JP6581955B2 - Vehicle state detection system and vehicle - Google Patents

Description

  The present invention relates to a vehicle state detection system and a vehicle.

  As a technique for determining the traveling direction of a vehicle, Patent Document 1 states that “two responders 12 and 13 are attached to a train 11 at intervals, one interrogator is provided on the ground side, The interval is set so that when one passes the communication range of the interrogator, the other enters the communication range.The responders 12, 13 received at the interrogator side when the train 11 passes through the interrogator point. The train traveling direction is determined in this order, and whether or not the area is between the responders 12 and 13 is determined by the peak monitoring of the correlation value.

JP 2002-48862 A

  Although the technique which determines the advancing direction of a vehicle is described in patent document 1, the description regarding the technique which determines the direction of a vehicle is not found. For example, when traveling by connecting a carriage to the rear of the vehicle, if a certain point is passed forward in a north direction, the vehicle and the carriage pass in this order. On the other hand, if the same point is passed backwards northward, it will pass in order of a trolley | bogie and a vehicle. Therefore, in order to ensure a safety margin against walls and other vehicles when the vehicle is traveling, there is a problem that it is necessary to determine the direction of the vehicle in addition to the traveling direction of the vehicle.

  Accordingly, an object of the present invention is to provide a technique capable of determining both the direction and the traveling direction of a vehicle.

  In order to solve the above problems, one of the desirable embodiments of the present invention is as follows. A vehicle state detection system including a vehicle and a ground device, wherein the ground device transmits a beacon by radio wave, the vehicle receives a beacon, and notifies a received radio wave intensity of the received beacon. A communication device and an arithmetic device that determines a direction and a traveling direction of the vehicle based on the received radio wave intensity and the order notified from each of the plurality of communication devices.

  ADVANTAGE OF THE INVENTION According to this invention, the technique which can determine the direction and the advancing direction of a vehicle collectively can be provided.

It is an example of the vehicle state detection system in Example 1. FIG. 3 is an example of a communication and determination sequence in the first embodiment. It is an example of the received radio wave intensity in the first embodiment. It is an example of the flowchart which determines the direction and the advancing direction of the vehicle in Example 1. FIG. It is an example of the vehicle state detection system in Example 2. FIG. It is an example of the sequence of communication and determination in Example 2. It is an example of the received radio wave intensity in the second embodiment. 10 is an example of a flowchart for determining a direction and a traveling direction of a vehicle in the second embodiment.

  Embodiments of the present invention will be described in detail with reference to the drawings. The embodiments described below are examples of the present invention, and the present invention is not limited to the following embodiments.

  FIG. 1 is a diagram illustrating an example of a vehicle state detection system according to the first embodiment. The vehicle state detection system includes, for example, at least one vehicle 100 and at least one ground device 110. In FIG. 1, the state seen from diagonally backward of the vehicle 100 and the state seen from the upper side of the vehicle are illustrated in correspondence, and the same reference numerals are given to the same objects in these two states.

  The vehicle 100 is, for example, an AGV (Automatic Guided Vehicle), an automobile, a train, or the like. The vehicle 100 preferably has a front 122 and a rear 123. The front 122 is, for example, a direction or a portion facing a general automobile driver, and the rear 123 is a direction or a portion opposite to the front 122 in a movable direction of the automobile, for example.

  However, the front 122 and the rear 123 are not limited to this, and may be determined from some structure of the vehicle 100 or may be defined in design or the like. In the movement of the vehicle 100, the movement in the direction of the front 122 is forward movement, the movement in the direction of the rear 123 is backward movement, and the forward movement and backward movement are the directions of the vehicle 100. In addition, the left and right with respect to the direction from the rear 123 to the front 122 are the left and right of the vehicle 100.

  The passage 130 is, for example, an AGV guide, a car road, a train track (track), or the like. The passage 130 has two directions in which the vehicle 100 can move. Regardless of which direction the vehicle actually moves, there are a direction A120 and a direction B121 as directions unique to the passage 130. When the vehicle 100 moves toward the direction A120 or the direction B121, the direction A120 or the direction B121 toward the direction becomes the traveling direction of the vehicle 100.

  The width of the passage 130 is not limited to the example illustrated in FIG. 1, but is desirably close to the width of the vehicle 100 that is substantially parallel to the width direction of the passage 130 when the vehicle 100 moves through the passage 130. . For this reason, in the case where the passage 130 is a road with a plurality of lanes, it is desirable that each of the lanes is a single lane in the plurality of lanes.

  The vehicle 100 and the passage 130 are not limited to the above examples. Any object can be used as long as the vehicle 100 moves along the passage 130. The vehicle 100 shown in FIG. 1 moves forward or backward on the passage 130 in the direction A120 or the direction B121. In particular, in the example of FIG. 1, the vehicle 122 moves forward in the direction A120 because the front 122 of the vehicle 100 proceeds in the direction A120 in order to move in the traveling direction 105.

