JP2007286994A - Driving support system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To detect the position and speed of vehicles by an inexpensive system configuration without the influence of obstacles irrespective of the number of traffic lanes and the travel direction of vehicles. <P>SOLUTION: A radio station 10 for radiating a radio signal in all directions to communicate with particular moving bodies within a communication area is installed near the center of a road intersection. Moving bodies 20 to 24 each have a GPS device for receiving data from GPS satellites to detect the position and speed of the moving bodies, a storage device for storing the detected position and speed when necessary, and a radio device for establishing communication with the radio station. The radio station, when detecting some moving bodies by the response of the moving bodies to a transmitted beacon, transmits the position and speed of the moving bodies received from the moving bodies to the other moving bodies receiving this service within the communication area. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a driving support system using wireless communication or the like, and in particular, includes a moving body that moves at a relatively low speed, such as a pedestrian or a bicycle, on a road, and a moving body that moves at a relatively high speed, such as an automobile or a motorcycle. The present invention relates to a collision avoidance technique between bodies.

  As this type of conventional technology, in Patent Document 1, a roadside device that detects the position and speed of an automobile entering an intersection is installed at each of the intersections of the intersection, and when an automobile entering the intersection is detected, By transmitting the detected position and speed of the vehicle to the roadside device installed at the crossroads and further informing this to other vehicles, the vehicles entering the intersection acquire each other's position and speed. "An encounter head collision prevention device-a recording medium" is described.

  In Patent Document 2, a roadside wireless device is installed near a curve with poor visibility, a vehicle entering the curve from both directions is detected, and the vehicle is informed of the road conditions ahead of the vehicle with poor visibility. The driving support system "is described.

  Further, in Patent Document 3, tag information reading means provided on a road including a sidewalk or a roadway reads an information tag installed in an automobile and an information tag carried by a pedestrian, and the read tag information is roadside road judgment. By calculating the moving speed and moving direction from the position change of the moving body, the collision risk between the low-speed and high-speed moving bodies is predicted, and if the danger is predicted, the moving body is notified of the danger. An information tag, a roadside wireless transmission / reception device, an in-vehicle wireless transmission / reception device, and a traffic safety support device ”are described.

Japanese Patent Laid-Open No. 2001-143197 (pages 4 to 6, FIG. 1) JP 2004-280382 A (page 3, FIG. 1) Japanese Unexamined Patent Publication No. 2003-346297 (pages 4-7, FIG. 3)

  However, in any of the above-described conventional techniques, when there are a plurality of one-side traveling lanes, there is a first problem that it is impossible to detect from which lane the vehicle entering the intersection enters.

  Further, in any of the above-described prior arts, there is a second problem that it is impossible to detect whether the vehicle that has entered the intersection goes straight, or whether it travels in the right turn or left turn.

  Furthermore, in the technique described in Patent Document 1, the position of the vehicle entering the intersection (the lane cannot be identified) and the speed are communicated with the vehicle using a vehicle sensor provided in the roadside device. However, it requires a special sensor and requires a large amount of money to construct a collision avoidance system between moving objects. Also, once the system is built on the road, in addition to the relocation cost, it is necessary to select an installation location that is not affected by obstacles, etc., and it may be very difficult to handle maintenance. Furthermore, it is assumed that it is difficult to detect the vehicle entering the intersection due to the directivity of the vehicle sensor and the influence of the roadside parked vehicle and other traveling vehicles.

  In the technique described in Patent Document 2, a roadside radio and a radio wave detection device must be provided, and the system construction cost is high. Due to the directivity of the radio wave direction detection device and the influence of roadside parking vehicles and other traveling vehicles, It is assumed that it is difficult to detect a vehicle entering the intersection.

  In the technique described in Patent Document 3, since the position and speed are detected by passing through the communication area of the tag information reading unit, the installation interval of the tag information reading unit is measured in advance, which is complicated by the system construction. There are many problems such as needing to maintain parameters related to the installation interval and the installation interval for detecting the speed during operation.

  Therefore, the first object of the present invention is to determine from which lane the vehicle entering the intersection enters, even in the case where there are a plurality of one-side lanes, and in which direction (straight, right turn) The purpose of the present invention is to provide a driving support system that can detect whether the vehicle is going to turn left.

