A reckless-vehicle determination section of a vehicle determines whether a reckless driving operation takes place in each of different vehicles based on determination information from each of the different vehicles. A target different vehicle in which a reckless driving operation is determined to take place is displayed on a display in a display mode that is different from that for any different vehicle in which a reckless driving operation is not determined to take place.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a U.S. National Phase Application under 35 U.S.C. 371 of International Application No. PCT/JP2014/001951 filed on Apr. 3, 2014 and published in Japanese as WO 2014/167810 A1 on Oct. 16, 2014. This application is based on and claims the benefit of priority from Japanese Patent Application No. 2013-081530 filed on Apr. 9, 2013. The entire disclosures of all of the above applications are incorporated herein by reference.

TECHNICAL FIELD

The present disclosure relates to a technology that uses inter-vehicle communication to notify a driver of other reckless vehicles around a driver's vehicle.

BACKGROUND ART

The prior art technology as disclosed in patent literature 1 uses inter-vehicle communication to acquire a position or a travel direction of a vehicle (namely a nearby vehicle) existing around a vehicle and display the position or the travel direction so as to overlap with a map image.

PRIOR ART LITERATURES

Patent Literature

Patent Literature 1: JP 2004-077281 A

SUMMARY OF INVENTION

However, the technology disclosed in patent literature 1 just displays the position or the travel direction of the nearby vehicle and cannot report whether a driver of the nearby vehicle drives the nearby vehicle safely or recklessly. The driver can take action such as keeping an inter-vehicular distance longer than normal if he or she can know that the nearby vehicle indicates reckless driving.

It is an object of the present disclosure to provide a reckless-vehicle reporting apparatus that can report to a driver of a vehicle whether a nearby vehicle is driven recklessly, a program product for reporting reckless vehicles, and a method for reporting reckless vehicles.

To achieve the object, according to a first example of the present disclosure, a reckless-vehicle reporting apparatus is provided as follows. The reckless-vehicle reporting apparatus is mounted in a vehicle and wirelessly communicates data with a different reckless-vehicle reporting apparatus in each of a plurality of different vehicles different from the vehicle. The different reckless-vehicle reporting apparatus is identical to the reckless-vehicle reporting apparatus in function. The reckless-vehicle reporting apparatus includes a position detection unit that detects a position of the vehicle, and an in-vehicle communicator that transmits a position data indicating a position of the vehicle and receives a position data indicating a position of each of the different vehicles. Further; the reckless-vehicle reporting apparatus includes (i) a mark display processor that displays a mark indicating the position of each of the different vehicles on a display based on the received position data of each of the different vehicles; (ii) a determination information acquisition section that acquires determination information that is used to determine whether a reckless driving operation takes place in the vehicle or not; (iii) a transmission control section that transmits the determination information acquired by the determination information acquisition section via the in-vehicle communicator; (iv) a reception control section that receives determination information from each of the different vehicles via the in-vehicle communicator, the determination information received from each of the different vehicles being used to determine whether a reckless driving operation takes place in each of the different vehicles or not; and (v) a reckless-vehicle determination section that determines whether a reckless driving operation takes place in each of the different vehicles based on the determination information of each of the different vehicles received by the reception control section. Furthermore, the reckless-vehicle reporting apparatus includes a reckless-vehicle display processor that displays the mark indicating the position of a target different vehicle in a first display mode. The target different vehicle is the different vehicle in which the reckless driving operation is determined to take place by the reckless-vehicle determination section. The first display mode is different from a second display mode that is used for the mark indicating the position of each of the different vehicles in which the reckless driving operation is not determined to take place.

According to the configuration, the reckless-vehicle determination section of the reckless-vehicle reporting apparatus mounted on a vehicle determines whether or not a different vehicle indicates reckless driving, based on determination information, which is about the different vehicle and transmitted from the different vehicle. When a target different vehicle is determined to indicate reckless driving, the target different vehicle is displayed on a display in a display mode (display form) different from a display mode used for a different vehicle that is not determined to indicate reckless driving. Viewing the display, a driver of a vehicle can identify whether or not a different vehicle traveling around the vehicle indicates reckless driving. The driver of the vehicle can be notified whether or not a nearby vehicle indicates reckless driving.

In addition, according to a second example of the present disclosure, a reckless-vehicle reporting program product is provided as follows. That is, the product is stored in a non-transitory computer-readable medium. The product includes instructions to cause a computer to function as the determination information acquisition section, the transmission control section, the reception control section, the mark display processor, the reckless-vehicle determination section, and the reckless-vehicle display processor, all of which are included in the reckless-vehicle reporting apparatus according to the above first example.

Furthermore, according to a third example of the present disclosure, a reckless-vehicle reporting method is provided as follows. That is, the method is executed by a computer to achieve functions as the determination information acquisition section, the transmission control section, the reception control section, the mark display processor, the reckless-vehicle determination section, and the reckless-vehicle display processor, all of which are included in the reckless-vehicle reporting apparatus according to the above first example.

