JP2015222486A - Vehicle communication system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a vehicle communication system that detects a pedestrian around a vehicle and is able to perform prescribed control by using a simple and small out-vehicle mobile transmitter that generates power by pressure caused by walking of the pedestrian and transmits a prescribed walking signal by radio whenever the pedestrian walks.SOLUTION: A vehicle communication system comprises an on-vehicle device 1 and an out-vehicle mobile transmitter 5. The out-vehicle mobile transmitter 5 includes a piezoelectric unit for generating power by pressure caused by walking of a pedestrian, is driven by the power generated by the piezoelectric unit, and transmits a prescribed walking signal by radio whenever the pedestrian walks. The on-vehicle device 1 includes a reception unit for receiving the walking signal transmitted by the out-vehicle mobile transmitter 5 and outputs a control signal to control the operation of a warning device if the reception unit has received the walking signal.

Description

  The present invention relates to a vehicle communication system including an out-of-vehicle movement transmitter that wirelessly transmits a predetermined walking signal each time a pedestrian walks, and an in-vehicle device that receives a walking signal transmitted from the out-of-vehicle movement transmitter. .

  An inter-pedal communication system has been proposed in which a pedestrian terminal carried by a pedestrian communicates with an in-vehicle device mounted on the vehicle to notify the driver of the vehicle of the presence of a pedestrian at risk of collision ( For example, Non-Patent Document 1). The pedestrian terminal and the vehicle-mounted device constitute an ad hoc network that can be wirelessly connected without using a base station, a roadside device provided on the shoulder of the road, or the like. The pedestrian terminal includes a GPS receiver that detects the position of the pedestrian, a wireless communication unit that performs wireless communication with the vehicle-mounted device, a data processing unit, and the like. The pedestrian terminal transmits information such as the position of the pedestrian detected using the GPS receiver to the in-vehicle device using the wireless communication unit. The vehicle-mounted device receives the information transmitted from the pedestrian terminal and notifies the driver of the presence of a pedestrian who is at risk of collision.

Toshi Kaneko and Masaharu Hamaguchi, “Development of inter-vehicle communication system”, OKI Technical Review, October 2011, No. 218, Vol. 78 No. 1, p. 72-77

  However, in the pedestrian communication system according to Non-Patent Document 1, a special pedestrian terminal for wireless connection is prepared in an ad hoc network, and the pedestrian has a pedestrian terminal having a size comparable to that of a mobile phone terminal. There was a problem that had to be done. It is difficult for infants, children, and the like who have a high risk of jumping out on the road to always have such special pedestrian terminals, and it is difficult to disseminate the inter-pedal communication system to children to be protected.

  The present invention has been made in view of such circumstances, and uses a simple and small outside vehicle transmitter that generates electric power by pressure accompanying walking of a pedestrian and transmits a predetermined walking signal wirelessly every time when walking. Thus, a vehicle communication system capable of detecting a pedestrian existing around the vehicle and performing predetermined control is provided.

  A vehicular communication system according to the present invention is a vehicular communication system including an out-of-vehicle movement transmitter that wirelessly transmits a signal, and an in-vehicle device that receives a signal transmitted from the out-of-vehicle movement transmitter. The transmitter is driven by the piezoelectric unit that generates power by the pressure accompanying walking of the pedestrian and the electric power generated by the piezoelectric unit, and transmits a predetermined walking signal by radio every time the pedestrian walks. The vehicle-mounted device receives a walking signal transmitted from the walking signal transmission unit, and outputs a control signal for controlling the operation of the external device when the receiving unit receives the walking signal. And an output unit.

