Pedestrian-vehicle communication system, in-vehicle terminal device, pedestrian terminal device and safe-driving assistance method

In order to enable a driver in driving a vehicle to quickly and assuredly recognize a pedestrian having a collision risk with the vehicle even when it is difficult for the driver to recognize the pedestrian by eyes, such as during night time, an in-vehicle terminal device is configured to: determine a collision risk based on pedestrian position information and vehicle position information; generate turn-on instruction information which, when the pedestrian is determined to have the collision risk with the vehicle, causes an indicator light carried by the pedestrian to be turned on in a prescribed light color; and transmit the turn-on instruction information to a pedestrian terminal device via pedestrian-vehicle communication, and wherein the pedestrian terminal device is configured to: receive the turn-on instruction information transmitted from the in-vehicle terminal device; and turn on the indicator light based on the turn-on instruction information.

TECHNICAL FIELD

The present invention relates to a pedestrian-vehicle communication system comprising an in-vehicle terminal device mounted on a vehicle and a pedestrian terminal device carried by a pedestrian, wherein pedestrian position information and vehicle position information are transmitted and received between the in-vehicle terminal device and the pedestrian terminal device via pedestrian-vehicle communication. The present invention also relates to an in-vehicle terminal device, a pedestrian terminal device, and a safe-driving assistance method for assisting a driver in driving a vehicle by performing pedestrian-vehicle communication.

BACKGROUND ART

In recent years, studies have been in progress for the practical and widespread use of safe driver assistance wireless systems by utilizing ITS (Intelligent Transport System). In such safe driver assistance wireless systems, in order to alert drivers in vehicles to avoid accidents, vehicle position information and other information are transmitted and received between two or more in-vehicle terminal devices mounted on vehicles via vehicle-vehicle communication and are also transmitted and received between roadside devices provided in roadside and in-vehicle terminal devices via roadside-vehicle communication.

In recent years, pedestrian-vehicle communication technologies have been presented in which a pedestrian terminal device carried by a pedestrian communicates directly with in-vehicle terminal devices in order to prevent pedestrian accidents. Since, in this pedestrian-vehicle communication, direct communication between a pedestrian terminal device and an in-vehicle terminal device enables alerts to be provided to both the pedestrian and the vehicle drivers at an appropriate time, this technology is expected to significantly prevent traffic accidents involving pedestrians.

In such a pedestrian-vehicle communication, pedestrian information including pedestrian position information is transmitted from a pedestrian terminal device carried by a pedestrian to an in-vehicle terminal device mounted on a vehicle, and upon receiving the pedestrian information, the in-vehicle terminal device makes a collision determination to determine whether or not the own vehicle has a high collision risk with the pedestrian; that is, whether or not the own vehicle is highly likely to collide with the pedestrian, and provides an alert to the driver in the vehicle when it is determined necessary from the result of the collision determination.

Generally, in order to alert a driver, a warning sound or a warning voice announcement is produced or a warning image is displayed on a display device. However, such an alert alone is not sufficient for a driver to instantly grasp where a pedestrian with a high collision risk is located and which pedestrian around the driver's vehicle has a collision risk. Thus, there is a need to indicate the presence of a pedestrian with a significant collision risk on a display screen.

Such prior art technologies concerning the notification to a driver of the presence of a pedestrian with a collision risk include a pedestrian detection system including an in-vehicle display device configured to produce a map on which the locations of pedestrians are indicated with marks having different colors or shapes which are determined depending on the degree of risk (See Patent Document 1). Known technologies further include a device configured to notify a driver of the presence of a pedestrian with a collision risk by displaying an alert image projected on a windshield or using other display methods (See Patent Document 2).

PRIOR ART DOCUMENT (S)

SUMMARY OF THE INVENTION

Task to be Accomplished by the Invention

However, there is a problem that, during night time, it becomes difficult to recognize pedestrians by eyes and thus, even when a display device displays the location of a pedestrian having a high collision risk, a driver cannot instantly grasp where the actual pedestrian is located and it takes some time for the driver to grasp the location of the pedestrian.

The present invention has been made in view of such problems of the prior art, and a primary object of the present invention is to provide a pedestrian-vehicle communication system, an in-vehicle terminal device, and an safe-driving assistance method, which enable a driver to quickly and assuredly recognize a pedestrian having a collision risk even in a situation in which drivers cannot easily recognize pedestrians by eyes, such as during night time.

Means to Accomplish the Task

An aspect of the present invention provides a pedestrian-vehicle communication system comprising an in-vehicle terminal device mounted on a vehicle and a pedestrian terminal device carried by a pedestrian, wherein pedestrian position information and vehicle position information are transmitted and received between the in-vehicle terminal device and the pedestrian terminal device via pedestrian-vehicle communication, wherein the in-vehicle terminal device comprises: a collision determiner configured to determine a collision risk based on the pedestrian position information and the vehicle position information; a turn-on instruction generator configured to generate turn-on instruction information which, when the collision determiner determines that the pedestrian has the collision risk, causes an indicator light carried by the pedestrian to be turned on in a prescribed light color; and a pedestrian-vehicle communicator configured to transmit the turn-on instruction information to the pedestrian terminal device via the pedestrian-vehicle communication; and wherein the pedestrian terminal device comprises: a pedestrian-vehicle communicator configured to receive the turn-on instruction information transmitted from the in-vehicle terminal device; and a turn-on controller configured to turn on the indicator light based on the turn-on instruction information.

Another aspect of the present invention provides an in-vehicle terminal device mounted on a vehicle for performing pedestrian-vehicle communication with a pedestrian terminal device carried by a pedestrian, wherein pedestrian position information and vehicle position information are transmitted and received between the in-vehicle terminal device and the pedestrian terminal device via the pedestrian-vehicle communication, comprising: a collision determiner configured to determine a collision risk based on the pedestrian position information and the vehicle position information; a turn-on instruction generator configured to generate turn-on instruction information which, when the collision determiner determines that the pedestrian has the collision risk, causes an indicator light carried by the pedestrian to be turned on in a prescribed light color; and a pedestrian-vehicle communicator configured to transmit the turn-on instruction information to the pedestrian terminal device via the pedestrian-vehicle communication.

Another aspect of the present invention provides a pedestrian terminal device carried by a pedestrian for performing pedestrian-vehicle communication with an in-vehicle terminal device mounted on a vehicle, wherein pedestrian position information and vehicle position information are transmitted and received between the in-vehicle terminal device and the pedestrian terminal device via the pedestrian-vehicle communication, comprising: a short range communicator configured to perform communication with an indicator light carried by the pedestrian; a pedestrian-vehicle communicator configured to receive turn-on instruction information from the in-vehicle terminal device, the turn-on instruction information causing the indicator light carried by the pedestrian to be turned on in a prescribed light color; and a turn-on controller to turn on the indicator light by the short range communicator based on the turn-on instruction information.

Yet another aspect of the present invention provides a safe-driving assistance method for assisting a driver in driving a vehicle by performing pedestrian-vehicle communication through which pedestrian position information and vehicle position information are transmitted and received between an in-vehicle terminal device mounted on the vehicle and a pedestrian terminal device carried by a pedestrian, wherein the in-vehicle terminal device: determines a collision risk based on the pedestrian position information and the vehicle position information; generates turn-on instruction information which, when the collision determiner determines that the pedestrian has the collision risk, causes an indicator light carried by the pedestrian to be turned on in a prescribed light color; and transmits the turn-on instruction information to the pedestrian terminal device via the pedestrian-vehicle communication; and wherein the pedestrian terminal device: receives the turn-on instruction information transmitted from the in-vehicle terminal device; and turns on the indicator light based on the turn-on instruction information.

Effect of the Invention

According to the present invention, since an indicator light carried by a pedestrian having a collision risk is turned on, a driver can quickly and assuredly recognize such pedestrians having collision risks.

DESCRIPTION OF THE PREFERRED EMBODIMENT(S)

A first aspect of the present invention made to achieve the above-described object is a pedestrian-vehicle communication system comprising an in-vehicle terminal device mounted on a vehicle and a pedestrian terminal device carried by a pedestrian, wherein pedestrian position information and vehicle position information are transmitted and received between the in-vehicle terminal device and the pedestrian terminal device via pedestrian-vehicle communication, wherein the in-vehicle terminal device comprises: a collision determiner configured to determine a collision risk based on the pedestrian position information and the vehicle position information; a turn-on instruction generator configured to generate turn-on instruction information which, when the collision determiner determines that the pedestrian has the collision risk, causes an indicator light carried by the pedestrian to be turned on in a prescribed light color; and a pedestrian-vehicle communicator configured to transmit the turn-on instruction information to the pedestrian terminal device via the pedestrian-vehicle communication; and wherein the pedestrian terminal device comprises: a pedestrian-vehicle communicator configured to receive the turn-on instruction information transmitted from the in-vehicle terminal device; and a turn-on controller configured to turn on the indicator light based on the turn-on instruction information.