DESCRIPTION OF EMBODIMENTS

An embodiment of the disclosure will be described with reference toFIGS. 1 through 10.FIG. 1is a diagram illustrating a schematic configuration of an inter-vehicle communication system (hereinafter referred to as a reckless vehicle reporting system)100using a reckless-vehicle reporting apparatus1according to the disclosure. The reckless vehicle reporting system100includes the reckless-vehicle reporting apparatus1that is used based on one-to-one correspondence to each of several vehicles. The several vehicles include vehicle A and at least two or more vehicles B though unshown inFIG. 1. Vehicle A is also referred to as a subject vehicle or simply a vehicle. Vehicle B is also referred to as a different vehicle. The relationship between the subject vehicle and the different vehicle is relative. Suppose that one vehicle B is the subject vehicle. Then, vehicle A is the different vehicle against vehicle B. A vehicle mounted with an apparatus is also referred to as a host vehicle for the apparatus.

The following describes a schematic configuration of the reckless-vehicle reporting apparatus1with reference toFIG. 2.FIG. 2is a diagram illustrating a schematic configuration of the reckless-vehicle reporting apparatus1. As illustrated inFIG. 2, the reckless-vehicle reporting apparatus1includes a portable terminal2and a communicator3.

The portable terminal2acquires data to be transmitted to a different vehicle (hereinafter simply referred to as the nearby vehicle) existing in an area around the subject vehicle mounted with the portable terminal2. The portable terminal2also reports data received from the nearby vehicle to a driver of the subject vehicle using a display27. The area around the subject vehicle signifies a range in which the communicator3(to be described) is capable of wireless communication. The portable terminal2may be available as a multi-functional mobile telephone such as a publicly known smartphone. The portable terminal2is temporarily fixed in a vehicle compartment so that the subject vehicle's driver can visually check the display27of the portable terminal2. More favorably, the embodiment previously provides the portable terminal2with installation disposition (orientation of the portable terminal2with reference to a front-back direction of the subject vehicle or an angle of the terminal with reference to a horizontal plane) of the portable terminal2with reference to the subject vehicle. The portable terminal2is installed at a position corresponding to the installation disposition. For example, the portable terminal2is installed so that the display27is oriented to a driver's seat at 110 degrees with reference to the horizontal plane and a mapping component of the portable terminal2in a vertical direction on the horizontal plane corresponds to the front-back direction of the subject vehicle. The installation disposition of the portable terminal2in relation to the vehicle is not limited thereto. A driver is allowed to configure the installation disposition.

To provide a function as the above device, the portable terminal2includes an in-terminal Bluetooth (registered trademark, hereinafter abbreviated as BT) communication unit21, a detector22, memory26, the display27, and an in-terminal control circuit28.

To exchange information, the in-terminal BT communication unit21includes a transmitting and receiving antenna and performs Bluetooth-compliant communication (hereinafter referred to as BT communication) with the communicator3of the subject vehicle. The embodiment uses the BT communication as communication between the portable terminal2and the communicator3but is not limited thereto. The communication may be configured to be wireless or wired. The wireless communication may comply with a short-range communication standard such as ZigBee (registered trademark) or a wireless LAN standard such as IEEE802.11. The wired communication may be available as USB communication. The in-terminal BT communication unit21is also referred to as a different communication unit or an additional communication unit.

The detector22acquires various types of data to generate information used to determine whether or not the subject vehicle is driven safely. According to the embodiment, the detector22includes a GPS receiver221, an acceleration sensor222, and a gyro sensor223. The GPS receiver221receives a radio wave from a GPS (Global Positioning System) satellite. The acceleration sensor222detects an acceleration acting on the terminal. The gyro sensor223detects an angular velocity or an angle acting on the terminal.

The memory26is provided as electrically rewritable, nonvolatile memory. The memory26stores map data for route guidance and a program4that allows a portable terminal such as a publicly known multi-functional mobile telephone to operate as the portable terminal2according to the embodiment. The memory26may be available as a removable storage medium such as an SD card that can be removed from the portable terminal2. The memory26does not erase saved data unless a vehicle driver explicitly issues an instruction to erase the data. The program4that allows a publicly known portable terminal to operate as the portable terminal2according to the embodiment may be installed in a storage area of ROM included in the in-terminal control circuit28(to be described later). The program4may be also referred to as a reckless-vehicle reporting program product.

The display27displays text or an image based on a signal input from the in-terminal control circuit28. The display27is capable of full-color display and can use a TFT liquid crystal display or an organic EL display.

The in-terminal control circuit28is configured as an ordinary computer and internally contains a widely known CPU; memory devices such as ROM, RAM, EEPROM; an I/O device; and a bus line connecting these components (none illustrated). The in-terminal control circuit28performs various processes based on various types of information input from the in-terminal BT communication unit21and the detector22while the CPU executes a program previously stored in ROM or the memory26. The in-terminal control circuit28may be configured as hardware such as one or more IC devices.

As illustrated inFIG. 3, the in-terminal control circuit28includes function blocks to process data to be transmitted to the nearby vehicle. The function blocks include a vehicle data computation unit281, internal memory282, and a transmission control section283. The in-terminal control circuit28includes function blocks to process data received from the nearby vehicle. The function blocks include a reception control section284, a vehicle identification section285, a reckless-vehicle determination section286, a map image drawing section287, a nearby vehicle display section288, and a recklessness determination continuation section289. The internal memory282is provided as electrically rewritable memory such as RAM or EEPROM. For convenience sake, the following omits the description of functions that are included in an ordinary multi-functional mobile telephone but are unnecessary for the description of the disclosure.

