Patent Publication Number: US-2020279481-A1

Title: Server and Vehicle Assistance System

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a server and a vehicle assistance system. 
     2. Description of the Related Art 
     Conventionally, a technique has been proposed in which safety assistance, such as avoidance of collision with an obstacle, is provided to a vehicle with information acquired from sensors provided outside the vehicle in addition to sensors installed in the vehicle. For example, JP 2018-514016 A discloses a vehicle assistance system that identifies, using communication circuitry, at least one external camera located remotely away from and within a predefined perimeter surrounding a first vehicle, acquires, using the communication circuitry, an image feed produced by the at least one external camera, determines at least one present or upcoming vehicle scenario for the first vehicle based on vehicle information extracted from an internal source of the first vehicle, and operates the first vehicle based on the image feed. 
     SUMMARY OF THE INVENTION 
     In the technique of JP 2018-514016 A, safety assistance for a vehicle is implemented by notifying the driver of the vehicle of the presence of an obstacle in an area not visually recognizable by the driver, by using the image feed from the external camera located within the perimeter of the vehicle. However, the influence of an obstacle on a road on a vehicle is not necessarily the same among vehicles, and differs among vehicles due to a difference among the vehicles in width and the like. The technique disclosed in JP 2018-514016 A cannot provide an appropriate assistance taking the presence or absence of such influence of an obstacle on each vehicle into consideration. 
     A server according to a first aspect of the present invention includes: an infrastructure linkage unit that has a function of communicating with an infrastructure sensor that generates sensing information about an obstacle point at which an obstacle exists on a road, the infrastructure linkage unit acquiring the sensing information from the infrastructure sensor, an affected vehicle identification unit that identifies a vehicle that is affected by the obstacle, among a plurality of vehicles, as an affected vehicle, a passing ability determination unit that determines whether the affected vehicle is capable of passing by the obstacle, based on a vehicle width of the affected vehicle and a passable width of the road at the obstacle point based on the sensing information, a route designing unit that designs a detour route on which the affected vehicle travels to avoid the obstacle point, when the passing ability determination unit determines the affected vehicle is not capable of passing, and a vehicle linkage unit that has a function of communicating with an in-vehicle device installed in the affected vehicle, the vehicle linkage unit transmitting information about the detour route to the in-vehicle device. 
     A vehicle assistance system according to a second aspect of the present invention includes: a server capable of communicating with a plurality of vehicles, a plurality of in-vehicle devices each installed in each of the plurality of vehicles and an infrastructure sensor that generates sensing information about an obstacle point at which an obstacle exists on a road. The server includes: an infrastructure linkage unit that has a function of communicating with the infrastructure sensor, and acquires the sensing information from the infrastructure sensor, an affected vehicle identification unit that identifies a vehicle that is affected by the obstacle, among the plurality of vehicles, as an affected vehicle, a passing ability determination unit that determines whether the affected vehicle is capable of passing by the obstacle, based on a vehicle width of the affected vehicle and a passable width of the road at the obstacle point based on the sensing information, a route designing unit that designs a detour route on which the affected vehicle travels to avoid the obstacle point, when the passing ability determination unit determines the affected vehicle is not capable of passing, and 
     a vehicle linkage unit that has a function of communicating with the plurality of in-vehicle devices, the vehicle linkage unit transmitting information about the detour route to the in-vehicle device installed in the affected vehicle among the plurality of in-vehicle devices. 
     The infrastructure sensor includes: a sensor unit that generates the sensing information upon detecting the obstacle, and an infrastructure-side server linkage unit that transmits the sensing information to the server. The in-vehicle devices each include: a vehicle-side server linkage unit that acquires the information about the detour route from the server, and a vehicle control unit that causes the affected vehicle to travel along the detour route based on the information about the detour route acquired by the vehicle-side server linkage unit. 
     According to this invention, when an obstacle exists on a road, appropriate assistance can be provided to a vehicle affected by the obstacle. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a diagram illustrating a configuration of a vehicle assistance system according to a first embodiment of the present invention; 
         FIG. 2  is a sequence diagram illustrating autonomous movement assistance control; 
         FIG. 3  is a diagram illustrating passing ability determination processing; 
         FIG. 4  is a diagram illustrating an example of a management screen; 
         FIG. 5  is a diagram illustrating another example of the management screen; and 
         FIG. 6  is a diagram illustrating a configuration of a vehicle assistance system according to a second embodiment of the present invention. 
