JP6831665B2 - Communication systems, vehicles and computer programs - Google Patents

Description

The present invention relates to a communication system in which communication is performed between a plurality of transport vehicles, a transport vehicle included in the communication system, and a computer program for causing a computer to control the operation of the transport vehicle.

As one of the factories that produce products, there is a factory in which a plurality of transport vehicles automatically transport workpieces such as welded parts, electronic parts, substrates, and wafers. As a matter of course, each of these transport vehicles needs to transport the work while avoiding contact with other transport vehicles. As a configuration for avoiding contact between the two transport vehicles, a configuration in which a plurality of transport vehicles communicate with each other wirelessly can be considered.

Patent Document 1 discloses a configuration in which a plurality of vehicles communicate with each other. In this configuration, each of the plurality of vehicles receives data indicating the position of another vehicle, and displays the position indicated by the received data together with the map.

JP-A-2007-94698

In a communication system in which a plurality of transport vehicles communicate with each other, each of the plurality of transport vehicles identifies another vehicle that may come into contact with the own vehicle, and makes adjustments related to traveling with the identified other vehicle. At this time, it is necessary for each of the plurality of transport vehicles to appropriately specify the target for adjusting the traveling. For example, even when the two transport vehicles are close to each other, when the two transport vehicles are moving in a direction away from each other, one transport vehicle adjusts the other transport vehicle for traveling. It is not necessary to specify as the target to perform.

The present invention has been made in view of such circumstances, and an object of the present invention is to provide a communication system, a transport vehicle, and a computer program capable of appropriately specifying a target for adjustment regarding traveling. ..

The communication system according to the present invention is fixed at a predetermined indoor position, has a plurality of transmitting stations for transmitting radio signals, a plurality of transport vehicles traveling in the room, and is installed in the room and is wireless. and a reflector for reflecting the radio signal to the between the two shield for shielding signals, said plurality of transport pullers s includes a signal receiving unit that receives a radio signal of the plurality of transmission station transmitted, the Among the radio signals received by the signal receiving unit, a position calculation unit that calculates the position of the own vehicle based on the propagation distances of a plurality of radio signals whose sources are different from each other, and a position calculation unit calculated by the position calculation unit. A determination unit that determines the planned travel route to be traveled, a data transmission unit that wirelessly transmits travel data indicating the planned travel route determined by the determination unit to another transport vehicle, and another transport. A data receiving unit that receives the traveling data from the vehicle, an adjustment determination unit that determines whether or not adjustments should be made to the source of the traveling data and driving based on the traveling data received by the data receiving unit . a plurality of radio signals corresponding to each of the plurality of the propagation distances husband used in the calculation of the position calculating section, possess a determining signal determining unit whether contains radio signal reflected by the reflector, the position The calculation unit is characterized in that when it is determined by the signal determination unit that the radio signal reflected by the reflector is included, the position of the own vehicle is calculated based on the related information related to the own vehicle. ..

In the present invention, when each of the plurality of transport vehicles receives the travel data, it is determined whether or not the transmission of the travel data and the travel adjustment should be made based on the travel schedule route indicated by the received travel data. judge. Therefore, each of the plurality of transport vehicles can appropriately identify an object for which the traveling adjustment is made, for example, another transport vehicle that is likely to come into contact with the own vehicle.

In addition , reflectors that reflect radio signals transmitted by a plurality of transmitting stations are installed in the room. Therefore, the range in which the transport vehicle can receive the wireless signal is wide in the room. The reflector reflects the radio signal towards the two shields.
The propagation distance of the radio signal transmitted from one transmitting station, reflected by the reflector and reaching the carrier is longer than the propagation distance of the radio signal directly from the same transmitting station to the same carrier. Therefore, when the plurality of radio signals corresponding to the plurality of propagation distances used in the position calculation include the radio signal reflected by the reflector, the accurate position is not calculated. Therefore, when it is determined that the plurality of radio signals corresponding to the plurality of propagation distances used in the calculation of the position of the own vehicle include the radio signal reflected by the reflector, the plurality of transport vehicles themselves The position of the own vehicle is calculated based on the related information related to the vehicle, for example, the information indicating the traveling direction and the speed of the own vehicle. As a result, each of the plurality of transport vehicles appropriately calculates the position of its own vehicle.
The communication system according to the present invention is characterized in that the related information indicates whether or not the transport vehicle is close to the reflector.
In the present invention, each of the plurality of transport vehicles calculates the position of the own vehicle based on the information indicating whether or not the transport vehicle (own vehicle) is close to the reflector.

The communication system according to the present invention is characterized in that the adjustment related to the traveling is performed by changing at least one of the planned traveling route and the traveling speed.

In the present invention, each of the plurality of transport vehicles changes at least one of the planned travel route and the travel speed when it is determined that the transmission of the travel data and the adjustment regarding the travel should be performed. As a result, contact between the two transport vehicles is avoided.

In the communication system according to the present invention, the travel data further indicates the priority of travel with respect to the source of the travel data, and the plurality of transport vehicles each determine that the adjustment determination unit should make adjustments related to the travel. In that case, the target determination unit that determines whether or not the own vehicle should make adjustments related to the own vehicle based on the priority of the traveling related to the own vehicle and the priority indicated by the traveling data received by the data receiving unit. It is characterized by having.

In the present invention, when it is determined that each of the plurality of transport vehicles should make adjustments regarding the transmission of the travel data and the travel, the travel priority regarding the own vehicle is higher than the travel priority regarding the transmission source. When it is low, it is judged that the own vehicle should make adjustments related to running. In the same case, each of the plurality of transport vehicles determines that the own vehicle should not make adjustments regarding the running when the running priority regarding the own vehicle is higher than the running priority regarding the transmission source.

In the communication system according to the present invention, the travel data further indicates at least one index in the vehicle height, vehicle width, and weight of the source of the travel data, and the plurality of transport vehicles are each subjected to the adjustment determination unit. When it is determined that the adjustment related to the traveling should be performed, whether or not the own vehicle should make the adjustment related to the traveling based on the index of the own vehicle and the index indicated by the traveling data received by the data receiving unit. It is characterized by having a target determination unit for determination.

In the present invention, when it is determined that each of the plurality of transport vehicles should make adjustments regarding the transmission of the travel data and the travel, the vehicle is related to the travel based on the index of the own vehicle and the transmission source of the travel data. Determine if the vehicle should make the adjustment. For example, when it is determined that the transmission and the traveling adjustment should be made, each of the plurality of transport vehicles determines that the traveling adjustment should be made when the weight of the own vehicle is lighter than the weight of the transmission source. ..

The transport vehicle according to the present invention is a transport vehicle that travels in a room in which a reflector that reflects radio signals toward two shields that shield radio signals is installed, and receives signals that receive radio signals. A position calculation unit that calculates the position of the own vehicle based on the propagation distances of a plurality of wireless signals whose sources are different from each other among the radio signals received by the unit and the signal reception unit, and the position calculation unit calculates the position. A determination unit that determines a planned travel route based on the determined position, a data transmission unit that wirelessly transmits travel data indicating the travel schedule route determined by the determination unit, and the travel data. Based on the data receiving unit to receive, the adjustment determination unit that determines whether or not to make adjustments related to the source of the traveling data and the traveling based on the traveling data received by the data receiving unit, and the calculation of the position calculation unit. The position calculation unit includes a signal determination unit that determines whether or not the radio signal reflected by the reflector is included in the plurality of radio signals corresponding to each of the plurality of propagation distances to be used. When it is determined that the radio signal reflected by the reflector is included, the position of the own vehicle is calculated based on the related information related to the own vehicle .

In the present invention, when the travel data is received, it is determined whether or not the transmission of the travel data and the adjustment regarding the travel should be performed based on the travel schedule route indicated by the received travel data. Therefore, it is possible to appropriately specify the target for adjusting the running.
In addition, reflectors that reflect radio signals transmitted by a plurality of transmitting stations are installed in the room. Therefore, the range in which the transport vehicle can receive the wireless signal is wide in the room. The reflector reflects the radio signal towards the two shields.

The computer program according to the present invention operates the transport vehicle on a computer mounted on a transport vehicle traveling in a room in which a reflector that reflects the radio signal toward two shields that shield the radio signal is installed. a computer program for controlling, calculates the position of the guided vehicle based on the propagation distance of the different radio signals to each other source, corresponding to each of the plurality of the propagation distances husband used in the calculation of the position of the transport vehicle It is determined whether or not the radio signals reflected by the reflector are included in the plurality of radio signals, and if it is determined that the radio signals reflected by the reflector are included, it is related to the transport vehicle. The position of the transport vehicle is calculated based on the related information to be performed, the planned travel route on which the transport vehicle is scheduled to travel is determined based on the calculated position of the transport vehicle, and the determined travel schedule route is shown. Instructing the wireless transmission of travel data including route data, acquiring the wirelessly received travel data, and based on the acquired travel data, the carrier vehicle adjusts the source of the travel data and travel. It is characterized in that a computer is made to execute a process of determining whether or not to perform.