The vehicle data computation unit281computes various data (vehicle data) concerning a travel state of the subject vehicle from various sensor data successively detected by the detector22and stores the data in the internal memory282. The vehicle data computed by the vehicle data computation unit281includes a position of the portable terminal2(namely, a position of the subject vehicle), a travel speed of the subject vehicle, acceleration acting on the subject vehicle, a travel direction (hereinafter referred to as an orientation angle) of the subject vehicle, and an orientation angle speed. The embodiment does not necessarily need all these types of data. At least one of the data may be contained in order to acquire data to determine whether or not the driving is safe. For example, the vehicle data may include only the position and the acceleration of the subject vehicle. The vehicle data computation unit281includes function blocks to acquire the vehicle data as illustrated inFIG. 4. The function blocks include an installation disposition detection unit281A, an acceleration computation unit281B, a speed computation unit281C, an orientation angle speed computation unit281D, an orientation angle computation unit281E, and a position acquisition unit281F. The vehicle data computation unit281can also function as a determination information acquisition section. The vehicle data is also referred to as determination information.

The installation disposition detection unit281A detects an installation disposition of the portable terminal2with reference to the subject vehicle. The embodiment uses a predetermined value for the installation disposition with reference to the subject vehicle but is not limited thereto. When the portable terminal2includes the acceleration sensor222and the gyro sensor223, the installation disposition detection unit281A can use a publicly known technology to detect the terminal's orientation or tilt against the horizontal plane from the sensor data. The installation disposition detection unit281A detects a front-back direction of the subject vehicle from chronological data about subject vehicle positions computed by the position acquisition unit281F (to be described) to compute the terminal orientation with reference to the front-back direction. To detect the front-back direction of the subject vehicle, the installation disposition detection unit281A detects a straight-road interval to travel using chronological data about subject vehicle positions computed by the position acquisition unit281F and assumes the direction of movement to travel the straight-road interval to be the front-back direction of the subject vehicle. The installation disposition detection unit281A detects an installation disposition of the portable terminal2with reference to the subject vehicle. Consequently, the installation disposition detection unit281A can find the acceleration acting on the front-back direction of the subject vehicle using a sensor value such as the acceleration acting on the terminal.

The acceleration computation unit281B successively computes a component of the acceleration (hereinafter simply assumed to be the acceleration) acting on the terminal corresponding to the front-back direction of the subject vehicle from the installation disposition detected by the installation disposition detection unit281A. A positive value is used to express the acceleration generated in a travel direction. A negative value is used to express the acceleration in a deceleration direction. The embodiment computes only a component of the acceleration acting on the terminal corresponding to the front-back direction of the subject vehicle. The embodiment may additionally compute a component of the acceleration acting on the terminal corresponding to a vehicle width direction. The acceleration computation unit281B can be referred to as an acceleration acquisition unit.

The speed computation unit281C successively computes a travel speed of the subject vehicle by integrating the acceleration in the vehicle's front-back direction computed by the acceleration computation unit281B. The speed computation unit281C is also referred to as a travel speed acquisition unit. The orientation angle speed computation unit281D successively computes an orientation angle speed (rad/sec) acting on the subject vehicle based on the installation disposition detected by the installation disposition detection unit281A and a change in the angular velocity detected by the gyro sensor223. The orientation angle speed computation unit281D is also referred to as an orientation angle speed acquisition unit. The orientation angle computation unit281E computes a change in the terminal angle by integrating the angular velocity detected by the gyro sensor223. The orientation angle computation unit281E further computes an orientation angle (rad) of the subject vehicle based on the relative relationship between the terminal orientation detected by the installation disposition detection unit281A and the subject vehicle orientation.

The position acquisition unit281F successively detects the subject vehicle position based on information acquired from the sensors including the acceleration sensor222and the gyro sensor223in addition to the information about the subject vehicle position received by the GPS receiver221. The sensors are prone to errors of different properties and are therefore configured to complement each other to detect the subject vehicle position. Part of the sensors may be used depending on accuracies of the sensors. A sensor other than the ones mentioned above may be used. The position acquisition unit281F may use only the GPS receiver221to detect the subject vehicle position. The subject vehicle position is expressed in the latitude and the longitude. The position acquisition unit281F or GPS receiver221is also referred to as a position detection unit.

The method of computing values such as the acceleration is not limited to the one described above. The speed computation unit281C can compute the travel speed by computing a travel distance per unit time based on chronologically marked main vehicle positions. The acceleration computation unit281B can process the acceleration corresponding to a value resulting from temporal differentiation of the successively computed travel speed.

The orientation angle computation unit281E can find an orientation angle by computing a direction of an approximate line found by the least-square method based on chronologically marked positions. The portable terminal2may include a geomagnetic sensor and may be able to use a detection result from the geomagnetic sensor. In such a case, the orientation angle computation unit281E can find an orientation angle of the subject vehicle using a detection result from the geomagnetic sensor. The orientation angle speed computation unit281D may find an orientation angle speed using temporal differentiation of an orientation angle successively computed by the orientation angle computation unit281E.

The vehicle data computed by vehicle data computation unit281is given information (time stamp) about the time of the computation and is stored in the internal memory282. Storing new data in the internal memory282may exceed the allocated memory capacity. In such a case, data already stored in the internal memory282may be erased from the earliest data. Alternatively, stored vehicle data may be erased when the data continues to be stored over a specified time period.