  When the traveling direction of the vehicle 100 is a direction B121 opposite to the traveling direction 105 shown in FIG. 1, the vehicle 100 moves from the ground device 110 toward the direction B121 from the direction A120 to the top of the ground device 110. Pass forward or backward.

  The vehicle 100 includes at least two communication devices (communication device A 101 and communication device B 102), a calculation device 103, and a screen device 104. The communication device A 101 and the communication device B 102 are communication devices for wirelessly communicating with the ground device 110 installed on the passage 130 using radio waves. The communication device A 101 and the communication device B 102 are installed at a location away from the bottom surface of the vehicle 100.

  In the example of FIG. 1, the communication device A101 is installed on the bottom left front surface of the vehicle, the communication device B102 is installed on the bottom right rear surface of the vehicle, and there is no radio wave transmission / reception between the communication device A101, the communication device B102, and the ground device 110. Directivity and transmission output is constant. Thereby, it is possible to cause a difference in received radio wave intensity when each communication device communicates with the ground device 110 and to cause a difference in timing of starting communication.

  Here, the ideal installation interval between the communication device A 101 and the communication device B 102 varies depending on the assumed moving speed of the vehicle 100. Specifically, as the vehicle 100 moves at a higher speed, the installation interval between the communication device A 101 and the communication device B 102 is widened, thereby causing a clear difference in the timing at which each communication device communicates with the ground device 110. be able to.

  The arithmetic device 103 performs a determination process of the direction and the traveling direction of the vehicle 100 based on the result of the communication device A 101 and the communication device B 102 communicating with the ground device 110. Details of the determination process of the direction and the traveling direction of the vehicle 100 will be described later. The screen device 104 displays the determination result of the arithmetic device 103. The displayed information includes, for example, the direction and traveling direction of the vehicle 100, the ID (Identification) of the ground device 110 that has communicated with each communication device, and the like. The screen device 104 is, for example, a display device.

  In addition to the screen device 104, an information input device for giving an instruction to each device may be provided in the vehicle 100. The apparatus for outputting information and inputting information may be configured to be connected from the outside of the vehicle 100 via a communication network or a communication cable. Furthermore, the arithmetic device 103 may be composed of one computer or a plurality of computers.

  The ground device 110 periodically transmits a beacon by radio. The beacon transmitted by the ground device 110 includes at least an ID for identifying the ground device 110. Alternatively, an inquiry / response communication protocol may be used in which a beacon is transmitted from each communication device and the ground device 110 returns a response including the ID information of the ground device 110.

  In the case of the inquiry / response type communication protocol, in order to avoid radio interference between the beacon transmitted by the communication device A101 and the beacon transmitted by the communication device B102, the installation interval between the communication device A101 and the communication device B102 is increased. It is desirable to do. And according to the speed of the vehicle 100, the transmission interval of beacons from each communication device may be controlled.

  The ground device 110 is installed on the passage 130 at a location that is biased to one of the centers 131 of the passage 130. In the example of FIG. 1, the ground device 110 is installed at a location biased to the right in the direction A120. As a result, since the communication device A 101 and the communication device B 102 are also biased to the left and right sides of the vehicle 100, a difference occurs in the maximum value of the received radio wave intensity when each communication device communicates with the ground device 110. Can be made.

  FIG. 2 is a diagram illustrating an example of a sequence in which the vehicle 100 illustrated in FIG. 1 performs wireless communication with the ground device 110 and determines the direction and traveling direction of the vehicle 100. First, the ground device 110 periodically transmits a beacon (step 200). However, when each communication device and the ground device 110 exist at a distant place, wireless communication cannot be performed.

  Here, the ground device 110 may start periodic beacon transmission in response to some external signal. For example, the approximate position of the vehicle 100 may be detected outside, and transmission may be started in response to a signal based on the position. Further, the ground device 110 may have a clock, and transmission may be started according to a preset time.

  In the example of FIG. 1, since the vehicle 100 is moving in the traveling direction 105, the communication apparatus A101 enters the range 271 in which the communication with the ground apparatus 110 is possible, and wireless communication between the communication apparatus A101 and the ground apparatus 110 is started first. The That is, the ground device 110 transmits a beacon (step 210), the communication device A101 receives the transmitted beacon (step 211), and the communication device A101 notifies the arithmetic device 103 of the communication result (step 212).

  This communication result includes at least the ID of the ground device 110 and information on the received radio wave intensity when the beacon is received. The arithmetic device 103 that has received the communication result, the ID of the communication device A 101 that is the transmission source of the communication result, the time at which the communication result was received (the notified time), the ID of the ground device 110, and the information on the received radio wave intensity Is recorded (step 213).

  As the vehicle 100 moves, the communication device B102 also enters the range 272 in which communication with the ground device 110 is possible, and both the communication device A101 and communication device B102 may be able to communicate with the ground device 110. In this case, when the ground device 110 transmits a beacon (step 220), both the communication device A101 and the communication device B102 receive the beacon (steps 221 and 225).

