Patent Publication Number: US-2021185497-A1

Title: Control device and vehicle

Description:
TECHNICAL FIELD 
     The present disclosure relates to a control apparatus and a vehicle. 
     BACKGROUND ART 
     A vehicle-to-vehicle communication system has been known, in which communication is performed among vehicles by relaying data among a plurality of vehicles, for example. 
     CITATION LIST 
     Patent Literature 
     PTL 1 
     Japanese Patent Application Laid-Open No. 2004-80383 
     SUMMARY OF INVENTION 
     Technical Problem 
     Meanwhile, in places where a plurality of roads cross each other or run in parallel, there may be many vehicles that relay data. Consequently, data may be congested and cannot be transmitted and received smoothly when communication is performed between vehicles, and thus, a communication speed may be reduced. 
     An object of the present disclosure is to provide a control apparatus and a vehicle capable of suppressing reduction in a communication speed. 
     Solution to Problem 
     To achieve the above-mentioned object, a control apparatus according to the present disclosure includes: 
     a determination section that determines whether a surrounding vehicle positioned around a first vehicle travels on a same travel road as the first vehicle; 
     a relay vehicle selection section that selects, among a plurality of the surrounding vehicles, a vehicle which is determined by the determination section to be traveling on the same travel road as the first vehicle, as a second vehicle that relays data from the first vehicle in vehicle-to-vehicle communication in which communication between vehicles is performed; and 
     a vehicle-to-vehicle communication control execution section that executes control for vehicle-to-vehicle communication section of the first vehicle to perform vehicle-to-vehicle communication with the second vehicle 
     A vehicle according to the present disclosure includes: 
     the control apparatus. 
     Advantageous Effects of Invention 
     The present disclosure can suppress reduction in a communication speed. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         FIG. 1  is a block diagram schematically illustrating a configuration of a vehicle control apparatus according to an embodiment of the present disclosure; 
         FIG. 2  schematically illustrates a first vehicle and surrounding vehicles positioned around the first vehicle in a grade separated junction of freeway and general road; and 
         FIG. 3  is a flowchart illustrating an exemplary processing operation of the vehicle control apparatus according to the embodiment. 
     
    
    
     DESCRIPTION OF EMBODIMENTS 
     Hereinafter, an embodiment of the present disclosure will be described in detail with reference to the drawings.  FIG. 1  is a block diagram schematically illustrating a configuration of vehicle control apparatus  1  according to the embodiment of the present disclosure. Vehicle control apparatus  1  includes satellite positioning section  2 , vehicle-to-vehicle communication section  3 , and control section  5 . Vehicle control apparatus  1  is installed in each vehicle. Hereinafter, vehicle control apparatus  1  will be described as being installed in the first vehicle. 
     Satellite positioning section  2  measures a position (longitude, latitude, and altitude) of the vehicle. For example, a publicly known Global Positioning System (GPS) is used for satellite positioning section  2 . Note that, information on the vehicle position to be measured by satellite positioning section  2  includes information on a vehicle orientation. 
     Vehicle-to-vehicle communication section  3  is a communication device that performs transmission and reception between vehicles, using a radio wave of a predetermined frequency band, and vehicle-to-vehicle communication section  3  exchanges various kinds of information on vehicles between vehicles. The various kinds of information on vehicles herein includes information on the vehicle position (longitude, latitude, and altitude) measured by satellite positioning section  2  and measurement accuracy of the vehicle position. 
     Control section  5  is configured of a microcomputer including a Central Processing Unit (CPU), Read Only Memory (ROM), Random Access Memory (RAM), an input interface, and an output interface. The CPU reads out programs corresponding to processing from ROM, loads the programs into RAM, and centrally controls operations of respective blocks, cooperating with the loaded programs. In the present embodiment, control section  5  has functions as acquisition section  51 , traveling trajectory generation section  52 , distance calculation section  53 , orientation difference calculation section  54 , determination section  55 , relay vehicle selection section  56 , and vehicle-to-vehicle communication control execution section  57 . Note that, these functions may be included in an Electric Control Unit (ECU), which is a device that controls respective systems of the vehicle by using an electronic circuit. Meanwhile, any part or all of these functions may be provided separately from the ECU. 
     Acquisition section  51  acquires position information on the first vehicle from satellite positioning section  2 . In addition, acquisition section  51  also acquires position information on a surrounding vehicle transmitted from one or more surrounding vehicles positioned around the first vehicle via vehicle-to-vehicle communication section  3 . 
     Incidentally, a method has been known, which relays communication data by vehicle-to-vehicle communication section  3  installed in a surrounding vehicle while using a surrounding vehicle positioned around the first vehicle for relaying (referred to as “hopping”). 