According to the first aspect of the present invention, since the indicator light carried by the pedestrian having a collision risk is turned on, the driver can quickly and assuredly recognize such pedestrians having collision risks.

A second aspect of the present invention is the pedestrian-vehicle communication system according to the first aspect, wherein the turn-on instruction generator of the in-vehicle terminal device generates the turn-on instruction information which causes the indicator light to be turned on in a light color specific to the vehicle on which the in-vehicle terminal device is mounted.

According to the second aspect of the present invention, the driver can quickly recognize a pedestrian having a collision risk with the own vehicle.

A third aspect of the present invention is the pedestrian-vehicle communication system according to the second aspect, wherein, upon receiving the turn-on instruction information from a plurality of in-vehicle terminal devices, the turn-on controller of the pedestrian terminal device causes the indicator light to be turned on based on the turn-on instruction information which is transmitted from the in-vehicle terminal device of the vehicle having a highest collision risk.

According to the third aspect of the present invention, since the light color is set based on the turn-on instruction information chosen with priority given to the information from the in-vehicle terminal device of the vehicle having the highest collision risk, the driver of the vehicle having the highest collision risk can quickly recognize a pedestrian having a collision risk with the own vehicle.

A fourth aspect of the present invention is the pedestrian-vehicle communication system according to the first aspect, wherein, when there are a plurality of pedestrians having collision risks with the vehicle, the turn-on instruction generator of the in-vehicle terminal device generates the turn-on instruction information which causes the plurality of indicator lights to be turned on in respective different light colors.

According to the fourth aspect of the present invention, since the lights of the pedestrians have different light colors assigned, a driver can easily identify the multiple pedestrians.

A fifth aspect of the present invention is the pedestrian-vehicle communication system according to the fourth aspect, wherein the turn-on instruction generator of the in-vehicle terminal device generates turn-on instruction information which causes the indicator light without any assigned light color to be turned on in a prescribed light color based on color information transmitted from the pedestrian terminal device.

According to the fifth aspect of the present invention, the indicator light of a pedestrian having a collision risks can be turned on in an appropriate light color.

A sixth aspect of the present invention is the pedestrian-vehicle communication system according to the first aspect, wherein the in-vehicle terminal device comprises a display controller configure to display an image representing a position of the pedestrian superimposed on a map image on a display screen of a display device mounted on the vehicle, and wherein the display controller causes the display device to display the image representing the position of the pedestrian in a same color as the light color of the indicator light of the pedestrian.

According to the sixth aspect of the present invention, since the color of an indication of each pedestrian displayed on the display device of the vehicle matches the light color of a corresponding indicator light of the pedestrian, the driver of the vehicle can instantly grasp the correspondence between each of the actual pedestrians and a corresponding pedestrian indication on the display screen of the display device. This enables the driver to quickly confirm each actual pedestrian by reference to the display screen of the display device. In particular, when different light colors are assigned to respective pedestrians, the driver of the vehicle can easily grasp the correspondence between the actual pedestrians and the respective pedestrians displayed on the display screen of the display device.

A seventh aspect of the present invention is a pedestrian-vehicle communication system comprising an in-vehicle terminal device mounted on a vehicle and a pedestrian terminal device carried by a pedestrian, wherein pedestrian position information and vehicle position information are transmitted and received between the in-vehicle terminal device and the pedestrian terminal device via pedestrian-vehicle communication, wherein the pedestrian terminal device comprises: a collision determiner configured to determine a collision risk based on the pedestrian position information and the vehicle position information; a turn-on controller configured, when the collision determiner determines that the collision risk is present, to turn on an indicator light carried by the pedestrian in a prescribed light color, and wherein the in-vehicle terminal device comprises: a pedestrian-vehicle communicator configured to receive color information indicating the prescribed light color from the pedestrian terminal device; and a display controller configured to cause a display device mounted on the vehicle to display an image representing a position of the pedestrian in a same color as the prescribed light color indicated by the color information.

According to the seventh aspect of the present invention, since the color of an indication of each pedestrian displayed on the display device of the vehicle matches the light color of a corresponding indicator light of the pedestrian, the driver of the vehicle can instantly grasp the correspondence between each of the actual pedestrians and a corresponding pedestrian indication on the display screen of the display device. This enables the driver to quickly confirm each actual pedestrian by reference to the display screen of the display device.

An eighth aspect of the present invention is the pedestrian-vehicle communication system according to the seventh aspect, wherein the turn-on controller of the pedestrian terminal device causes the indicator light to be turned on in the light color which is set depending on a user attribute of the pedestrian.

According to the eighth aspect of the present invention, the driver of the vehicle can easily identify what types of pedestrians are present.

A ninth aspect of the present invention is the pedestrian-vehicle communication system according to the eighth aspect, the user attribute is classified according to a possibility of taking a dangerous action.

According to the ninth aspect of the present invention, the driver of the vehicle can easily identify a pedestrian who is likely to take a dangerous action.

A tenth aspect of the present invention is the pedestrian-vehicle communication system according to the seventh aspect, wherein the collision determiner of the pedestrian terminal device determines a plurality of assistance levels according to the collision risk, and the turn-on controller of the pedestrian terminal device sets the light color depending on the assistance levels.

According to the tenth aspect of the present invention, since the light color varies according to the assistance level, the driver of the vehicle can instantly identify how high a collision risk each pedestrian has.

An eleventh aspect of the present invention is the pedestrian-vehicle communication system according to the tenth aspect, wherein, when a plurality of vehicles have collision risks with the pedestrian, the turn-on controller of the pedestrian terminal device sets the light color based on the assistance level for the vehicle having a highest collision risk with the pedestrian.

According to the eleventh aspect of the present invention, since the light color is set based on the assistance level chosen with priority given to that associated with the vehicle having the highest collision risk, the driver of the vehicle can quickly recognize a pedestrian having a high collision risk with the own vehicle.

A twelfth aspect of the present invention is the pedestrian-vehicle communication system according to the first aspect, the collision determiner of the pedestrian terminal device determines a plurality of assistance levels according to on the collision risk, and the turn-on controller of the pedestrian terminal device changes a turn-on pattern of the indicator light depending on the assistance levels.

According to the twelfth aspect of the present invention, since the turn-on pattern (e.g. fast blinking, slow blinking, or always-on) of the indicator light changes according to the assistance level, the driver of the vehicle can quickly identify how high a collision risk each pedestrian has.

A thirteenth aspect of the present invention is an in-vehicle terminal device mounted on a vehicle for performing pedestrian-vehicle communication with a pedestrian terminal device carried by a pedestrian, wherein pedestrian position information and vehicle position information are transmitted and received between the in-vehicle terminal device and the pedestrian terminal device via the pedestrian-vehicle communication, comprising: a collision determiner configured to determine a collision risk based on the pedestrian position information and the vehicle position information; a turn-on instruction generator configured to generate turn-on instruction information which, when the collision determiner determines that the pedestrian has the collision risk, causes an indicator light carried by the pedestrian to be turned on in a prescribed light color; and a pedestrian-vehicle communicator configured to transmit the turn-on instruction information to the pedestrian terminal device via the pedestrian-vehicle communication.

According to the thirteenth aspect of the present invention, since the indicator light carried by the pedestrian having a collision risk is turned on according to the instruction from the in-vehicle terminal device, the driver can quickly and assuredly recognize such pedestrians having collision risks.

A fourteenth aspect of the present invention is an in-vehicle terminal device mounted on a vehicle for performing pedestrian-vehicle communication with a pedestrian terminal device carried by a pedestrian, wherein pedestrian position information and vehicle position information are transmitted and received between the in-vehicle terminal device and the pedestrian terminal device via the pedestrian-vehicle communication, comprising: a pedestrian-vehicle communicator configured to receive color information from the pedestrian terminal device, the color information indicating a light color of an indicator light carried by the pedestrian; and a display controller mounted on the vehicle configured to cause a display device mounted on the vehicle to display an image representing a position of the pedestrian in a same color as the light color indicated by the color information.

According to the fourteenth aspect of the present invention, since the color of an image indicating each pedestrian displayed on the display device of the vehicle matches the light color of a corresponding indicator light of the pedestrian, the driver of the vehicle can instantly grasp the correspondence between each of the actual pedestrians and a corresponding pedestrian indication on the display screen of the display device.

A fifteenth aspect of the present invention is a pedestrian terminal device carried by a pedestrian for performing pedestrian-vehicle communication with an in-vehicle terminal device mounted on a vehicle, wherein pedestrian position information and vehicle position information are transmitted and received between the in-vehicle terminal device and the pedestrian terminal device via the pedestrian-vehicle communication, comprising: a short range communicator configured to perform communication with an indicator light carried by the pedestrian; a pedestrian-vehicle communicator configured to receive turn-on instruction information from the in-vehicle terminal device, the turn-on instruction information causing the indicator light carried by the pedestrian to be turned on in a prescribed light color; and a turn-on controller to turn on the indicator light by the short range communicator based on the turn-on instruction information.