The transmission control section283provides control to transmit vehicle data stored in the internal memory282to the communicator3via the in-terminal BT communication unit21. The transmission control section283reads vehicle data stored in the internal memory282when receiving an acquisition request to acquire information about the subject vehicle from the communicator3of the subject vehicle via the in-terminal BT communication unit21. The transmission control section283transmits the read vehicle data to the communicator3via the in-terminal BT communication unit21. Basically, the transmission control section283reads the most recent data (corresponding to the newest time stamp). Further, the transmission control section283may read and transmit vehicle data corresponding to several time points in the past from the most recent vehicle data. As will be described in detail later, an inter-vehicle transmission control section331transmits vehicle data to a nearby vehicle while the vehicle data is assumed to be vehicle information provided with an identification ID to identify the vehicle.

The communicator3of the subject vehicle receives the vehicle information about the nearby vehicle from the nearby vehicle. The reception control section284receives the vehicle information about the nearby vehicle via the in-terminal BT communication unit21. Similarly to the vehicle information about the subject vehicle, the vehicle information about the nearby vehicle includes an identification ID, a vehicle position, an orientation angle, a travel speed, an acceleration, and an orientation angle speed.

The vehicle identification section285determines whether or not the vehicle information about the nearby vehicle is transmitted from the same vehicle or a different vehicle, based on the identification ID contained in the vehicle information about the nearby vehicle. The vehicle identification section285classifies the vehicle information according to vehicles and stores the vehicle information in the internal memory282.

Based on the vehicle information about the nearby vehicle, the reckless-vehicle determination section286checks each nearby vehicle to determine whether or not the nearby vehicle (hereinafter referred to as a reckless vehicle) indicates reckless driving. A process to determine whether or not the nearby vehicle is a reckless vehicle will be described in detail later.

The map image drawing section287reads map data near the current subject vehicle position from the memory26and draws a map image so that the subject vehicle is displayed at the center of a screen. The range of map data read from the memory26depends on the current subject vehicle position and the display scale predetermined for a map image.

The nearby vehicle display section288draws a mark representing the position and the orientation angle identified by the vehicle identification section285for each nearby vehicle. The mark is drawn so as to overlap with the map image drawn by the map image drawing section287. A nearby vehicle determined to be a reckless vehicle by the reckless-vehicle determination section286is displayed with a mark whose display mode (display form) such as color or shape differs from that of a vehicle (hereinafter referred to as a normal vehicle) not determined to be a reckless vehicle. The purpose is to make a distinction between the reckless vehicle and the normal vehicle. The display mode to distinguish the reckless vehicle from the normal vehicle can use colors, shapes, blinking, a variation of colors, text, and a combination of these. A mark representing the reckless vehicle is displayed nearer to the driver than the normal vehicle. This enables to display marks for reckless vehicles without hiding the marks even if marks for nearby vehicles are densely displayed to overlap.

The mark representing the vehicle position of each nearby vehicle is moved each time the vehicle information about each nearby vehicle is received and the vehicle position is updated. For convenience sake, the embodiment provides a function to display reckless vehicles as a reckless vehicle display section288A. The nearby vehicle display section288is also referred to as a mark display processor. The reckless vehicle display section288A is also referred to as a reckless vehicle display processor.

When the reckless-vehicle determination section286determines the nearby vehicle to be a reckless vehicle, the recklessness determination continuation section289continues to determine the nearby vehicle to be a reckless vehicle while performing inter-vehicle communication with the nearby vehicle. This is because a vehicle having experience in reckless driving operation is highly likely to repeat reckless driving operation even if the vehicle temporarily ceases the reckless driving operation. The recklessness determination continuation section289can allow a driver of subject vehicle A to identify a vehicle that is highly likely to repeat reckless driving operation though the vehicle is not performing reckless driving operation at the present. A reckless vehicle determination process (to be described) is not performed on a vehicle once determined to be a reckless vehicle while the recklessness determination continuation section289continues to determine that the vehicle is a reckless vehicle.

A condition to return the reckless vehicle to the normal vehicle is satisfied when the reckless vehicle exits from a range capable of wireless communication with the subject vehicle and the vehicle information from the reckless vehicle cannot be received for a specified time period (e.g., 30 seconds) or longer. Another embodiment may return the reckless vehicle to the normal vehicle when a specified time period (e.g., one minute) elapses after the vehicle is determined to be a reckless vehicle.

Returning toFIG. 2, the communicator3exchanges information with the communicator3of the nearby vehicle based on inter-vehicle communication. The communicator3is not limited to being mounted on a vehicle. The communicator3may be portable and may be carried by a driver into the vehicle. The communicator3includes an in-communicator BT communication unit31, an inter-vehicle communication unit32, and an in-communicator control circuit33. The communicator3is also referred to as an in-vehicle communicator.

The in-communicator BT communication unit31includes a transmitting and receiving antenna and performs BT communication with the portable terminal2of the subject vehicle to exchange information. The in-communicator BT communication unit31is also referred to as a different communication unit or an additional communication unit.