In the present invention, when the computer mounted on the transport vehicle acquires the travel data, the transport vehicle mounted on the transport vehicle transmits the travel data based on the planned travel route indicated by the acquired travel data. Determine if adjustments should be made between the original and the run. Therefore, the computer can appropriately identify the target to be adjusted for traveling.
In addition, reflectors that reflect radio signals transmitted by a plurality of transmitting stations are installed in the room. Therefore, the range in which the transport vehicle can receive the wireless signal is wide in the room. The reflector reflects the radio signal towards the two shields.

According to the present invention, it is possible to appropriately specify the target to be adjusted for traveling.

It is a block diagram which shows the main part structure of the communication system in Embodiment 1. FIG. It is a block diagram which shows the composition of the main part of a transmitting station. It is explanatory drawing of the method of generating a radio signal. It is a block diagram which shows the composition of the main part of a transport vehicle. It is a block diagram which shows the main part structure of the position arithmetic unit. It is explanatory drawing of decoding to the baseband signal. It is a flowchart which shows the procedure of the position calculation processing. It is a flowchart which shows the procedure of the position calculation processing. It is a chart which shows the correlation value and propagation distance associated with a signal source. It is a block diagram which shows the main part structure of a travel control device. It is a flowchart which shows the procedure of a transmission process. It is a flowchart which shows the procedure of the 1st adjustment process. It is a flowchart which shows the procedure of the 2nd adjustment process.

Hereinafter, the present invention will be described in detail with reference to the drawings showing the embodiments thereof.
(Embodiment 1)
FIG. 1 is a block diagram showing a main configuration of the communication system 1 according to the first embodiment. The communication system 1 is provided in the room R and includes three transmission stations 10a, 10b, 10c, a control device 11, three transport vehicles 12a, 12b, 12c, and a reflector 13. The transmitting stations 10a, 10b, and 10c are fixed at predetermined positions of the room R, respectively. The positions of the transmitting stations 10a, 10b, and 10c are the corners of the room R and are different from each other. The transmitting stations 10a, 10b, and 10c are connected to the control device 11 by wire.

The transport vehicles 12a, 12b, and 12c each transport a workpiece such as a welded part, an electronic part, a substrate, or a wafer. A triangular columnar reflector 13 is installed in the room R. Further, the shields O1 and O2 are present in the room R. The transport vehicles 12a, 12b, and 12c each travel in the indoor R while avoiding contact with the reflector 13 and the shields O1 and O2.

The transmitting stations 10a, 10b, and 10c each transmit radio signals to the transport vehicles 12a, 12b, and 12c according to the instructions of the control device 11. The reflector 13 reflects the radio signal transmitted by the transmitting stations 10a, 10b, and 10c. Shields O1 and O2 each shield the radio signal. Shields O1 and O2 are juxtaposed. The radio signals transmitted from the transmission stations 10b and 10c are reflected by the reflector 13 and propagate between the shields O1 and O2 as indicated by the broken line arrows.

Each of the transport vehicles 12a, 12b, and 12c calculates the position of its own vehicle based on the radio signals received from the transmission stations 10a, 10b, and 10c, and based on the calculated position, the planned travel route on which the vehicle is scheduled to travel. Is determined, and the vehicle travels on the determined travel route. Examples of planned travel routes for the transport vehicles 12a, 12b, and 12c are indicated by solid arrows.

For example, the transport vehicles 12a, 12b, and 12c each cycle in turn in a plurality of preset set positions in the indoor R. The transport vehicles 12a, 12b, and 12c determine, for example, a planned travel route to a set position to be currently headed based on the calculated position.

The transport vehicles 12a, 12b, and 12c each wirelessly transmit data to other transport vehicles and receive data wirelessly from the other transport vehicles. Each of the transport vehicles 12a, 12b, and 12c avoids contact with the other transport vehicle by adjusting the traveling with the other transport vehicle. The frequency band used when each of the transport vehicles 12a, 12b, 12c transmits data to another transport vehicle is different from the frequency band of the radio signal transmitted by the transmission stations 10a, 10b, 10c.

In the following, the source of the radio signal will be described as the signal source, and the source of the data will be described as the data source. The signal transmission source is one of the transmission stations 10a, 10b, 10c, and the data transmission source is one of the transport vehicles 12a, 12b, 12c.

FIG. 2 is a block diagram showing a main configuration of the transmitting station 10a. The transmission station 10a includes a signal output unit 20, a clock unit 21, a coding unit 22, a code signal generator 23, a superimposition unit 24, a carrier wave generator 25, an amplifier 26, and a transmission antenna 27.

The signal output unit 20 acquires time information indicating the current time from the clock unit 21. When the signal output unit 20 acquires the time information from the clock unit 21, the time indicated by the time information acquired by the signal output unit 20 coincides with or substantially matches the time at the time of acquisition. Further, the signal output unit 20 receives an instruction to transmit a wireless signal from the control device 11. The signal output unit 20 acquires time information from the clock unit 21 when a transmission instruction is input. The signal output unit 20 outputs a baseband signal including time information acquired from the clock unit 21, source information indicating the transmission station 10a, coordinate information indicating the position of the transmission station 10a in coordinates, and the like to the coding unit 22. To do. A stop instruction for instructing the stop of transmission of the wireless signal is input to the signal output unit 20. The signal output unit 20 stops the output of the baseband signal when the stop instruction is input.
The time information included in the baseband signal is transmission time information indicating the transmission time. In the following, the time information included in the baseband signal will be referred to as transmission time information.

The code signal generator 23 outputs a transmission side code signal corresponding to a predetermined code to the coding unit 22. The coding unit 22 encodes the baseband signal by spreading the spectrum of the baseband signal input from the signal output unit 20 by using the transmitting side code signal input from the code signal generator 23. .. The coding unit 22 outputs the coded coded signal to the superimposing unit 24.

The carrier wave generator 25 outputs the carrier wave to the superimposing unit 24. The carrier wave output by the carrier wave generator 25 is a high frequency wave, for example, millimeter wave. The frequency range of millimeter waves is 30 GHz to 300 GHz.
The superimposition unit 24 generates a superimposition signal by superimposing the coded signal input from the coding unit 22 on the carrier wave input from the carrier wave generator 25. The superimposition unit 24 outputs the generated superimposition signal to the amplifier 26.

The amplifier 26 amplifies the amplitude of the superposed signal input from the superimposing unit 24, and outputs the superposed signal with the amplified amplitude to the transmitting antenna 27. The transmitting antenna 27 transmits the superimposed signal input from the amplifier 26 as a wireless signal to the transport vehicles 12a, 12b, and 12c.

The transmitting antenna 27 has directivity, and as shown in FIG. 1, transmits the radio signal A1 in the first direction, transmits the radio signal A2 in the second direction, and transmits the radio signal A3 in the third direction. .. The transmitting antenna 27 switches the transmitting direction of the radio signal between the first direction, the second direction, and the third direction each time a predetermined time elapses. The transmission direction of the transmission antenna 27 is switched in the order of the first direction, the second direction, and the third direction.
The transmission direction may be switched based on the time indicated by the clock unit 21, a timer (not shown), or an instruction of the control device 11.

When a transmission instruction is input from the control device 11, the signal output unit 20 continuously outputs a baseband signal to the coding unit 22. At this time, the signal output unit 20 outputs the baseband signal to the coding unit 22 each time a predetermined time elapses. Therefore, the transmitting antenna 27 continuously transmits the radio signal, and the transmitting directions of the three radio signals continuously transmitted by the transmitting antenna 27 are different from each other.

FIG. 3 is an explanatory diagram of a method for generating a radio signal. FIG. 3 shows an example of waveforms of a baseband signal, a transmitting side code signal, a coded signal, a carrier wave, and a radio signal. Voltage and time are shown on each of these vertical and horizontal axes. For the sake of brevity, it is assumed that the baseband signal, the transmitting side code signal, and the coded signal are digital signals indicating "+1" or "-1", respectively. In reality, "+1" corresponds to "(amplitude) / 2" and "-1" corresponds to "-(amplitude) / 2".

As described above, the signal output unit 20 outputs a baseband signal including transmission time information, transmission source information, and coordinate information to the coding unit 22. The baseband signal is an NRZ (Non-Return to Zero) signal. As described above, the code signal generator 23 outputs the transmission side code signal to the coding unit 22.

The transmitting side code signal is a signal in which a predetermined waveform determined based on the code is periodically repeated. The code is a list of numbers represented by "0" or "1", and the number of these numbers is the code length. The predetermined waveform determined based on the code is, for example, a waveform in which "0" of the code corresponds to "+1" and "1" of the code corresponds to "-1". In the example of FIG. 3, a predetermined waveform corresponding to the reference numeral “0100101” is repeated. The period T of the transmission-side code signal matches or substantially matches the length of one bit of the baseband signal.