In the present invention, the piezoelectric part generates power by the pressure accompanying walking of the pedestrian, and the walking signal transmission part of the on-vehicle mobile transmitter is driven by the electric power generated by the piezoelectric part. The walking signal transmission unit transmits a predetermined walking signal each time the pedestrian walks, and the receiving unit of the in-vehicle device receives the walking signal transmitted from the walking signal transmission unit. Since the walking signal is transmitted in accordance with the pedestrian's pace, the vehicle-mounted device can obtain information on the pedestrian's pace from the received walking signal.
In addition, since the walking signal transmission unit is driven by the electric power generated by the pressure accompanying the walking of the pedestrian, the walking signal transmitted from the walking signal transmission unit is mounted on a vehicle around the pedestrian. Only reach the on-board machine. Therefore, the vehicle-mounted device can receive a walking signal transmitted from a pedestrian's outside vehicle transmitter that exists in the vicinity of the vehicle on which the vehicle-mounted device is mounted. The gait signal transmitted from is not received. That is, the vehicle-mounted device can selectively obtain information regarding the pedestrian's pace existing around the vehicle on which the vehicle-mounted device is mounted.
The output unit of the in-vehicle device outputs a control signal to the external device when the receiving unit receives the walking signal. Therefore, the vehicle-mounted device can control the external device according to the presence of the pedestrian.

  In the vehicular communication system according to the present invention, when the on-vehicle device receives a plurality of walking signals, the vehicle-mounted device includes a timing unit that measures the time when the plurality of walking signals are received, and the plurality of walking signals. A determination unit that determines whether or not a time interval for reception is less than a threshold, and the output unit outputs a control signal when the determination unit determines that the interval is less than the threshold.

  In the present invention, the in-vehicle device measures the time of the plurality of walking signals received by the receiving unit with the time measuring unit, and determines whether or not the time interval for receiving the plurality of walking signals is less than the threshold value. Determine by. When a pedestrian is running, the time interval for receiving a plurality of walking signals is shortened to be less than the threshold value. An output part outputs a control signal to an external device, when it determines with the time interval which receives a walk signal being less than a threshold value. Therefore, the in-vehicle device can control the external device when there is a running pedestrian, that is, a pedestrian who has a risk of suddenly jumping out on the road.

  In the vehicle communication system according to the present invention, the in-vehicle device includes a measurement unit that measures a received signal strength of a walking signal received by the receiving unit, and the output unit receives the walking signal received by the receiving unit and the walking signal. A control signal is output according to the received signal strength measured by the measurement unit.

  In the present invention, the in-vehicle device measures the received signal strength of a plurality of walking signals received by the receiving unit at the measuring unit, and the output unit outputs a control signal according to the measured received signal strength. The received signal strength of the walking signal varies depending on the distance between the vehicle on which the vehicle-mounted device is mounted and the pedestrian. Therefore, the in-vehicle device can control the external device according to the distance between the pedestrian and the vehicle.

  In the vehicle communication system according to the present invention, the in-vehicle device includes a measuring unit that measures a received signal strength of a walking signal received by the receiving unit, and each walking signal when the receiving unit receives a plurality of walking signals. And an increase determination unit that determines whether or not the received signal strength of the output is increased, the output unit determines that the determination unit is equal to or greater than a threshold value, and determines that the increase determination unit is increasing If so, a control signal is output.

In the present invention, the in-vehicle device measures the time of the plurality of walking signals received by the receiving unit with the time measuring unit, and determines whether or not the time interval for receiving the plurality of walking signals is less than the threshold value. Judgment by. In addition, the in-vehicle device measures the reception signal strength of the plurality of walking signals received by the receiving unit, and determines whether or not the plurality of walking signals are increasing. When a pedestrian is approaching a vehicle on which an in-vehicle device is mounted, the walking signal increases. The output unit outputs the control signal to the external device when it is determined that the time interval for receiving the walking signal is less than the threshold and the received signal strength of the walking signal is increasing.
Therefore, the vehicle-mounted device can control the external device when a running pedestrian is approaching the vehicle.

  The vehicle communication system according to the present invention includes a warning device that warns of the presence of the pedestrian, and the output unit outputs a control signal that controls the operation of the warning device.

  In the present invention, the vehicle-mounted device warns the vehicle driver of the presence of a pedestrian by controlling the warning device.

  In the vehicle communication system according to the present invention, the piezoelectric unit and the walking signal transmission unit are provided in the shoes of the pedestrian.