The inter-vehicle communication unit32includes a transmitting and receiving antenna and performs inter-vehicle communication with the communicator3of the nearby vehicle to exchange information based on wireless communication without using a telephone network. A range to perform the inter-vehicle communication depends on frequency bands used for the wireless communication. When the wireless communication uses a radio wave in 700 MHz band, the inter-vehicle communication is performed with the communicator3of the nearby vehicle existing within a radius of approximately one kilometer around the subject vehicle as a center. When the wireless communication uses a radio wave in 5.9 GHz band, the inter-vehicle communication is performed with the communicator3of the nearby vehicle existing within a radius of approximately 500 meters around the subject vehicle as a center. The inter-vehicle communication unit32transmits information on a transmission cycle (e.g., 100 milliseconds) according to an instruction from the in-communicator control circuit33.

The in-communicator control circuit33is configured as an ordinary computer and internally contains a widely known CPU; memory devices such as ROM, RAM, EEPROM; an I/O device; and a bus line connecting these components (none illustrated). The in-communicator control circuit33performs various processes based on various types of information input from the in-communicator BT communication unit31and the inter-vehicle communication unit32while the CPU executes a program previously stored in the ROM. The in-communicator control circuit33may be configured as hardware such as one or more IC devices.

As illustrated inFIG. 5, the in-communicator control circuit33includes function blocks such as an inter-vehicle transmission control section331, an inter-vehicle reception control section332, a BT transmission control section333, and a BT reception control section334.

The BT reception control section334receives vehicle data transmitted from the portable terminal2via the in-communicator BT communication unit31. The inter-vehicle transmission control section331generates vehicle information about the subject vehicle from the vehicle data received by the BT reception control section334and transmits the vehicle information via the inter-vehicle communication unit32.

The inter-vehicle reception control section332receives vehicle information about the nearby vehicle transmitted from the communicator3of the nearby vehicle via the inter-vehicle communication unit32. The BT transmission control section333transmits the vehicle information received by the inter-vehicle reception control section332to the portable terminal2of the subject vehicle via the in-communicator BT communication unit31.

With reference to a flowchart inFIG. 6, the following describes a vehicle information transmission process the in-communicator control circuit33of the communicator3performs to transmit the subject vehicle information to the nearby vehicle.

It is noted that a flowchart or the processing of the flowchart in the present application includes sections (also referred to as steps), each of which is represented, for instance, as S10. Further, each section can be divided into several sub-sections while several sections can be combined into a single section. Furthermore, each of thus configured sections can be also referred to as a device or module. Each or any combination of sections explained in the above can be achieved as (i) a software section in combination with a hardware unit (e.g., computer) or (ii) a hardware section, including or not including a function of a related apparatus; furthermore, the hardware section (e.g., integrated circuit, hard-wired logic circuit) may be constructed inside of a microcomputer.

The flowchart inFIG. 6can start when the communicator3and the portable terminal2are powered on.

At S10, the BT reception control section334receives vehicle data and proceeds to S12. During the vehicle data reception process at S10, the BT reception control section334transmits an acquisition request for vehicle data to the portable terminal2via the in-communicator BT communication unit31. In response to the acquisition request, the BT reception control section334receives vehicle data returned from the portable terminal2via the in-communicator BT communication unit31.

According to the embodiment, the communicator3transmits an acquisition request for vehicle data to the portable terminal2. The BT reception control section334receives the vehicle data returned in response to the acquisition request. However, the embodiment is not limited thereto. The portable terminal2may transmit the most recent vehicle data stored in the internal memory282at a specified time interval. The BT reception control section334may successively receive the transmitted vehicle data.

At S12, the inter-vehicle transmission control section331performs a vehicle information generation process and proceeds to S14. The vehicle information generation process at S12supplies the vehicle data received by the BT reception control section334with an identification number to identify a vehicle and generates vehicle information to be transmitted during the inter-vehicle communication. As the identification number, the embodiment uses a device ID uniquely assigned to the communicator3, but is not limited thereto. The identification number may be available as a vehicle ID assigned to each vehicle or a portable terminal ID (e.g., product number) assigned to the portable terminal2as well as the device ID.

According to the embodiment, the portable terminal2generates vehicle data. The inter-vehicle transmission control section331performs the process to supply the subject vehicle information with the device ID. However, the embodiment is not limited thereto. The inter-vehicle transmission control section331may receive sensor values from various sensors included in the portable terminal2. The inter-vehicle transmission control section331may generate the subject vehicle information based on the sensor values. The communicator3may include at least a satellite positioning system receiver such as the GPS receiver221. The receiver can detect a position of the communicator3for the subject vehicle. In such a case, the subject vehicle information may be generated based on the detected position. An orientation angle of the subject vehicle may be computed based on the position of the communicator3for the subject vehicle using the same method as that used to compute an orientation angle from chronological data for subject vehicle positions. The communicator3may be connected to a yaw rate sensor or a vehicle speed sensor (none illustrated) included in the subject vehicle via a CAN bus and may be able do acquire sensor values from the various sensors. In such a case, the vehicle information may be generated based on the sensor values.

At S14, the inter-vehicle transmission control section331performs a vehicle information transmission process and proceeds to S16. The vehicle information transmission process at S14transmits the vehicle information about the subject vehicle generated by the vehicle information generation process to the nearby vehicle via the inter-vehicle communication unit. The vehicle information transmission process transmits the vehicle information on a cycle such as 100 ms in accordance with the transmission cycle of the inter-vehicle communication on the communicator3.

