deterioration of the secondary battery 11 can be suppressed as compared with .

(1-2) The smaller the charging current for charging the secondary battery 11 is, the smaller the amount of heat generated by the secondary battery 11 is. If the secondary battery 11 were to be charged at a constant rate of rapid charging, the temperature of the secondary battery 11 would rise sharply, causing deterioration of the secondary battery 11 to be accelerated. By reducing the charging current when charging the secondary battery 11, the temperature rise of the secondary battery 11 can be suppressed, and the deterioration of the secondary battery 11 can be further suppressed. Moreover, since the temperature rise of the secondary battery 11 can be suppressed, the cooling device for cooling the secondary battery 11 can be simplified.

(1-3) If rapid charging is always performed by the charger 61 regardless of the shortest arrival time of the other automatic guided vehicles 10, the usage time of the charger 61 is short and the charger 61 is not used. The unused time that is the time is long. The charger 61 is not used even though there is time for charging by the charger 61, and it cannot be said that the charger 61 is being used efficiently. On the other hand, in the present embodiment, the usage time of the charger 61 is increased in proportion to the shortest arrival time of the other automatic guided vehicles 10, so the time during which the charger 61 is not used is shortened. The unused time of the charger 61 is reduced, and the charger 61 can be used efficiently.

(Second embodiment)
A second embodiment of an automatic guided vehicle and an automatic guided vehicle system will be described below. In addition, description is abbreviate|omitted by attaching|subjecting the same code|symbol about the same part as 1st Embodiment.

In the second embodiment, the vehicle ECU 31 of the automatic guided vehicle 10 transmits information indicating the temperature of the secondary battery 11 to the control tower 51 via the first wireless device 41 . Information indicating the temperature of the secondary battery 11 is information indicating the detection value of the temperature detection unit 14 . The vehicle ECU 31 functions as a temperature transmission control section.

In 2nd Embodiment, the control part 52 of the control tower 51 performs the following processes.
As shown in FIG. 5, in step S21, the control unit 52 determines whether there is an automatic guided vehicle 10 whose temperature of the secondary battery 11 is equal to or higher than a threshold. The threshold is a value set so as to prevent the temperature of the secondary battery 11 from becoming higher than the allowable temperature, and is set to a value lower than the upper limit of the allowable temperature of the secondary battery 11 . When there is an automatic guided vehicle 10 whose temperature of the secondary battery 11 is equal to or higher than the threshold value, the control unit 52 performs the process of step S22. On the other hand, when there is no automatic guided vehicle 10 whose temperature of the secondary battery 11 is equal to or higher than the threshold value, the control unit 52 proceeds to step S26.

In step S<b>22 , the control unit 52 calculates the charging time, which is the time required to fully charge the secondary battery 11 of each automatic guided vehicle 10 . In step S22, the charging time required to fully charge the secondary battery 11 when the secondary battery 11 is charged with the maximum charging current that the charger 61 can output is calculated.

Next, in step S23, the control unit 52 calculates the charging time required to fully charge the secondary battery 11 when the charging current is suppressed for the secondary battery 11 whose temperature is equal to or higher than the threshold. The charging current here is a charging current lower than the charging current in step S22 and is a predetermined value.

Next, in step S24, the control unit 52 determines the charging order based on the expected arrival time and the charging times calculated in steps S22 and S23. The control unit 52 determines that the shortest arrival time received by the automatic guided vehicle 10 with the temperature of the secondary battery 11 equal to or higher than the threshold is less than the shortest arrival time received by the automatic guided vehicle 10 with the temperature of the secondary battery 11 less than the threshold. determine the charging order so that the For example, the control unit 52 calculates the charging end time of each automatic guided vehicle 10 from the expected arrival time and the charging time. Assuming that the time between the charging end time and the expected arrival time is the chargeable time, the control unit 52 determines the charging order so that the chargeable time of the secondary battery 11 whose temperature is equal to or higher than the threshold is the longest. By performing the process of step S24, the control unit 52 functions as a charging order determination unit.