In the present invention, the piezoelectric unit and the walking signal transmission unit are provided in a pedestrian shoe. Therefore, pressure is applied to the piezoelectric portion every time walking. The vehicle-mounted device can transmit a walking signal each time a pedestrian walks.
In addition, since the piezoelectric part and the walking signal transmission part are provided in the shoes, it is possible to effectively prevent a pedestrian from forgetting to carry the outside-vehicle movement transmitter.

  A vehicle communication system according to the present invention receives a signal transmitted from a plurality of antennas provided in a vehicle, a signal transmitted from the transmitter, and transmits a response signal corresponding to the received signal. A reception device that receives a response signal transmitted from the portable device, and further locks or unlocks the vehicle door according to the response signal received by the reception unit. The control part which performs the process which concerns is provided.

  In the present invention, a so-called smart entry (registered trademark) system is configured by the transmission unit, the reception unit, and the portable device. The walking signal can be received by the receiving unit constituting the smart entry system, and the manufacturing cost of the vehicle communication system can be suppressed.

  According to the present invention, a pedestrian that exists in the vicinity of a vehicle by using a simple and small outside mobile transmitter that generates electric power by pressure accompanying walking of the pedestrian and transmits a predetermined walking signal by radio every time the walking is performed. Can be detected and predetermined control can be performed.

1 is a conceptual diagram illustrating a configuration example of a vehicle communication system according to a first embodiment. It is a block diagram which shows the example of 1 structure of the exterior mobile transmitter which concerns on Embodiment 1. FIG. It is a block diagram which shows one structural example of the vehicle equipment which concerns on Embodiment 1. FIG. 3 is a flowchart illustrating a processing procedure of a control unit according to the first embodiment. It is a block diagram which shows one structural example of the vehicle equipment which concerns on Embodiment 2. FIG. 10 is a flowchart illustrating a processing procedure of a control unit according to the second embodiment.

Hereinafter, the present invention will be described in detail with reference to the drawings illustrating embodiments thereof. Note that the embodiments described below and various modifications may be arbitrarily combined.
(Embodiment 1)
FIG. 1 is a conceptual diagram illustrating a configuration example of a vehicle communication system according to the first embodiment. The vehicle communication system according to the first embodiment transmits signals between the in-vehicle device 1 that transmits and receives various signals using the plurality of transmission antennas 3 and reception antennas 4 provided in the vehicle C, and the in-vehicle device 1. It comprises a portable device 2 that transmits and receives, and constitutes a so-called smart entry system. The plurality of transmission antennas 3 are provided, for example, at the driver side pillar, the passenger side pillar, the back door, and the front portion of the vehicle C. The receiving antenna 4 is provided at an appropriate location of the vehicle C.
The in-vehicle device 1 transmits a signal for determining the position of the portable device 2 from a plurality of transmission antennas 3 using radio waves in an LF (Low Frequency) band. The portable device 2 receives the signal transmitted from each transmission antenna 3 and measures the received signal strength of each received signal. The portable device 2 transmits a response signal including the measured received signal strength to the in-vehicle device 1 using a radio wave in the UHF (Ultra High Frequency) band. The in-vehicle device 1 receives the response signal transmitted from the portable device 2, determines whether the portable device 2 is inside or outside the vehicle based on the received signal strength included in the received response signal, and executes predetermined processing according to the determination result To do. For example, the in-vehicle device 1 executes processing such as locking or unlocking of a vehicle door, starting of an engine, warning of forgetting to lock the vehicle door, and the like.

  The vehicular communication system is provided on the shoe sole of the pedestrian, and includes an out-of-vehicle movement transmitter 5 that wirelessly transmits a walking signal each time the user walks. The in-vehicle device 1 receives the walking signal transmitted from the outside vehicle transmitter 5, detects a pedestrian at risk of collision based on the walking signal, and executes a predetermined process according to the detection result. For example, a process for warning the driver of the vehicle C of the presence of a pedestrian is executed.

  FIG. 2 is a block diagram showing an example of the configuration of the external vehicle transmitter 5 according to the first embodiment. The out-of-vehicle movement transmitter 5 is provided in the heel part B of the shoe A worn by a pedestrian. The off-vehicle movement transmitter 5 includes a piezoelectric unit 50 that generates electric power by pressure accompanying walking of a pedestrian, and a control unit 51 and a walking signal transmission unit 52 that are driven by electric power generated by the piezoelectric unit 50.