  Then, the communication device A 101 and the communication device B 102 respectively notify the communication result to the arithmetic device 103 (steps 222 and 226), and the arithmetic device 103 sends the ID of each communication device that is the transmission source of the communication result and the communication result. Information about the received time, the ID of the ground device 110, and the received radio wave intensity is recorded (steps 223 and 227), respectively.

  Further, even when the vehicle 100 moves, both the communication device A 101 and the communication device B 102 may exist within the communication range of the ground device 110. Steps 230 to 237 in this case are the operations described in steps 220 to 227.

  When the vehicle 100 further moves, the communication device A101 may go out of the communication range 271 of the ground device 110, and the communication device B102 may exist within the communication range 272 of the ground device 110. In this case, when the ground device 110 transmits a beacon (step 240), the communication device B102 receives the beacon (step 241), and the communication device B102 notifies the arithmetic device 103 of the communication result (step 242).

  Receiving the communication result, the arithmetic device 103 records the ID of the communication device B102 that is the transmission source of the communication result, the time when the communication result is received, the ID of the ground device 110, and the information on the received radio wave intensity (step 243). ). After communication device B102 goes out of range 272 in which it can communicate with ground device 110, ground device 110 may transmit a beacon (step 260), elapse of a preset time, and a preset number of times. Beacon transmission, a preset time, etc. may be detected to terminate beacon transmission.

  When the arithmetic device 103 detects that the communication result is not notified from both the communication device A101 and the communication device B102, for example, when the arithmetic device 103 detects that the notification is not notified even after a preset time, the arithmetic device 103 performs a determination process of the direction and the traveling direction of the vehicle 100. Perform (step 250). Details of the determination process of the direction and the traveling direction of the vehicle 100 will be described later. The arithmetic unit 103 notifies the determination result to the screen device 104 (step 251), and when the screen device 104 receives the determination result (step 252), the determination result is displayed (step 253).

  In the above description, the case where the screen device 104 is mounted on the vehicle 100 has been described. However, the arithmetic device 103 communicates with a smartphone or a tablet terminal wirelessly or in a wired manner, and information related to the determination result is transmitted to these devices. May be displayed. In addition to the screen device 104, an audio output device may be used for outputting the determination result.

  FIG. 3 is a diagram illustrating an example in which the received radio wave intensity is graphed based on the communication result of each communication device and the ground device 110 recorded by the arithmetic device 103 and information on the time. A broken line 300 in this graph indicates a communication result between the communication device A 101 and the ground device 110, and an alternate long and short dash line 310 indicates a communication result between the communication device B 102 and the ground device 110. Note that beacon transmission by the ground device 110 is periodic, but for convenience, this graph is represented by a broken line connecting the relationship between discrete time and received radio wave intensity.

  As shown by a broken line 300 in FIG. 3, in the example of FIG. 1, the communication device A101 is installed in the traveling direction 105 of the vehicle 100, so the received radio wave intensity of the communication device A101 is generated first (time 302). Wireless communication between A101 and the ground device 110 is started first.

  Since the beacon transmitted by the ground device 110 is a radio wave, the electric field strength of the radio wave in the communication device A101 gradually increases. When the predetermined electric field strength is reached, information contained in the beacon can be extracted, and communication is performed. A received radio wave intensity that can be detected by apparatus A101 is generated. Thereby, at time 302, communication apparatus A101 and ground apparatus 110 can perform wireless communication.

  As the vehicle 100 (communication device A 101) approaches the ground device 110, the received radio wave intensity increases. When the ground device 110 reaches the front 122 of the vehicle 100, the received radio wave intensity becomes the maximum value from time 303 to time 304. 301. Thereafter, the received radio wave intensity decreases as the communication apparatus A 101 and the ground apparatus 110 move away, and the electric field intensity capable of wireless communication cannot be obtained (time 305). Here, the range from time 302 to time 305 is the range 271 shown in FIG.

  On the other hand, when the radio wave of the beacon reaches a predetermined electric field strength, the communication device B102 also generates a received radio wave strength (time 312), and wireless communication between the communication device B102 and the ground device 110 is started. The received radio wave intensity increases as the communication apparatus B102 approaches the ground apparatus 110. When the communication apparatus B102 reaches near the ground apparatus 110, the received radio wave intensity reaches the maximum value 311 from time 313 to time 314. Become.

  When the communication device B102 passes near the ground device 110, wireless communication is performed at a location closer to the ground device 110 than the communication device A101. Therefore, the maximum value 311 of the received radio wave intensity is the maximum value 301. Become bigger. Thereafter, the received radio wave intensity decreases as the communication apparatus B102 and the ground apparatus 110 move away, and the electric field intensity capable of wireless communication cannot be obtained (time 315). Here, the range from time 312 to time 315 is the range 272 shown in FIG.