  A second object of the present invention is to provide a driving support system that enables an inexpensive system construction and can easily cope with a change in installation after the system construction.

  A third object of the present invention is to provide a driving support system capable of detecting a vehicle and detecting the position and speed without being affected by obstacles such as other parked vehicles, traveling vehicles, and buildings. is there.

  The first driving support system according to the present invention includes a radio station capable of communicating with a specific mobile body in a communication area by radiating a radio signal in all directions near the center of a road intersection. A mobile unit that receives data from GPS satellites to detect the position and speed of the mobile unit, a storage unit that stores the detected position and speed as needed, and a radio unit that communicates with a radio station And when the mobile body is found by the reaction of the mobile body to the beacon transmitted by the wireless station, the mobile terminal determines whether the mobile body is allowed to participate in the network based on the identification code received from the mobile body, and receives the mobile body from the mobile body. The position and speed of the mobile body thus transmitted are transmitted to another mobile body to be serviced in the communication area.

  The second driving support system of the present invention communicates with a specific mobile body in a communication area by radiating radio signals in all directions to each road in the direction in which the mobile body enters as viewed from the vicinity of the center of the intersection. A sub-radio station that is capable of transmitting, a main radio station as a coordinator that organizes the communication network of the sub-radio station near the center of the intersection, and the mobile unit receives data from a GPS satellite A GPS device that detects the position and speed of the mobile body, a storage device that stores the detected position and speed as needed, a wireless device that communicates with the wireless station, and a beacon transmitted by the sub wireless station. When the mobile body is found by the reaction of the mobile body to the mobile station, the mobile terminal decides whether to allow the mobile body to participate in the network based on the identification code received from the mobile body. Upon receipt of the search request signal, the mobile station receives the position and speed of the mobile body received from the mobile body, returns its own address number to the main radio station, and sends the radio station search request signal to the sub radio station at a predetermined cycle. Transmitting and receiving a reply from the sub radio station transfers the position and speed of the moving body to other sub radio stations in the area.

  In addition, when the mobile unit is located in a plurality of communication areas of the sub radio station, the main radio station performs mobile unit management in the sub radio station that first permits participation in the network based on the movement prediction of the mobile unit. It may be controlled to give priority to management by a sub-radio station that is stopped and allowed to join the network later.

  In addition, when the load on the network is light as a whole, the main radio station also has the authority to permit network participation from the detection of the moving object. On the other hand, if the traffic volume of the moving object in the network increases and the load becomes higher, The authority may be temporarily lost.

  According to the present invention, a specific movement within a communication area can be achieved by radiating a radio signal in all directions to each of the roads in the vicinity of the intersection of the road and in the direction in which the mobile body enters as viewed from the vicinity of the center of the intersection. Even if there are multiple lanes, wireless stations that can communicate with the body are arranged and the mobile body collects its own position and speed obtained by GPS by wireless communication with the mobile body. In addition, it is possible to detect the vehicle and detect the position and speed without being affected by obstacles, even in places where visibility is poor or when the moving body travels from any direction to any direction. Can do.

  Furthermore, if a radio station is installed, it is only necessary to use the GPS function of the mobile body. Therefore, it is possible to construct an inexpensive system and easily cope with a change in installation after the system construction. .

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

[Description of configuration]
FIG. 1 shows a scene where the first embodiment of the driving support system of the present invention is applied. In FIG. 1, road No. 1 with two lanes on one side and road No. 2 with one lane on one side are orthogonal to the east, west, south, and north, and a radio station 10 is provided near the center of the intersection. The radio station 10 may be wirelessly communicable, whether it is a road-embedded type or a road-installed type. The radio station 10 can communicate with specific radio means in the communication area 10A by radiating radio signals in all directions, but it is installed at the center of the intersection. It is possible to communicate with a moving body on any route.

  Further, the radio station 10 incorporates an identification table in which identification codes of mobile objects that can receive this service are registered. There are four moving bodies 20-24 on the road. The mobile bodies 20 to 24 can communicate with the radio station 10 in the communication area 10A. If a mobile body exists in the communication area 10A, a radio network is formed by permission of the radio station 10.