The vehicle information transmission process terminates the flow if the vehicle information transmission process reaches termination timing at S16(S16YES). The vehicle information transmission process returns to S10and repeats the flow if the vehicle information transmission process does not reach the termination timing at S16(S16NO). An example of the timing to terminate the vehicle information transmission process is to power off at least one of the communicator3and the portable terminal2.

With reference to a flowchart inFIG. 7, the following describes a vehicle information reception process the in-communicator control circuit33of the communicator3performs to receive the nearby vehicle information. Similarly to the vehicle information transmission process inFIG. 6, the flowchart inFIG. 7can start when the communicator3and the portable terminal2are powered on.

At S20, the inter-vehicle reception control section332performs the vehicle information reception process and proceeds to S22. The vehicle information reception process at S20receives vehicle information transmitted from the nearby vehicle via the inter-vehicle communication unit. The nearby vehicle information is received successively.

At S22, the BT transmission control section333performs a transfer process and proceeds to S24. The transfer process at S22transmits the nearby vehicle information to the portable terminal2via the in-communicator BT communication unit31. The vehicle information received at S20is successively transferred to the portable terminal2at S22. However, the configuration is not limited thereto. A specified transfer cycle (100 milliseconds) may be defined. The nearby vehicle information received during this cycle may be transferred at a time.

The vehicle information reception process terminates the flow if the vehicle information reception process reaches termination timing at S24(S24YES). The vehicle information reception process returns to S20and repeats the flow if the vehicle information reception process does not reach the termination timing at S24(S24NO). An example of the timing to terminate the vehicle information reception process is to power off at least one of the communicator3and the portable terminal2.

With reference to a flowchart inFIG. 8, the following describes a reckless vehicle determination process the reckless-vehicle determination section286performs to determine whether or not the nearby vehicle is a reckless vehicle. The process corresponding to the flowchart inFIG. 8is performed on each nearby vehicle when the nearby vehicle information is received. For convenience sake, a nearby vehicle targeted at the reckless vehicle determination process is referred to as a target vehicle or another target vehicle to be distinguished from the other nearby vehicles.

At S30, the process determines whether or not the acceleration contained in the target vehicle information is greater than specified threshold value Ath. Threshold value Ath is defined as 0.6 G assuming that 1G=9.81 m/sec/sec. Threshold value Ath may be set to another value (e.g., 0.5 G) and may be found as the vehicle acceleration assumed to be dangerous from observation data in the past. Different threshold values Ath may be provided for vehicle types if a vehicle type can be acquired from the vehicle information. Threshold value Ath may be set to 0.6 G for a passenger car, 0.7 G for a van, 0.5 G for a truck carrying a load of less than 4 tons, and 0.45 G for a truck or a bus carrying a load ranging from 4 to 10 tons. These values may be appropriately designed. The process results in YES at S30and proceeds to S34if the target vehicle acceleration is greater than threshold value Ath at S30. The process results in NO at S30and proceeds to S31if the target vehicle acceleration is smaller than or equal to threshold value Ath.

At S31, the process determines whether or not a travel speed of the target vehicle is greater than specified threshold value Vth. Threshold value Vth may correspond to a legal speed for a road the target vehicle is traveling. The type of a road the target vehicle is traveling is acquired from map data stored in the memory26. The legal speed can be determined according to the road type. The process results in YES at S31and proceeds to S34if the travel speed of the target vehicle is greater than Vth at S31. The process results in NO at S31and proceeds to S32if the travel speed of the target vehicle is smaller than or equal to threshold value Vth.

At S32, the process determines whether or not the travel speed of the target vehicle is greater than the sum of an average value (an average travel speed or an average speed) of travel speeds of other nearby vehicles traveling around (mainly forward and backward of) the target vehicle and a specified threshold value (Wth). Threshold value Wth may be set to 10 km/h as an example. Threshold value Wth may be set to other values such as 5 km/h or may be set a value depending on the average speed (such as 20% of the average speed).

Another vehicle traveling around the target vehicle is defined as being existent within 50 m from the target vehicle in the front-back direction and having an orientation angle that causes a difference (orientation angle difference) of within ±10 degrees from the orientation angle of the target vehicle. The range around the target vehicle in the front-back direction is not limited to 50 m. The distance may be proportional to a travel speed of the target vehicle. The orientation angle condition is provided in consideration of the following. At an intersection, a stopping vehicle and a traveling vehicle are present concurrently. An improper average speed is computed if all the vehicles are assumed to be a population. To solve this, the population used to compute an average speed is replaced by a nearby vehicle whose orientation angle approximately equals the orientation angle of the target vehicle. This can eliminate a noise due to a vehicle that waits for a traffic light or travels the opposite lane at the intersection. An average speed can be computed more accurately. The embodiment uses an orientation angle difference of 10 degrees between a vehicle as the population to compute an average speed and the target vehicle. The other values (e.g., 5 degrees) may be used.

The front-back direction is not limited to the straight front or rear of the target vehicle and also covers the range diagonally forward and backward. The embodiment is not limited thereto. As a more favorable mode, a vehicle traveling the same lame as the target vehicle is used as the population to compute an average speed. This enables to compute an average speed more accurately. This is because the same road may contain different lanes where vehicles travel at different speeds. To determine whether or not the same lane is traveled, the target vehicle is extended along its front-back direction to compute a line based on the vehicle position and the orientation angle of the target vehicle. A distance is found between the line and the nearby vehicle for the target vehicle. The vehicles are determined to travel the same lane if the shortest distance is within one meter. Other publicly known technologies may be used to determine whether or not the same lane is traveled.