  As will be described later, in order to compare the maximum value 301 and the maximum value 311, the beacon transmission interval by the ground device 110 is transmitted at least once from both time 303 to time 304 and from time 313 to time 314. Interval is set. For example, the distance between the communication device A 101 and the communication device B 102 and the distance of the component parallel to the traveling direction 105 is divided by the maximum speed set in the vehicle 100 or the passage 130, and the division result is halved. May be an interval. Moreover, the interval shorter than this time may be sufficient, and the irregular interval which can reproduce the graph shown in FIG. 3 may be sufficient.

  FIG. 4 is a diagram illustrating an example of a flowchart of the determination process of the direction and the traveling direction of the vehicle 100. This determination process corresponds to step 250 shown in FIG. The arithmetic device 103 determines whether or not the IDs of the ground devices 110 recorded in step 223 and step 227 are the same ID (step 400). When there are a plurality of ground devices 110 and the beacons transmitted by other ground devices are mixed and received, it is determined that the IDs are different, and the determination processing is terminated (step 408).

  In the example of FIGS. 1 and 2, since there is one ground device 110, it is determined that the IDs are the same, and the process proceeds to step 401, where the computing device 103 is a communication device that has started communication with the ground device 110. It is determined whether it is A101 or communication device B102 (step 401). As shown in FIGS. 1 to 3, in this example, since the time of notification from the communication device A101 is recorded as the previous time in step 213, the communication device A101 starts wireless communication first. Determine and proceed to step 402.

  The arithmetic device 103 compares the maximum value of the received radio wave intensity when each communication device performs wireless communication with the ground device 110 (step 402). As shown in FIG. 3, in this example, it is determined that the communication apparatus B102 is performing wireless communication with a larger received radio wave intensity, and the process proceeds to step 404. Then, it is determined that the vehicle 100 is “forward” and traveling in the “direction A120” (step 404), and the determination process is terminated (step 408).

  If the arithmetic device 103 determines in step 402 that the communication device A101 is performing wireless communication with a larger received radio wave intensity, the arithmetic device 103 proceeds to step 403, and the vehicle 100 proceeds in the “direction B121” in “forward”. As a result of determination, the determination process is terminated (step 408).

  On the other hand, when the arithmetic device 103 determines in step 401 that the communication device B102 has started wireless communication first, the processing device 103 proceeds to step 405, and each communication device wirelessly communicates with the ground device 110 in the same manner as in step 402. Compare the maximum value of the received radio wave intensity when communicating.

  If the arithmetic device 103 determines in step 405 that the communication device A101 is performing wireless communication with a higher received radio wave intensity, the arithmetic device 103 proceeds to step 406, and the vehicle 100 proceeds “reverse” to “direction A120”. As a result of determination, the determination process is terminated (step 408).

  If it is determined in step 405 that the communication device B102 is performing wireless communication with a larger received radio wave intensity, the arithmetic unit 103 proceeds to step 407, and the vehicle 100 is "reversed" in the "direction B121". The determination process is terminated with the progress as a determination result (step 408).

  In the above description, when the communication device A101 is installed on the left front side of the vehicle 100, the communication device B102 is installed on the right rear side of the vehicle 100, and the ground device 110 is installed on the right side in the direction A120 on the passage 130, Although the example which determines the direction and the advancing direction of the vehicle 100 was demonstrated, a present Example is not limited to it.

  For example, the communication device A101 may be installed on the left rear side of the vehicle 100, and the communication device B102 may be installed on the right front side of the vehicle 100. Furthermore, each communication device only needs to be installed at diagonal positions in the combination of front and rear and left and right of the vehicle 100. Moreover, the ground device 110 should just be installed not in the center 131 on the channel | path 130 but in either direction right and left toward the direction A120.

  When each communication device and the ground device 110 are installed in this manner, the direction and the traveling direction of the vehicle 100 are determined by performing the same determination process as the determination process (step 250) of the direction and the traveling direction of the vehicle 100. Can be uniquely determined.

  In the first embodiment, an example of a system including a plurality of communication devices for one ground device has been described. In the second embodiment, an example of a system including a plurality of ground devices for one communication device will be described. FIG. 5 is a diagram illustrating an example of a vehicle state detection system according to the second embodiment. The vehicle state detection system includes, for example, at least one vehicle 500, at least two ground devices A510, and a ground device B511.

  The configuration shown in FIG. 5 corresponds to the configuration shown in FIG. 1, and the vehicle 500, traveling direction 505, direction A520, direction B521, front 522, rear 523, passage 530, and center 531 shown in FIG. 1, the traveling direction 105, the direction A 120, the direction B 121, the front 122, the rear 123, the passage 130, and the center 131 are not described here, and the vehicle state detection system shown in FIG. It demonstrates centering on a different part.

  The communication device 501 is installed not in the center of the bottom surface of the vehicle 500 but in a place biased to either the left or right. In the example of FIG. 5, the communication device 501 is installed on the bottom left front of the vehicle. Thereby, a difference can be caused in the received radio wave intensity when the communication device 501 communicates with each ground device.