     
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     First Embodiment 
       FIG. 1  is a diagram illustrating a configuration of a vehicle assistance system according to a first embodiment of the present invention. The vehicle assistance system  1  illustrated in  FIG. 1  includes a server  100 , an infrastructure sensor  200 , and an in-vehicle device  300 , and assists a vehicle in which the in-vehicle device  300  is installed when the vehicle autonomously moves, by autonomous driving, on a traveling route to a designated location. Hereinafter, a vehicle to be controlled by the vehicle assistance system  1 , that is, a vehicle in which the in-vehicle device  300  is installed will be referred to as “host vehicle”. 
     The server  100  is an information apparatus that manages and assists the host vehicle, and is installed in a predetermined facility such as an information center, for example. The server  100  includes functional blocks of a vehicle linkage unit  101 , a vehicle route storage unit  102 , an infrastructure linkage unit  103 , an affected route identification unit  104 , an infrastructure management unit  105 , an affected vehicle identification unit  106 , a vehicle information storage unit  107 , a passing ability determination unit  108 , a route designing unit  109 , map information  110 , and a display unit  111 . The server  100  has unillustrated hardware configurations including a central processing unit (CPU), memory, and storage (such as a hard disk drive (HDD) or a solid state drive (SSD)), and can implement the functional blocks described above by executing a predetermined program by using such hardware. 
     The infrastructure sensor  200  is installed in the vicinity of a road traveled by the host vehicle, and detects an obstacle existing in the periphery of the road, while being outside the host vehicle. Only a single infrastructure sensor  200  is illustrated in  FIG. 1 , but a plurality of infrastructure sensors  200  may be installed in the vicinity of the road. The infrastructure sensor  200  includes functional blocks of a sensor unit  201  and an infrastructure-side server linkage unit  202 . 
     The in-vehicle device  300  is installed in the host vehicle, and performs control necessary for autonomously moving the host vehicle on a traveling route to a designated location. Only one in-vehicle device  300  is illustrated in  FIG. 1 , but a plurality of vehicles each have the in-vehicle device  300 , and the in-vehicle devices  300  may form the vehicle assistance system  1  together with the server  100  and the infrastructure sensor  200 . The in-vehicle device  300  includes functional blocks of a vehicle-side server linkage unit  301 , a route management unit  302 , a vehicle-side route designing unit  303 , a vehicle-side display control unit  304 , a vehicle-side display unit  305 , map information  306 , a vehicle position determination unit  307 , and a vehicle control unit  308 . 
     Next, each functional block of the server  100 , the infrastructure sensor  200 , and the in-vehicle device  300  will be described below. 
     In the server  100 , the vehicle linkage unit  101  has a function of communicating with the in-vehicle device  300 , receives position information and route information about the host vehicle transmitted from the in-vehicle device  300 , and transmits information about a detour route determined by the route designing unit  109  to the in-vehicle device  300 . The vehicle linkage unit  101  can communicate with the in-vehicle device  300  using, for example, a mobile communication network (such as 4G or 5G). 
     The vehicle route storage unit  102  stores and manages the route information received by the vehicle linkage unit  101  from the in-vehicle device  300  for each vehicle. Note that the route of the traveling route of each vehicle may be designed on the server  100  side using the route designing unit  109 , instead of being designed on the in-vehicle device  300  side. In such a case, the vehicle route storage unit  102  stores and manages the route information about the traveling route of each vehicle designed by the route designing unit  109  for each vehicle. The vehicle route storage unit  102  manages the traveling route of each vehicle, for example, by storing and holding the route information about each vehicle in combination with a unique vehicle ID set to each vehicle in advance. As will be described later, when a detour route is set by the route designing unit  109 , the contents of the route information stored in the vehicle route storage unit  102  are updated according to the detour route. 
     The infrastructure linkage unit  103  has a function of communicating with the infrastructure sensor  200 , and receives information transmitted from the infrastructure sensor  200  and transmits information to the infrastructure sensor  200 . The infrastructure linkage unit  103  can communicate with the infrastructure sensor  200  using, for example, a mobile communication network (such as 4G or 5G) or a fixed line. 