According to the fifteenth aspect of the present invention, since the indicator light carried by the pedestrian having a collision risk is turned on according to the instruction from the in-vehicle terminal device, the driver can quickly and assuredly recognize such pedestrians having collision risks.

A sixteenth aspect of the present invention is a pedestrian terminal device carried by a pedestrian for performing pedestrian-vehicle communication with an in-vehicle terminal device mounted on a vehicle, wherein pedestrian position information and vehicle position information are transmitted and received between the in-vehicle terminal device and the pedestrian terminal device via the pedestrian-vehicle communication, comprising: a short range communicator configured to perform communication with an indicator light carried by the pedestrian; an information storage configured to store color information which causes the indicator light to be turned on; a collision determiner configured to determine a collision risk based on the pedestrian position information and the vehicle position information; a turn-on controller configured to, when the collision determiner determines that the collision risk is present, causes the short range communicator to turn on the indicator light based on the color information; and a pedestrian-vehicle communicator configured to transmit the color information to the in-vehicle terminal device via the pedestrian-vehicle communication.

According to the sixteenth aspect of the present invention, since the pedestrian having a collision risk with the vehicle is turned on in a prescribed color and the light color is notified to the in-vehicle terminal device, an indication of the pedestrian can be displayed on the display device of the vehicle in the same color as the light color of the actual pedestrian. As a result, the driver of the vehicle can instantly grasp the correspondence between each of the actual pedestrians and a corresponding pedestrian indication on the display screen of the display device.

A seventeenth aspect of the present invention, a safe-driving assistance method for assisting a driver in driving a vehicle by performing pedestrian-vehicle communication through which pedestrian position information and vehicle position information are transmitted and received between an in-vehicle terminal device mounted on the vehicle and a pedestrian terminal device carried by a pedestrian, wherein the in-vehicle terminal device: determines a collision risk based on the pedestrian position information and the vehicle position information; generates turn-on instruction information which, when the collision determiner determines that the pedestrian has the collision risk, causes an indicator light carried by the pedestrian to be turned on in a prescribed light color; and transmits the turn-on instruction information to the pedestrian terminal device via the pedestrian-vehicle communication; and wherein the pedestrian terminal device: receives the turn-on instruction information transmitted from the in-vehicle terminal device; and turns on the indicator light based on the turn-on instruction information.

According to the seventeenth aspect of the present invention, since the indicator light carried by the pedestrian having a collision risk is turned on in the same manner as the first aspect, the driver can quickly and assuredly recognize such pedestrians having collision risks.

An eighteenth aspect of the present invention is a safe-driving assistance method for assisting a driver in driving a vehicle by performing pedestrian-vehicle communication through which pedestrian position information and vehicle position information are transmitted and received between an in-vehicle terminal device mounted on the vehicle and a pedestrian terminal device carried by a pedestrian, wherein the pedestrian terminal device: determines a collision risk based on the pedestrian position information and the vehicle position information; when the collision determiner determines that the collision risk is present, turns on an indicator light carried by the pedestrian in a prescribed light color; and transmits color information indicating the prescribed light color to the in-vehicle terminal device via the pedestrian-vehicle communication, and wherein the in-vehicle terminal device: receives the color information transmitted from the pedestrian terminal device; and causes a display device mounted on the vehicle to display an image representing a position of the pedestrian in a same color as the light color of the indicator light of the pedestrian.

According to the eighteenth aspect of the present invention, since the color of an indication of each pedestrian displayed on the display device of the vehicle matches the light color of a corresponding indicator light of the pedestrian in the same manner as the seventh aspect, the driver of the vehicle can instantly grasp the correspondence between each of the actual pedestrians and a corresponding pedestrian indication on the display screen of the display device. This enables the driver to quickly confirm each actual pedestrian by reference to the display screen of the display device.

First Embodiment

FIG. 1is a diagram showing a general configuration of a pedestrian-vehicle communication system according to a first embodiment of the present invention.

The pedestrian-vehicle communication system includes a pedestrian terminal device1(pedestrian-carried pedestrian terminal device), a mobile information terminal device2equipped with an indicator light3, and an in-vehicle terminal device4and a navigation device5(display device) mounted on a vehicle.

The pedestrian terminal device1has a positioning function for acquiring position information of the device itself, and a communication function for performing a pedestrian-vehicle communication with the in-vehicle terminal device4. Based on the positions, traveling directions, traveling speeds and other pieces of information of the pedestrian and the vehicle acquired by using these functions, the pedestrian terminal device1makes collision determination; that is, determines whether or not there is a vehicle which has a collide risk with the pedestrian who owns the pedestrian terminal device.

The mobile information terminal device2may be a smartphone, a mobile phone, a tablet terminal, a wearable terminal, or other types of terminals. The pedestrian terminal device1and the mobile information terminal device2are connected to each other, and when the pedestrian terminal device1determines that the pedestrian terminal device has a high collision risk with a vehicle, the pedestrian terminal device1causes the mobile information terminal device2to perform an assist operation (e.g., voice announcement or vibration) for the pedestrian in order to avoid the occurrence of an accident. In some cases, the pedestrian terminal device1itself may perform the assist operation.

The indicator light3is carried by the pedestrian, and causes drivers of vehicles to recognize the presence of the pedestrian, and includes an LED as a light source, a control circuit, a battery and other elements. In order to have the indicator light3always visible from vehicle drivers, the indicator light3is configured to have an attachment such as a key ring or a strap that can be attached to the pedestrian's belongings, such as a bag, or be a wearable accessory such as a bracelet which can be worn by the pedestrian. The indicator light may be designed as a wearable terminal. The indicator light3also has a communication function for communicating with the pedestrian terminal device1, and its turn-on and turn-off operations are controlled by the pedestrian terminal device1. In some embodiments, the indicator light3may be integrally provided in the pedestrian terminal device1or the mobile information terminal device2.

The in-vehicle terminal device4has a positioning function of acquiring information on the position of the device itself, and a communication function of performing pedestrian-vehicle communication with the pedestrian terminal device1. Based on the positions, traveling directions, traveling speeds, and other pieces of information of the pedestrian and the vehicle acquired by using these functions, the in-vehicle terminal device makes a collision determination; that is, determines whether or not the vehicle on which the device is mounted has a collision risk with a pedestrian.

The navigation device5provides route guidance for the driver. The in-vehicle terminal device4and the navigation device5are connected to each other, and when the in-vehicle terminal device4determines that the in-vehicle terminal device has a high collision risk with pedestrian, the in-vehicle terminal device4causes the navigation device5to perform an assist operation (e.g., voice announcement or display) for the driver in order to avoid the occurrence of an accident. In some cases, the in-vehicle terminal device4itself may perform the assist operation.

The in-vehicle terminal device4may be connected to the mobile information terminal device2possessed by the driver to thereby allow the mobile information terminal device2to perform an assist operation for the driver.

The pedestrian terminal device1may be built into the mobile information terminal device2, and the in-vehicle terminal device4may be built into the navigation device5.

In this pedestrian-vehicle communication system, the pedestrian terminal device1and the in-vehicle terminal device4mutually exchange information such as the positions, the traveling directions, and the traveling speeds of the pedestrian and the vehicle, which are needed to make the collision determination(s), via the pedestrian-vehicle communication using a frequency band (for example, 700 MHz band or 5.8 GHz band), which is adopted in safe driver assistance wireless systems utilizing an ITS (Intelligent Transport System).

In the pedestrian-vehicle communication, messages are transmitted and received between the pedestrian terminal device1and the in-vehicle terminal device4. The messages transmitted from pedestrian terminal device1includes pedestrian position information, information on the traveling direction and traveling speed of the pedestrian acquired by a sensor (not shown) provided on the pedestrian terminal device1or on the mobile information terminal device2, and pedestrian information such as identification information of the pedestrian terminal device1(pedestrian ID, MAC address, etc.).

Next, the schematic configuration of the pedestrian terminal device1will be described.FIG. 2is a block diagram showing a schematic configuration of the pedestrian terminal device1.

The pedestrian terminal device1includes a positioner (position information acquirer)11, a pedestrian-vehicle communicator12, an I/O section13, a short range communicator14, a controller15, and an information storage16.

The positioner11acquires position information of the device itself by a satellite positioning system such as GPS (Global Positioning System), QZSS (Quasi-Zenith Satellite System), or GLONASS (Global Navigation Satellite System). The position information or information on the position of the mobile device may be acquired using the positioning function of the mobile information terminal device2.

The pedestrian-vehicle communicator12transmits and receives messages to/from the in-vehicle terminal device4via the pedestrian-vehicle communication. In this pedestrian-vehicle communication, wireless communication is performed using a frequency band adopted in a safe driver assistance wireless system utilizing an ITS.