  Arithmetic device 503 performs determination processing of the direction and traveling direction of vehicle 500 based on the result of communication device 501 communicating with ground device A 510 and ground device B 511. Although details of the determination process of the direction and the traveling direction of the vehicle 500 will be described later, the arithmetic device 503 includes an ID pair table 506. The ID pair table 506 is a table in which, for example, the ID of the ground device A510 and the ID of the ground device B511 are registered in advance as a pair.

  By referring to the information in the ID pair table 506, the arithmetic device 503 can specify information related to the beacon from the ground device A510 even when there is a ground device other than the ground device A510 and the ground device B511. The information regarding the beacon can be specified, and further, it can be specified that the information is the target of the determination process.

  The screen device 504 displays the determination result of the arithmetic device 503. The displayed information includes, for example, the direction and traveling direction of the vehicle 500, the ID of each ground device that has communicated with the communication device 501, and the like. The screen device 504 is, for example, a display device.

  In addition to the screen device 504, an information input device for giving an instruction to each device may be provided in the vehicle 500, and information in the ID pair table 506 may be set. The apparatus for outputting information and inputting information may be configured to be connected from the outside of the vehicle 500 via a communication network or a communication cable. Furthermore, the arithmetic device 503 may be configured by one computer or a plurality of computers.

  The ground device A 510 and the ground device B 511 are installed on the passage 530 at locations that are offset in the left and right directions with respect to the center 531 of the passage 530. In the example of FIG. 5, the ground device A <b> 510 is installed at a location biased to the right side in the direction A <b> 520. In addition, the ground device B511 is installed at a location that is biased to the left side (the side opposite to the ground device A510) in the direction A520. Thereby, it is possible to cause a difference in the maximum value of the received radio wave intensity when the communication device 501 performs wireless communication with each ground device.

  In addition, the ground device A 510 and the ground device B 511 are installed at different locations in the traveling direction 505. In the example of FIG. 5, the ground device A510 is installed on the side near the direction B521, and the ground device B511 is installed on the side near the direction A520. Thereby, a difference can be made in the timing which the communication apparatus 501 starts wireless communication with each ground apparatus.

  Further, the ideal installation interval between the ground device A 510 and the ground device B 511 varies depending on the assumed communicable range of each ground device. Specifically, since the influence of radio interference between ground devices increases as the communicable range of each ground device increases, it is desirable to increase the installation interval between the ground devices. On the other hand, by using existing techniques such as transmission timing control and spreading code, the influence of radio interference between the ground devices may be reduced, and the installation interval between the ground devices may be shortened.

  Each of ground device A 510 and ground device B 511 periodically transmits a beacon by radio. The beacon transmitted by each ground device includes at least an ID for identifying each ground device. Alternatively, an inquiry / response communication protocol in which a beacon is transmitted from the communication device 501 and each ground device returns a response including its own ID information may be used.

  FIG. 6 is a diagram illustrating an example of a sequence in which the vehicle 500 illustrated in FIG. 5 performs wireless communication with each ground device and determines the direction and traveling direction of the vehicle 500. First, the ground device A 510 and the ground device B 511 periodically transmit beacons (steps 610 and 611). However, when the communication device 501 and each ground device exist at a distance, wireless communication cannot be performed.

  Here, the ground device A 510 and the ground device B 511 may start periodic transmission of beacons in response to some external signal. For example, the approximate position of the vehicle 500 may be detected outside, and transmission may be started in response to a signal based on that position. Further, the ground device A 510 and the ground device B 511 may have a clock, and transmission may be started according to a preset time.

  In the example of FIG. 5, since the vehicle 500 is moving in the traveling direction 505, the communication device 501 enters a range 692 in which communication with the ground device A510 is possible, and wireless communication between the communication device 501 and the ground device A510 is started first. The That is, ground device A 510 transmits a beacon (step 620), communication device 501 receives the transmitted beacon (step 621), and communication device 501 notifies communication device 503 of the communication result (step 622).

  This communication result includes at least the ID of the ground device A510 and information on the received radio wave intensity when the beacon is received. Receiving the communication result, the arithmetic device 503 records the time when the communication result is received (the notified time), the ID of the ground device A 510, and information on the received radio wave intensity (step 623).

  Here, the ground device B511 also transmits a beacon (step 611), but does not reach the communication device 501 because it is not within a communicable range. Then, the vehicle 500 further moves, and the same sequence as from step 620 to step 624 is repeated from step 630 to step 634 and from step 640 to step 644. For example, if the transmission of the beacon in step 630 is performed when the communication device 501 and the ground device A 510 are closest, in step 633, information regarding the maximum value of the received radio wave intensity is recorded.

  As the vehicle 500 moves, the communication device 501 exits from the communicable range 692 of the ground device A510, and wireless communication between the communication device 501 and the ground device A510 is interrupted. Instead, the communication device 501 communicates with the ground device B511. It may fall within the possible range 693. In this case, even if the ground device A 510 transmits a beacon (step 650), it does not reach the communication device 501.