     In one example, an approach signal notifying an approach of an emergency vehicle is transmitted from the first vehicle to a preceding surrounding vehicle. The preceding surrounding vehicle that has received the approach signal further transmits the approach signal to a vehicle traveling ahead of the preceding surrounding vehicle. 
     Further, for example, an approach signal notifying an approach of a place where a traffic accident has occurred is transmitted from the first vehicle to a following surrounding vehicle. The following surrounding vehicle that has received the approach signal further transmits the approach signal to a vehicle traveling behind of the following surrounding vehicle. 
     However, when there are many surrounding vehicles around the first vehicle, for example, in places where a plurality of roads cross each other, data transmitted from the first vehicle may be congested and cannot be transmitted and received smoothly when vehicle-to-vehicle communication is performed, which may reduce a communication speed. The reduction in a communication speed may cause the first vehicle to fail in transmitting the approach signal to the surrounding vehicle. 
     In order to surely transmit the approach signal from the first vehicle to the surrounding vehicle, it is necessary to select a second vehicle that relays the data from the first vehicle in vehicle-to-vehicle communication and to relay communication data, using the selected second vehicle. 
     In the following description, one of the first vehicle and the surrounding vehicle is assumed to as a preceding vehicle and the other one of the first vehicle and the surrounding vehicle is assumed to be a following vehicle. 
     In the present embodiment, traveling trajectory generation section  52  generates a traveling trajectory of the preceding vehicle on a virtual plane based on a time series of position information on the preceding vehicle acquired by acquisition section  51 . 
     Distance calculation section  53  calculates a distance between the traveling trajectory of the preceding vehicle generated by traveling trajectory generation section  52  and a present position information on the following vehicle acquired by acquisition section  51 . Specifically, distance calculation section  53  calculates the length of a perpendicular line drawn from the present position information on the following vehicle to the traveling trajectory of the preceding vehicle. 
     Orientation difference calculation section  54  calculates an orientation difference between an orientation of the traveling trajectory at an intersection of the traveling trajectory of the preceding vehicle and the perpendicular line, and a present orientation (traveling direction) of the following vehicle. Note that, the position information on a vehicle to be measured by satellite positioning section  2  includes information on a vehicle orientation. 
     Incidentally, when the measurement accuracy of the positions of surrounding vehicles is low due to various factors, an error between the measured position information on a surrounding vehicle and an actual position information on the surrounding vehicle becomes large, and thus, the traveling trajectory to be generated by traveling trajectory generation section  52  significantly deviates from an actual traveling trajectory. Consequently, the distance calculated by distance calculation section  53  may be significantly different from an actual distance. Further, the orientation difference calculated by orientation difference calculation section  54  may also significantly deviate from an actual orientation difference. As a result, determination section  55  may erroneously determine whether the surrounding vehicle travels on the same travel road as the first vehicle. Note that, in the present embodiment, a criterion for determining that the travel roads are the same is whether at least a part of the traveling trajectories generated by illustrating passing points of vehicles on the virtual plane overlaps, not whether the roads in a map data are the same. 
     Then, in the present embodiment, when the measurement accuracy of the positions of surrounding vehicles is not less than a predetermined value, traveling trajectory generation section  52  generates the traveling trajectory, distance calculation section  53  calculates the distance, and orientation difference calculation section  54  calculates the orientation difference. Determination section  55  determines whether the surrounding vehicle travels on the same travel road as the first vehicle, based on the calculated distance and the calculated orientation difference. 
     On the other hand, when the measurement accuracy of the positions of surrounding vehicles is less than a predetermined value, traveling trajectory generation section  52  does not generate the traveling trajectory, distance calculation section  53  does not calculate the distance, and orientation difference calculation section  54  does not calculate the orientation difference. Accordingly, determination section  55  does not determine whether the surrounding vehicle travels on the same travel road as the first vehicle. 
     Determination section  55  determines that the following vehicle travels on the same travel road as the preceding vehicle in a case where the distance calculated by distance calculation section  53  is not greater than a predetermined distance, and the orientation difference calculated by orientation difference calculation section  54  is not greater than a predetermined angle either. In the following description, “traveling on the same travel road” means that the following vehicle travels on the same travel road as the preceding vehicle travels, and that the preceding vehicle has traveled on the same travel road as the following vehicle has traveled 
     Relay vehicle selection section  56 , among the surrounding vehicles, selects a vehicle (the other one of the preceding vehicle and the following vehicle) determined by determination section  55  to be traveling the same travel road as the first vehicle (one of the preceding vehicle and the following vehicle) as the second vehicle that relays the data from the first vehicle in inter-vehicle communication. 