The I/O section13exchanges information with the mobile information terminal device2. The mobile information terminal device2performs an assist operation for the pedestrian based on the information provided from the I/O section13.

The short range communicator14communicates with the indicator light3via short range communication such as Bluetooth (registered trademark). In the present embodiment, the short range communicator transmits information on the light color (e.g., red, yellow, or blue) and on lighting patterns (e.g., fast blinking, slow blinking, always-on) of the indicator light3to the indicator light3, and the indicator light3operates based on the information.

The information storage16stores map information, information on the light color of the indicator light3, a program(s) executed by the controller15, and other information. The system may be configured such that the information storage16acquires the map information from the mobile information terminal device2.

The controller15includes a message transmission controller21, a collision determiner22, an assistance controller23, and a turn-on controller24. The controller15is comprised primarily of a processor, and each functional unit of the controller15is implemented by causing the processor to execute a program(s) stored in the information storage16.

The message transmission controller21controls transmission of messages by the pedestrian-vehicle communicator12. Specifically, the message transmission controller determines, based on the pedestrian position information, whether or not a situation occurs in which the pedestrian information (pedestrian ID and position information, or other information) is required to be transmitted. When determining that the pedestrian information is required to be transmitted, the message transmission controller generates a message including the pedestrian information and causes the pedestrian-vehicle communicator12to transmit the message. In determining whether or not to transmit the massage, the message transmission controller determines whether or not the pedestrian information is required to be transmitted to the in-vehicle terminal device4so as to notify the in-vehicle terminal device4of the presence of the pedestrian, more specifically, the message transmission controller determines whether or not a pedestrian has entered a prescribed dangerous area such as an intersection.

The collision determiner22obtains pedestrian speed information and pedestrian orientation information associated with the pedestrian based on how the pedestrian position information acquired by the positioner11changes, and determines whether or not the pedestrian has a collision risk with a vehicle based on the pedestrian position information, the speed information and the orientation information, as well as vehicle position information, vehicle speed information and vehicle orientation information provided from the in-vehicle terminal device4. In some embodiments, the collision risk may be determined in consideration of the map information.

Moreover, the collision determiner22determines one assistance level from the multiple assistance levels depending on the collision risk. In this assistance level determination, the collision determiner calculates a predicted collision time; that is, the time until the pedestrian collides with the vehicle from the present time based on the speeds and the directions of and the distance between the pedestrian and the vehicle, and compares the predicted collision time with two thresholds to determine which one of three assistance levels (Warn, Alert, Provision of information). Specifically, when the predicted collision time is less than a first threshold (e.g., 2 seconds); that is, when the collision risk is high, the collision determiner determines the assistance level to be Warn, when the predicted collision time is greater than or equal to the first threshold and less than a second threshold (e.g., 5 seconds); that is, when the collision risk is moderate, the collision determiner determines the assistance level to be Alert, and when the predicted collision time is greater than the second threshold (e.g., 5 seconds); that is the collision risk is low, the collision determiner determines the assistance level to be Provision of information.

The assistance controller23controls the assist operation for the pedestrian based on the assistance level (Warn, Alert, Provision of information) determined by the collision determiner22. In the assist operation for the pedestrian, the assistance controller, according to the assistance level, causes a speaker provided on the mobile information terminal device2to output a warning sound or a warning voice announcement, or causes a vibrator provided on the mobile information terminal device2to vibrate.

The turn-on controller24controls turning on and off of the indicator light3. In the present embodiment, the turn-on controller turns on the indicator light3based on the turn-on instruction information transmitted from the in-vehicle terminal device4. In this case, the turn-on controller turns on the indicator light3in a light color designated by the turn-on instruction information, and changes the turn-on pattern of the indicator light3according to the assistance level determined by the collision determiner22. When receiving multiple pieces of the turn-on instruction information from the multiple in-vehicle terminal devices4, the turn-on controller determines the light color based on one of those pieces of the turn-on instruction information chosen with priority given to that transmitted from the in-vehicle terminal device4of the vehicle having a highest collision risk.

Next, the schematic configuration of the in-vehicle terminal device4will be described.FIG. 3is a block diagram showing a schematic configuration of the in-vehicle terminal device4.

The in-vehicle terminal device4includes a positioner (position information acquirer)31, a pedestrian-vehicle communicator32, an I/O section33, a controller34, and an information storage35.

The positioner31acquires position information of the device itself by a satellite positioning system in the same manner as the positioner11of the pedestrian terminal device1. The position information of the device itself may be acquired using the positioning function of the navigation device5.

The pedestrian-vehicle communicator32transmits and receives messages to/from the pedestrian terminal device1via the pedestrian-vehicle communication. In this pedestrian-vehicle communication, wireless communication is performed using a frequency band adopted in a safe driver assistance wireless system utilizing an ITS in the same manner as the pedestrian-vehicle communicator12of the pedestrian terminal device1.

The I/O section33exchanges information with the navigation device5. The navigation device5performs the assist operation for the driver based on the information provided from the I/O section33.

The information storage35stores map information, a program(s) executed by the controller34, and other information. The system may be configured such that the information storage35acquires the map information from the navigation device5.

The controller34includes a message transmission controller41, a collision determiner42, an assistance controller43, a turn-on instruction generator44, and a display controller45. The controller34is comprised primarily of a processor, and the functional units of the controller34are implemented by causing the processor to execute a program(s) stored in the information storage35.

The message transmission controller41controls transmission of a message by the pedestrian-vehicle communicator32. In the present embodiment, the message transmission controller generates a message including the pedestrian information and the turn-on instruction information generated by the turn-on instruction generator44, and causes the pedestrian-vehicle communicator32to transmit the message.

The collision determiner42obtains vehicle speed information and vehicle orientation information associated with the vehicle based on how the vehicle position information acquired by the positioner11changes, and determines whether or not the vehicle has a collision risk with a pedestrian based on the vehicle position information, the vehicle speed information and the vehicle orientation information, as well as the pedestrian position information, the pedestrian speed information and the pedestrian orientation information provided from the pedestrian terminal device1. In some embodiments, the collision determiner42determines one of the multiple assistance levels (Warn, Alert, Provision of information) according to the collision risk in the same manner as the collision determiner22of the pedestrian terminal device1.

The assistance controller43controls the assist operation for the pedestrian based on the assistance level (Warn, Alert, Provision of information) determined by the collision determiner42. In the assist operation for the driver, the assistance controller, according to the assistance level, causes a speaker provided on the navigation device5to output a warning sound or a warning voice announcement, or causes the navigation device5to display warning words on its display screen.

The turn-on instruction generator44generates turn-on instruction information, which causes the indicator light3carried by the pedestrian who is determined to have a collision risk by the collision determiner42to be turned on. A message including the turn-on instruction information is transmitted from the pedestrian-vehicle communicator32to the pedestrian terminal device1.

The display controller45displays an image of a pedestrian mark (indication image representing the position of the pedestrian) superimposed on a map image on the display screen of the navigation device5. The display controller causes the display device to display the pedestrian mark in the same color as the light color of the indicator light of the pedestrian.

Next, some situations regarding how the indicator lights3of the pedestrians are turned on will be described.FIG. 4is an explanatory view showing a situation regarding how the indicator lights3of pedestrians are turned on viewed from a vehicle interior.FIG. 5is an explanatory view showing other situations regarding how the indicator lights3of pedestrians are turned on.

In the present embodiment, the in-vehicle terminal device4determines whether or not the vehicle itself has a collision risk with a pedestrian. When the vehicle has a collision risk with a pedestrian, control is made to turn on the indicator light3of the pedestrian with which the vehicle has the collision risk.

An example shown inFIG. 4is a case where a vehicle makes a right turn at an intersection at night. As shown in the figure, although recognizing pedestrians by eyes becomes difficult during night time, turning on the indicator lights3of the pedestrians allows the driver to quickly recognize that the pedestrians are present. In particular, in the present embodiment, the indicator lights3of the pedestrians with which the vehicle has collision risks are turned on, whereas the indicator light3of the pedestrian with which the vehicle has no collision risk is not turned on. Thus, the driver can instantly recognize only the pedestrians having collision risks with the own vehicle.

As shown inFIG. 5(A), the in-vehicle terminal device4makes a collision determination to determine collision risks of pedestrians nearby with the own vehicle, and if a pedestrian having a collision risk with the vehicle is present, the in-vehicle terminal device instructs the pedestrian terminal device1of the pedestrian with the collision risk to turn on the indicator lights3. As a result, the indicator lights3of the pedestrians having collision risks with the own vehicle are turned on, so that the driver of the vehicle can recognize the pedestrians having collision risks with the vehicle.

The in-vehicle terminal device4holds in advance color information on a light color specific to the vehicle itself, and instructs the pedestrian terminal device1to turn on the indicator lights3in the light color specific to the vehicle. For this reason, the indicator lights3of the pedestrians having collision risks with the single vehicle are turned on in the same light color. The color information on a light color specific to each vehicle may be set in advance by the driver via the navigation device5and may be set based on, for example, the color of each vehicle body.