The coding unit 22 encodes the baseband signal by multiplying the baseband signal and the transmitting side code signal. Therefore, the waveform of the encoded signal during the period when the baseband signal indicates "+1" matches the predetermined waveform, and the waveform of the encoded signal during the period when the baseband signal indicates "-1" is positive or negative of the predetermined waveform. Matches the inverted waveform.

The minimum value of the pulse width of the coded signal is smaller than the minimum value of the pulse width of the baseband signal, that is, the period of one bit of the baseband signal. For binary signals, the spectral width is inversely proportional to the minimum pulse width. Therefore, the spectrum of the baseband signal is diffused by the coding unit 22 performing the coding. The minimum value of the pulse width of the coded signal is (minimum value of the pulse width of the baseband signal) / (code length). Therefore, the spectral width of the coded signal is represented by the product of the spectral width of the baseband signal and the code length. In the example of FIG. 3, since the code length is 7, the spectral width of the baseband signal is spread 7 times.

The carrier wave output by the carrier wave generator 25 is a sine wave as shown in FIG. When the carrier wave is millimeter wave, the frequency of the carrier wave is one frequency in 30 GHz to 300 GHz.

As described above, the superimposition unit 24 generates a superimposition signal transmitted as a radio signal from the transmission antenna 27 by superimposing the coded signal output by the coding unit 22 on the carrier wave output by the carrier wave generator 25. To do. The waveform of the superimposed signal during the period when the coded signal indicates "+1" matches the waveform of the carrier wave, and the waveform of the superimposed signal during the period when the coded signal indicates "-1" is a waveform obtained by inverting the positive and negative of the waveform of the carrier wave. Matches.
As described above, the amplitude of the superposed signal generated by the superimposing unit 24 is amplified by the amplifier 26, and the superposed signal whose amplitude is amplified is transmitted from the transmitting antenna 27 as a radio signal.

Each of the transmitting stations 10b and 10c is configured in the same manner as the transmitting station 10a. In the description of the configuration of the transmission station 10a, the configuration of the transmission station 10b can be described by replacing each of the radio signals A1, A2, and A3 with the radio signals B1, B2, and B3. Similarly, in the description of the configuration of the transmission station 10a, the configuration of the transmission station 10c can be described by replacing each of the radio signals A1, A2, and A3 with the radio signals C1, C2, and C3.

The frequencies of the carrier waves output by the carrier wave generators 25 of the transmitting stations 10a, 10b, and 10c are the same or substantially the same. Further, the codes used in the code signal generators 23 of the transmitting stations 10a, 10b, and 10c are the same. Further, the times indicated by the clock units 21 of the transmitting stations 10a, 10b, and 10c are the same or substantially the same. The control device 11 repeatedly adjusts these times so that the times indicated by the clock units 21 of the transmitting stations 10a, 10b, and 10c match.

The control device 11 gives a transmission instruction to the transmission stations 10a, 10b, 10c so that at least two transmission antennas 27 in the three transmission stations 10a, 10b, 10c do not transmit radio signals in the same time zone. The transmitting antenna 27 that outputs and transmits the radio signal is changed over time. Therefore, at all times of the day, only one transmitting station among the transmitting stations 10a, 10b, 10c is transmitting the radio signal, or all of the transmitting stations 10a, 10b, 10c are transmitting the radio signal. Is stopped.

The transmitting antennas 27 of the three transmitting stations 10a, 10b, and 10c transmit radio signals as follows, for example.
First, the control device 11 outputs a transmission instruction to the signal output unit 20 of the transmission station 10a, and changes the transmission antenna for transmitting the radio signal to the transmission antenna 27 of the transmission station 10a. The transmitting antenna 27 of the transmitting station 10a transmits the radio signals A1, A2, and A3 in this order.

After the radio signal A3 is transmitted, the control device 11 outputs a stop instruction to the signal output unit 20 of the transmission station 10a. After that, the control device 11 outputs a transmission instruction to the signal output unit 20 of the transmission station 10b, and changes the transmission antenna for transmitting the radio signal to the transmission antenna 27 of the transmission station 10b. The transmitting antenna 27 of the transmitting station 10b transmits the radio signals B1, B2, and B3 in this order.

After the radio signal B3 is transmitted, the control device 11 outputs a stop instruction to the signal output unit 20 of the transmission station 10b. After that, the control device 11 outputs a transmission instruction to the signal output unit 20 of the transmission station 10c, and changes the transmission antenna for transmitting the radio signal to the transmission antenna 27 of the transmission station 10c. The transmitting antenna 27 of the transmitting station 10c transmits the radio signals C1, C2, and C3 in this order.
After the radio signal C3 is transmitted, the control device 11 outputs a stop instruction to the signal output unit 20 of the transmitting station 10c. After that, the control device 11 outputs the transmission instruction again to the signal output unit 20 of the transmission station 10a.

The signal output units 20 of the transmission stations 10a, 10b, and 10c each stop the output of the baseband signal when three times the predetermined time described above has elapsed after the transmission instruction is input from the control device 11. It may be configured as follows. In this case, the control device 11 may output a transmission instruction each time three times a predetermined time elapses. At this time, the control device 11 outputs transmission instructions in the order of the signal output units 20 of the transmission stations 10a, 10b, and 10c.

FIG. 4 is a block diagram showing a main configuration of the transport vehicle 12a. The transport vehicle 12a has a position calculation device 30 and a travel control device 31. The position calculation device 30 is connected to the travel control device 31.

The position calculation device 30 calculates the position of the transport vehicle 12a based on the radio signals received from the three transmission stations 10a, 10b, and 10c, and transmits the calculated position data indicating the position of the transport vehicle 12a to the travel control device 31. Output.
The travel control device 31 outputs signals to a plurality of in-vehicle devices (not shown) included in the transport vehicle 12a to control the travel of the transport vehicle 12a. The travel control device 31 determines a travel schedule route, for example, a travel schedule route to a set position to which the transport vehicle 12a should currently head, based on the position of the transport vehicle 12a indicated by the position data input from the position calculation device 30. The transport vehicle 12a is made to travel on the determined travel route.

Each of the transport vehicles 12b and 12c is configured in the same manner as the transport vehicle 12a. In the description of the configuration of the transport vehicle 12a, the configuration of the transport vehicle 12b can be described by replacing the transport vehicle 12a with the transport vehicle 12b. Similarly, in the description of the configuration of the transport vehicle 12a, the configuration of the transport vehicle 12c can be described by replacing the transport vehicle 12a with the transport vehicle 12c.

FIG. 5 is a block diagram showing a main configuration of the position arithmetic unit 30.
Hereinafter, the configuration of the position calculation device 30 of the transport vehicle 12a will be described. The position calculation device 30 of each of the transport vehicles 12b and 12c is configured in the same manner as the position calculation device 30 of the transport vehicle 12a. In the description of the configuration of the position calculation device 30 of the transport vehicle 12a, the configuration of the position calculation device 30 of the transport vehicle 12b can be described by replacing the transport vehicle 12a with the transport vehicle 12b. Similarly, in the description of the configuration of the position calculation device 30 of the transport vehicle 12a, the configuration of the position calculation device 30 of the transport vehicle 12c can be described by replacing the transport vehicle 12a with the transport vehicle 12c.

The position arithmetic unit 30 includes a receiving antenna 40, an amplifier 41, a mixer 42, a Doppler measuring instrument 43, an oscillator 44, a low-pass filter (hereinafter referred to as LPF) 45, a decoding unit 46, a receiving detection unit 47, and a code signal generator 48. It has a calculation unit 49, a clock unit 50, a timer 51, an output unit 52, and a storage unit 53.

The receiving antenna 40 receives the radio signal transmitted by the transmitting antenna 27 of the transmitting stations 10a, 10b, and 10c, and outputs the received radio signal to the amplifier 41. The reception band of the radio signal of the reception antenna 40 is a part or the whole of a high frequency band, for example, a frequency band corresponding to millimeter waves (30 GHz to 300 GHz). The receiving antenna 40 functions as a signal receiving unit.
The amplifier 41 amplifies the amplitude of the radio signal received from the receiving antenna 40, and outputs the amplified radio signal to the mixer 42 and the Doppler measuring instrument 43.
The oscillator 44 outputs a sine wave to the mixer 42.

The mixer 42 generates a mixed signal including a coded signal by mixing the radio signal input from the amplifier 41 and the sine wave output from the oscillator 44. The frequency of the sine wave output by the oscillator 44 is, for example, the same as the frequency of the carrier wave of the radio signal received by the receiving antenna 40. The mixer 42 outputs the generated mixed signal to the LPF 45.
The LPF 45 extracts a coded signal from the mixed signal input from the mixer 42, and outputs the extracted coded signal to the decoding unit 46 and the reception detection unit 47.