  FIG. 2 is a block diagram showing the configuration of each of the moving bodies 20-24. Since all of the moving bodies 20 to 24 adopt the same configuration, the moving body will be described below by taking the moving body 20 as an example. The mobile unit 20 includes a radio unit 20a that communicates with the radio station 10, a GPS unit 20b that detects the position and speed of the mobile unit 20 by receiving data from a GPS satellite (not shown), and a GPS unit 20b. Is provided with a storage device 20c for storing the position and speed detected at any time.

  Note that detection of the position and speed of the moving body by the GPS device 20b is a well-known technique and will be omitted in the description of the present invention. The position of the moving body is detected with an accuracy capable of identifying the traveling lane. In addition, the moving body includes an automobile, a motorcycle, an electric vehicle corresponding to these, and a pedestrian. In the case of a pedestrian, a portable device of a module in which the wireless device 20, the GPS device 20b, and the storage device 20c are set as one set is carried around.

[Description of operation]
Next, the operation of this driving support system will be described with reference to the operation flowchart of FIG. As shown in FIG. 1, the mobile bodies 20 and 21 exist in the communication area 10A, and the mobile bodies 22 and 24 are about to enter the communication area 10A. There is still a distance for the moving body 23 to enter the communication area 10A. The radio station 10 detects the moving object in the communication area 10A, for example, by transmitting a beacon and receiving a return from the moving object.

  First, when the radio station 10 transmits a beacon, the mobile units 20 and 21 transmit their identification codes by receiving the beacon. The radio station 10 finds the moving object by reacting to the beacon (step S1 in FIG. 3). Then, the radio station 10 searches whether the received identification code is registered in the identification table in the apparatus, and permits only the moving body of the matching identification code to participate in the network (step S2 in FIG. 3). Here, it is assumed that participation of the moving bodies 20 and 21 is permitted. In this way, it is possible to control the formation of a wireless network or the addition of a new node to the wireless network by determining whether or not to participate in the network based on the identification of the moving body.

  The mobile bodies 20 and 21 read their current position and speed detected by the GPS device 20b and stored in the storage device 20c, and transmit them to the radio station 10 (step S3 in FIG. 3). When receiving data from a plurality of (two in this example) mobile units, the radio station 10 collects data that avoids data collision at the time of reception by providing reception timing for each mobile unit accommodated in the wireless network. Is possible. In this way, the radio station 10 collects the position and speed from the mobile body that has joined the radio network.

  Upon receiving the position and speed from the mobile units 20 and 21, the radio station 10 transfers the position and speed to the other mobile units 21 and 20 that are the target of this service (step S4 in FIG. 3). The data transmission timing at this time is different from the transmission timing in the same manner as in step S3. In the above steps S3 and S4, since the reception timing and transmission timing are set in correspondence with the mobile object, for example, when data relating to its own position and speed is transmitted to the radio station 10, until another mobile object receives it. Corrected in consideration of the phase difference between the two, it is sent out as its own position and velocity.

  In the moving body 20, the position and speed information of the received moving body 21 is displayed on the map in the car navigation system to inform the driver of the situation of the right turn direction of the intersection with poor visibility. Can do. Similarly, in the moving body 21, the position information of the moving body 20 can be notified to the driver.

  Now, when the mobile 20 turns left from the No. 2 road to the No. 1 road ascending lane 1a as time passes, the no. 22 mobile is located in the No. 1 road ascending lane 1a and enters the communication area 10A from outside the communication area. Suppose you have entered. The mobile unit 22 sends its position and speed to the radio station 10. Then, the mobile body 20 receives the position and speed information of the mobile body 22 via the radio station 10 (step S4 in FIG. 3), and moves the mobile body 22 coming up from the downward direction of the traveling lane 1a scheduled to turn left. Detect and inform the driver through the display screen. Note that the means for notifying the driver of the road condition with poor visibility may be a sound notification, or may be further cautioned by adding a sound to the visual notification.

  When the mobile body that has entered the communication area 10A goes out of the communication area 10A (step S5 in FIG. 3), the radio station 10 disconnects communication with the mobile body (step S6 in FIG. 3). As a result, it is possible to reduce the load on the wireless network that occurs when a large number of moving bodies move on the road.