In addition, in the present embodiment, the turn-on pattern of each indicator light3is changed according to the assistance level set based on the collision determination. Specifically, when the assistance level is Warn, an indicator light is controlled to blink fast; that is, the turn-on pattern is set to be fast blinking with a short blink cycle, when the assistance level is Alert, an indicator light is controlled to blink slowly; that is, the turn-on pattern is set to be slow blinking with an longer blink cycle, and when the assistance level is Provision of information, the turn-on pattern of an indicator light is maintained turned on.

In an example shown inFIG. 5(A), a vehicle C1, which makes a right turn, has collision risks with pedestrians P1, P2, and P3, and depending on the degree of danger or risk, the assistance level of the pedestrian P1is set to be Warn, the assistance level of the pedestrian P2is set to be Alert, and the assistance level of the pedestrian P3is set to be Provision of information. In addition, the light color specific to the vehicle C1is red in this embodiment.

In this case, the in-vehicle terminal device4of the vehicle C1transmits a turn-on instruction to blink fast in red to the pedestrian terminal device1in the pedestrian P1, so that the indicator light3in the pedestrian P1blinks fast in red. The in-vehicle terminal device of the vehicle C1also transmits a tune-on instruction to blink slowly in red to the pedestrian terminal device1of the pedestrian P2, so that the indicator light3of the pedestrian P2blinks slowly in red. In addition, the in-vehicle terminal device of the vehicle C1transmits a turn-on instruction to continuously turn on in red to the pedestrian terminal device1of the pedestrian P3, so that the indicator light3of the pedestrian P3is maintained turned on in red. Since the pedestrian P4has no collision risk with the vehicle C1, the indicator light3of the pedestrian P4remains turned off.

When there are multiple vehicles in the vicinity, each pedestrian can have different collision risks with different vehicles. Also, even when multiple vehicles have collision risks with pedestrians, each pedestrian has different assistance levels for the different vehicles. For this reason, in the pedestrian terminal device1, conflicts can occur between turn-on instructions from the multiple in-vehicle terminal devices4. Thus, in the present embodiment, when receiving turn-on instructions from the multiple in-vehicle terminal devices4, the pedestrian terminal device compares the assistance levels from the in-vehicle terminal devices with one another, and sets the light color and the turn-on pattern based on the turn-on instruction information chosen with priority given to that from the in-vehicle terminal device of the vehicle having the highest collision risk represented by the assistance level.

In the example shown inFIG. 5(B), since the pedestrian P2travels in the direction of the road, the vehicle C2going straight down should have a high collision risk with the pedestrian P2and the assistance level for the vehicle C2is set to be Warn. In this case, when the color specific to the vehicle C2is blue, the in-vehicle terminal device4of the vehicle C2transmits turn-on instructions to blink fast in blue to the pedestrian terminal device1of the pedestrian P2. Meanwhile, since the assistance level of the vehicle C1of the pedestrian P2is set to be Alert and the vehicle C2has a higher collision risk, priority is given to the turn-on instructions from the in-vehicle terminal device4of the vehicle C2and the indicator light3of the pedestrian P2blinks fast in blue.

Next, the display screen of the navigation device5will be described.FIG. 6is an explanatory view showing images displayed on the display screen of the navigation device5.

The display screen of the navigation device5displays assistance images for the driver of the vehicle according to the assistance level determined based on the collision determination. In the example ofFIG. 6, the images displayed in the display screen include the words “Caution—Pedestrian Near Crossing in Right Turn Path.”

The images displayed in the display screen of the navigation device5include pedestrian marks52at the positions of pedestrians in a map image51. The pedestrian marks52represent only the pedestrians having collision risks with the vehicle and are displayed in the same color as the light color of the indicator lights3. Moreover, each pedestrian mark52is displayed in a display pattern determined according to the degree of collision risk, as in the case of the indicator light3. That is, when the assistance level is Warn, the mark blinks fast, when the assistance level is Alert, the mark blinks slowly, and when the assistance level is Provision of information, the mark is maintained turned on.

Under the conditions, when a pedestrian having a collision risk with the vehicle is present, the navigation device5performs an assist operation for the driver, e.g. serving voice announcement or image displayed on the display screen. In response to the assist operation, the driver attempts to confirm the position of the pedestrian which is actually present ahead of the vehicle. In this situation, the driver can check the pedestrian mark52displayed on the display screen of the navigation device5so as to grasp an area in which the pedestrian is actually present to thereby find the blinking indicator light3in the area. As a result, the time required for the driver to grasp the position of the pedestrian becomes short, which means that the driver can quickly grasp the actual position of the pedestrian.

In particular, in the present embodiment, the pedestrian mark52is displayed on the display screen of the navigation device5in the same display mode as the light color and the turn-on pattern of the indicator light3of each pedestrian. Thus, the driver can easily recognize pedestrians present nearby and instantly grasp the degree of a collision risk for each pedestrian.

FIG. 6(A)shows an image displayed on the display screen of the navigation device5of the vehicle C1in the case that a single vehicle is present as shown inFIG. 5(A). In this case, the pedestrian mark52is displayed on the display screen of the navigation device5of the vehicle C1in the same display mode as the indicator light3of the pedestrian. That is, the pedestrian mark52of the pedestrian P1blinks fast in red, the pedestrian mark52of the pedestrian P2blinks slowly in the red, and the pedestrian mark52of the pedestrian P3is maintained turned on in red.

FIG. 6(B)shows an image displayed on the display screen of the navigation device5of the vehicle C1in the case that multiple vehicles are present nearby as shown inFIG. 5(B). In this case, the assistance level of the vehicle C2is Warn, and since the vehicle C2has a higher collision risk than the vehicle C1, the pedestrian mark52of the pedestrian P2blinks fast in blue, which color is specific to the vehicle C2. In this situation, since the color specific to the vehicle C1is red, the driver of the vehicle C1can recognize that the pedestrian mark52of the pedestrian P2displayed in blue is not displayed based on the collision risk with the own vehicle.

When conflicts occur between the turn-on instructions from multiple in-vehicle terminal devices4and the turn-on instructions from the vehicle having a highest collision risk is used, the in-vehicle terminal devices4in the remaining three vehicles do not know the light color of the actual indicator lights3. Thus, in the present embodiment, when the indicator light3is turned on in a color different from that designed by the turn-on instructions, the light color which is actually adopted is notified to the in-vehicle terminal devices4. In this way, the color of the pedestrian mark52displayed on the navigation device5matches the light color of the indicator light3.

The pedestrian mark52may be displayed on the display screen of the navigation device5in the color specific to the own vehicle, regardless of the light color which is actually adopted. In this case, since the color of the pedestrian mark52displayed on the navigation device5does not match the actual light color of the indicator light3, the navigation device5is preferably configured to display an image such as characters indicating that the indicator light3is turned on in the color designed by the instructions from the in-vehicle terminal device4of another vehicle.

Furthermore, when the color specific to one vehicle is the same as that specific to another vehicle, the driver cannot determine whether or not the displayed pedestrian mark52is associated with the collision risk with the own vehicle. In this case, the navigation device5is preferably configured to display an image such as characters indicating that the displayed pedestrian mark52has the color determined based on the collision risks associated with another vehicle on the display screen.

Next, operation procedures of the pedestrian terminal device1and the in-vehicle terminal device4will be described.FIG. 7is a flow chart showing operation procedures of the pedestrian terminal device1and the in-vehicle terminal device4.

In the pedestrian terminal device1, first, the positioner11acquires pedestrian position information (ST101). Next, the message transmission controller21determines whether or not to transmit the pedestrian information, more specifically, determines whether or not the pedestrian has entered the risky or dangerous area (ST102). In the case where the pedestrian information is to be transmitted (Yes in ST102), the pedestrian-vehicle communicator12transmits a message including the pedestrian information (pedestrian ID, location information, or other information) via the pedestrian-vehicle communication (ST103).

In the in-vehicle terminal device4, upon receiving the message transmitted from the pedestrian terminal device1(ST201), the pedestrian-vehicle communicator32makes a collision determination to determine, based on the pedestrian position information and other information, whether or not the vehicle has a collision risk with a pedestrian (ST202). Then, the assistance controller43determines, based on the determination result of the collision determiner42, whether or not the navigation device needs to perform an assist operation for the driver (ST203).

In the case where the assist operation for the driver is necessary (Yes in ST203), the turn-on instruction generator44generates the turn-on instruction information to cause the indicator light3to be turned on in a light color which can be designated by the color information stored in the information storage35and is specific to the own vehicle (ST204). Then, the pedestrian-vehicle communicator32transmits a message including the turn-on instruction information and the vehicle information (such as vehicle ID and position information) via the pedestrian-vehicle communication (ST205).