  The piezoelectric part 50 is a piezoelectric element buried in the heel part B of the shoe A. The piezoelectric element has a structure in which a piezoelectric material such as ceramics or quartz crystal that generates a voltage by deformation due to external pressure is sandwiched between two electrodes, and the generated electric power is supplied to the control unit 51 and the walking signal transmission unit 52. A white arrow indicates power supplied from the piezoelectric unit 50 to the control unit 51 and the walking signal transmission unit 52. In FIG. 2, the electric power generated by the piezoelectric unit 50 is directly supplied to the control unit 51 and the walking signal transmission unit 52. However, the voltage is stabilized and supplied by the stabilization circuit. May be.

  The control unit 51 is a microcomputer having, for example, a CPU (Central Processing Unit), a ROM (Read Only Memory), a RAM (Random Access Memory), and the like. The control unit 51 is driven by the electric power supplied from the piezoelectric unit 50. The activated control unit 51 controls the operation of each component unit by executing a control program stored in the ROM. Specifically, the activated control unit 51 gives predetermined information to the walking signal transmission unit 52 and wirelessly transmits a walking signal including the information. Each time the pedestrian walks, the control unit 51 is activated by being supplied with electric power, and gives the predetermined information to the walking signal transmission unit 52. It is sufficient that the walking signal has predetermined information that can be identified as a signal transmitted from the vehicle outside transmitter 5 provided in the pedestrian's shoes A. In addition to the predetermined information, identification information unique to the off-vehicle movement transmitter 5 may be included in the walking signal.

  The gait signal transmission unit 52 is driven by power supplied every time a pedestrian walks, modulates a carrier wave using information given from the control unit 51, and uses the antenna 52a to modulate the modulated gait signal. Send by radio. The frequency band and modulation method of the signal transmitted by the walking signal transmission unit 52 are the same as the frequency band and modulation method of the signal transmitted by the portable device 2 constituting the smart entry system. For example, the walking signal transmission unit 52 transmits a walking signal modulated by the frequency shift keying method using radio waves in a UHF (Ultra High Frequency) band of 300 MHz to 3 GHz. Note that the frequency band and modulation scheme are examples.

  FIG. 3 is a block diagram illustrating a configuration example of the vehicle-mounted device 1 according to the first embodiment. The in-vehicle device 1 includes a control unit 11 that controls the operation of each component of the in-vehicle device 1. The control unit 11 includes a receiving unit 12, a transmitting unit 13, a time measuring unit 14, an input unit 15, and an output unit 16.

  The control unit 11 is a microcomputer having, for example, one or a plurality of CPUs, a multi-core CPU, a ROM, a RAM, and the like. The control unit 11 is connected to a receiving unit 12, a transmitting unit 13, a time measuring unit 14, an input unit 15, and an output unit 16. The control part 11 controls the operation | movement of each structure part by running the control program memorize | stored in ROM, and performs a pedestrian detection and a warning process. Moreover, the control part 11 performs the predetermined process according to the vehicle inside / outside determination of the portable device 2 and the vehicle inside / outside determination.

A receiving antenna 4 is connected to the receiving unit 12. The receiving unit 12 is a circuit that receives the walking signal transmitted from the vehicle-mounted mobile transmitter 5 by the receiving antenna 4. The receiving unit 12 demodulates the received walking signal and outputs information obtained by the demodulation to the control unit 11.
The receiving unit 12 receives the response signal transmitted from the portable device 2 by the receiving antenna 4. The receiving unit 12 demodulates the received response signal and outputs information obtained by the demodulation to the control unit 11.

  A plurality of transmission antennas 3 are connected to the transmission unit 13. The transmission unit 13 is a circuit that transmits signals from the plurality of transmission antennas 3 provided in the vehicle C to the portable device 2. The transmission unit 13 modulates a carrier wave (LF wave) of 30 kHz to 300 MHz based on the signal output from the control unit 11. The modulated signals are sequentially transmitted from the plurality of transmission antennas 3 individually.