     When an obstacle is detected in sensing information received and acquired from any of the infrastructure sensors  200  by the infrastructure linkage unit  103 , the affected route identification unit  104  identifies an affected route as a traveling route on which the vehicle is affected by the obstacle, based on the position of each infrastructure sensor  200  stored and managed by the infrastructure management unit  105 . In this process, the affected route identification unit  104  acquires, from the infrastructure management unit  105 , the position of the infrastructure sensor  200  that has transmitted the sensing information including the obstacle information to the server  100 , for example. Then, the position of the obstacle is identified based on the position of the infrastructure sensor  200  and the sensing information, and the road on which the obstacle exists is identified. Once the road on which the obstacle exists is thus identified, a traveling route including the road on which the obstacle exists, among the traveling routes of the vehicles stored and managed by the vehicle route storage unit  102 , is identified as the affected route on which the vehicle is affected by the obstacle. The infrastructure management unit  105  may manage a link ID of a road corresponding to a sensing range of each infrastructure sensor  200 , instead of the position of each infrastructure sensor  200 . In this case, the road on which an obstacle exists can be identified with the affected route identification unit  104  acquiring, from the infrastructure management unit  105 , the link ID corresponding to the infrastructure sensor  200  that has transmitted the sensing information including the obstacle information to the server  100   
     Based on the affected route identified by the affected route identification unit  104 , the affected vehicle identification unit  106  identifies as an affected vehicle, a vehicle to be affected by an obstacle among a plurality of vehicles including the in-vehicle device  300 . In this process, the affected vehicle identification unit  106  selects as the affected vehicle, for example, a vehicle traveling toward the obstacle from among the vehicles corresponding to the affected route, based on the position information about each vehicle stored in the vehicle information storage unit  107 . 
     The vehicle information storage unit  107  stores and manages the position information received from the in-vehicle device  300  by the vehicle linkage unit  101  for each vehicle, and also stores vehicle information related to the characteristics of each vehicle. Each vehicle information includes, for example, information about the width and the height of the vehicle. As in the case of the vehicle route storage unit  102  described above, the vehicle information storage unit  107  preferably manages the information about each vehicle, for example, by storing and holding the position information and the vehicle information about each vehicle in combination with a unique vehicle ID set to each vehicle in advance. With this configuration, the traveling route of each vehicle can easily be associated with the position and characteristics of the vehicle, using the vehicle ID. 
     The passing ability determination unit  108  determines whether the affected vehicle, identified by the affected vehicle identification unit  106 , can pass by the obstacle. In this process, for example, the passing ability determination unit  108  determines whether the affected vehicle can pass by the obstacle, based on the information about the vehicle width of the affected vehicle stored in the vehicle information storage unit  107  as the vehicle information and about a passable width of the road through which the vehicle passes at an obstacle point where the obstacle exists. Details of this determination method will be described later. 
     The route designing unit  109  designs a detour route for the affected vehicle to travel while avoiding the obstacle point using the map information  110  when the passing ability determination unit  108  determines that the affected vehicle is unable to pass by the obstacle. For example, the detour route is designed by acquiring the current position of the affected vehicle by reading the latest position information about the affected vehicle from the vehicle information storage unit  107 , and searching for a route through which the vehicle reaches the destination from the acquired current position without passing through the obstacle point. When there is no available detour road between the current position of the affected vehicle and the obstacle point, a detour route involving returning to a point where a road on which the obstacle point can be avoided can be accessed may be searched. When a plurality of detour routes can be designed, a detour route may be designed with a higher priority given to a road provided with more infrastructure sensors  200 . The information about the detour route designed by the route designing unit  109  is transmitted by the vehicle linkage unit  101  to the in-vehicle device  300  installed in the affected vehicle. 
     The map information  110  is information representing a map of an area where the host vehicle moves autonomously, and is stored in a storage such as an HDD or an SSD in the server  100 . The map information  110  includes, for example, road map information about various parts of the country, information about a map in a parking lot, and the like. It should be noted that the map information  110  used preferably features higher accuracy than general map information used in a conventional navigation device or the like, so that a route on which the host vehicle can move autonomously can be appropriately set based on the map information  110 . 