Next, in step S<b>25 , the control unit 52 transmits information indicating the charging order determined in step S<b>24 from the second wireless device 55 to each automatic guided vehicle 10 . The vehicle ECU 31 of each automatic guided vehicle 10 acquires information indicating the charging order from the first wireless device 41 . The vehicle ECU 31 of each automatic guided vehicle 10 performs charging by the charger 61 according to the charging order determined by the control tower 51 . The control performed by the vehicle ECU 31 of each automatic guided vehicle 10 during charging of the secondary battery 11 is the same as in the first embodiment. That is, the secondary battery 11 is charged according to the process shown in FIG. By executing the process of step S25, the control unit 52 functions as an order transmission control unit. The information indicating the charging order is, for example, information that instructs each automatic guided vehicle 10 that charging start time=estimated arrival time.

In step S<b>26 , the control unit 52 causes the secondary battery 11 of each automatic guided vehicle 10 to be charged depending on the expected arrival time of each automatic guided vehicle 10 . That is, the control unit 52 does not determine the order of charging, and each automatic guided vehicle 10 charges the secondary batteries 11 in order of earliest expected arrival time.

The operation of the second embodiment will be described.
As shown in FIG. 6, the four automatic guided vehicles 10 are respectively designated as a first automatic guided vehicle 10A, a second automatic guided vehicle 10B, a third automatic guided vehicle 10C, and a fourth automatic guided vehicle 10D. During the operation of each automatic guided vehicle 10, the temperature of the secondary battery 11 of each automatic guided vehicle 10 varies. Variation in the temperature of the secondary battery 11 is caused by Joule heat. The temperature of the secondary battery 11 varies depending on the weight of the load conveyed by each automatic guided vehicle 10 and the travel routes R1, R2, R3. In the example shown in FIG. 6, the temperature of the secondary battery 11 of the second automatic guided vehicle 10B among the four automatic guided vehicles 10 is It is higher than the temperature of the secondary battery 11 and the secondary battery 11 of the fourth automatic guided vehicle 10D. The temperature of the secondary battery 11 of the second automatic guided vehicle 10B is equal to or higher than the threshold. The temperatures of the secondary battery 11 of the first automatic guided vehicle 10A, the secondary battery 11 of the third automatic guided vehicle 10C, and the secondary battery 11 of the fourth automatic guided vehicle 10D are below the threshold.

When information indicating the temperature of the secondary battery 11 is transmitted from each automatic guided vehicle 10 to the control tower 51, the control unit 52 determines the charging order according to the process shown in FIG. In the above example, when charging the secondary battery 11 by the charger 61, the shortest arrival time transmitted to the second automatic guided vehicle 10B is the first automatic guided vehicle 10A, the third automatic guided vehicle 10C, and the fourth automatic guided vehicle 10C. The charging order is transmitted so as to be shorter than the shortest arrival time transmitted to the automatic guided vehicle 10D.

FIG. 7 shows the charging time when the secondary battery 11 of each automatic guided vehicle 10 is charged by the charger 61 . The longer the shortest arrival time, the longer the charging time by the charger 61. Therefore, the time TB during which the secondary battery 11 of the second automatic guided vehicle 10B is charged is the first automatic guided vehicle 10A and the third automatic guided vehicle. It is longer than the times TA, TC, and TD during which the secondary batteries 11 of the 10C and the fourth automatic guided vehicle 10D are charged. The vehicle ECU 31 decreases the command value of the charging current as the shortest arrival time is longer. It is charged with a charging current smaller than that of the secondary battery 11 of the automatic guided vehicle 10D.

FIG. 8 shows the relationship between the charging rate of the secondary battery 11 of the second automatic guided vehicle 10B and the temperature. As shown in FIG. 8, the charging rate of the secondary battery 11 decreases until time T1 as the second automatic guided vehicle 10B travels. When charging of the secondary battery 11 by the charger 61 is started at time T1, the charging rate of the secondary battery 11 increases. At this time, since the charging current is small, the temperature of the secondary battery 11 gradually decreases. In FIG. 8, the temperature of the secondary battery 11 is lower at time T2 when charging ends than at time T1 when charging starts.