  The timekeeping unit 14 measures the time when the reception unit 12 receives a plurality of walking signals, and provides the timekeeping result to the control unit 11. For example, the timekeeping unit 14 measures time intervals for receiving a plurality of walking signals, and gives the timed time intervals to the control unit 11. Moreover, the time measuring unit 14 may time points at which a plurality of walking signals are received, and give the time points at which the respective walking signals are received to the control unit 11. The control unit 11 calculates the reception period of the walking signal based on the timing result of the timing unit 14.

  The input unit 15 receives a request signal corresponding to the operation state of a vehicle door request switch (not shown), and the control unit 11 recognizes the operation state of the vehicle door request switch based on the request signal input via the input unit 15. can do. The vehicle door request switch is, for example, a switch for locking or unlocking a vehicle door on the driver's seat side or the passenger seat side, and is provided on a door handle outside the driver seat or outside the passenger seat. In place of the push button, a contact sensor for detecting the contact of the user's hand with the door handle may be provided. Moreover, the control part 11 may acquire directly the request signal corresponding to operation of a vehicle door request switch, and may acquire via door ECU (Electronic Control Unit), other ECU, etc. FIG.

The output unit 16 is connected to a warning device 6 that warns the driver of the vehicle C of the presence of a pedestrian. The control unit 11 outputs a control signal for controlling the operation of the warning device 6 to the warning device 6 via the output unit 16 according to the reception result of the walking signal. The warning device 6 issues a warning according to the control signal output from the control unit 11. The warning device 6 includes a speaker that outputs sound, a warning light, and the like, and issues a warning by sound or light.
In addition, the control unit 11 outputs a vehicle door control signal for controlling the unlocking or locking of the vehicle door according to the operation state of the vehicle door request switch and the situation that the portable device 2 is in the vehicle. Output to a door ECU (not shown) via the output unit 16. The door ECU locks or unlocks the vehicle door according to the vehicle door control signal from the control unit 11.

  A portable device 2 shown in FIG. 1 includes a control unit (not shown), and a portable reception unit, a portable transmission unit, and the like are connected to the control unit. The portable receiving unit receives a wireless signal transmitted from the in-vehicle device 1 with a three-axis antenna, and gives the received signal to the control unit. Further, the mobile receiver measures the received signal strength of the received signal, and the control unit transmits information on the received signal strength to the in-vehicle device 1 by the mobile transmitter. The portable transmission unit modulates the UHF band carrier wave based on the received signal strength information, and transmits the modulated response signal from the antenna.

  FIG. 4 is a flowchart illustrating a processing procedure of the control unit 11 according to the first embodiment. The control part 11 of the vehicle equipment 1 receives a signal in the receiving part 12 (step S11), and determines whether the received signal is a walking signal (step S12). When it determines with it being a walk signal (step S12: YES), the control part 11 time-measures the time which received the walk signal in the time measuring part 14, and memorize | stores it temporarily (step S13). Next, when the receiving unit 12 receives a plurality of walking signals, the control unit 11 calculates a walking cycle based on the temporarily stored time (step S14). Specifically, the control unit 11 calculates an average value of periods for receiving a plurality of walking signals. For example, when the walking signal is received 10 times in 10 seconds, the cycle is 1 [second]. When the walking signal is received 20 times in 10 seconds, it is 0.5 [seconds].

  Next, the control unit 11 determines whether or not the calculated walking cycle is less than a threshold value (step S15). When it determines with it being more than a threshold value (step S15: NO), the control part 11 finishes a process. The threshold is a numerical value for determining whether or not a pedestrian is running. When it is equal to or greater than the threshold, the pedestrian is walking slowly and there is no possibility that the pedestrian suddenly jumps out on the road.

  When it determines with it being less than a threshold value (step S15: YES), the control part 11 outputs a control signal to the warning device 6 (step S16), and complete | finishes a process. Upon receiving the control signal, the warning device 6 warns the driver of the presence of a pedestrian, in particular, the presence of a running pedestrian.