The code signal generator 48 outputs a receiving side code signal corresponding to a predetermined code to the decoding unit 46. The code used in the code signal generator 48 is the same as the code used in the code signal generator 23 of the transmitting stations 10a, 10b, and 10c. The receiving-side code signal is a signal in which a predetermined waveform determined based on the code is periodically repeated, similarly to the transmitting-side code signal. The predetermined waveform and period are the same for each of the receiving side code signal and the transmitting side code signal.
The code used in the code signal generators 23 and 48 is, for example, a PN (Pseudo Noise) code.

The decoding unit 46 multiplies the receiving side code signal and the coded signal in a state where the receiving side code signal input from the code signal generator 48 and the coded signal input from the LPF 45 are in phase with each other. As a result, the spectrum of the coded signal input from the LPF 45 is depopulated. As a result, the coded signal extracted by the LPF 45 is decoded into a baseband signal.

FIG. 6 is an explanatory diagram of decoding to a baseband signal. In the following, the signal obtained by multiplying the receiving side coded signal and the coded signal will be referred to as a multiplication signal. FIG. 6 shows an example of waveforms of the coded signal, the receiving side coded signal, and the multiplication signal. Voltage and time are shown on each of these vertical and horizontal axes. For simplicity of explanation, it is assumed that the receiving side code signal, the receiving side code signal, and the multiplication signal are digital signals indicating "+1" or "-1", respectively. In reality, "+1" corresponds to "(amplitude) / 2" and "-1" corresponds to "-(amplitude) / 2".

The decoding unit 35 multiplies the coded signal and the receiving side coded signal. Therefore, while the coded signal and the receiving side coded signal both show "+1" or "-1", the multiplication signal shows "+1". Further, among the coded signal and the receiving side coded signal, one of them shows "+1" and the other shows "-1", and the multiplication signal shows "-1".

As shown in FIG. 6, when the phase difference between the coded signal and the receiving side coded signal is not zero, the multiplication signal does not match the baseband signal. At this time, the absolute value of the integrated value calculated by integrating over the period T of the receiving side code signal, that is, the correlation value is small. In the example of FIG. 6, the correlation value is 1.
When the phase difference between the coded signal and the receiving side code is zero, the multiplication signal matches the baseband signal and the correlation value is maximum. In the example of FIG. 6, the maximum value of the correlation value coincides with the length of the period T.

The decoding unit 46 adjusts the phase difference between the coded signal and the receiving side code to zero while monitoring the correlation value. When the correlation value is maximum, the phase difference is zero. As described above, the minimum value of the pulse width of the coded signal is smaller than the minimum value of the pulse width of the baseband signal, and the spectrum width is inversely proportional to the minimum value of the pulse width. Therefore, when the decoding unit 46 performs decoding, the spectrum of the coded signal is despread. Since the minimum value of the pulse width of the baseband signal is expressed by the product of the minimum value of the pulse width of the coded signal and the code length, the spectrum width of the baseband signal is the code length of the spectrum width of the coded signal. It is a value calculated by dividing by. In the example of FIG. 6, since the code length is 7, the spectral width of the coded signal is back-spread by (1/7) times.

The correlation value increases as the reception strength of the radio signal received by the receiving antenna 40 increases. The decoding unit 46 outputs the decoded baseband signal and the correlation value information indicating the correlation value when the phase difference is zero to the calculation unit 49.
When the code used by the code signal generators 23 of the transmitting stations 10a, 10b, and 10c is different from the code used by the code signal generator 48 of the position calculation device 30, the correlation value is small regardless of the phase difference, and the code is encoded. The signal is not decoded into a baseband signal.

As described above, the Doppler measuring instrument 43 shown in FIG. 5 receives a radio signal whose amplitude is amplified from the amplifier 41. When the receiving antenna 40 of the position calculation device 30 of the transport vehicle 12a receives the radio signal while the transport vehicle 12a is moving, the radio signal transmits the frequency of the carrier wave of the radio signal received by the receiving antenna 40. It is different from the carrier frequency of the radio signal at that time. This phenomenon is the so-called Doppler effect.

When the traveling direction of the transport vehicle 12a is the same as the propagation direction of the radio signal, the frequency of the carrier wave of the radio signal received by the receiving antenna 40 is lower than the frequency of the carrier wave at the time of transmission, and the transport vehicle 12a travels. The faster the speed, the greater the difference between these frequencies.
Further, when the traveling direction of the transport vehicle 12a is opposite to the propagation direction of the radio signal, the frequency of the carrier wave of the radio signal received by the receiving antenna 40 is higher than the frequency of the carrier wave at the time of transmission, and the transport vehicle 12a travels. The faster the speed, the greater the difference between these frequencies.

As shown in FIG. 1, when the transport vehicle 12a is located in the region between the two shields O1 and O2 (hereinafter referred to as the shield region), the traveling direction of the transport vehicle 12a is the radio reflected by the reflector 13. The direction is the same as the propagation direction of the signal, or the direction is opposite to the propagation direction of the radio signal reflected by the reflector 13.

From the above, when the carrier 12a is located in the shielded area, the frequency of the carrier wave of the radio signal received by the receiving antenna 40 and the frequency of the carrier wave output by the carrier wave generator 25 of the transmitting stations 10a, 10b, 10c. Based on the difference between the two, the traveling direction of the transport vehicle 12a and the traveling speed of the transport vehicle 12a can be detected.

When the transport vehicle 12a is located in the shielded region, the Doppler measuring instrument 43 of the transport vehicle 12a is based on the difference between the carrier frequency of the radio signal input from the amplifier 41 and a predetermined frequency. The traveling direction and the traveling speed of the transport vehicle 12a are detected. The predetermined frequency is the frequency of the carrier wave output by the carrier wave generator 25 of each of the transmitting stations 10a, 10b, and 10c.

The Doppler measuring instrument 43 outputs vehicle information indicating the detected traveling direction and speed to the calculation unit 49. The vehicle information indicates that the vehicle is approaching the reflector 13 or is moving away from the reflector 13 as the traveling direction.

When the coded signal is input from the LPF 45, the reception detection unit 47 detects the reception of the radio signal and notifies the calculation unit 49 that the reception antenna 40 has received the radio signal.

The calculation unit 49 acquires time information indicating the current time from the clock unit 50. When the calculation unit 49 acquires the time information from the clock unit 50, the time indicated by the time information acquired by the calculation unit 49 substantially coincides with the time at the time of acquisition.
The timer 51 starts and ends timing according to the instruction of the calculation unit 49. The time counting time measured by the timer 51 is read out by the calculation unit 49.
The output unit 52 outputs position data indicating the position of the transport vehicle 12a to the travel control device 31 according to the instruction of the calculation unit 49.

The storage unit 53 is, for example, a non-volatile memory. The computer program P1 is stored in the storage unit 53. Various data are stored in the storage unit 53 by the calculation unit 49. Further, the data stored in the storage unit 53 is read out by the calculation unit 49.
The calculation unit 49 has a CPU (Central Processing Unit) (not shown), and the CPU of the calculation unit 49 executes a position calculation process for calculating the position of the carrier 12a by executing the computer program P1.

The computer program P1 may be stored in the storage medium E1 so that the computer can read it. In this case, the computer program P1 read from the storage medium E1 by a reading device (not shown) is stored in the storage unit 53. The storage medium E1 is an optical disk, a flexible disk, a magnetic disk, a magnetic disk disk, a semiconductor memory, or the like. The optical disk is a CD (Compact Disc) -ROM (Read Only Memory), a DVD (Digital Versatile Disc) -ROM, or a BD (Blu-Ray (registered trademark) Disc). The magnetic disk is, for example, a hard disk. Further, the computer program P1 may be downloaded from an external device (not shown) connected to a communication network (not shown), and the downloaded computer program P1 may be stored in the storage unit 53.

7 and 8 are flowcharts showing the procedure of the position calculation process. The calculation unit 49 repeatedly executes the position calculation process.
Hereinafter, the position calculation process executed by the calculation unit 49 of the transport vehicle 12a will be described. The calculation unit 49 of each of the transport vehicles 12b and 12c executes the position calculation processing in the same manner as the calculation unit 49 of the transport vehicle 12a. In the description of the position calculation process performed by the calculation unit 49 of the transport vehicle 12a, the position calculation process performed by the calculation unit 49 of the transport vehicle 12b can be described by replacing the transport vehicle 12a with the transport vehicle 12b. Similarly, in the description of the position calculation process performed by the calculation unit 49 of the transport vehicle 12a, the position calculation process performed by the calculation unit 49 of the transport vehicle 12c can be described by replacing the transport vehicle 12a with the transport vehicle 12c.