Effects of the second embodiment will be described. According to the second embodiment, the following effects can be obtained in addition to the effects of the first embodiment.
(2-1) The control unit 52 of the control tower 51 can recognize the estimated arrival time of each automatic guided vehicle 10 from the information indicating the estimated arrival time transmitted from each automatic guided vehicle 10 . When each automatic guided vehicle 10 charges the secondary battery 11, the control unit 52 determines that the shortest arrival time received by the automatic guided vehicle 10 at which the temperature of the secondary battery 11 is equal to or higher than the threshold is set to The charging order can be determined to be longer than the shortest arrival time received by the AGV 10 whose temperature is below the threshold. In other words, the control unit 52 can determine the charging order so as to secure a long charging time when the secondary battery 11 whose temperature is equal to or higher than the threshold is charged by the charger 61 . The longer the shortest arrival time, the longer the time for charging the secondary battery 11 by the charger 61 can be secured. Since the command value of the charging current becomes smaller as the shortest arrival time becomes longer, it is possible to suppress the temperature rise of the secondary battery 11 whose temperature is equal to or higher than the threshold. Therefore, deterioration of the secondary battery 11 can be suppressed.

When the temperature of only the secondary batteries 11 of some of the automatic guided vehicles 10 rises, the deterioration of the secondary batteries 11 whose temperature rises is accelerated. In this case, the deterioration of some of the secondary batteries 11 in the automatic guided vehicles 10 is promoted, and the lives of the secondary batteries 11 vary among the automatic guided vehicles 10 . For the secondary battery 11 whose temperature reaches or exceeds the threshold value, by suppressing heat generation during charging, it is possible to suppress variation in the life of the secondary battery 11 among the automatic guided vehicles 10 .

Each embodiment can be modified and implemented as follows. Each embodiment and the following modifications can be implemented in combination with each other within a technically consistent range.
O In each embodiment, the expected arrival time may be calculated by the control tower 51 . Since the control unit 52 instructs the automatic guided vehicle 10 on the traveling routes R1, R2, and R3, the traveling routes R1, R2, and R3 of the automatic guided vehicle 10 can be recognized. The control unit 52 stores the correspondence between the travel routes R1, R2, R3 and the travel distances in the storage unit 54, so that the travel routes R1, R2, R3 of the respective automatic guided vehicles 10 can be calculated. Distance traveled can be calculated. The weight of the automatic guided vehicle 10 is a known value, and by storing the weight of the automatic guided vehicle 10 in the storage unit 54 , the control unit 52 can recognize the weight of each automatic guided vehicle 10 . Note that even if a plurality of types of automatic guided vehicles 10 with different weights are used in the container terminal T, the weights and identification information of the automatic guided vehicles 10 are stored in the storage unit 54 in association with each other. Therefore, the control unit 52 can recognize the weight of each automatic guided vehicle 10 . The control unit 52 can recognize the weight average value of the load from the weight of the container C transported by the automatic guided vehicle 10 in the past. Therefore, the control unit 52 can calculate the amount of power consumed by each automatic guided vehicle 10 from the traveling routes R1, R2, R3, the weight of the automatic guided vehicle 10, and the average weight of the load. In this case, the controller 52 functions as a power consumption calculator. Information indicating the travel distances of the travel routes R1, R2, and R3, the weight of the automatic guided vehicle 10, and the weight average value of the load may be transmitted from each automatic guided vehicle 10 to the control tower 51. In this case, the control unit 52 can also calculate power consumption from information acquired via the second wireless device 55 .