  If it is determined in step S12 that the received signal is not a walking signal (step S12: NO), the control unit 11 determines whether the received signal is a response signal from the portable device 2 (step S17). ). When it determines with it not being a response signal from the portable device 2 (step S17: NO), the control part 11 finishes a process. When it determines with it being a response signal from the portable device 2 (step S17: YES), the predetermined process based on a response signal is performed (step S18), and a process is complete | finished. For example, when receiving a response signal to the signal transmitted from the in-vehicle device 1 to the portable device 2 when operating the vehicle door request switch, the control unit 11 determines whether the portable device 2 is inside the vehicle and is outside the vehicle. If it is determined, processing related to locking or unlocking the vehicle door is executed. Further, when receiving a response signal to the signal transmitted from the in-vehicle device 1 to the portable device 2 to confirm the presence of the portable device 2 during engine operation, the control unit 11 determines whether the portable device 2 is in the vehicle. If there is no portable device 2 in the vehicle, a warning process is executed. Furthermore, when the response signal transmitted from the portable device 2 is received with respect to the signal transmitted from the in-vehicle device 1 to the portable device 2 when the engine switch is operated, the control unit 11 indicates that the portable device 2 is in the vehicle. If it is determined that the vehicle is in the vehicle, processing such as starting the engine is executed.

According to the vehicle communication system configured as described above, a simple and small outside vehicle transmitter 5 that generates electric power by pressure accompanying walking of a pedestrian and transmits a predetermined walking signal wirelessly every time the user walks is used. Thus, a pedestrian existing around the vehicle C can be detected and predetermined control can be performed.
In addition, when the vehicle C is stopped, that is, when the power supply to the vehicle-mounted device 1 is stopped, the receiving unit 12 of the vehicle-mounted device 1 receives signals intermittently, and there is a concern that the walking signal may be missed. However, the vehicle C is not a problem because it cannot travel. When the vehicle C is operating, the vehicle-mounted device 1 is activated, and the receiving unit 12 is in a state where signals can be received at all times. Therefore, when the vehicle C is in a state where it can travel, the vehicle-mounted device 1 can reliably detect a pedestrian running and issue a warning.
In addition, since the vehicle outside transmitter 5 is driven by the electric power of the piezoelectric unit 50, when a pedestrian is not walking, information on the pedestrian is not transmitted to the vehicle-mounted device 1, but when the pedestrian is not walking, The possibility that a pedestrian collides with the vehicle C is low and is not a problem.

  According to the first embodiment, in particular, a pedestrian that is running can be detected, and the warning device 6 can issue a warning to the driver.

  Moreover, since the vehicle outside transmitter 5 is provided in the pedestrian's shoes A, it is possible to effectively prevent the pedestrian from forgetting to carry the vehicle outside transmitter 5.

  Furthermore, in this Embodiment 1, since it has comprised so that the signal from the vehicle outside transmitter 5 may be received using the receiving part 12 which comprises a smart entry system, manufacture of the communication system for vehicles which concerns on this invention Cost can be reduced.

  In the first embodiment, an example in which a warning is issued to the driver by the warning device 6 when a pedestrian is detected has been described, but processing other than the warning to the driver may be executed. For example, the vehicle-mounted device 1 may be configured to output a control signal to the engine ECU and reduce the speed of the vehicle C when detecting a pedestrian running. Moreover, you may comprise so that a warning may be issued with respect to the pedestrian outside a vehicle. Furthermore, the vehicle C may be decelerated by controlling the operation of the brake when a pedestrian is detected. The process executed when the pedestrian is detected includes an arbitrary process for avoiding the pedestrian from colliding with the vehicle C.

  Moreover, although the vehicle outside transmitter 5 of this Embodiment 1 is provided in the pedestrian's shoes A, if the place where pressure is added with a pedestrian's walk, the vehicle outside transmitter 5 is set in another place. It may be provided. Moreover, as long as sufficient electric power can be obtained by the vertical vibration accompanying walking, a configuration in which the pedestrian carries the vehicle-mounted mobile transmitter 5 by an arbitrary method may be used.