     The display unit  111  uses the route information about each vehicle stored in the vehicle route storage unit  102 , the position information about each vehicle stored in the vehicle information storage unit  107 , the map information  110 , and the like to display a screen to an administrator of the server  100 . Note that the display unit  111  may not necessarily be a component of the server  100 , and may be provided outside the server  100 . The display unit  111  includes, for example, a liquid crystal display, and can display and provide various screens necessary for the administrator of the server  100  to manage the operations of the vehicle assistance system  1 . For example, when an obstacle is detected by any of the infrastructure sensors  200  and a detour route for avoiding the obstacle is set, such information can be displayed on the screen to be checked by the administrator. An example of such a screen will be described later. 
     The sensor unit  201  of the infrastructure sensor  200  includes various sensors such as a camera, a radar, and Light Detection and Ranging (LiDAR). The sensor unit  201  generates sensing information within a predetermined sensing range corresponding to these sensors based on the position where the infrastructure sensor  200  is installed. When the sensor unit  201  detects an obstacle existing within the sensing range, the sensing information includes information about the obstacle. 
     The infrastructure-side server linkage unit  202  has a function of communicating with the server  100 , and transmits the sensing information generated by the sensor unit  201  to the server  100 . The infrastructure-side server linkage unit  202  can communicate with the infrastructure linkage unit  103  of the server  100 , by using, for example, a mobile communication network (such as 4G or 5G) or a fixed line. 
     In the in-vehicle device  300 , the vehicle-side server linkage unit  301  has a function of communicating with the server  100 , and transmits the position information and the route information about the host vehicle to the server  100 , and receives information about the detour route transmitted from the server  100 . The vehicle-side server linkage unit  301  can communicate with the vehicle linkage unit  101  of the server  100 , by using, for example, a mobile communication network (such as 4G or 5G). 
     The route management unit  302  manages the current traveling route of the host vehicle. As described above, when the route designing unit  109  designs a detour route in the server  100 , and information about the detour route is transmitted from the server  100  and received by the vehicle-side server linkage unit  301 , the route management unit  302  discards the current traveling route, and sets the detour route to be the new traveling route of the host vehicle based on the received information. 
     The vehicle-side route designing unit  303  designs the traveling route on which the host vehicle autonomously travels from the current position to the set destination, based on the map information  306  and the current position of the host vehicle determined by the vehicle position determination unit  307 . The traveling route of the host vehicle designed by the vehicle-side route designing unit  303  is stored and managed in the route management unit  302 . When the traveling route of each vehicle is designed in the server  100  as described above, the in-vehicle device  300  may not include the vehicle-side route designing unit  303 . 
     The vehicle-side display control unit  304  generates a screen displayed by the vehicle-side display unit  305 , based on the map information  306  and the traveling route of the host vehicle managed by the route management unit  302 . The vehicle-side display unit  305  includes, for example, a liquid crystal display, and displays a screen generated by the vehicle-side display control unit  304  to issue a notification to an occupant of the host vehicle. As a result, for example, the vehicle-side display unit  305  displays a screen showing the position and traveling route of the host vehicle on a map, or a screen for notifying an occupant of the host vehicle of a detour route when the detour route for avoiding an obstacle is set. Note that a notification to the occupant may be issued with sound output from a speaker (not illustrated) in addition to/instead of the screen of the vehicle-side display unit  305 . 
     As in the case of the map information  110  of the server  100 , the map information  306  is information representing a map of an area where the host vehicle autonomously moves, and is stored in an unillustrated storage such as an HDD or an SSD in the in-vehicle device  300 . The map information  306  is used, for example, by the vehicle-side route designing unit  303  for designing the traveling route of the host vehicle, by the vehicle-side display control unit  304  for generating a map screen, and the like. Note that the map information  306  used preferably features higher accuracy than conventional general map information, as in the case of the map information  110  of the server  100 . 
     The vehicle position determination unit  307  determines the position of the host vehicle based on a GPS signal received by a GPS sensor (not illustrated) and information (such as speed, acceleration, and steering amount) about a moving status of the host vehicle detected by the in-vehicle sensor  31 . Note that the map information  306  may be used to perform known map matching processing so that the position of the host vehicle is set to be on a road. The position information about the host vehicle determined by the vehicle position determination unit  307  is transmitted to the server  100  by the vehicle-side server linkage unit  301  and used by the vehicle information storage unit  107  for managing the position of the host vehicle. 