The storage unit 53 stores the value of the shielding flag for the transport vehicle 12a. The value of the occlusion flag is zero or one. When the value of the shielding flag is zero, it means that the transport vehicle 12a is not located in the shielding area. When the value of the shielding flag is 1, it means that the transport vehicle 12a is located in the shielding area. Further, the storage unit 53 stores arrangement information indicating the arrangement of the objects fixed in the room R.

First, the calculation unit 49 instructs the timer 51 to start timing (step S1), and determines whether or not the reception detection unit 47 has detected the reception of the radio signal (step S2).
When the calculation unit 49 determines that the reception detection unit 47 has detected the reception of the radio signal (S2: YES), the calculation unit 49 together with the transmission time information and the transmission source information included in the baseband signal input from the decoding unit 46. , Acquires the correlation value information input from the decoding unit 46 (step S3). Next, the calculation unit 49 acquires time information from the clock unit 50 (step S4). Here, the time indicated by the time information acquired by the calculation unit 49 is the reception time of the radio signal.

Next, the calculation unit 49 transmits a signal of the radio signal received by the receiving antenna 40 based on the transmission time indicated by the transmission time information acquired in step S3 and the reception time indicated by the time information acquired in step S4. The propagation time from the original to the receiving antenna 40 of the carrier 12a is calculated (step S5). The calculation unit 49 calculates, for example, the period from the transmission time to the reception time as the propagation time.

Next, the calculation unit 49 calculates the propagation distance of the radio signal received by the receiving antenna 40 from the signal transmission source to the receiving antenna 40 of the carrier vehicle 12a based on the propagation time calculated in step S5. (Step S6). For example, when it is considered that the room is in a vacuum, the calculation unit 49 calculates the propagation distance by multiplying the propagation time by the propagation speed of the radio signal in the vacuum. The propagation speed of a radio signal in a vacuum is represented by the product of 3 and 10 to the 8th power (unit: m / s).

Next, the calculation unit 49 stores the correlation value indicated by the correlation information acquired in step S3 and the propagation distance calculated in step S6 in association with the signal source indicated by the source information acquired in step S3. Store in 53 (step S7).
FIG. 9 is a chart showing the correlation value and the propagation distance associated with the signal transmission source. In step S7, for example, as shown in FIG. 9, the calculation unit 49 stores the correlation value Ma1 and the propagation distance La1 in association with the transmission station 10a which is the signal transmission source.

When the calculation unit 49 determines that the reception detection unit 47 has not detected the reception of the radio signal (S2: NO), or after executing step S7, the time counting time measured by the timer 51 is the reference time. It is determined whether or not it is the above (step S8). When the calculation unit 49 determines that the time counting time is less than the reference time (S8: NO), the calculation unit 49 executes step S2.

The calculation unit 49 stores the correlation value and the propagation time of the radio signal received by the receiving antenna 40 in association with the signal transmission source until the time counting time becomes equal to or longer than the reference time. As described above, the radio signals A1, A2, A3, B1, B2, B3, C1, C2, and C3 are sequentially transmitted from the transmitting stations 10a, 10b, and 10c each time a predetermined time elapses. The reference time is set to, for example, 9 times a predetermined time. As a result, by the time the time counting time exceeds the reference time, the receiving antennas 40 of the transport vehicles 12a, 12b, and 12c each have all of the radio signals A1, A2, A3, B1, B2, B3, C1, C2, and C3. It is possible to receive.

When all of the radio signals A1, A2, A3, B1, B2, B3, C1, C2, and C3 are received before the time counting time exceeds the reference time, they are associated with the signal transmission source as shown in FIG. The nine correlation values and the nine propagation distances are stored in the storage unit 53. For example, when the radio signal B3 does not reach the receiving antenna 40 of the carrier vehicle 12a by the time when the time counting time exceeds the reference time, eight correlation values and eight propagation distances are associated with the signal transmission source. Is stored in the storage unit 53.

When the calculation unit 49 determines that the time counting time is equal to or longer than the reference time (S8: YES), the calculation unit 49 instructs the timer 51 to end the time counting (step S9), and the correlation value for each of the transmitting stations 10a, 10b, and 10c. Selects the maximum propagation distance (step S10). The calculation unit 49 executes step S10 based on the correlation value and the propagation distance stored in the storage unit 53 before the time counting time becomes equal to or longer than the reference time. For each of the transmitting stations 10a, 10b, and 10c, the higher the correlation value, the better the reception state of the radio signal. Therefore, the propagation distance having the maximum correlation value is selected.

For example, it is assumed that the correlation value and the propagation distance are stored in the storage unit 53 by the time the timekeeping time becomes equal to or longer than the reference time, as shown in FIG. The calculation unit 49 selects the propagation distance corresponding to the maximum correlation value among the correlation values Ma1, Ma2, and Ma3 for the transmitting station 10a. When the correlation value Ma1 is the maximum correlation value, the propagation distance La1 is selected. Similarly, the calculation unit 49 selects the propagation distance corresponding to the maximum correlation value in the correlation values Mb1, Mb2, Mb3 for the transmitting station 10b, and the maximum among the correlation values Mc1, Mc2, Mc3 for the transmitting station 10c. Select the propagation distance corresponding to the correlation value of.

Next, the calculation unit 49 stores the three propagation distances selected in step S10 in the storage unit 53 (step S11). One of the transmitting stations 10a, 10b, and 10c is associated with each of these three propagation distances. As described above, the position calculation process is repeatedly executed. Therefore, the transition of the propagation distance is stored in the storage unit 53 for each of the transmitting stations 10a, 10b, and 10c.

Next, the calculation unit 49 determines whether or not the value of the occlusion flag is zero (step S12). When the calculation unit 49 determines that the value of the shielding flag is zero (S12: YES), the calculation unit 49 determines whether or not the transport vehicle 12a has invaded the shielding area (step S13). The propagation distance of the radio signal that is reflected by the reflector 13 and reaches the receiving antenna 40 of the transport vehicle 12a is longer than the propagation distance of the radio signal that directly reaches the receiving antenna 40 of the transport vehicle 12a from the signal transmission source.

Therefore, when the transport vehicle 12a invades the shielded area, the propagation distance of the radio signal transmitted by the transmission antennas 27 of the transmission stations 10b and 10c suddenly changes significantly. Therefore, for the radio signals transmitted by the transmitting antennas 27 of the transmitting stations 10b and 10c, the propagation distance selected in this step S10 is longer than the propagation distance selected in the previous step S10, and the difference between these propagation distances. When is equal to or greater than the predetermined first reference distance, the calculation unit 49 determines that the transport vehicle 12a has entered the shielded area. In other cases, the calculation unit 49 determines that the transport vehicle 12a has not entered the shielded area.

When the calculation unit 49 determines that the transport vehicle 12a has not entered the shielded area (S13: NO), the calculation unit 49 calculates the position of the transport vehicle 12a based on the three propagation distances selected in step S10 (step S14). ). The calculation unit 49 functions as a position calculation unit.
The calculation unit 49 calculates the position of the transport vehicle 12a by, for example, hyperbolic navigation. It is assumed that the calculation unit 49 selects the propagation distances La1, Lb1, and Lc1 corresponding to the transmission stations 10a, 10b, and 10c in step S10. In hyperbolic navigation, the calculation unit 49 indicates the position where the difference in distance between the transmission stations 10a and 10b is the absolute value of (La1-Lb1) at the coordinates indicating the positions of the transmission stations 10a, 10b and 10c. Draw a hyperbola, draw a second hyperbola indicating the position where the difference in distance between the transmitting stations 10b and 10c is the absolute value of (Lb1-Lc1), and set the intersection of the first and second hyperbolas to the position of the carrier 12a. Calculate as.

The first hyperbola is a hyperbola whose two focal points are the positions of the transmitting stations 10a and 10b. The second hyperbola is a hyperbola whose two focal points are the positions of the transmitting stations 10b and 10c. The positions of the transmission stations 10a, 10b, and 10c are the positions indicated by the coordinate information included in the baseband signal of the radio signal whose signal transmission source is the transmission stations 10a, 10b, and 10c.

The calculation unit 49 may calculate the position of the transport vehicle 12a by another method. For example, the calculation unit 49 draws a circle in which the center is the position of the transmission station 10a and the radius is the propagation distance La1 at the coordinates indicating the positions of the transmission stations 10a, 10b, and 10c, and the center is the position of the transmission station 10b. Draw a circle whose radius is the propagation distance Lb1 and whose center is the position of the transmitting station 10c and whose radius is the propagation distance Lc1. Then, the calculation unit 49 may calculate the intersection of the three circles as the position of the transport vehicle 12a.

When the calculation unit 49 determines that the transport vehicle 12a has entered the shielding area (S13: YES), the calculation unit 49 sets the value of the shielding flag to 1 (step S15). When the transport vehicle 12a is located in the shielded region, the calculation unit 49 includes the radio signals reflected by the reflector 13 in the three radio signals corresponding to the three propagation distances selected in step S10. .. Specifically, the radio signal transmitted from the transmitting stations 10b and 10c to the transport vehicle 12a is a radio signal reflected by the reflector 13.