The vehicle average efficiency is a preset value, and by storing the vehicle average efficiency in the storage unit 54 , the control unit 52 can recognize the vehicle average efficiency of each automatic guided vehicle 10 . As with the weight of the automatic guided vehicle 10, even if multiple types of automatic guided vehicles 10 are used in the container terminal T, the vehicle average efficiency of the automatic guided vehicle 10 and the identification information are associated with each other. By storing in the storage unit 54 , the control unit 52 can recognize the vehicle average efficiency for each automatic guided vehicle 10 . The control unit 52 acquires information indicating the charging rate of the secondary battery 11 from the second wireless device 55 . Since the control unit 52 cannot estimate the charging rate of the secondary battery 11, it is necessary to use information transmitted from the automatic guided vehicle 10. FIG. Then, the control unit 52 calculates the expected arrival time of each automatic guided vehicle 10 from the vehicle average efficiency, the calculated power consumption, and the charging rate of the secondary battery 11 obtained from the second radio device 55 . In this case, the controller 52 functions as an estimated arrival time calculator. Information indicating the vehicle average efficiency may be transmitted from each automatic guided vehicle 10 to the control tower 51 . The control unit 52 calculates the expected arrival time from the expected arrival time and the current time, and transmits the calculated expected arrival time to each automatic guided vehicle 10 .

As described above, the automatic guided vehicle 10 can cause the control unit 52 to calculate the expected arrival time by transmitting at least the information indicating the charging rate of the secondary battery 11 from the first wireless device 41 . Therefore, the information with which the expected arrival time can be recognized may be information necessary for causing the control unit 52 to derive the expected arrival time. Either the automatic guided vehicle 10 or the control tower 51 constituting the automatic guided vehicle system TS may be provided with the power consumption calculation unit and the estimated arrival time calculation unit.

O In each embodiment, the command value transmitted from the vehicle ECU 31 to the charging control unit 63 may be a command value for charging power. The vehicle ECU 31 decreases the charging power command value as the shortest arrival time is longer. Charger 61 outputs the commanded charging power. The deterioration of the secondary battery 11 is suppressed as the charging power becomes smaller. Therefore, even in this case, effects similar to those of each embodiment can be obtained.

O In each embodiment, the vehicle ECU 31 may transmit information indicating the expected arrival time to the control tower 51 instead of the information indicating the expected arrival time. In this case, the information with which the expected arrival time can be recognized is information indicating the expected arrival time. That is, the information with which the expected arrival time can be recognized may be information indicating the expected arrival time itself. Further, the control tower 51 may transmit information indicating the expected arrival time to each automatic guided vehicle 10 instead of the information indicating the expected arrival time. The vehicle ECU 31 can recognize the shortest expected arrival time of each automatic guided vehicle 10 as the shortest arrival time. Therefore, the information that allows the shortest arrival time to be recognized may be information indicating the expected arrival time of each automatic guided vehicle 10 . That is, if the information transmitted from the vehicle ECU 31 of each automatic guided vehicle 10 to the control tower 51 is information that allows the vehicle ECU 31 of the automatic guided vehicle 10 to be charged by the charger 61 to recognize the shortest arrival time. , any information.

O In each embodiment, the vehicle ECU 31 does not need to acquire the estimated arrival times of all the other automatic guided vehicles 10 in step S11. The vehicle ECU 31 only needs to obtain the expected arrival time of the automatic guided vehicle 10 that reaches the charger 61 earliest among the other automatic guided vehicles 10 . In other words, the control unit 52 may transmit only the information indicating the earliest expected arrival time among the information indicating the expected arrival times acquired from the automatic guided vehicles 10 from the second wireless device 55 . If only the estimated arrival time of the automatic guided vehicle 10 that reaches the charger 61 earliest among the other automatic guided vehicles 10 can be acquired, the shortest arrival time can be derived, so even in this case, the same effect as each embodiment can be obtained. can be obtained.

(circle) in each embodiment, vehicle ECU31 may acquire the information which shows the shortest arrival time by step S11. In this case, the control unit 52 extracts the earliest expected arrival time from the information indicating the expected arrival times acquired from each automatic guided vehicle 10, and derives the shortest arrival time from the difference between the expected arrival time and the current time. The control unit 52 transmits information indicating the shortest arrival time from the second wireless device 55 . In this case, the information with which the shortest arrival time can be recognized is information indicating the shortest arrival time itself.