  In the present embodiment, the design of the wireless network is modified, four wireless stations 11 to 14 are added to the wireless station 10 configured in the first embodiment, and mutual communication between the wireless station 10 and the wireless stations 11 to 14 is performed. The wireless network is expanded.

  FIG. 4 shows a scene where the second embodiment of the driving support system of the present invention is applied. Here, a radio network composed of radio stations 10 to 14 is formed. In this radio network, radio stations 10 arranged in the vicinity of the center of the intersection and radio roads in four directions entering from the vicinity of the center of the intersection are wirelessly connected. Stations 11 to 14 are arranged. The radio station 10 has a function as a coordinator that organizes communication networks of the other radio stations 11 to 14, and has a communication coverage (communication area) capable of communicating with all the radio stations 11 to 14.

  In the case of the radio station 10, this communication coverage state is shown in the communication area 10A, and the radio stations 11 to 14 are arranged in the communication area 10A. The radio stations 11 to 14 arranged around the radio station 10 also have communication areas 11A to 14A, respectively, are arranged at a distance including the radio station 10 in each communication area, and mutually communicate with the radio stations 10. Can communicate.

  The wireless network detects a moving body entering the wireless network from outside (outside the outer periphery of the communication areas 10A to 14A), receives position and speed information of the moving body transmitted from the moving body, and wirelessly The station 10 relays and communicates with other radio stations by the radio device 20a. Note that the radio station 10 periodically communicates with the radio stations 11 to 14, and allows the radio stations 11 to 14 to manage the mobile objects existing in the respective communication areas 11A to 14A. Control load balancing. That is, information on the position and speed of the moving body detected by the wireless stations 11 to 14 is relayed to other wireless stations, and the state of the vicinity of the intersection is notified from the wireless station to the other moving bodies.

  The radio stations 11 to 14 transmit the detected mobile object information to the radio station 10 and a function of detecting a mobile object entering the communication area 11A to 14A of the own, a function of determining whether or not the mobile object is allowed to enter the network. A function, a function of transmitting mobile body information detected by another radio station received from the radio station 10 to a mobile body within its own communication area, and a function of removing a mobile body out of communication range from the network . That is, the radio stations 11 to 14 have a function of the radio station 10 of the first embodiment except for step S4 in FIG. 3 and a function of transmitting the detected mobile information to the radio station 10.

  First, a procedure for establishing a wireless network will be described. The radio station 10 transmits a radio station search request signal at a predetermined cycle in order to search for radio stations existing around it. This radio station search request signal is composed of a format code defined in common by the radio stations 10-14. The radio station search request signal transmitted from the radio station 10 is received by the radio stations 11 to 14 arranged around the radio station 10. Each of the radio stations 11 to 14 sends a radio station search response signal to the radio station 10 at a random timing with its own address number as a response to the radio station search request signal. Since the random timing generation method is well known, the description thereof is omitted. With this procedure, a one-to-n wireless network is formed between the wireless station 10 and the wireless stations 11-14.

  The procedure for detecting the moving body in each of the radio stations 11 to 14 and the procedure for collecting the position / speed information of the moving body are the same as those in the first embodiment. Each of the radio stations 11 to 14 divides the position / velocity information of the moving body collected at a predetermined cycle into one data or a plurality of data and transmits the data to the radio station 10.

  The radio station 10 that has received the position / velocity information of the mobile unit from the radio stations 11 to 14 transfers it to the mobile unit within its own communication area. The mobile body that has received the position / velocity information of the (other) mobile body acquires the status of the other mobile body that enters toward the intersection or the mobile body that parks, and maps the mobile body information to its own map application. Thus, the mobile operator is notified of the situation of the intersection.

  In addition, when the mobile body is located in a plurality of communication areas, the wireless stations 11 to 14 covering the communication area may be allowed to participate in the network, or the wireless station 10 may function as a coordinator. The priority communication area may be selected by use, and the plurality of radio stations may be instructed to be managed by any one radio station. As a means for being managed by any one of the radio stations, based on the movement prediction of the mobile object, the mobile object management at the radio station that first permitted participation in the network is stopped, and later the network The control is performed so as to give priority to the management by the wireless station permitted to participate.