The propagation distance of the radio signal transmitted from one transmitting station among the transmitting stations 10a, 10b, and 10c, reflected by the reflector 13, and reached the receiving antenna 40 of the transport vehicle 12a is directly from the same transmitting station. It is longer than the propagation distance of the radio signal that has reached the receiving antenna 40 of 12a. Therefore, when the transport vehicle 12a is located in the shielded area and the calculation unit 49 calculates the position of the transport vehicle 12a based on the three propagation distances selected in step S10, the exact position of the transport vehicle 12a Is never calculated.

Executing step S13 means that the reflector 13 is combined with three radio signals corresponding to the three propagation distances selected by the calculation unit 49 in step S10, that is, the three propagation distances used in the calculation of the position of the carrier 12a. It corresponds to determining whether or not the radio signal reflected by is included. Determining that the transport vehicle 12a has entered the shielded region in step S13 corresponds to determining that the three radio signals include the radio signal reflected by the reflector 13. Further, determining in step S13 that the transport vehicle 12a has not invaded the shielded region corresponds to determining that the three radio signals do not include the radio signal reflected by the reflector 13. The calculation unit 49 also functions as a signal determination unit.

As described in the description of step S17, in the position calculation process, the position calculated by the calculation unit 49 is stored in the storage unit 53. Further, since the position calculation process is repeatedly executed, the transition of the position calculated by the calculation unit 49 is stored in the storage unit 53.

After executing step S15, the calculation unit 49 calculates the position of the transport vehicle 12a based on the position of the transport vehicle 12a in the past, the vehicle information input from the Doppler measuring instrument 43, the arrangement information of the indoor R, and the like. (Step S16). The vehicle information input from the Doppler measuring instrument 43 and the arrangement information correspond to the related information related to the transport vehicle 12a.

After executing step S14 or step S16, the calculation unit 49 stores the calculated position of the transport vehicle in the storage unit 53 (step S17). After that, the calculation unit 49 instructs the output unit 52 to output the position data indicating the position calculated in step S14 or step S16 to the travel control device 31 (step S18).
After executing step S18, the calculation unit 49 ends the position calculation process. After completing the process, the calculation unit 49 executes the position calculation process again and repeats the calculation of the position of the transport vehicle 12a.

When it is determined that the value of the shielding flag is not zero, that is, the value of the shielding flag is 1 (S12: NO), the calculation unit 49 determines whether or not the transport vehicle 12a has left the shielding area ( Step S19). As described above, the propagation distance of the radio signal reflected by the reflector 13 and reaching the receiving antenna 40 of the transport vehicles 12a, 12b, 12c is the propagation distance of the radio signal directly reaching the receiving antenna 40 from the signal transmission source. Longer than the distance.

Therefore, when the transport vehicle 12a leaves the shielded area, the propagation distance of the radio signal transmitted by the transmission antennas 27 of the transmission stations 10b and 10c suddenly changes significantly. Therefore, for the radio signals transmitted by the transmitting stations 10b and 10c, the propagation distance selected in this step S10 is shorter than the propagation distance selected in the previous step S10, and the difference between these propagation distances is a predetermined thirst. When the distance is 2 reference distances or more, the calculation unit 49 determines that the transport vehicle 12a has separated from the shielded area. In other cases, the calculation unit 49 determines that the transport vehicle 12a has not separated from the shielded area.

Executing step S19 means that the reflector 13 is combined with three radio signals corresponding to the three propagation distances selected by the calculation unit 49 in step S10, that is, the three propagation distances used in the calculation of the position of the carrier 12a. It corresponds to determining whether or not the radio signal reflected by is included. Determining that the transport vehicle 12a has not separated from the shielded region in step S19 corresponds to determining that the three radio signals include the radio signal reflected by the reflector 13. Further, determining that the transport vehicle 12a has left the shielded region in step S19 corresponds to determining that the three radio signals do not include the radio signal reflected by the reflector 13.

When the calculation unit 49 determines that the transport vehicle 12a has not separated from the shielded area (S19: NO), the calculation unit 49 executes step S16, and subsequently, the position of the past transport vehicle 12a and the input from the Doppler measuring instrument 43 are input. The position of the transport vehicle 12a is calculated based on the vehicle information, the arrangement information of the interior R, and the like.
When the calculation unit 49 determines that the transport vehicle 12a has left the shielding region (S19: YES), the calculation unit 49 sets the value of the shielding flag to zero (step S20), and executes step S14. The calculation unit 49 returns the position calculation method to the calculation method performed based on the three propagation distances selected in step S10.

FIG. 10 is a block diagram showing a main configuration of the travel control device 31.
Hereinafter, the configuration of the travel control device 31 of the transport vehicle 12a will be described. The travel control device 31 of each of the transport vehicles 12b and 12c is configured in the same manner as the travel control device 31 of the transport vehicle 12a. In the description of the configuration of the travel control device 31 of the transport vehicle 12a, the configuration of the travel control device 31 of the transport vehicle 12b can be described by replacing each of the transport vehicles 12a and 12b with the transport vehicles 12b and 12a. Similarly, in the description of the configuration of the travel control device 31 of the transport vehicle 12a, the configuration of the travel control device 31 of the transport vehicle 12c can be described by replacing each of the transport vehicles 12a and 12c with the transport vehicles 12c and 12a. ..

The travel control device 31 includes input units 60 and 61, output units 62, wireless communication units 63, storage units 64, and control units 65. These are separately connected to the bus 66. The input unit 60 is connected to the output unit 52 of the position calculation device 30 in addition to the bus 66.

Position data indicating the position of the transport vehicle 12a calculated by the calculation unit 49 is input to the input unit 60 from the output unit 52 of the position calculation device 30 of the transport vehicle 12a. When the position data is input from the output unit 52, the input unit 60 gives the input position data to the control unit 65.
For example, a vehicle speed sensor (not shown) that detects the speed of the transport vehicle 12a is connected to the input unit 61. Vehicle speed data indicating the speed of the transport vehicle 12a is input to the input unit 61. The control unit 65 acquires vehicle speed data from the input unit 61. The speed of the transport vehicle 12a indicated by the vehicle speed data acquired by the control unit 65 from the input unit 61 is substantially the same as the speed of the transport vehicle 12a at the time when the vehicle speed data is acquired.

The output unit 62 is connected to a plurality of in-vehicle devices (not shown) included in the transport vehicle 12a. The output unit 62 outputs signals to these in-vehicle devices separately according to the instructions of the control unit 65. The control unit 65 controls the operation of the plurality of vehicle-mounted devices by causing the output unit 62 to output a signal, and controls the traveling of the transport vehicle 12a.

According to the instruction of the control unit 65, the wireless communication unit 63 wirelessly transmits to at least one of the transport vehicles 12b and 12c the travel data regarding the travel of the transport vehicle 12a and the completion data indicating the completion of the adjustment regarding the travel. Further, the wireless communication unit 63 receives travel data and completion data from the transport vehicles 12b and 12c, respectively. The wireless communication unit 63 functions as a data receiving unit.

The storage unit 64 is, for example, a non-volatile memory. The computer program P2 is stored in the storage unit 64. Various data are stored in the storage unit 64 by the control unit 65. Further, the data stored in the storage unit 64 is read out by the control unit 65.

The control unit 65 has a CPU (not shown). By executing the computer program P2, the CPU of the control unit 65 performs travel control processing, transmission processing for transmitting travel data to the transport vehicles 12b and 12c, and adjustments regarding the data transmission source of travel data and travel. The first adjustment process and the second adjustment process are executed. As a result, the CPU of the control unit 65 controls the operation of the transport vehicle 12a.

The computer program P2 may also be stored in the storage medium E2 so that the computer can read it. In this case, the computer program P2 read from the storage medium E2 by a reading device (not shown) is stored in the storage unit 64. The storage medium E2 is an optical disk, a flexible disk, a magnetic disk, a magnetic disk disk, a semiconductor memory, or the like. Further, the computer program P2 may be downloaded from an external device (not shown) connected to a communication network (not shown), and the downloaded computer program P2 may be stored in the storage unit 64.

Hereinafter, the traveling control process, the transmission process, the first adjustment process, and the second adjustment process executed by the control unit 65 of the transport vehicle 12a will be described. The control units 65 of the transport vehicles 12b and 12c each execute the travel control process, the transmission process, the first adjustment process, and the second adjustment process in the same manner as the control unit 65 of the transport vehicle 12a. By replacing the transport vehicles 12a and 12b with the transport vehicles 12b and 12a in each of the traveling control processing, the transmission processing, the first adjustment processing and the second adjustment processing executed by the control unit 65 of the transport vehicle 12a, the transport vehicle 12a The travel control process, the transmission process, the first adjustment process, and the second adjustment process executed by the control unit 65 can be described. By replacing the transport vehicles 12a and 12c with the transport vehicles 12c and 12a in each of the traveling control process, the transmission process, the first adjustment process and the second adjustment process executed by the control unit 65 of the transport vehicle 12a, the transport vehicle 12c The travel control process, the transmission process, the first adjustment process, and the second adjustment process executed by the control unit 65 can be described.