The process results in YES at S32and proceeds to S34if the travel speed of the target vehicle is greater than the sum of an average speed of vehicles traveling around the target vehicle and the specified threshold value (Wth) at S32. The process results in NO at S32and proceeds to S33if the travel speed of the target vehicle is smaller than or equal to the sum of an average speed of vehicles traveling around the target vehicle and the specified threshold value (Wth). The process also results in NO at S32and proceeds to S33if no vehicle is found around the target vehicle and an average speed cannot be computed.

At S33, the process determines whether or not the orientation angle speed of the target vehicle is greater than specified threshold value Yth. According to the embodiment, threshold value Yth is set to 0.07 rad/sec (≈4 deg/sec) or may be specified otherwise. A vehicle orientation angle speed assumed to be dangerous may be found from the observation data in the past. The process results in YES at S33and proceeds to S34if the orientation angle speed of the target vehicle is greater than specified threshold value Yth at S33. The process results in NO at S33and proceeds to S35if the orientation angle speed of the target vehicle is smaller than or equal to specified threshold value Yth.

At S34, the process determines that the target vehicle is a reckless vehicle. The reckless vehicle determination process then terminates. The reckless-vehicle determination section286stores the identification ID for the nearby vehicle determined to be a reckless vehicle in the internal memory282so as to be distinguished from the identification ID of the normal vehicle. This enables to explicitly identify the reckless vehicle.

At S35, the process determines that the target vehicle is a normal vehicle. The reckless vehicle determination process then terminates. The reckless-vehicle determination section286stores the identification ID for the nearby vehicle determined to be a normal vehicle in the internal memory282so that the normal vehicle can be explicitly identified.

With reference to a flowchart inFIG. 9, the following describes a nearby vehicle display process that allows the display27to display nearby vehicle information such as a nearby vehicle position or determination whether or not the nearby vehicle is a reckless vehicle. The flowchart inFIG. 9starts when the communicator3and the portable terminal2are powered on.

At S40, the process performs a position acquisition process and proceeds to S42. During the position acquisition process at S40, the map image drawing section287reads the subject vehicle position information corresponding to the newest time stamp (namely, the most recent subject vehicle position information) from the subject vehicle position information stored in the internal memory282.

At S42, the map image drawing section287performs a map data acquisition process and proceeds to S44. This map data acquisition process at S42reads map data around the current main vehicle position from the memory26. The range of map data read from the memory26depends on the current main vehicle position and the display scale predetermined for a map image.

At S44, the map image drawing section287performs a map image drawing process and proceeds to S46. The map image drawing process at S42generates a map image from the map data read at S41so that the current subject vehicle position is located approximately at the center of the screen.

At S46, the nearby vehicle display section288performs a nearby vehicle drawing process and proceeds to S48. During the nearby vehicle drawing process at S46, the nearby vehicle display section288draws a mark representing the position and the orientation angle identified by the vehicle identification section285for each nearby vehicle. The mark is drawn so as to overlap with the map image generated at S46. A nearby vehicle determined to be a reckless vehicle is displayed with a mark whose display mode such as color or shape differs from that of a normal vehicle.

The nearby vehicle display process terminates the flow if the nearby vehicle display process reaches termination timing at S48(S46YES). The nearby vehicle display process returns to S40and repeats the flow (to successively update images) if the nearby vehicle display process does not reach the termination timing (S46NO). An example of the timing to terminate the nearby vehicle display process is to disconnect the portable terminal2from the communicator3or to power off the communicator3.

FIG. 10illustrates a display screen of the display27where the processes are performed. Reference symbol A inFIG. 10represents a subject vehicle. Reference symbols B1through B6represent nearby vehicles for the subject vehicle. Each of A and B1through B6includes the reckless-vehicle reporting apparatus1that is present within a range capable of wireless communication with the communicator3. The example uses normal vehicles B1through B4and reckless vehicles B5and B6.

Nearby vehicle B5excessively approaches normal vehicle B1and causes sudden braking. The process results in YES at S30of the flowchart inFIG. 8and nearby vehicle B5is therefore assumed to be a reckless vehicle. Nearby vehicle B6turns in the intersection while the deceleration is insufficient. The orientation angle speed exceeds threshold value Yth and the process results in YES at S33.

As illustrated inFIG. 10, normal vehicles B1through B4are represented as isosceles triangles. The vehicles travel in the direction toward an apex of the isosceles triangle. The orientation of the isosceles triangle represents the orientation angle of the vehicle. The marks representing normal vehicles B1through B4are displayed in gray, for example.

Subject vehicle A is located near the center (slightly downward from the center) of the screen. Subject vehicle A is displayed with a mark different from the normal vehicle and the reckless vehicle so as to be distinguishable from the nearby vehicle. The subject vehicle can be displayed in blue, for example. Reckless vehicles B5and B6are represented as isosceles triangles colored in yellow, orange, or red so as to be identified at a glance. An exclamation mark may be displayed inside. The embodiment uses an isosceles triangle as the mark to indicate the vehicle's position and orientation angle. Graphics such as an arrow may be also used.