○ In each embodiment, the vehicle ECU 31 determines the expected arrival time from the relationship between the expected arrival time of the other automatic guided vehicle 10 and the charging rate of the secondary battery 11 of the other automatic guided vehicle 10 in the process after step S11. You may judge the validity of For example, the vehicle ECU 31 may determine that the expected arrival time is not appropriate when the time from the current time to the expected arrival time is short even though the charging rate of the secondary battery 11 is high. If the time from the current time to the expected arrival time is long even though the charging rate of the secondary battery 11 is low, the vehicle ECU 31 may determine that the expected arrival time is inappropriate. Then, the vehicle ECU 31 may not adopt the estimated arrival time determined to be inappropriate as the value used for the control. In this case, the vehicle ECU 31 does not need to acquire the charging rate information of the other automatic guided vehicles 10 in step S11.

o In each embodiment, the number of travel routes R1, R2, and R3 may be different from three. The number of travel routes R1, R2, and R3 may be singular.
(circle) in each embodiment, the number of automatic guided vehicles 10 should just be more than the number of chargers 61, and may be changed suitably.

(circle) in each embodiment, the number of chargers 61 provided in the charging field P2 should just be less than the number of the automatic guided vehicles 10, and may be two or more. When a plurality of chargers 61 are provided, which charger 61 to charge each automatic guided vehicle 10 may be determined by a command from the control tower 51 or may be determined in advance. For each charger 61 , the control tower 51 recognizes the automatic guided vehicle 10 that charges the secondary battery 11 with the charger 61 . The control tower 51 can recognize, for each charger 61, the expected arrival time of the unmanned guided vehicle 10 that reaches the charger 61 earliest = the shortest arrival time for the unmanned guided vehicle 10 connected to the charger 61. Send information.

○ In each embodiment, the charger 61 may charge the secondary battery 11 in a non-contact manner. In this case, the charging current command value may be set by a wireless device that instructs the charger 61 by a wireless signal.

O In each embodiment, the unmanned transport system TS may be used in areas other than the container terminal T as long as it is an area where cargo is transported according to commands from the control tower 51 .
(circle) in each embodiment, the automatic guided vehicle 10 may be equipped with communication ECU for communicating by the 1st radio|wireless machine 41. FIG. In other words, an ECU for controlling traveling and an ECU for controlling communication may be provided separately. Further, in each embodiment, the automatic guided vehicle 10 may include a charging ECU for controlling the charger 61 . That is, an ECU for controlling driving and an ECU for controlling charging may be provided separately.

O In each embodiment, the state of charge of the secondary battery 11 may be the remaining capacity of the secondary battery 11 . The remaining capacity of the secondary battery 11 can be estimated by multiplying the full charge capacity of the secondary battery 11 by the charging rate of the secondary battery 11 . Also, the state of charge of the secondary battery 11 may be the voltage across the terminals of the secondary battery 11 . Since there is a correlation between the charging rate of the secondary battery 11 and the voltage across the terminals of the secondary battery 11 , the voltage across the terminals of the secondary battery 11 can be regarded as the state of charge of the secondary battery 11 .

○ In each embodiment, the command unit, travel control unit, transmission control unit, shortest arrival time acquisition unit, power consumption calculation unit, expected arrival time calculation unit, and temperature transmission control unit are functions of individual control devices. may be provided as

(circle) in 1st Embodiment, the automatic guided vehicle 10 does not need to be equipped with the temperature detection part 14. FIG.
O In the second embodiment, the shortest arrival time transmission control section, the charging order determination section, and the order transmission control section may be provided as functions of individual control devices.

P2... Charging station, R1, R2, R3... Running route, T... Container terminal as a region, TS... Automatic guided vehicle, 10... Automatic guided vehicle, 11... Secondary battery, 14... Temperature detector, 16... For traveling Motor 21 Battery ECU functioning as state-of-charge estimating unit 31 Commanding unit, travel control unit, transmission control unit, shortest arrival time acquisition unit, power consumption calculation unit, expected arrival time calculation unit, temperature transmission control unit Functioning vehicle ECU 41... First radio functioning as a receiving unit and a transmitting unit 51... Control tower as a host system 52... Functioning as a shortest arrival time transmission control unit, a charging order determination unit, and an order transmission control unit 55 .