     The vehicle control unit  308  performs control required for causing autonomous movement of the host vehicle along the current traveling route, based on that map information  306  the current position of the host vehicle determined by the vehicle position determination unit  307  and the traveling route of the host vehicle managed by the route management unit  302 . For example, the vehicle control unit  308  determines the speed, acceleration, and steering amount of the host vehicle based on the length and curvature of the traveling route, and controls a drive unit  32  to perform accelerator operation, brake operation, steering wheel operation, and the like of the host vehicle, so that the host vehicle can travel along the traveling route. In this process, for example, information about the periphery of the host vehicle acquired from the in-vehicle sensor  31  may further be used, to determine to perform emergency braking when an obstacle is detected in front of the host vehicle. 
     Next, a specific example of autonomous movement assistance performed by the vehicle assistance system  1  according to the present embodiment will be described with reference to  FIGS. 2 and 3 . 
       FIG. 2  is a sequence diagram illustrating autonomous movement assistance control performed by the vehicle assistance system  1 . 
     In step S 101 , the infrastructure sensor  200  determines whether there is an obstacle in the sensing range based on the sensing information generated by the sensor unit  201 . When there is no obstacle, that is, when no obstacle is detected by the sensor unit  201 , the processing stays at step S 101 . When there is an obstacle, that is, when an obstacle is detected by the sensor unit  201 , the processing proceeds to step S 102 . 
     In step S 102 , the infrastructure-side server linkage unit  202  of the infrastructure sensor  200  transmits the sensing information generated by the sensor unit  201  to the server  100 . The server  100  receives the sensing information transmitted from the infrastructure sensor  200  through the infrastructure linkage unit  103 . 
     In steps S 101  and S 102  described above, the infrastructure sensor  200  determines whether there is an obstacle and the infrastructure sensor  200  transmits the sensing information to the server  100  when it is determined that there is an obstacle. Alternatively, the server  100  may determine whether there is an obstacle. In such a case, the infrastructure sensor  200  may transmit sensing information to the server  100  at a predetermined interval, and the server  100  that has received the sensing information may determine whether there is an obstacle based on the sensing information. As a result, when it is determined that there is an obstacle, the server  100  executes processing from step S 103  described below. 
     In step S 103 , the affected route identification unit  104  and the affected vehicle identification unit  106  of the server  100  identify the affected vehicle affected by the obstacle included in the sensing information received in step S 102 . In this process, as described above, first of all, the affected route identification unit  104  identifies the position of the obstacle and identifies the affected route on which the vehicle is affected by the obstacle. Then, the affected vehicle identification unit  106  identifies an affected vehicle that corresponds to the identified affected route and is traveling toward the obstacle. 
     In step S 104 , the server  100  determines whether an affected vehicle is identified in step S 103 . When at least one affected vehicle is identified for the obstacle, the processing proceeds to step S 105 . When no vehicle is identified, the sequence in  FIG. 2  is terminated. 
     In step S 105 , the passing ability determination unit  108  of the server  100  acquires the vehicle width of each affected vehicle identified in step S 103 . In this process, for example, the passing ability determination unit  108  acquires feature information of each affected vehicle from the vehicle information storage unit  107 , and acquires the vehicle width of each affected vehicle based on the vehicle width information included in the feature information. 
     In step S 106 , the passing ability determination unit  108  of the server  100 , determines a vehicle control width of each affected vehicle identified in step S 103 . The vehicle control width is the minimum distance that needs to be secured between the left and right side surfaces of the vehicle and walls and obstacles for the autonomous driving control of the vehicle. This width varies depending on the control accuracy of the vehicle, the control interval, and the like. In this process, for example, the passing ability determination unit  108  acquires vehicle information of each affected vehicle from the vehicle information storage unit  107 , and determines the vehicle control width of each affected vehicle based on the vehicle width information included in the vehicle information. Alternatively, a preset value may be used as the vehicle control width of each affected vehicle. Other suitable methods may be used for determining the vehicle control width of each affected vehicle. 
     In step S 107 , the passing ability determination unit  108  of the server  100  determines whether each affected vehicle can pass by the obstacle based on the vehicle width acquired in step S 105  and the vehicle control width determined in step S 106 . In this process, the passing ability determination unit  108  performs the determination in step S 107  as follows, for example. 