     Vehicle-to-vehicle communication control execution section  57  executes control for vehicle-to-vehicle communication section  3  to perform vehicle-to-vehicle communication with the second vehicle. Thus, for example, the second vehicle is notified that it has been selected as a vehicle that relays the data from the first vehicle. 
     Next, a concrete example of vehicle control apparatus  1  will be described with reference to  FIG. 2 .  FIG. 2  schematically illustrates a first vehicle and a plurality of surrounding vehicles in a grade separated junction of freeway and general road. Note that, a traveling trajectory will be generated for each vehicle; however, for simplicity of description, traveling trajectory T 1  of first vehicle V 14 , surrounding vehicles V 11 , V 12 , V 13 , V 15 , V 16 , and V 17  is assumed to be the same as each other. Traveling trajectory T 2  of surrounding vehicle V 21  is assumed to be different from traveling trajectory T 1 . Traveling trajectory T 3  of surrounding vehicles V 31 , V 32 , V 33 , V 34 , and V 35  is assumed to be the same as each other and different from traveling trajectory T 1 . Further, traveling trajectory T 4  of surrounding vehicles V 41 , V 42 , V 43 , V 44 , and V 45  is assumed to be the same as each other and different from traveling trajectory T 1 . 
     In the following description, a traveling direction of a vehicle may be referred to as “ahead” or “forward direction”, and surrounding vehicles V 11 , V 12 , and V 13  that precede first vehicle V 14  may be each referred to as a “preceding vehicle”. Here, first vehicle V 14  will be described as an emergency vehicle. 
     [Surrounding Vehicle V 11 ] 
     Acquisition section  51  of first vehicle V 14  acquires position information on first vehicle V 14  measured by satellite positioning section  2 . Acquisition section  51  of first vehicle V 14  also acquires position information on surrounding vehicle V 11  received from vehicle-to-vehicle communication section  3 . Note that, measurement information on the position of surrounding vehicle V 11  is assumed to be not less than a specified value. 
     When measurement accuracy of the position of surrounding vehicle V 11  is not less than the specified value, control section  5  of first vehicle V 14  executes control of second vehicle selection processing. 
     Traveling trajectory generation section  52  of first vehicle V 14  generates traveling trajectory T 1  (see  FIG. 2 ) of surrounding vehicle V 11  on a virtual plane based on a time series of position information on surrounding vehicle V 11 . 
     Distance calculation section  53  of first vehicle V 14  calculates a distance between traveling trajectory T 1  of surrounding vehicle V 11  and the present position information on first vehicle V 14 . 
     Orientation difference calculation section  54  of first vehicle V 14  calculates an orientation difference between an orientation of traveling trajectory T 1  of surrounding vehicle V 11  and the present orientation of first vehicle V 14 . 
     Determination section  55  of first vehicle V 14  determines that surrounding vehicle V 11  travels on the same travel road as first vehicle V 14  in a case where the distance calculated by distance calculation section  53  is not greater than the predetermined distance, and the orientation difference calculated by orientation difference calculation section  54  is not greater than the predetermined angle either. 
     When surrounding vehicle V 11  is determined to be traveling on the same travel road as first vehicle V 14  by determination section  55 , relay vehicle selection section  56  of first vehicle V 14  selects surrounding vehicle V 11  as the second vehicle that relays the data from first vehicle V 14  in inter-vehicle communication. 
     [Surrounding Vehicle V 12 ] 
     Here, measurement information on the position of surrounding vehicle V 12  is assumed to be not less than a specified value. Traveling trajectory generation section  52  of first vehicle V 14  generates traveling trajectory T 1  (see  FIG. 2 ) of surrounding vehicle V 12  on a virtual plane based on a time series of position information on surrounding vehicle V 12 . Distance calculation section  53  of first vehicle V 14  calculates a distance between traveling trajectory T 1  of surrounding vehicle V 12  and the present position information on first vehicle V 14 . Orientation difference calculation section  54  of first vehicle V 14  calculates an orientation difference between an orientation of traveling trajectory T 1  of surrounding vehicle V 12  and the present orientation of first vehicle V 14 . 
     Determination section  55  of first vehicle V 14  determines that surrounding vehicle V 12  travels on the same travel road as first vehicle V 14  in a case where the distance calculated by distance calculation section  53  is not greater than the predetermined distance, and the orientation difference calculated by orientation difference calculation section  54  is not greater than the predetermined angle either. When surrounding vehicle V 12  is determined to be traveling on the same travel road as first vehicle V 14  by determination section  55 , relay vehicle selection section  56  of first vehicle V 14  selects surrounding vehicle V 12  as the second vehicle that relays the data from first vehicle V 14  in inter-vehicle communication. 