  Further, while defining the roles of the radio stations 10 to 14 as described above and operating the radio network, the management range of the mobile object is set to the radio station 10 and the radio station 11 according to the load status of the radio network. You may change dynamically between ~ 14. As an example of dynamically changing the management range of such a mobile unit, when the load on the radio network is light as a whole, the radio station 10 also has the authority to permit network participation from the detection of the mobile unit. It is assumed that the moving path of the moving body is collected in more detail.

  On the other hand, when the traffic volume of a mobile unit in a wireless network increases and the load increases, the control of whether to participate in the mobile unit is limited to only the radio stations 11 to 14, and the authority function related to whether the radio station 10 can participate in the mobile unit is temporarily It is possible to reduce the load on the radio station 10 by eliminating it. Such dynamic change monitors the traffic volume of the mobile body received by the radio station 10 from other radio stations, and dynamically changes the control when a certain traffic volume is exceeded.

  Further, information obtained by adding mobile body control information to the above two embodiments may be transmitted to the radio station. That is, when the moving body is an automobile, a motorcycle, or a moving body corresponding thereto, the intention of the driver of the moving body including speed information measured by the automobile itself, brake depression information, turn signal (winker), etc. The control information is held as needed, or the control information is held after being recognized as being incorporated into the wireless network, and the control information is transmitted to the wireless station together with the GPS data. Other mobile bodies can know more detailed states (for example, right / left turn information by a direction indicator) in addition to the status of mobile bodies in the vicinity of the intersection received via the radio station.

The figure which shows the scene where Example 1 of the driving assistance system of this invention is applied. Block diagram of the driving support system of the present invention The flowchart of Example 1 of the driving assistance system of this invention The scene where Example 2 of the driving assistance system of this invention is applied is shown.

Explanation of symbols

10-14 radio stations
10A-14A communication area
20-24 mobile
20a radio equipment
20b GPS device
20c storage device

Claims (4)

Arranging a radio station capable of communicating with a specific mobile body in a communication area by radiating radio signals in all directions near the center of a road intersection;
The mobile body communicates with the radio station by receiving a data from a GPS satellite and detecting a position and speed of the mobile body, a storage device storing the detected position and speed as needed, and the radio station. Providing a wireless device;
When the mobile body is found by the reaction of the mobile body to the beacon transmitted by the wireless station, the mobile body receives the mobile body from the mobile body by determining whether the mobile body is allowed to participate in the network based on the identification code received from the mobile body. The position and speed of this are transmitted to the other mobile body for this service which exists in the said communication area, The driving assistance system characterized by the above-mentioned. Arranging a sub-radio station capable of communicating with a specific mobile unit in the communication area by radiating radio signals in all directions on each road in the direction in which the mobile unit enters from the vicinity of the center of the intersection; ,
Arranging a main radio station as a coordinator that brings together the communication networks of the sub radio stations in the vicinity of the center of the intersection;
The mobile body communicates with the radio station by receiving a data from a GPS satellite and detecting a position and speed of the mobile body, a storage device storing the detected position and speed as needed, and the radio station. Providing a wireless device;
When the mobile body is found by the mobile body's reaction to the beacon transmitted by the sub radio station, the mobile station is allowed to participate in the network based on the identification code received from the mobile body, and the main radio station searches for the radio station. When receiving the request signal, returning the position and speed of the mobile body received from the mobile body with its own address number to the main radio station;
Sending the radio station search request signal to the sub radio station at a predetermined cycle, and when receiving the reply from the sub radio station, transferring the position and speed of the moving body to other sub radio stations in the area A driving assistance system characterized by   The main radio station, when the mobile is located in a plurality of communication areas of the sub radio station, based on the movement prediction of the mobile, the mobile in the sub radio station that first allowed to join the network 3. The driving support system according to claim 2, wherein control is stopped so as to give priority to management by a sub-radio station permitted to join the network later. When the load on the network is light as a whole, the main radio station also has the authority to permit network participation from the detection of the mobile object, while the traffic volume of the mobile object in the network increases and the load becomes high The driving support system according to claim 2 or 3, wherein the authority is temporarily lost.

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