       FIG. 3  is a diagram illustrating passing ability determination processing executed by the passing ability determination unit  108 .  FIG. 3  illustrates a state where, for example, a passing vehicle  42  is about to pass by a parked vehicle  40  existing as an obstacle at obstacle coordinates  41  on the road. In this case, in the server  100 , the passing vehicle  42  is identified as an affected vehicle that is affected by the parked vehicle  40 , and the passing ability determination unit  108  executes the passing ability determination processing in step S 107  of  FIG. 2 . In this processing, first of all, the passing ability determination unit  108  calculates a value obtained by adding the vehicle control width to both left and right sides of the vehicle width of the passing vehicle  42  illustrated in the figure, as a passing width of the passing vehicle  42 , and compares the value with a passable width of the road. In this process, the server  100  can calculate the passable width by, for example, obtaining a distance from the obstacle coordinates  41  to the center of the road, subtracting a half of the vehicle width of the parked vehicle from the distance, adding a half of the road width to the resultant value to obtain a gap between the parked vehicle and a road edge, adding the vehicle width of the parked vehicle to the gap, and subtracting the resultant value from the road width. Alternatively, the infrastructure sensor  200  may store road width information in advance, so that the passable width of the road can be detected on the side of the infrastructure sensor  200  by using the value, the position of the obstacle detected, and the vehicle width. As a result, when the passable width of the passing vehicle  42  is equal to or less than the passing width, it is determined that the passing vehicle  42  can pass by the parked vehicle  40 . When the passing width is larger than the passable width, the passing vehicle  42  is determined to be incapable of passing by. 
     In step S 107  in  FIG. 2 , it is determined whether each affected vehicle can pass by the obstacle by the method described above. As a result, when it is determined that the vehicle can pass, the processing proceeds to step S 108 . When it is determined that the vehicle cannot pass, the processing proceeds to step S 110 . Note that the processing in and after step S 108  is executed for each affected vehicle according to a result of the determination in step S 107 . 
     In step S 108 , the vehicle linkage unit  101  of the server  100  transmits the information about the obstacle point used in the passing ability determination processing in step S 107 , to the in-vehicle device  300  installed in the affected vehicle. For example, information about the coordinate value of the obstacle and the passable width is transmitted as the information about the obstacle point. The of the vehicle-side server linkage unit  301  of the in-vehicle device  300  receives the information about the obstacle point transmitted from the server  100 . 
     In step S 109 , the in-vehicle device  300  performs control of causing the host vehicle to pass by the obstacle based on the information about the obstacle point received from the server  100  in step S 108 . In this process, the in-vehicle device  300  controls the movement status of the host vehicle based on the coordinate value of the obstacle and the information about the passable width included in the information about the obstacle point, so that the host vehicle that has reached the vicinity of the obstacle can appropriately pass by the obstacle. Furthermore, in this process, a screen for notifying the occupant of the host vehicle of the presence of an obstacle may be displayed on the vehicle-side display unit  305 . When the vehicle successfully passes through the obstacle point, the sequence in  FIG. 2  is terminated. 
     In step S 110 , the route designing unit  109  of the server  100  designs the detour route for the affected vehicle. Here, as described above, the map information  110  is used to design a detour route on which the affected vehicle can travel while avoiding the obstacle point. 
     In step S 111 , the vehicle linkage unit  101  of the server  100  transmits the information about the detour route designed in step S 110  to the in-vehicle device  300  installed in the affected vehicle. Furthermore, in this process, notification information for notifying the occupant of the affected vehicle of a reason why the traveling route of the affected vehicle is changed to the detour route is preferably transmitted together with the detour route information. However, if the affected vehicle obviously has not occupant, the transmission of the notification information may be omitted. The vehicle-side server linkage unit  301  of the in-vehicle device  300  receives the detour route information and the notification information transmitted from the server  100 . 
     In step S 112 , the in-vehicle device  300  updates the route information about the host vehicle stored in the route management unit  302  based on the detour route information received from the server  100  in step S 111 . As a result, the current traveling route of the host vehicle is overwritten by the detour route, and the vehicle control unit  308  performs control to cause the host vehicle that is an affected vehicle to travel along the detour route. 
     In step S 113 , the vehicle-side display unit  305  of the in-vehicle device  300  display a screen for notifying the occupant of the host vehicle of the reason why the traveling route is changed to the detour route based on the notification information received from the server  100  in step S 111 . For example, the position of the obstacle and the planned traveling route are displayed on the map, and the fact that the vehicle cannot pass by the obstacle is notified as the reason for changing to the detour route. 