  Then, the ground device B511 transmits a beacon (step 654), the communication device 501 receives the transmitted beacon (step 651), and the communication device 501 notifies the arithmetic device 503 of the communication result (step 652). This communication result includes at least the ID of the ground device B511 and information regarding the received radio wave intensity when the beacon is received.

  Receiving the communication result, the arithmetic device 503 records the time when the communication result is received (notified time), the ID of the ground device B511, and information on the received radio wave intensity (step 653). The vehicle 500 further moves, and the same sequence as from step 650 to step 654 is repeated from step 660 to step 664 and from step 670 to step 674.

  For example, if the transmission of the beacon in step 664 is performed when the communication device 501 and the ground device B 511 are closest to each other, information on the maximum value of the received radio wave intensity is recorded in step 663. Thereafter, the communication device 501 exits from the communicable range 693 of the ground device B511, and the wireless communication between the communication device 501 and the ground device B511 is also interrupted.

  When the communication device 501 no longer notifies the result of communication with each ground device, for example, when the arithmetic device 503 detects that notification is not made even after a preset time, the arithmetic device 503 performs a determination process of the direction and traveling direction of the vehicle 500. (Step 680). Details of the determination process of the direction and the traveling direction of the vehicle 500 will be described later. The arithmetic device 503 notifies the determination result to the screen device 504 (step 681), and when receiving the determination result (step 682), the screen device 504 displays the determination result (step 683).

  In the above description, the case where the screen device 504 is mounted on the vehicle 500 has been described. However, the arithmetic device 503 communicates with a smartphone or a tablet terminal wirelessly or in a wired manner, and information on a determination result is transmitted to these devices. May be displayed. In addition to the screen device 504, an audio output device may be used for outputting the determination result.

  FIG. 7 is a diagram illustrating an example in which the received radio wave intensity is graphed based on communication results between the communication device 501 and each ground device recorded by the arithmetic device 503 and information on time. A broken line 700 in this graph indicates a communication result between the communication device 501 and the ground device A 510, and an alternate long and short dash line 710 indicates a communication result between the communication device 501 and the ground device B 511. Note that beacon transmission by the ground device A510 and the ground device B511 is periodic, but for convenience, this graph is represented by a broken line connecting the relationship between discrete time and received radio wave intensity.

  As shown by the broken line 700 in FIG. 7, in the example of FIG. 5, the ground device A <b> 510 is installed on the side close to the vehicle 500 in the traveling direction 505 of the vehicle 500. (Time 702), the wireless communication between the communication device 501 and the ground device A510 is started first.

  Note that since the beacon transmitted by the ground device A510 is a radio wave, the electric field strength of the radio wave in the communication device 501 gradually increases, and when the predetermined electric field strength is reached, information contained in the beacon can be extracted and communication is performed. A received radio wave intensity that can be detected by the apparatus 501 is generated. Thereby, at time 702, the ground device A 510 and the communication device 501 can perform wireless communication.

  As the vehicle 500 (communication device 501) approaches the ground device A510, the received radio wave intensity increases. When the ground device 110 reaches the front 522 of the vehicle 500, the received radio wave intensity reaches the maximum value from time 703 to time 704. 701. Thereafter, the received radio wave intensity decreases as the communication apparatus 501 and the ground apparatus A 510 are separated, and the electric field intensity capable of wireless communication cannot be obtained (time 705). Here, the range from time 702 to time 705 is the range 692 shown in FIG.

  On the other hand, the electric field strength of the ground device B511 also increases as it approaches the communication device 501, but the radio wave of the beacon reaches a predetermined electric field strength and the received radio wave strength is generated at time 712. The received radio wave intensity increases as the communication device 501 approaches the ground device B511. When the communication device 501 reaches near the ground device B511, the received radio wave intensity reaches the maximum value 711 as from time 713 to time 714. Become.

  When the communication device 501 passes near the ground device B511, wireless communication is performed in a place closer to the communication device 501 than the ground device A510, and therefore the maximum value 711 of the received radio wave intensity is the maximum value 701. Become bigger. Thereafter, the received radio wave intensity decreases as the communication apparatus 501 and the ground apparatus B 511 move away, and the electric field intensity capable of wireless communication cannot be obtained (time 715). Here, the range from time 712 to time 715 is the range 693 shown in FIG.

  As will be described later, in order to compare the maximum value 701 and the maximum value 711, the beacon transmission interval between the ground device A 510 and the ground device B 511 is at least 1 from both time 703 to time 704 and from time 713 to time 714. The transmission interval is set for each time. Moreover, the irregular interval which can reproduce the graph shown in FIG. 7 may be sufficient.

  FIG. 8 is a diagram illustrating an example of a flowchart of determination processing for the direction and the traveling direction of the vehicle 500. This determination process corresponds to step 680 shown in FIG. 6 and is executed by the arithmetic unit 503. The arithmetic device 503 determines whether the combination of the ID of the ground device A 510 and the ID of the ground device B 511 recorded in steps 623 and 653 is an ID pair already registered in the ID pair table 506 (step 800). ).