The control unit 65 repeatedly executes the travel control process. The storage unit 64 stores route data indicating a planned travel route on which the transport vehicle 12a is scheduled to travel. In the travel control process, the control unit 65 instructs the output unit 62 to output signals to a plurality of in-vehicle devices mounted on the transport vehicle 12a, thereby causing the transport vehicle 12a to have a planned travel route indicated by route data. To run.

FIG. 11 is a flowchart showing the procedure of the transmission process. The control unit 65 of the transport vehicle 12a executes a transmission process when position data is input to the input unit 60.
The control unit 65 first stores the position data input to the input unit 60 in the storage unit 64 (step S21), and plans to travel the transport vehicle 12a based on the position indicated by the position data input to the input unit 60. The route is determined (step S22). In step S22, the control unit 65 moves to, for example, a set position to be currently headed based on the position indicated by the position data input to the input unit 60, that is, the position calculated by the calculation unit 49 of the position calculation device 30. Determine the planned travel route. The control unit 65 functions as a determination unit.

Next, the control unit 65 updates the route data stored in the storage unit 64 with the route data indicating the planned travel route determined in step S22 (step S23). As described above, the transport vehicle 12a travels on the planned travel route indicated by the route data.
Next, the control unit 65 transmits the travel data indicating the planned travel route determined in step S22, the position and speed of the transport vehicle 12a, the travel priority of the transport vehicle 12a, and the like to the transport vehicles 12b and 12c. Instruct the wireless communication unit 63 (step S24). As a result, the wireless communication unit 63 wirelessly transmits the traveling data to the transport vehicles 12b and 12c. The wireless communication unit 63 also functions as a data transmission unit.
The control unit 65 ends the transmission process after executing step S24.

FIG. 12 is a flowchart showing the procedure of the first adjustment process. The control unit 65 acquires the travel data received wirelessly by the wireless communication unit 63 from the wireless communication unit 63. The control unit 65 executes the first adjustment process when the wireless communication unit 63 acquires the travel data received wirelessly.
In the first adjustment process, the control unit 65 determines whether or not to make adjustments regarding the data transmission source of the travel data and the travel based on the content indicated by the travel data received by the wireless communication unit 63 (step S31). ). For example, the control unit 65 determines whether the transport vehicle 12a comes into contact with the data transmission source of the travel data based on the position, speed, and planned travel route of the data transmission source and the position, speed, and planned travel route of the transport vehicle 12a. Judge whether or not. When the control unit 65 determines that the transport vehicle 12a comes into contact with the data transmission source, it determines that the travel adjustment should be performed, and when it determines that the transport vehicle 12a does not contact the travel data data transmission source, the control unit 65 makes the travel adjustment. Judge that it is not possible to do. The control unit 65 also functions as an adjustment determination unit.

When the control unit 65 determines that the adjustment regarding the data transmission source and the travel should be performed (S31: YES), the travel priority of the own vehicle, that is, the transport vehicle 12a, and the travel received by the wireless communication unit 63 Based on the priority included in the data, it is determined whether or not the own vehicle should make adjustments related to traveling (step S32). The traveling priority of the transport vehicle 12a is stored in advance in the storage unit 64. When the priority of the data transmission source included in the travel data is higher than the priority of the transport vehicle 12a, the control unit 65 determines that the own vehicle should make adjustments related to travel. When the priority of the data transmission source included in the travel data is lower than the priority of the transport vehicle 12a, the control unit 65 determines that the own vehicle should not make adjustments related to travel. The control unit 65 functions as a target determination unit.

When the control unit 65 determines that the own vehicle should make adjustments related to traveling (S32: YES), the control unit 65 determines the planned travel route and speed of the transport vehicle 12a based on the content indicated by the travel data received by the wireless communication unit 63. Adjustments related to running are made by changing at least one (step S33). As a result, contact between the transport vehicle 12a and the data transmission source can be avoided. The planned travel route of the transport vehicle 12a is changed by updating the planned travel route indicated by the route data. The speed of the transport vehicle 12a is the speed at which the transport vehicle 12a travels, and is changed by causing the output unit 62 to signal a change in speed. The change in speed also includes a temporary stoppage of the transport vehicle 12a.

After executing step S33, the control unit 65 instructs the wireless communication unit 63 to transmit the travel data whose contents have been changed to the transport vehicles 12b and 12c (step S34). As a result, the wireless communication unit 63 transmits the travel data whose contents have been changed to the transport vehicles 12b and 12c, and notifies the transport vehicles 12b and 12c that the travel adjustment has been performed.

When the control unit 65 determines that the own vehicle should not make adjustments related to traveling (S32: NO), the wireless communication unit 63 transmits the traveling data of the transport vehicle 12a and the instruction data instructing the adjustments related to traveling. (Step S35). As a result, the wireless communication unit 63 transmits the travel data and instruction data of the transport vehicle 12a to the data transmission source that transmitted the travel data to itself, that is, one of the transport vehicles 12b and 12c.

The control unit 65 determines whether or not the wireless communication unit 63 has received the completion data (step S36). As described above, the completion data is data indicating the completion of the adjustment related to running. When the control unit 65 determines that the wireless communication unit 63 has not received the completion data (S36: NO), the control unit 65 executes step S36 again and waits until the wireless communication unit 63 receives the completion data.

When the control unit 65 determines that the transport vehicle 12a should not make adjustments related to traveling (S31: NO), after executing step S34, or when the wireless communication unit 63 determines that the completion data has been received. (S36: YES), the first adjustment process is terminated.

FIG. 13 is a flowchart showing the procedure of the second adjustment process. The control unit 65 executes the second adjustment process when the wireless communication unit 63 receives the travel data and the instruction data from one of the transport vehicles 12b and 12c.
In the second adjustment process, the control unit 65 adjusts the travel by changing at least one of the planned travel route and the speed of the transport vehicle 12a based on the content indicated by the travel data received by the wireless communication unit 63. (Step S41). As a result, it is possible to avoid contact between the data transmission source of the traveling data and the instruction data and the transport vehicle 12a.

Next, the control unit 65 instructs the wireless communication unit 63 to transmit the completed data (step S42). As a result, the wireless communication unit 63 transmits the completion data to the data transmission source of the traveling data and the instruction data.
After executing step S42, the control unit 65 ends the second adjustment process.

In the communication system 1 configured as described above, when the three transport vehicles 12a, 12b, and 12c each receive the travel data, they travel with the data transmission source of the travel data based on the contents indicated by the received travel data. Determine if adjustments should be made. Therefore, each of the three transport vehicles 12a, 12b, and 12c can appropriately identify an object for which the traveling adjustment is made, for example, another transport vehicle that is likely to come into contact with the own vehicle.

For example, in FIG. 1, the distance between the transport vehicles 12a and 12b is short. However, as indicated by the solid arrows, the planned travel routes of the transport vehicles 12a and 12b do not intersect. Therefore, when the transport vehicle 12a receives the travel data from the transport vehicle 12b, it determines that the travel data transmission source and the travel adjustment should not be performed.

On the other hand, in FIG. 1, the distance between the transport vehicles 12a and 12c is long. However, as shown by the solid arrows, the planned travel routes of the transport vehicles 12a and 12c intersect. Therefore, when the transport vehicle 12a receives the travel data from the transport vehicle 12c, the transport vehicle 12a determines that the data transmission source of the travel data and the travel adjustment should be performed.

Further, since the reflector 13 is installed in the indoor R, the range in which the receiving antennas 40 of the three transport vehicles 12a, 12b, and 12c can receive the radio signal is wide in the indoor R. Further, the calculation unit 49 of each of the three transport vehicles 12a, 12b, and 12c includes the radio signal reflected by the reflector 13 in the three radio signals corresponding to the three propagation distances used in the calculation of the position. If it is determined, the position is calculated based on the vehicle information, the arrangement information, and the like input from the Doppler measuring instrument 43. As a result, each of the three transport vehicles 12a, 12b, and 12c can appropriately calculate the position of the own vehicle.

(Embodiment 2)
In step S32 of the first adjustment process, the index of whether or not the own vehicle should make adjustments for the transport vehicles 12a, 12b, and 12c is not limited to the priority of the own vehicle and the data transmission source.
Hereinafter, the difference between the second embodiment and the first embodiment will be described. Since the other configurations other than the configurations described later are common to the first embodiment, the same reference numerals as those of the first embodiment are assigned to the components common to the first embodiment, and the description thereof is omitted. To do.