The assistance controller43performs the assist operation for the driver (ST206). In the assist operation for this driver, the assistance controller controls the assist operation based on the assistance level (Warn, Alert, Provision of information) so as to cause the navigation device to output a warning sound or a warning voice announcement, or cause the navigation device to display warning words on its display screen.

The display controller45displays the pedestrian mark52on the display screen of the navigation device5. The pedestrian mark52is displayed in the same color as that designed by the turn-on instruction information; that is, the color specific to the own vehicle. In addition, the pedestrian mark52is displayed in a display pattern (fast blinking, slow blinking, or always-on) determined based on the assistance level (Warn, Alert, Provision of information).

In the pedestrian terminal device1, when the pedestrian-vehicle communicator12receives the message transmitted from the in-vehicle terminal device4(ST104), the collision determiner22makes a collision determination to determine whether or not the pedestrian has a collision risk with a vehicle based on the vehicle position information or other information included in the message (ST105). Then, based on the determination result of the collision determiner42, the assistance controller23determines whether or not an assist operation is necessary for the pedestrian (ST106).

In the case where the assist operation is necessary for the pedestrian (Yes in ST106), the assistance controller23performs the assist operation for the pedestrian (ST107). In the assist operation for the pedestrian, the assistance controller, according to the assistance level (Warn, Alert, and Provision of information), causes the mobile information terminal device to output a warning sound or a warning voice announcement, or causes a vibrator provided on the mobile information terminal device to vibrate.

Furthermore, the turn-on controller24turns on the indicator light3based on the turn-on instruction information included in the message (ST108). In this situation, the turn-on controller turns on the indicator light3in a turn-on pattern (Fast blinking, Slow blinking, Always-on) according to the assistance level (Warn, Alert, or Provision of information). When receiving multiple pieces of the turn-on instruction information from the multiple in-vehicle terminal devices4, the turn-on controller gives priority to the turn-on instruction information transmitted from the in-vehicle terminal device4of the vehicle having the highest collision risk to choose the turn-on instruction information on which the light color is determined. When the assist operation is not necessary (No in ST106), the turn-on controller turns off the indicator light3(ST109).

Second Embodiment

Next, a second embodiment of the present invention will be described.FIG. 8is an explanatory view showing a situation regarding how indicator lights3of pedestrians are turned on in a system according to a second embodiment of the present invention. Except for what will be discussed here, the configuration of the present embodiment is the same as that of the first embodiment.

In the present embodiment, the in-vehicle terminal device4instructs the pedestrian terminal device1to turn on the indicator light3in the same manner as in the first embodiment. However, in the second embodiment, different light colors are assigned to pedestrians so that the indicator lights3of the pedestrians are turned on in respective different colors.

In the present embodiment, the turn-on pattern of the indicator light3is changed according to the assistance level (collision risk level) in the same manner as in the first embodiment. For example, when the assistance level is Warn, the indicator light is controlled to blink fast, when the assistance level is Alert, the indicator light is controlled to blink slowly, and when the assistance level is Provision of information, the indicator light is controlled to be maintained turned on.

In the example shown inFIG. 8, the vehicle C1, which is to make a right turn, has collision risks with the pedestrian P1, P2and P3, and the assistance levels for the pedestrians P1, P2, and P3are Warn, Alert, and Provision of information, respectively. In addition, the pedestrian P1is assigned a red color, the pedestrian P2is assigned a blue color, and the pedestrian P3is assigned a yellow color.

In this case, the in-vehicle terminal device4of the vehicle C1transmits turn-on instruction information to instruct the indicator light to blink fast in red to the pedestrian terminal device1of the pedestrian P1so that the indicator light3of the pedestrian P1blinks fast in red. The in-vehicle terminal device transmits turn-on instruction information to instruct the indicator light to blink slowly in blue to the pedestrian terminal device1of the pedestrian P2so that the indicator light3of the pedestrian P2blinks slowly in blue. The in-vehicle terminal device transmits turn-on instruction information to instruct the indicator light to be maintained turned on so that the indicator light3of the pedestrian P3is maintained turned on in yellow.

In cases where there are multiple vehicles in the vicinity, when the in-vehicle terminal device4of each vehicle issues turn-on instructions, in the pedestrian terminal device1, conflicts can occur between turn-on instructions from multiple in-vehicle terminal devices4. Therefore, in the present embodiment, for a pedestrian(s) to which a color has already been assigned by the turn-on instructions from the in-vehicle terminal device4, priority is given to the already assigned color, and for the nearby pedestrians to which any colors have not yet been assigned, the in-vehicle terminal device4assigns a color to each of those pedestrians.

When a pedestrian with an assigned color becomes to have no collision risk with the vehicle and its indicator light3is turned off, the state of the pedestrian is reset such that the pedestrian has no assigned color.

When there are multiple vehicles in the vicinity, each pedestrian has different collision risks with the respective vehicles. Also, even when multiple vehicles have collisions risks with pedestrians, each pedestrian has different assistance levels for the respective vehicle. Thus, in the present embodiment, when receiving turn-on instructions from multiple in-vehicle terminal devices4, the pedestrian terminal device compares the assistance levels from their in-vehicle terminal devices with one another, and sets the turn-on pattern (fast blinking, slow blinking, or always-on) based on the turn-on instruction information chosen with priority given to that from the in-vehicle terminal device of the vehicle having the highest collision risk represented by the assistance level.

Next, the display screen of the navigation device5will be described.FIG. 9is an explanatory view showing an image displayed on the display screen of the navigation device5.

The display screen of the navigation device5displays assistance images for the driver of the vehicle according to the assistance level determined based on the collision determination in the same manner as the first embodiment. In the example ofFIG. 9, the images displayed in the display screen include the words “Caution—Pedestrian Near Crossing in Right Turn Path.”

The images displayed in the display screen of the navigation device5include pedestrian marks52at the positions of pedestrians with which the vehicle has collision risks in a map image51. By having a pedestrian terminal device1notify the in-vehicle terminal device4of the color of the actual turned-on light of the pedestrian terminal device1, each pedestrian mark52can be displayed in the same color as that of the light from a corresponding indicator light3. In the example shown inFIG. 9, the pedestrian mark52of the pedestrian P1blinks fast in red, the pedestrian mark52of the pedestrian P2blinks slowly in blue, and the pedestrian mark52of the pedestrian P3is maintained turned on in yellow.

In the present embodiment, from the pedestrian terminal device1of the pedestrian to which a color has already been assigned, the assigned color is notified to the in-vehicle terminal device4. In addition, since the in-vehicle terminal device4assigns colors only to pedestrians to which any colors have not yet been assigned, it is ensured that each of the colors of the pedestrian marks52displayed on the navigation device5matches the light color of a corresponding indicator light3.

Next, operation procedures of the pedestrian terminal device1and the in-vehicle terminal device4will be described.FIG. 10is a flow chart showing operation procedures of the pedestrian terminal device1and the in-vehicle terminal device4.

In the present embodiment, the operation procedures of the pedestrian terminal device1and the in-vehicle terminal device4are generally similar to those shownFIG. 7, but different from those inFIG. 7in that, in the present embodiment, when the pedestrian terminal device1transmits a message including pedestrian information via the pedestrian-vehicle communication (ST103), if a color has already been assigned to the pedestrian terminal device, color information on the assigned light color is added to the message.

The operation procedures of the present embodiment are also different from those of the first embodiment in that, the in-vehicle terminal device4can generate turn-on instruction information (ST204) such that the turn-on instruction information causes the indicator light3to be turned on in an assigned light color. If the message from the pedestrian terminal device1does not contain color information on an assigned light color, the in-vehicle terminal device4assigns a light color to the pedestrian, whereas if the message from the pedestrian terminal device1contains color information on an assigned light color, the in-vehicle terminal device4assigns a color different from the assigned light color to another pedestrian.

In some cases, the system may be configured such that the in-vehicle terminal device4assigns a light color to each pedestrian, regardless of whether or not a light color is already assigned to the pedestrian, and instructs the pedestrian to cause the indicator light to be turned on in the assigned color, and upon receiving the turn-in instructions from multiple in-vehicle terminal devices4, the pedestrian terminal device sets the light color based on the turn-on instruction received at the earliest timing.

In the first embodiment, when a conflict occurs regarding the turn-on instructions, the pedestrian terminal device1chooses the light color based on the assistance level, and in the second embodiment, the in-vehicle terminal device4assigns a color to a pedestrian to which any color has not been assigned. However, conversely, in the configuration in which the indicator light3is turned on in a color specific to the vehicle as in the first embodiment, the in-vehicle terminal device4may assign a color to a pedestrian to which any color has not been assigned, or in the configuration in which indicator lights are turned on in respective different colors as in the second embodiment, the pedestrian terminal device1may choose the light color based on the assistance level.

Third Embodiment

Next, a third embodiment of the present invention will be described.FIG. 11is an explanatory view showing a situation regarding how indicator lights3of pedestrians are turned on in a system according to a third embodiment of the present invention. Except for what will be discussed here, the configuration of the present embodiment is the same as that of the first embodiment.