Further, in the first embodiment, the example in which the vehicle outside transmitter is provided in one of the right shoe and the left shoe has been described, but the vehicle outside transmitter may be provided in both the right shoe and the left shoe. Moreover, although the example which comprises the vehicle communication system by the vehicle outside transmission device provided in one pair of shoes and vehicle equipment was demonstrated, the vehicle communication system by several sets of vehicle movement transmitters and vehicle equipment. May be configured. The configurations of the external vehicle transmitter and the in-vehicle device are the same as those of the first embodiment described above.
Although it is not necessary to identify the signals from the external vehicle transmitters provided in each of the shoes, each of the multiple external vehicle transmitters may be configured to transmit a walking signal including its own identification information. good. The in-vehicle device may calculate the walking cycle for each of the plurality of out-of-vehicle movement transmitters based on the identification information included in the walking signal, and determine whether the walking cycle is less than the threshold value. In this case, a running pedestrian can be individually detected and a warning can be issued.

  Furthermore, in the first embodiment, an example in which the receiving unit 12 is also used as a smart entry system has been described. However, a dedicated receiver that receives a walking signal transmitted from the vehicle-mounted moving transmitter 5 may be provided.

(Embodiment 2)
The vehicle communication system according to the second embodiment issues a warning to the driver when a pedestrian is running and approaching the vehicle C. The vehicle communication system according to the second embodiment includes an in-vehicle device 201, a portable device 2, and an out-of-vehicle mobile transmitter 5 similar to those in the first embodiment. Since the vehicle communication system according to the second embodiment is different in configuration and processing procedure of the in-vehicle device 201, the following mainly describes the differences. Since other configurations and operational effects are the same as those of the first embodiment, the corresponding portions are denoted by the same reference numerals, and detailed description thereof is omitted.

  FIG. 5 is a block diagram illustrating a configuration example of the vehicle-mounted device 201 according to the second embodiment. Similarly to the first embodiment, the in-vehicle device 201 according to the second embodiment includes a control unit 11, a reception unit 212, a transmission unit 13, a time measuring unit 14, an input unit 15, and an output unit 16. The receiving unit 212 according to the second embodiment includes a measuring unit 212a that measures the received signal strength of the received walking signal, that is, the electric field strength of the walking signal.

  FIG. 6 is a flowchart illustrating a processing procedure of the control unit 11 according to the second embodiment. The control unit 11 of the in-vehicle device 201 receives the signal at the reception unit 212 (step S211), and determines whether or not the received signal is a walking signal (step S212). When it determines with it being a walk signal (step S212: YES), the control part 11 measures the received signal strength of the walk signal received in the receiving part 212 in the measurement part 212a, and measures the received signal strength measured temporarily. Store (step S213). More specifically, the measuring unit 212 a measures the received signal strength of the walking signal received by the receiving unit 212 and outputs the measured received signal strength to the control unit 11. The control unit 11 acquires the received signal strength output from the measurement unit 212a.

  And the control part 11 time-measures the time which received the walk signal in the time measuring part 14, and memorize | stores it temporarily (step S214). Next, when the reception unit 212 receives a plurality of walking signals, the control unit 11 calculates a walking cycle based on the temporarily stored time (step S215).

  Next, the control unit 11 determines whether or not the calculated walking cycle is less than a threshold value (step S216). When it determines with it being more than a threshold value (step S216: NO), the control part 11 finishes a process.

  When it determines with it being less than a threshold value (step S216: YES), the control part 11 determines whether the received signal strength of the several walk signal which the receiving part 212 received has increased (step S217). That is, the control unit 11 determines whether or not the received signal strength of the walking signal received later is larger than the received signal strength of the previously received walking signal. Note that the received signal strength does not necessarily have to increase continuously. For example, it is sufficient that the moving average of the received signal strength increases.

  If it is determined that the received signal strength has not increased (step S217: NO), the control unit 11 ends the process. When the received signal strength is not increased, the pedestrian is moving away from the vehicle C even if the pedestrian is running, and the risk that the pedestrian collides with the vehicle C is low.

  If it is determined that the received signal strength is increasing (step S217: YES), the control unit 11 outputs a control signal to the warning device 6 (step S218), and the process ends. The warning device 6 that has received the control signal warns the driver of the presence of a pedestrian, particularly the presence of a pedestrian running in a direction approaching the vehicle C.