Hereinafter, the transmission process and the first adjustment process executed by the control unit 65 of the transport vehicle 12a in the second embodiment will be described. The control units 65 of the transport vehicles 12b and 12c according to the second embodiment execute the transmission process and the first adjustment process in the same manner as the control unit 65 of the transport vehicle 12a according to the second embodiment. Transmission processing and first adjustment processing executed by the control unit 65 of the transport vehicle 12a By replacing the transport vehicle 12a with the transport vehicle 12b, the transmission processing and the first adjustment processing executed by the control unit 65 of the transport vehicle 12b are performed. Can be explained. Transmission processing and first adjustment processing executed by the control unit 65 of the transport vehicle 12a By replacing the transport vehicle 12a with the transport vehicle 12c, the transmission processing and the first adjustment processing executed by the control unit 65 of the transport vehicle 12c are performed. Can be explained.

In step S24 of the transmission process in the second embodiment, the control unit 65 of the travel control device 31 of the transport vehicle 12a determines the vehicle height, width, and weight of the transport vehicle 12a instead of the travel priority of the transport vehicle 12a. It is instructed to transmit the traveling data indicating at least one index of the above to the transport vehicles 12b and 12c.
In step S32 of the first adjustment process in the second embodiment, the control unit 65 uses the own vehicle, that is, the index of the transport vehicle 12a, and the index indicated by the traveling data received by the wireless communication unit 63. Determines whether or not to make travel adjustments.

Among the transport vehicle 12a and the data transmission source, the vehicle for which the adjustment regarding traveling should be made can be determined as follows.
As one example, the transport vehicle 12a and the lighter weight vehicle among the data transmission sources make adjustments related to travel. As another example, the transport vehicle 12a and the vehicle having a low vehicle height among the data transmission sources make adjustments related to traveling. Further, as another example, the transport vehicle 12a and the vehicle having a narrow vehicle width among the data transmission sources make adjustments related to traveling.
The communication system 1 and the transport vehicles 12a, 12b, 12c in the second embodiment have the same effects as those in the first embodiment.

In the first adjustment process according to the first and second embodiments, the control unit 65 executes step S33 when the wireless communication unit 63 does not receive the completion data for a predetermined period after executing step S35. May be good.
Further, the vehicle for which the adjustment regarding traveling is to be performed is not limited to one of the transport vehicle 12a and the data transmission source, and may be both. Further, the calculation units 49 of the transport vehicles 12a, 12b, and 12c each use the information used for the position calculation in step S16 of the position calculation process, for example, instead of the vehicle information input from the Doppler measuring instrument 43. Information output from the wheel speed sensor and indicating the wheel speed of the own vehicle may be used.

Further, the shape of the reflector 13 is not limited to the triangular columnar shape. Further, the number of reflectors 13 is not limited to one, and may be two or more. Further, the number of directions in which the transmitting stations 10a, 10b, and 10c each transmit radio signals is not limited to three, and may be one, two, or four or more. Further, the number of radio signals transmitted continuously by the transmitting stations 10a, 10b, and 10c is not limited to three, and may be two or four or more. Further, the transmitting stations 10a, 10b, and 10c do not have to continuously transmit radio signals.

Further, the number of transmitting stations is not limited to three, and may be four or more. Further, as long as the transport vehicles 12a, 12b, 12c are present in the indoor R, each of the transport vehicles 12a, 12b, 12c is a reflector when the radio signal can be directly received from at least three transmitting stations. It is not necessary to provide 13 in the room R. In this case, the position is always calculated based on the propagation distances of three radio signals from different signal sources.
Further, the number of transport vehicles traveling in the indoor R is not limited to three, and may be two or four or more. Further, the calculation unit 49 of the position calculation device 30 and the control unit 65 of the travel control device 31 may be configured by the same CPU. Further, the storage unit 53 of the position calculation device 30 and the storage unit 64 of the travel control device 31 may be configured by the same memory.

The disclosed embodiments 1 and 2 are exemplary in all respects and should be considered non-restrictive. The scope of the present invention is indicated by the scope of claims, not the meaning described above, and is intended to include all modifications within the meaning and scope equivalent to the scope of claims.

1 Communication system 10a, 10b, 10c Transmission station 12a, 12b, 12c Transport vehicle 13 Reflector 30 Position calculation device 31 Travel control device 40 Reception antenna (signal receiver)
49 Calculation unit (position calculation unit, signal judgment unit)
63 Wireless communication unit (data transmission unit, data reception unit)
65 Control unit (decision unit, adjustment judgment unit, target judgment unit)
P2 computer program

Claims (7)

Multiple transmitting stations that are fixed in a predetermined indoor position and transmit wireless signals,
A plurality of guided vehicles that travel in the chamber,
It is installed in the room and includes a reflector that reflects the radio signal toward between two shields that shield the radio signal .
Wherein the plurality of transport pullers people are
A signal receiving unit that receives radio signals transmitted by the plurality of transmitting stations, and
Among the radio signals received by the signal receiving unit, a position calculation unit that calculates the position of the own vehicle based on the propagation distances of a plurality of radio signals whose sources are different from each other.
A determination unit that determines a planned travel route based on the position calculated by the position calculation unit, and a determination unit that determines the planned travel route.
A data transmission unit that wirelessly transmits travel data indicating a planned travel route determined by the determination unit to another carrier, and a data transmission unit.
A data receiving unit that receives the traveling data from another transport vehicle, and
Based on the travel data received by the data reception unit, an adjustment determination unit that determines whether or not adjustments should be made to the source of the travel data and travel , and
A plurality of radio signals corresponding to each of the plurality of the propagation distances husband used in the calculation of the position calculating section, possess a determining signal determining unit whether contains radio signal reflected by the reflector,
The position calculation unit is characterized in that when it is determined by the signal determination unit that the radio signal reflected by the reflector is included, the position calculation unit calculates the position of the own vehicle based on the related information related to the own vehicle. Communication system. The relevant information indicates whether or not the carrier is close to the reflector.
The communication system according to claim 1. The communication system according to claim 1 or 2, wherein the adjustment related to the traveling is performed by changing at least one of the planned traveling route and the traveling speed. The travel data further indicates the travel priority with respect to the source of the travel data.
When the adjustment determination unit determines that the adjustment regarding the travel should be performed, the plurality of transport vehicles each have a travel priority related to the own vehicle and a priority indicated by the travel data received by the data receiving unit. The communication system according to any one of claims 1 to 3, further comprising a target determination unit for determining whether or not the own vehicle should make adjustments related to traveling. The travel data further indicates at least one index in vehicle height, vehicle width and weight from which the travel data is transmitted.
Each of the plurality of transport vehicles said, based on the index of the own vehicle and the index indicated by the travel data received by the data receiving unit, when the adjustment determination unit determines that the adjustment related to the traveling should be performed. The communication system according to any one of claims 1 to 3, further comprising an object determination unit for determining whether or not the own vehicle should make adjustments related to traveling. A carrier vehicle that travels in a room where a reflector that reflects a radio signal is installed between two shields that shield the radio signal.
A signal receiver that receives wireless signals and
Among the radio signals received by the signal receiving unit, a position calculation unit that calculates the position of the own vehicle based on the propagation distances of a plurality of radio signals whose sources are different from each other.
A determination unit that determines a planned travel route based on the position calculated by the position calculation unit, and a determination unit that determines the planned travel route.
A data transmission unit that wirelessly transmits travel data indicating the planned travel route determined by the determination unit, and
A data receiving unit that receives the driving data and
Based on the travel data received by the data reception unit, an adjustment determination unit that determines whether or not adjustments should be made to the source of the travel data and travel , and
A signal determination unit for determining whether or not the radio signal reflected by the reflector is included in the plurality of radio signals corresponding to the plurality of propagation distances used in the calculation of the position calculation unit is provided .
The position calculation unit is characterized in that when it is determined by the signal determination unit that the radio signal reflected by the reflector is included, the position calculation unit calculates the position of the own vehicle based on the related information related to the own vehicle. Transport vehicle. A computer program that causes a computer mounted on a transport vehicle traveling in a room where a reflector that reflects a radio signal toward a shield that shields the radio signal is installed to control the operation of the transport vehicle. ,
The position of the carrier is calculated based on the propagation distances of a plurality of radio signals having different sources .
It is determined whether or not the radio signals reflected by the reflector are included in the plurality of radio signals corresponding to the plurality of propagation distances used in the calculation of the position of the carrier.
When it is determined that the radio signal reflected by the reflector is included, the position of the transport vehicle is calculated based on the related information related to the transport vehicle.
Based on the calculated position of the transport vehicle, the planned travel route on which the transport vehicle is scheduled to travel is determined.
Instructs wireless transmission of travel data related to travel, including route data indicating the determined travel route.
Acquires driving data received wirelessly and
A computer program characterized in that a computer is made to execute a process of determining whether or not the transport vehicle should make adjustments regarding the transmission of the travel data and travel based on the acquired travel data.

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