Claims (3)

An unmanned guided vehicle having more chargers than the chargers in an area comprising a charging field where chargers are arranged and a travel route,
a running motor;
a secondary battery serving as a power source for the running motor;
a state-of-charge estimation unit that estimates the state of charge of the secondary battery;
a command unit that transmits a command value of charging current or charging power to the charger that charges the secondary battery;
a receiver that receives commands from a host system;
a transmission unit that transmits information to the host system;
a travel control unit that causes the unmanned guided vehicle to travel according to the instruction of the travel route from the host system;
a transmission control unit configured to transmit, from the transmission unit to the host system, information enabling recognition of an expected arrival time, which is the time required for the automatic guided vehicle to reach the charger;
The shortest arrival time for acquiring from the receiving unit information enabling recognition of the shortest arrival time, which is the shortest of the expected arrival times of other automated guided vehicles, when charging the secondary battery by the charger. an acquisition unit;
A power consumption calculation unit that calculates the power consumption of the secondary battery from the travel route, the weight of the automatic guided vehicle, and the average weight of the load conveyed by the automatic guided vehicle;
calculating the estimated time of arrival from the power consumption calculated by the power consumption calculating unit, the state of charge estimated by the state of charge estimating unit, and vehicle average efficiency in consideration of loss caused by the automatic guided vehicle; and an expected arrival time calculation unit,
The command unit reduces the command value as the shortest arrival time increases. an unmanned guided vehicle having more chargers than the chargers in an area including a charging station where the chargers are arranged and a travel route;
An automated guided vehicle system comprising a host system that transmits commands to the automated guided vehicle,
The automatic guided vehicle,
a running motor;
a secondary battery serving as a power source for the running motor;
a state-of-charge estimation unit that estimates the state of charge of the secondary battery;
a command unit that transmits a command value of charging current or charging power to the charger that charges the secondary battery;
a receiving unit that receives a command from the host system;
a transmission unit that transmits information to the host system;
a travel control unit that causes the unmanned guided vehicle to travel according to the instruction of the travel route from the host system;
a transmission control unit configured to transmit, from the transmission unit to the host system, information enabling recognition of an expected arrival time, which is the time required for the automatic guided vehicle to reach the charger;
The shortest arrival time for acquiring from the receiving unit information enabling recognition of the shortest arrival time, which is the shortest of the expected arrival times of other automated guided vehicles, when charging the secondary battery by the charger. an acquisition unit;
The command unit decreases the command value as the shortest arrival time increases,
The upper system is
a command transmission unit that transmits the command to the automatic guided vehicle;
an information receiving unit that receives the information transmitted from the transmitting unit;
a shortest arrival time transmission control unit that transmits information that allows the shortest arrival time to be recognized from the command transmission unit to the automatic guided vehicle;
The unmanned carrier system
A power consumption calculation unit that calculates the power consumption of the secondary battery from the travel route, the weight of the automatic guided vehicle, and the average weight of the load conveyed by the automatic guided vehicle;
calculating the estimated time of arrival from the power consumption calculated by the power consumption calculating unit, the state of charge estimated by the state of charge estimating unit, and vehicle average efficiency in consideration of loss caused by the automatic guided vehicle; An unmanned guided vehicle system comprising: an estimated arrival time calculation unit. The automatic guided vehicle,
a temperature detection unit that detects the temperature of the secondary battery;
a temperature transmission control unit that transmits information indicating the temperature of the secondary battery from the transmission unit to the host system;
The upper system is
The shortest arrival time received by the automatic guided vehicle in which the temperature of the secondary battery is equal to or higher than a threshold is longer than the shortest arrival time received by the automatic guided vehicle in which the temperature of the secondary battery is less than the threshold. a charging order determining unit that determines the charging order as follows;
By transmitting the charging order determined by the charging order determining unit from the command transmitting unit to the automatic guided vehicle, the automatic guided vehicle is caused to charge the secondary batteries in the order determined by the charging order. 3. The automatic guided vehicle system according to claim 2 , further comprising an order transmission control section.

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