     In step S 114 , a management screen of the display unit  111  of the server  100  displays the detour route designed for each affected vehicle in step S 110 . The management screen is a screen for the administrator of the server  100  to manage the operation of the vehicle assistance system  1  as described above. When a detour route is set due to an obstacle, the detour route is displayed on the management screen. 
       FIG. 4  is a diagram illustrating an example of the management screen displayed on the display unit  111 .  FIG. 4  illustrates a state where a traveling route  52  is set from a starting point  50  to a destination  51 , and an obstacle  54  on the traveling route  52  is detected ahead of a vehicle  53  traveling along the traveling route  52  by an infrastructure sensor  55  installed in the periphery. In this state, when the server  100  determines, in the processing in  FIG. 2 , that the vehicle  53  cannot pass by the obstacle  54 , the server  100  designs a detour route  56  for the vehicle  53  to avoid the obstacle  54 . In the management screen illustrated in  FIG. 4 , the traveling route  52  and the detour route  56  are displayed to be distinguishable from each other, so that the administrator can easily recognize that the detour route  56  has been designed. 
       FIG. 5  is a diagram illustrating another example of the management screen displayed on the display unit  111 .  FIG. 5  illustrates a state where the traveling route  52  is set from the starting point  50  to the destination  51 , and the obstacle  54  on the traveling route  52  is detected ahead of three vehicles  53   a ,  53   b , and  53   c  each traveling along the traveling route  52 , by the infrastructure sensor  55  installed in the periphery. In this state, when the server  100  determines, in the processing in  FIG. 2 , that the vehicles  53   a  and  53   b  cannot pass by the obstacle  54 , the server  100  designs the detour route  56  for the vehicles  53   a  and  53   b  to avoid the obstacle  54 . On the other hand, when it is determined that the vehicle  53   c  can pass by the obstacle  54 , the detour route  56  is not designed for the vehicle  53   c . In the management screen illustrated  FIG. 5 , the traveling route  52  and the detour route  56  are displayed in an distinguishable manner, and the vehicles  53   a  and  53   b  corresponding to the detour route  56  and the vehicle  53   c  not corresponding to the route are displayed in different colors so as to be distinguishable with each other, so that the administrator can easily recognize the vehicle for which the detour route  56  has been designed. 
     According to the first embodiment of the present invention described above, the following operations and effects are obtained. 
     (1) The vehicle assistance system  1  includes the server  100  capable of communicating with a plurality of vehicles, the plurality of in-vehicle devices  300  each installed in each of the plurality of vehicles, and the infrastructure sensor  200  that generates sensing information about an obstacle point at which an obstacle exists on a road. The server  100  includes the infrastructure linkage unit  103  that has a function of communicating with the infrastructure sensor  200  and acquires the sensing information from the infrastructure sensor  200 , the affected vehicle identification unit  106  that identifies a vehicle that is affected by the obstacle, among a plurality of vehicles, as an affected vehicle, the passing ability determination unit  108  that determines whether the affected vehicle is capable of passing by the obstacle, based on a vehicle width of the affected vehicle and a passable width of the road at the obstacle point based on the sensing information, the route designing unit  109  that designs a detour route on which the affected vehicle travels to avoid the obstacle point, when the passing ability determination unit  108  determines the affected vehicle is not capable of passing, and the vehicle linkage unit  101  that has a function of communicating with a plurality of in-vehicle devices  300  and transmits information about the detour route to the in-vehicle device  300  installed in the affected vehicle among the plurality of in-vehicle devices  300 . The infrastructure sensor  200  includes the sensor unit  201  that detects an obstacle and generates sensing information, and the infrastructure-side server linkage unit  202  that transmits the sensing information to the server  100 . The in-vehicle device  300  includes the vehicle-side server linkage unit  301  that acquires information about a detour route from the server  100 , and the vehicle control unit  308  that causes the host vehicle, which is the affected vehicle, to travel along the detour route based on the information about the detour route acquired by the vehicle-side server linkage unit  301 . With this configuration, when an obstacle exists on a road, appropriate assistance can be provided to a vehicle affected by the obstacle. 
     (2) The vehicle linkage unit  101  transmits information about the obstacle point to the in-vehicle device  300  (step S 108 ) when the passing ability determination unit  108  determines the affected vehicle is capable of passing (step S 107 : Yes). With this configuration, the in-vehicle device  300  that has received the information can issue a notification in advance that indicates that the vehicle needs to pass by the obstacle. 