  If there is a ground device other than the ground device A 510 and the ground device B 511, and a beacon transmitted by another ground device is received by interference, it is determined that the ID pair is unregistered, and the determination process is performed. The process ends (step 808). In the example of FIGS. 5 and 6, since the combination of the ID of the ground device A510 and the ID of the ground device B511 is a registered ID pair, it is determined that the ID pair is already registered, and the process proceeds to step 801.

  The arithmetic device 503 determines whether the ground device that has started communication with the communication device 501 is the ground device A 510 or the ground device B 511 (step 801). As shown in FIGS. 5 to 7, in this example, since the notification time regarding the ground device A 510 is recorded as the previous time in step 623, it is determined that the ground device A 510 has started the wireless communication first. Then, the process proceeds to step 802.

  The arithmetic device 503 compares the maximum value of the received radio wave intensity when each ground device performs wireless communication with the communication device 501 (step 802). As shown in FIG. 7, in this example, it is determined that the ground device B 511 is performing wireless communication with a higher received radio wave intensity, and the process proceeds to step 804. Then, it is determined that the vehicle 500 is “forward” and traveling in the “direction A520” (step 804), and the determination process is terminated (step 808).

  If the arithmetic device 503 determines in step 802 that the ground device A510 is performing wireless communication with a larger received radio wave intensity, the operation device 503 proceeds to step 803, and the vehicle 500 proceeds in the “reverse direction” to the “direction A520”. As a result of determination, the determination process is terminated (step 808).

  On the other hand, if it is determined in step 801 that the ground device B 511 has started wireless communication first, the arithmetic device 503 proceeds to step 805, and each ground device wirelessly communicates with the communication device 501 in the same manner as in step 802. Compare the maximum value of the received radio wave intensity when communicating.

  If the arithmetic device 503 determines in step 805 that the ground device A510 is performing wireless communication with a higher received radio wave intensity, the arithmetic device 503 proceeds to step 806, and the vehicle 100 proceeds “direction B521” in “forward”. As a result of determination, the determination process is terminated (step 808).

  If it is determined in step 805 that the ground device B511 is performing wireless communication with a higher received radio wave intensity in step 805, the arithmetic unit 503 proceeds to step 807, and the vehicle 500 is "reversed" in "direction B121". The determination process is terminated with the progress as a determination result (step 808).

  In the above description, the communication device 501 is installed on the left front side of the vehicle 500, the ground device A510 is installed on the right side in the direction A520 on the passage 530 and closer to the direction B521, and the ground device B511 is installed on the passage 530. Although the example in which the direction and the traveling direction of the vehicle 500 are determined in the case where the vehicle 500 is installed on the left side toward the upper direction A520 and closer to the direction A520 has been described, the present embodiment is not limited thereto.

  For example, the communication device 501 may be installed on the right side of the vehicle 500. Further, the ground device A510 is not limited to the center 531 on the passage 530, but may be installed so as to be biased leftward or rightward in the direction A520, and the ground device B511 is installed on the opposite side on the left and right sides of the ground device A510. It only has to be done. Further, either the ground device A510 or the ground device B511 may be installed closer to the direction A520.

  When the communication device 501 and each ground device are installed in this manner, the determination process similar to the determination process (step 680) of the direction and the traveling direction of the vehicle 500 is performed to thereby determine the direction and the traveling direction of the vehicle 500. Can be uniquely determined.

  In the above description, the first embodiment and the second embodiment have been described separately. However, the embodiments are not limited to independent ones. A part may be exchanged between each Example, and a part of Example may be added to another Example. Further, the passage 130 and the passage 530 may be combined, such that a part of the passage is the passage 130 including the ground device 110 and another part of the same passage is the passage 530 including the ground device A 510 and the ground device B 511. .

  Further, in the vehicle 100 provided with the communication device A101 and the communication device B102, either the communication device A101 or the communication device B102 is used as the communication device 501, the arithmetic device 103 has an ID pair table, and the determination process in step 680 is performed. May be executed. Further, in a vehicle in which a plurality of vehicles are connected, one or more vehicles may be the vehicle 100 or the vehicle 500.

100, 500: Vehicle 101: Communication device A
102: Communication device B
110: Ground device 130, 530: Passage 501: Communication device 510: Ground device A
511: Ground device B

Claims (12)