     [Surrounding Vehicle V 13 ] 
     Here, measurement information on the position of surrounding vehicle V 13  is assumed to be less than a specified value. When measurement accuracy of the position of surrounding vehicle V 13  is less than a specified value, control section  5  first vehicle V 14  does not execute control of second vehicle selection processing. Thus, surrounding vehicle V 13  is not selected as the second vehicle. 
     [Surrounding Vehicles V 15 , V 16 , and V 17 ] 
     In a case where it is assumed that first vehicle V 14  is an emergency vehicle, and an approach signal is notified to a preceding vehicle of first vehicle V 14 , surrounding vehicles V 15 , V 16 , and V 17 , that is, following vehicles of first vehicle V 14 , are not selected as second vehicles. 
     [Surrounding Vehicle V 21 ] 
     For surrounding vehicle V 21 , processing similar to the second vehicle selection processing in surrounding vehicle V 11  is executed. In this case, the travel road of surrounding vehicle V 21  (traveling trajectory T 2 ) is different from the travel road of first vehicle V 14  (traveling trajectory T 1 ), so that surrounding vehicle V 21  is not selected as the second vehicle. 
     [Surrounding Vehicles V 31  and the Like] 
     For surrounding vehicles V 31 , V 32 , V 33 , V 34 , and V 35 , processing similar to second vehicle selection processing in surrounding vehicle V 11  is executed. In this case, the travel road of surrounding vehicles V 31 , V 32 , V 33 , V 34 , and V 35  (traveling trajectory T 3 ) is different from the travel road of first vehicle V 14  (traveling trajectory T 1 ), so that surrounding vehicles V 31 , V 32 , V 33 , V 34 , and V 35  are not selected as the second vehicle. 
     [Surrounding Vehicles V 41  and the Like] 
     For surrounding vehicles V 41 , V 42 , V 43 , V 44 , and V 45 , processing similar to second vehicle selection processing in surrounding vehicle V 11  is executed. In this case, the travel road of surrounding vehicles V 41 , V 42 , V 43 , V 44 , and V 45  (traveling trajectory T 4 ) is different from the travel road of first vehicle V 14  (traveling trajectory T 1 ), so that surrounding vehicles V 41 , V 42 , V 43 , V 44 , and V 45  are not selected as the second vehicle. 
     Thus, in a case where first vehicle V 14  is assumed to be an emergency vehicle, the second vehicle that relays the approach signal notifying an approach of the emergency vehicle is limited to surrounding vehicles V 11  and V 12 . For example, first vehicle V 14  notifies surrounding vehicles V 11  and V 12  of being selected as the second vehicle. When receiving data from first vehicle V 14 , surrounding vehicles V 11  and V 12  determine whether to relay the received data, in accordance with the notification. 
     Next, a description will be given of a processing operation of vehicle control apparatus  1  according to the embodiment with reference to  FIG. 3 .  FIG. 3  is a flowchart illustrating an exemplary processing operation of vehicle control apparatus  1  according to the embodiment. The flow is appropriately started during traveling of a vehicle. 
     First, in step S 100 , acquisition section  51  acquires position information on a surrounding vehicle positioned around the first vehicle. 
     Then, in step S 110 , determination section  55  determines whether the measurement accuracy of the position of the surrounding vehicle is not less than the specified value. When the measurement accuracy of the position of the surrounding vehicle is not less than the specified value (step S 110 : YES), the processing proceeds to step S 120 . When the measurement accuracy of the position of the surrounding vehicle is less than the specified value (step S 110 : NO), the processing ends. 
     In step S 120 , traveling trajectory generation section  52  generates a traveling trajectory on the surrounding vehicle based on the position information on the surrounding vehicle. 
     Then, in step S 130 , distance calculation section  53  calculates a distance between the traveling trajectory of the surrounding vehicle and the present position information on the first vehicle. 
     Then, in step S 140 , orientation difference calculation section  54  calculates an orientation difference between an orientation of the traveling trajectory of the surrounding vehicle and the present orientation of the first vehicle. 
     Then, in step S 150 , determination section  55  determines whether the distance calculated by distance calculation section  53  is not greater than the predetermined distance. When the distance is not greater than the predetermined distance (step S 150 : YES), the processing proceeds to step S 160 . When the distance is greater than the predetermined distance (step S 150 : NO), the processing ends. 