While, in the first and second embodiments, the indicator light3of a pedestrian is turned on in a light color designated by the in-vehicle terminal device4, in the present embodiment, the pedestrian terminal device1determines the light color of the indicator light3by itself. Particularly, in the present embodiment, the pedestrian terminal device1holds color information on the color specific to each pedestrian, and when having a collision risk with a vehicle, the pedestrian terminal device1turns on the indicator light3in a color specific to the pedestrian.

Furthermore, in the present embodiment, the light color of the indicator light specific to each pedestrian is set in advance; that is, the color specific to a pedestrian is set in advance for each user attribute. In particular, in the present embodiment, user attributes are classified according to the likelihood of taking a dangerous action. For example, a pedestrian who is likely to take a dangerous action, such as an elderly person or a child, is set to red, and a pedestrian with a low risk of taking dangerous actions is set to blue. In addition, a dedicated image may be displayed for a person who needs special considerations, such as a physically challenged person.

The user attribute may be set based on the past action history. Specifically, when a system is configured to detect pedestrians' dangerous actions such as entering a roadway and count the number of times a pedestrian has been taken such actions, the user attribute may be set based on the number of times the pedestrian has taken such dangerous actions.

In the present embodiment, the turn-on pattern of the indicator light3is changed according to the assistance level (collision risk level) in the same manner as the above-described embodiments. For example, when the assistance level is Warn, the indicator light is controlled to blink fast, when the assistance level is Alert, the indicator light is controlled to blink slowly, and when the assistance level is Provision of information, the indicator light is controlled to be maintained turned on.

In the example shown inFIG. 11, the vehicle C1, which is to make a right turn, has collision risks with the pedestrian P1, P2and P3, and the assistance levels for the pedestrians P1, P2, and P3are Warn, Alert, and Provision of information, respectively. The pedestrian P2is an elderly person, who is likely to take dangerous actions, and thus, the pedestrian P1is assigned a red color. As the pedestrians P1and P3are not elderly people or children and are less likely to take dangerous actions, the pedestrians P1and P3are assigned a blue color.

In this case, the indicator light3of the pedestrian P1blinks fast in blue, the indicator light3of the pedestrian P2blinks slowly in red, and the indicator light3of the pedestrian P3is maintained turned on in blue.

When there are multiple vehicles in the vicinity, each pedestrian can have different collision risks with different vehicles. Also, even when multiple vehicles have collision risks with pedestrians, each pedestrian has respective different risks with the different vehicle. Thus, in the present embodiment, when multiple vehicles have collision risks with pedestrians, the pedestrian terminal device compares the assistance levels from in-vehicle terminal devices with one another, and sets the turn-on pattern (fast blinking, slow blinking, always-on) based on the turn-on instruction information chosen with priority given to that from the in-vehicle terminal device of the vehicle having the highest collision risk represented by the assistance level.

In the present embodiment, since the pedestrian light is turned on in a color specific to the pedestrian, no conflict occurs regarding the light color as in the above-described embodiments.

Next, the display screen of the navigation device5will be described.FIG. 12is an explanatory view showing an image displayed on the display screen of the navigation device5.

The display screen of the navigation device5displays assistance images for the driver of the vehicle according to the assistance level determined based on the collision determination in the same manner as the above-described embodiments. In the example ofFIG. 12, the image displayed in the display screen includes the words “Caution—Pedestrian Near Crossing in Right Turn Path.”

The image displayed in the display screen of the navigation device5includes pedestrian marks52at the positions of pedestrians with which the vehicle has collision risks in a map image51in the same manner as the above-described embodiments. By having a pedestrian terminal device1notify the in-vehicle terminal device4of the color specific to the pedestrian, each pedestrian mark52can be displayed in the same color as that of the light from a corresponding indicator light3. In the example shown inFIG. 12, the pedestrian mark52of the pedestrian P1blinks fast in blue, the pedestrian mark52of the pedestrian P2blinks slowly in red, and the pedestrian mark52of the pedestrian P3is maintained turned on in blue; that is, the marks are displayed in the same colors as the indicator lights3of the pedestrian P1, P2, and P3.

A traveling direction of each pedestrian may be indicated by an arrow displayed on the screen display of the navigation device5. Such an arrow may be highlighted, e.g. by thickening the lines, to distinguishably indicate a pedestrian who is traveling fast such as a child riding a bicycle, or a pedestrian who is likely to take dangerous actions such as an elderly person or a child. Alternatively, the color or the line type (solid line, dotted line, etc.) of the arrow may be changed to display the arrow in a distinguishably different manner. Furthermore, based on the past action history regarding dangerous actions, a pedestrian mark for a pedestrian who has frequently taken dangerous actions may be displayed with a special mark (e.g. “x” or “!”) or word (e.g. “caution”) to indicate the caution us required.

Next, operation procedures of the pedestrian terminal device1and the in-vehicle terminal device4will be described.FIG. 13is a flow chart showing operation procedures of the pedestrian terminal device1and the in-vehicle terminal device4.

In the present embodiment, the operation procedures of the pedestrian terminal device1and the in-vehicle terminal device4are generally similar to those shownFIG. 7, but different from those inFIG. 7in that, in the present embodiment, when the pedestrian terminal device1transmits a message including pedestrian information via the pedestrian-vehicle communication (ST103), color information on the color specific to a pedestrian, the color being set according to the user attribute, is added to the message.

The operation procedures of the present embodiment are also different from those of the above-described embodiments in that, when the in-vehicle terminal device4transmits the massage via the pedestrian-vehicle communication (ST205), the message to be transmitted includes vehicle information (such as vehicle ID and position information), but does not include turn-on instruction information as in the above-described embodiments.

Furthermore, in the present embodiment, when the navigation device5in the in-vehicle terminal device4displays the pedestrian mark52on the display screen (ST207), the pedestrian mark52is displayed with the same color as the light color of the indicator light3for each pedestrian based on color information included in the message transmitted from the pedestrian terminal device1.

Moreover, in the present embodiment, when the pedestrian terminal device1turns on the indicator light3(ST108), the indicator light3is turned on in a color specific to the pedestrian, the color being set according to the user attribute.

Fourth Embodiment

Next, a fourth embodiment of the present invention will be described.FIG. 14is an explanatory view showing a situation regarding how indicator lights3of pedestrians are turned on in a system according to a fourth embodiment of the present invention. Except for what will be discussed here, the configuration of the present embodiment is the same as that of the first embodiment.

While, in the first and second embodiments, the indicator light3of a pedestrian is turned on in a light color designated by the in-vehicle terminal device4, in the present embodiment, the pedestrian terminal device1determines the light color of the indicator light3by itself in the same manner as the third embodiment. Particularly, in the present embodiment, the pedestrian terminal device1changes the light color according to the assistance level determined based on the result of the collision determination. For example, when the assistance level is Warn, the color is set to red, and when the assistance level is the color is set to yellow, and when the assistance level is the color is set to blue.

Moreover, in the present embodiment, as in the above-described embodiments, a display pattern of the indicator light3(fast blinking, slow blinking, or always-on) is changed according to the assistance level. For example, when the assistance level is Warn, the display pattern is set to be fast blinking, when the assistance level is Alert, the display pattern is set to be slow blinking, and when the assistance level is Provision of information, the display pattern is set to be always-on.

In the example shown inFIG. 14(A), a vehicle C1, which makes a right turn, has collision risks with pedestrians P1, P2, and P3, and the assistance level of the pedestrian P1is set to be Warn, the assistance level of the pedestrian P2is set to be Alert, and the assistance level of the pedestrian P3is set to be Provision of information. Thus, the indicator light3of the pedestrian P1blinks fast in red, the indicator light3of the pedestrian P2blinks slowly in yellow, and the indicator light3of the pedestrian P3is maintained turned on in blue.

When there are multiple vehicles in the vicinity, each pedestrian can have different collision risks with different vehicles. Also, even when multiple vehicles have collision risks with pedestrians, each pedestrian has different assistance levels for the different vehicle. For this reason, conflicts can occur between the turn-on conditions (light color and turn-on pattern) of the indicator lights3of the pedestrians. Thus, in the present embodiment, when there are multiple vehicles in the vicinity, the pedestrian terminal device compares the assistance levels from in-vehicle terminal devices with one another, and sets the light color and the turn-on pattern based on the turn-on instruction information chosen with priority given to that from the in-vehicle terminal device of the vehicle having the highest collision risk represented by the assistance level.

In the example shown inFIG. 14(B), since the pedestrian P2travels in the direction of the road, the vehicle C2going straight down should have a high collision risk with the pedestrian P2and the assistance level for the vehicle C2is set to be Warn. Meanwhile, since the assistance level of the vehicle C1of the pedestrian P2set to be Alert and the vehicle C2has a higher collision risk, priority is given to the turn-on instructions from the in-vehicle terminal device4of the vehicle C2and the indicator light3of the pedestrian P2blinks fast in red.