  In Step S212, when it is determined that the received signal is not a walking signal (Step S212: NO), the control unit 11 performs the same processing as Step S17 and Step S18 in Embodiment 1 in Step S219 and Step S220. And finish the process. Since the processing content is the same as that of Embodiment 1, detailed description is abbreviate | omitted.

  According to the vehicle communication system according to the second embodiment, a pedestrian running in a direction approaching the vehicle C can be detected and a warning can be issued to the driver.

(Modification)
In the second embodiment, the example in which the pedestrian is detected using both the walking cycle and the received signal strength of the walking signal has been described, but the walking cycle is not calculated and the received signal strength of the walking signal is increased. It may be configured to determine only whether or not and issue a warning. That is, you may comprise so that the process of step S214-step S216 shown in FIG. 6 may not be performed.
According to the modification, it is possible to detect a pedestrian approaching the vehicle C and issue a warning to the driver regardless of whether or not the pedestrian is running.

  The embodiment disclosed this time is to be considered as illustrative in all points and not restrictive. The scope of the present invention is defined by the terms of the claims, rather than the meanings described above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

DESCRIPTION OF SYMBOLS 1,201 In-vehicle machine 2 Portable machine 3 Transmitting antenna 4 Receiving antenna 5 Outside vehicle transmitter 6 Warning device 11 Control part 12,212 Receiving part 13 Transmitting part 14 Timing part 15 Input part 16 Output part 50 Piezoelectric part 51 Control part 52 Walking Signal transmission part 212a Measuring part A Shoes B Bag part C Vehicle

Claims (7)

A vehicle communication system comprising an out-of-vehicle mobile transmitter that wirelessly transmits a signal and an in-vehicle device that receives a signal transmitted from the out-of-vehicle mobile transmitter,
The off-vehicle movement transmitter is
A piezoelectric part that generates electricity by the pressure accompanying walking of the pedestrian,
A driving signal transmission unit that is driven by the electric power generated by the piezoelectric unit and transmits a predetermined walking signal wirelessly each time the pedestrian walks;
The in-vehicle device is
A receiving unit for receiving a walking signal transmitted from the walking signal transmitting unit;
A vehicle communication system comprising: an output unit that outputs a control signal for controlling the operation of an external device when the receiving unit receives a walking signal. The in-vehicle device is
When the receiving unit has received a plurality of walking signals, a time measuring unit for measuring the time of receiving the plurality of walking signals;
A determination unit that determines whether a time interval for receiving the plurality of walking signals is less than a threshold value, and
The output unit is
The vehicle communication system according to claim 1, wherein a control signal is output when the determination unit determines that the value is less than a threshold value. The in-vehicle device is
A measuring unit for measuring the received signal strength of the walking signal received by the receiving unit;
The output unit is
The vehicle communication system according to claim 1 or 2, wherein a control signal is output according to a walking signal received by the receiving unit and a received signal intensity measured by the measuring unit. The in-vehicle device is
A measuring unit for measuring the received signal strength of the walking signal received by the receiving unit;
An increase determination unit that determines whether or not the received signal strength of each walking signal is increased when the receiving unit receives a plurality of walking signals;
The output unit is
The vehicle communication system according to claim 2, wherein when the determination unit determines that the value is greater than or equal to a threshold and the increase determination unit determines that the increase is occurring, a control signal is output. Comprising a warning device for warning the presence of the pedestrian,
The output unit is
The vehicle communication system according to any one of claims 1 to 4, wherein a control signal for controlling an operation of the warning device is output. The vehicular communication system according to any one of claims 1 to 5, wherein the piezoelectric unit and the walking signal transmission unit are provided in shoes of the pedestrian. A transmitter for transmitting signals from a plurality of antennas provided in the vehicle;
A portable device that receives a signal transmitted from the transmission unit and transmits a response signal corresponding to the received signal;
The receiving unit is adapted to receive a response signal transmitted from the portable device;
Furthermore,
The vehicle communication system according to any one of claims 1 to 6, further comprising a control unit that executes a process related to locking or unlocking the vehicle door in accordance with a response signal received by the receiving unit. .

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