A vehicle state detection system including a vehicle and a ground device,
The ground device is
Send a beacon over the air,
The vehicle is
A plurality of communication devices each receiving a beacon and notifying each received radio wave intensity of the received beacon;
A calculation device that determines the direction and traveling direction of the vehicle based on the received radio wave intensity and the order notified from each of the plurality of communication devices ;
The vehicle is
Move along a path that has two directions,
The traveling direction of the vehicle is one of two directions of the passage,
The direction of the vehicle is either a front direction or a rear direction of the vehicle,
At least one of the plurality of communication devices is installed in a position that is biased to the front side of the vehicle and the first side of either of the left and right sides,
At least one other of the plurality of communication devices is installed at a position behind the vehicle and on a second side different from the left and right first sides,
The ground device is
The vehicle state detection system, wherein the vehicle state detection system is installed at a position biased to either the left or right of the passage with respect to one direction of the passage . The vehicle state detection system according to claim 1 ,
The ground device is
Send beacons periodically over the air,
Each of the plurality of communication devices is
Receives the beacon multiple times, notifies the received signal strength of the received beacon multiple times,
The arithmetic unit is:
A vehicle state detection system, wherein the received radio wave intensity and the notification time of a plurality of times notified from each of the plurality of communication devices are recorded, and the direction and the traveling direction of the vehicle are determined when no notification is received. The vehicle state detection system according to claim 2 ,
As the vehicle moves in the direction of travel, it approaches the ground device and passes the vicinity,
Each of the plurality of communication devices is
When the reception of the beacon is started, notification of the received radio wave intensity of the received beacon is started,
The arithmetic unit is:
The vehicle state detection system characterized by determining the direction of the vehicle based on the order in which the two communication devices start notification. The vehicle state detection system according to claim 3 ,
The arithmetic unit is:
A vehicle state detection system that determines a traveling direction of the vehicle based on a difference between maximum values of received radio wave intensities notified from the two communication devices. A vehicle state detection system including a vehicle and a plurality of ground devices,
Each of the plurality of ground devices is
Send a beacon over the air,
The vehicle is
A communication device that receives a plurality of beacons and notifies the received radio field strength of each received beacon;
An arithmetic device that determines the direction and traveling direction of the vehicle based on the received radio wave intensity and the order notified from the communication device , and
The vehicle is
Move along a path that has two directions,
The traveling direction of the vehicle is one of two directions of the passage,
The direction of the vehicle is either a front direction or a rear direction of the vehicle,
The communication device is installed at a position biased to either the left or right of the vehicle,
At least one of the plurality of the ground devices is installed at a first position that is biased to the first side of the left or right of the passage with respect to one direction of the passage,
At least one of the plurality of ground devices is
It is located in the 2nd position which is away from the 1st position to one direction of the passage, and is biased to the 2nd side different from the 1st right and left sides of the passage. Vehicle state detection system. The vehicle state detection system according to claim 5 ,
Each of the plurality of ground devices is
Send beacons periodically over the air,
The communication device
Receives the beacon multiple times, notifies the received signal strength of the received beacon multiple times,
The arithmetic unit is:
The vehicle state detection system characterized by recording the received radio wave intensity and the notification time of a plurality of times notified from the communication device, and determining the direction and the traveling direction of the vehicle when no notification is received. The vehicle state detection system according to claim 6 ,
At least two of the plurality of ground devices are
When the vehicle moves in the direction of travel, it is approached and passed nearby.
Periodically transmitting a beacon including identification information of each of the ground devices by radio waves,
The communication device
When reception of the beacon is started, notification of received radio wave intensity and identification information of the received beacon is started,
The arithmetic unit is:
A vehicle state detection system that determines a traveling direction of the vehicle based on an order in which notification of two different pieces of identification information is started. The vehicle state detection system according to claim 7 ,
The arithmetic unit is:
A vehicle state detection system that determines the direction of the vehicle based on a difference between maximum values of received radio wave intensities notified together with two different pieces of identification information. A vehicle for detecting a vehicle state,
A plurality of communication devices each receiving a beacon by radio wave and notifying the received radio wave intensity of the received beacon;
A calculation device that determines the direction and traveling direction of the vehicle based on the received radio wave intensity and the order notified from each of the plurality of communication devices ;
The vehicle is
Move along a path that has two directions,
The traveling direction of the vehicle is one of two directions of the passage,
The direction of the vehicle is either a front direction or a rear direction of the vehicle,
At least one of the plurality of communication devices is
It is installed in front of the vehicle and at a position biased to either the left or right first side,
At least one of the plurality of communication devices is installed at a position behind the vehicle and on a second side different from the left and right first sides . The vehicle according to claim 9 , wherein
Each of the plurality of communication devices is
Receives the beacon multiple times, notifies the received signal strength of the received beacon multiple times,
The arithmetic unit is:
A vehicle characterized in that the received radio wave intensity and the notification times of a plurality of times notified from each of the plurality of communication devices are recorded, and the direction and the traveling direction of the vehicle are determined when no notification is received. A vehicle according to claim 1 0,
The vehicle moves in the direction of travel passing close to the source of the beacon,
Each of the plurality of communication devices is
When the reception of the beacon is started, notification of the received radio wave intensity of the received beacon is started,
The arithmetic unit is:
A vehicle characterized in that the orientation of the vehicle is determined based on the order in which the two communication devices start notification. A vehicle according to claim 1 1,
The arithmetic unit is:
A vehicle, wherein a traveling direction of the vehicle is determined based on a difference between maximum values of received radio wave intensities notified from two communication devices.

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