     In step S 160 , determination section  55  determines whether the orientation difference calculated by orientation difference calculation section  54  is not greater than the predetermined angle. When the orientation difference is not greater than the predetermined angle (step S 160 : YES), the processing proceeds to step S 170 . When the orientation difference is greater than the predetermined angle (step S 160 : NO), the processing ends. 
     In step S 170 , relay vehicle selection section  56  selects the surrounding vehicle as the second vehicle that relays the data from the first vehicle in inter-vehicle communication. 
     In step S 180 , vehicle-to-vehicle communication control execution section  57  executes control for vehicle-to-vehicle communication section  3  to perform vehicle-to-vehicle communication with the second vehicle. 
     Vehicle control apparatus  1  according to the above embodiment includes: determination section  55  that determines whether a surrounding vehicle positioned around a first vehicle travels on a same travel road as the first vehicle; and relay vehicle selection section  56  that selects, among a plurality of the surrounding vehicles, a vehicle which is determined by determination section  55  to be traveling on the same travel road as the first vehicle, as a second vehicle that relays data from the first vehicle in vehicle-to-vehicle communication in which communication between vehicles is performed. Thus, even when there are many surrounding vehicles around the first vehicle, it is possible to specify a surrounding vehicle as the second vehicle. This enables smoothly transmitting and receiving the data from the first vehicle without congestion in vehicle-to-vehicle communication, and thus, the reduction in a communication speed can be suppressed. 
     In addition, determination section  55  determines whether the surrounding vehicle travels on the same travel road as the first vehicle based on the distance between the traveling trajectory of the surrounding vehicle and the present position information on the first vehicle and the orientation difference between the orientation of the traveling trajectory of the surrounding vehicle and the present orientation of the first vehicle. This enables determining whether the surrounding vehicle travels on the same travel road as the first vehicle without using map data. 
     Further, control section  5  does not execute control of second vehicle selection processing when the measurement accuracy of the position of the surrounding vehicle is less than the specified value. This reduces an error in selecting the second vehicle, and thereby, the data from the first vehicle can be smoothly relayed. 
     Besides, determination section  55  determines whether the surrounding vehicle travels on the same travel road as the first vehicle based on the orientation difference between the orientation of the traveling trajectory of the preceding vehicle and the present orientation of the following vehicle. This also reduces an error in selecting the second vehicle, and thereby, the data from the first vehicle can be smoothly relayed. 
     In the above embodiment, relay vehicle selection section  56  may select, for example, surrounding vehicle V 21  that travels on traveling trajectory T 2  illustrated in  FIG. 2 , as the second vehicle. In this case, relay vehicle selection section  56  selects, as the second vehicle, surrounding vehicle V 11  and/or the like that travels on the lane as traveling trajectory T 1  on which first vehicle V 14  travels in preference to surrounding vehicle V 21  that travels on the adjacent lane as traveling trajectory T 2 . Thus, for example, when the number of surrounding vehicles that travel on a lane as the second vehicle is small, the surrounding vehicle that travels on a lane adjacent to the lane is selected as the second vehicle, which enables smoothly transmitting and receiving the data from the first vehicle in vehicle-to-vehicle communication. 
     In the above embodiment, satellite positioning section  2  is used as a positioning device that measures the position of the vehicle; however, the positioning device is not limited to satellite positioning section  2 , may be a device that performs measuring from data obtained by a vehicle speed sensor, a yaw rate sensor, or a steering angle sensor, using what is called autonomous navigation system, and/or may be a device that uses a beacon and/or the like. 
     In the above embodiment, selection of the second vehicle that relays the data from the first vehicle is performed for each vehicle; however, the selection may be performed for each vehicle group of platooning vehicles. 
     The embodiments described above are merely examples of specific implementation of the present disclosure, and the technical scope of the present disclosure should not be restrictively interpreted by these embodiments. That is, the present disclosure may be implemented in various forms without departing from the spirit thereof or the major features thereof. 
     This application is based on Japanese Patent Application No. 2018-163362, filed on Aug. 31, 2018, the contents of which are incorporated herein by reference. 
     INDUSTRIAL APPLICABILITY 
     The present disclosure is suitably used for a vehicle which includes a control apparatus that is required to suppress reduction in a communication speed. 
     REFERENCE SIGNS LIST 
     
         
           1  Vehicle control apparatus 
           2  Satellite positioning section 
           3  Vehicle-to-vehicle communication section 
           5  Control section 
           51  Acquisition section 
           52  Traveling trajectory generation section 
           53  Distance calculation section 
           54  Orientation difference calculation section 
           55  Determination section 
           56  Relay vehicle selection section 
           57  Vehicle-to-vehicle communication control execution section