Next, the display screen of the navigation device5will be described.FIG. 15is an explanatory view showing images displayed on the display screen of the navigation device5.

The display screen of the navigation device5displays assistance images for the driver of the vehicle according to the assistance level determined based on the collision determination in the same manner as the above-described embodiments. In the example ofFIG. 15, the images displayed in the display screen include the words “Caution—Pedestrian Near Crossing in Right Turn Path.”

The images displayed in the display screen of the navigation device5include pedestrian marks52at the positions of pedestrians having collision risks with the vehicle in a map image51in the same manner as the above-described embodiments. Each pedestrian mark52is displayed in a display mode (light color and turn-on pattern) determined according to the assistance level.

FIG. 15(A)shows an image displayed on the display screen of the navigation device5of the vehicle C1in the case that a single vehicle is present as shown inFIG. 14(A). In this case, the pedestrian mark52is displayed on the display screen of the navigation device5of the vehicle C1in the same display mode as the indicator light3of the pedestrian. That is, the pedestrian mark52of the pedestrian P1blinks fast in red, the pedestrian mark52of the pedestrian P2blinks slowly in yellow, and the pedestrian mark52of the pedestrian P3is maintained turned on in blue.

FIG. 15(B)shows an image displayed on the display screen of the navigation device5of the vehicle C1in the case that multiple vehicles are present nearby as shown inFIG. 14(B). In this case, the assistance level of the vehicle C2is Warn, and since the vehicle C2has a higher collision risk than the vehicle C1, the pedestrian mark52of the pedestrian P2blinks fast in red. Under this condition, the driver of the vehicle C1cannot determine whether the color of the mark is associated with the own vehicle or not. Thus, the navigation device5is preferably configured to display an image such as characters indicating that the pedestrian mark52is associated with another vehicle.

The navigation device5may be configured to display the pedestrian mark52in the display mode determined based on the assistance level associated with the own vehicle. Under this condition, the pedestrian mark52in the display screen is turned on in a different manner from the indicator light3. Thus, the navigation device5is preferably configured to display an image such as characters indicating that the pedestrian mark52is turned on in a different manner from the indicator light3.

Next, operation procedures of the pedestrian terminal device1and the in-vehicle terminal device4will be described.FIG. 16is a flow chart showing operation procedures of the pedestrian terminal device1and the in-vehicle terminal device4.

In the present embodiment, the operation procedures of the pedestrian terminal device1and the in-vehicle terminal device4are generally similar to those shownFIG. 13, but different from those inFIG. 13in that, in the present embodiment, when the pedestrian mark52is displayed on the navigation device5of the in-vehicle terminal device4(ST207), the pedestrian mark52is displayed in a color determined according to the assistance level. (Warn, Alert, Provision of information).

Furthermore, in the present embodiment, when the indicator light3is turned on (ST108), the indicator light3is turned on in a color determined according to the assistance level (Warn, Alert, Provision of information).

Next, time sharing control when conflicts occur between turn-on conditions will be described.FIG. 17is an explanatory view showing a time sharing control when conflicts occur between turn-on conditions.

In making a collision determination to determine collision risks of multiple vehicles present nearby with a pedestrian, due to different collision risk with different vehicles, conflicts can occur between the assistance levels (Warn, Alert, and Provision of information), which determine turn-on conditions. When conflicts occur between the turn-on conditions, time sharing control is performed on the turn-on conditions of the indicator light3and the image displayed on the display screen of the navigation device, which enables the driver of each vehicle to easily grasp the correspondence between each of the actual pedestrians and a corresponding pedestrian indication on the display screen of the navigation device5.

In the example shown inFIG. 16, the pedestrian P2sets the assistance level of the vehicle C1to be Alert, and the vehicle C2to be Warn. In this case, the indicator light3of the pedestrian P2is controlled to be turned on alternately in red and yellow. In the navigation device5of the vehicle C1having the assistance level of Alert for the pedestrian P2, the pedestrian mark52is displayed in yellow at the time when the indicator light3is turned on in yellow. In the navigation device5of the vehicle C2having the assistance level of Warn for the pedestrian P2, the pedestrian mark52is displayed in red at the time when the indicator light3is turned on in red.

In this way, when time sharing control is performed on the turn-on of the indicator light3and the display of the pedestrian mark52, the driver of each vehicle can recognize that the indicator light3associated with the own vehicle is one which is turned on in synchronized with the display of the pedestrian mark52on the navigation device5, and also grasp the levels of the collision risks between the own vehicular and respective pedestrians.

Although the above description has been made with reference to the fourth embodiment, time sharing control for cases where conflicts occur between the turn-on conditions can be applied to other embodiments.

In other embodiments, when conflicts occur between the turn-on conditions, control may be performed on the direction and the color of the light emitted from the indicator light3such that the driver of each vehicle can see the indicator light3turned on in the color for the assistance level associated with the vehicle. In this case, the indicator light3may be configured such that the indicator light can emit lights separately in respective colors and to different directions, and the indicator light3may be controlled to emit lights to respective vehicles in the colors corresponding to the assistance levels associated with the respective vehicles.

While specific embodiments of the present invention are described herein for illustrative purposes, the present invention is not limited thereto. It will be understood that various changes, substitutions, additions, and omissions may be made for elements of the embodiments without departing from the scope of the invention. In addition, elements and features of the different embodiments may be combined with each other as appropriate to yield an embodiment which is within the scope of the present invention.

For example, although in the above-described embodiments, pedestrians; that is, persons walking on the road, carry pedestrian terminal devices, pedestrians in a broad sense may include persons carrying a pedestrian terminal device and riding a bicycle, an electric vehicle for seniors (senior car), an electric wheelchair, a farming machine, or like.

In addition, when certain types of vehicles are approaching, the traveling direction may be indicated by arrows, and examples of such vehicles include vehicles driven by elderly people (four-wheeled vehicles), vehicles of driving training schools (four-wheeled vehicles), vehicles with a beginner driver's mark (four-wheeled vehicles), vehicles driven by drivers without confidence in driving (four-wheeled vehicles), and motorcycles. Since there are many accidents in which vehicles turning left (turning right, in some countries) hit motorcycles, the traveling direction of a motorcycle may be indicated by an arrow only when the vehicle (four-wheeled vehicle) makes a left turn. In some cases, when a dangerous vehicle (four-wheeled vehicle) such as a vehicle weaving or speeding is approaching, the color of the arrow may be changed or an X mark may be attached to the image.

When an emergency vehicle such as an ambulance is approaching, a special indication may be displayed, for example, by changing the color of arrows to indicate emergency vehicles.

In the present embodiment, the in-vehicle terminal device is described as one mounted on a vehicle (four-wheeled vehicle), but the vehicle on which the in-vehicle terminal device is mounted may be a motorcycle or other types of vehicles.

In the above-described embodiments, pedestrians carry the indicator lights and the driver of a vehicle can see lights from the turned-on indicator lights to recognize the pedestrians having certain collision risks with the own vehicle. However, the system may be conversely configured; that is, a vehicle may be equipped with an indicator light so that each pedestrian can recognize the vehicle having a certain collision risk therewith. Alternatively, a mobile information terminal device carried by a pedestrian may be provided with a display screen, on which marks are displayed to indicate the presence of any vehicle having a collision risk with the pedestrian, where the vehicle may be a car, a bicycle, an electric vehicle for seniors (senior car), an electric wheelchair, a farm machine or the like.

Although, in the first and second embodiments, the in-vehicle terminal device instructs the pedestrian terminal device to turn on the pedestrian indicator light in a prescribed light color, turn-on instructions to the pedestrian terminal device may be provided by a roadside device (for example, a controller for a traffic light) disposed on a roadside.

In the second embodiment, the indicator lights of respective pedestrians can be turned on in different light colors and different turn-on patterns. Since, in such a configuration, each pedestrian can be identified by the light color and the turn-on pattern of the indicator light, the position data of pedestrians used in processing such as a collision determination may be corrected by using a camera; that is, the indicator lights are shot by the camera to provide a photograph image showing the actual positional relationship between the vehicle and the pedestrians, which is used to correct position data of the pedestrians.

INDUSTRIAL APPLICABILITY

A pedestrian-vehicle communication system and a safe-driving assistance method according to the present invention achieve the effect of enabling a driver in driving a vehicle to quickly and assuredly recognize a pedestrian having a collision risk with the vehicle even when the driver is unable to easily recognize the pedestrian by eyes, such as during night time, and are useful as a pedestrian-vehicle communication system comprising an in-vehicle terminal device mounted on a vehicle and a pedestrian terminal device carried by a pedestrian, wherein pedestrian position information and vehicle position information are transmitted and received between the in-vehicle terminal device and the pedestrian terminal device via pedestrian-vehicle communication, or a safe-driving assistance method for assisting a driver in driving a vehicle by performing pedestrian-vehicle communication.

GLOSSARY