Viewing the screen as illustrated inFIG. 10, a driver of subject vehicle A can recognize at a glance whether or not the nearby vehicle indicates reckless driving. Suppose that the nearby vehicle traveling ahead of the subject vehicle is a reckless vehicle. The driver can take action such as keeping an inter-vehicular distance longer than usual and can be aware of safer driving.

The embodiment provides the following operations and effects. According to the configuration, a different vehicle transmits the determination information about the different vehicle itself. The portable terminal2determines whether or not the different vehicle (reckless vehicle) indicates reckless driving. The reckless vehicle is displayed in the display mode that differs from the other non-reckless vehicles. Viewing the display, the driver of the subject vehicle can recognize whether or not the different vehicle traveling around indicates reckless driving. The driver of the subject vehicle can be notified whether or not the nearby vehicle indicates reckless driving.

According to the embodiment, the subject vehicle determines whether or not the nearby vehicle is a reckless vehicle. Further, the nearby vehicle as a transmission side may determine whether or not the nearby vehicle itself is a reckless vehicle. The nearby vehicle may transmit a determination result to the subject vehicle. However, the subject vehicle is uncertain about criteria (various threshold values described above) to determine a reckless vehicle when the transmission side itself determines whether or not it is a reckless vehicle. This may degrade reliability of a determination result transmitted from the nearby vehicle.

According to the embodiment, however, the subject vehicle as a reception side determines whether or not the nearby vehicle is a reckless vehicle. This can improve reliability of determining whether or not the nearby vehicle is a reckless vehicle. The driver of the subject vehicle may be able to configure various threshold values (Ath, Vth, Wth, and Yth) used to determine whether or not a different vehicle indicates reckless driving. This enables to determine reckless vehicles according to the driver's preference.

The inter-vehicle communication uses a finite region. A communication region may be insufficient due to transmission of a determination result as well as the vehicle information such as acceleration. However, the inter-vehicle communication previously ensures a region used for the vehicle information such as acceleration. There is no need to worry about insufficiency of the communication region. According to the embodiment, the nearby vehicle transmits its vehicle information. The subject vehicle as the reception side determines whether or not the nearby vehicle is a reckless vehicle. This enables to more efficiently use the communication region and more smoothly actualize the embodiment.

According to the embodiment, the reckless vehicle determination process at S32inFIG. 8determines whether or not the target vehicle is a reckless vehicle, based on comparison between a travel speed of the target vehicle and an average value (average speed) of travel speeds of the other nearby vehicles traveling around the target vehicle. However, the configuration is not limited thereto. Other statistic criteria may be used to determine whether or not the target vehicle is a reckless vehicle. An example is the normal distribution whose population uses travel speeds of other nearby vehicles traveling around the target vehicle. The target vehicle may be determined to be a reckless vehicle if a travel speed of the target vehicle exceeds a range between −1 σ and +1 σ.

The embodiment classifies nearby vehicles into two grades such as a normal vehicle and a reckless vehicle. However, the configuration is not limited thereto. The extent of recklessness differs between reckless vehicles depending on whether a nearby vehicle travels 10 km/h or 30 km/h higher than threshold value Vth used to determine reckless driving operation based on travel speeds. Threshold value Vth for travel speeds may be classified into more grades. The extent of recklessness may be evaluated based on several grades.

The reckless vehicle display section288A favorably uses different display modes corresponding to the extent of recklessness for a nearby vehicle when several grades are used to determine the extent of recklessness for reckless vehicle. When the extent of recklessness is greater, the display mode may enable the display to be colored in more vivid red or cause blinking at shorter intervals to be more apparent to a subject vehicle driver. When the extent of recklessness is lesser, the display mode may enable the display to be more approximate to a normal vehicle. The extent of recklessness for reckless vehicle may be decreased as time proceeds. The nearby vehicle display section288may approximate the display mode to a normal vehicle mark according to the extent of recklessness. The modification evaluates the extent of recklessness in terms of travel speeds based on several grades. Further, the extent of recklessness may be similarly evaluated using grades of threshold values in terms of accelerations or orientation angle speeds.

The reckless-vehicle determination section286may use the vehicle information about the subject vehicle to determine whether or not the subject vehicle itself is a reckless vehicle. The reckless vehicle display section288A accordingly displays the display mode for an icon representing the subject vehicle so that the subject vehicle is identified as a reckless vehicle. The subject vehicle driver can be aware of how the subject vehicle is identified from a nearby vehicle. The subject vehicle driver can develop an awareness of safe driving.

Chronological data about a nearby vehicle such as changes in the orientation angle speed or the orientation may be used by the reckless-vehicle determination section286to determine whether or not the nearby vehicle (or a target vehicle) is driven in a zigzag. Zigzag driving can be determined when the orientation angle speed (or the orientation angle) oscillates over a specified width in a different direction within a specified time period. The shape of a road the target vehicle travels may be acquired from map data. In such a case, zigzag driving may be determined based on whether or not the target vehicle appropriately varies the orientation angle speed according to the road shape. In this modification, the reckless vehicle display section288A may display the target vehicle driven in zigzag using a display mode that differs from the mode for normal vehicles and the mode for the other reckless vehicles.

According to the embodiment, map data is stored in the memory26. However, the configuration is not limited thereto. Necessary map data may be acquired by accessing an external server (unshown) if the portable terminal2can use a mobile telephone line. The program4may be stored in an external server.