     (3) The passing ability determination unit  108  determines a vehicle control width required for controlling the affected vehicle (step S 106 ), and determines whether the affected vehicle is capable of passing by the obstacle, by comparing the passable width with a value obtained by adding the vehicle control width to the vehicle width (step S 107 ). With this configuration, whether the affected vehicle can pass by the obstacle can be reliably determined, with the vehicle control width required for controlling autonomous driving of the affected vehicle taken into consideration. 
     (4) The vehicle linkage unit  101  may further transmit information for notifying the occupant of the affected vehicle of a reason why the traveling route of the affected vehicle is changed, to the detour route to the in-vehicle device  300  (step S 111 ). With this configuration, when an occupant is on the affected vehicle, the occupant can be notified of the change to the detour route in advance in a clearly recognizable manner. 
     (5) The route designing unit  109  may design the detour route with a road provided with the infrastructure sensor  200  prioritized (step S 110 ). With this configuration, even when another obstacle appears while the vehicle is traveling on the detour route, the obstacle can be detected in advance for designing a further detour route. 
     Second Embodiment 
       FIG. 6  is a diagram illustrating a configuration of a vehicle assistance system according to a second embodiment of the present invention. A vehicle assistance system  1 A illustrated in  FIG. 6  includes the server  100 , the infrastructure sensor  200 , and an in-vehicle device  300 A, and assists a host vehicle in which the in-vehicle device  300 A is installed when the vehicle autonomously travels, by autonomous driving, on a traveling trajectory to a designated location, as in the case of the vehicle assistance system  1  described in the first embodiment. The vehicle assistance system  1 A according to the present embodiment is different from the vehicle assistance system  1  according to the first embodiment in that the in-vehicle device  300 A further includes an inter-vehicle communication unit  309 . Hereinafter, the vehicle assistance system  1 A according to the present embodiment will be described while focusing on this difference. 
     The inter-vehicle communication unit  309  performs inter-vehicle communications, through wireless communications, with other vehicles in the periphery of the host vehicle (for example, other vehicles traveling behind the host vehicle). With the inter-vehicle communications performed by the inter-vehicle communication unit  309 , for example, information about an obstacle point or information about a detour route received by a certain vehicle from the server  100  can be transferred to another vehicle. With this configuration, the server  100  can distribute the information about the obstacle point and the information about the detour route to all the affected vehicle by communicating only with the in-vehicle device  300 A installed in some of the affected vehicles. 
     When using the inter-vehicle communications to transmit the information about the obstacle point and the information about the detour route from one vehicle (first vehicle) to another vehicle (second vehicle), the vehicle linkage unit  101  of the server  100  transmits these pieces of information to the in-vehicle device  300 A of the first vehicle together with a predetermined command. This command is a command for causing the inter-vehicle communication unit  309  to transmit the information about the obstacle point and the information about the detour route to other vehicles by using its inter-vehicle communication function. The in-vehicle device  300 A of the first vehicle that has received the command causes the inter-vehicle communication unit  309  to transmit the information about the obstacle point and the information about the detour route received, to other vehicles through the inter-vehicle communications, in response to the command. 
     According to the second embodiment of the present invention described above, the in-vehicle device  300 A includes the inter-vehicle communication unit  309  that implements the inter-vehicle communication function for communicating with other vehicles. The vehicle linkage unit  101  further transmits, to the in-vehicle device  300 A, the command for causing the inter-vehicle communication unit  309  to transmit the information about the detour route to another vehicle. The in-vehicle device  300 A causes the inter-vehicle communication unit  309  to transmit the information about the detour route to the in-vehicle device  300 A installed in another vehicle, in response to the command. With this configuration, even if an affected vehicle that cannot pass by an obstacle is in an area where the communications with the server  100  are disabled, or the computing capacity of the server  100  is insufficient, the information about the detour route can be transmitted from the server  100  to the affected vehicle. 
     In each of the embodiments of the present invention described above, it is assumed that no particular processing is executed after each affected vehicle has passed by the obstacle or has avoided the obstacle by traveling on the detour route. However, a result of avoiding the obstacle may be fed back from the in-vehicle device  300 ,  300 A to the server  100 , for improving the passing ability determination processing by the server  100  thereafter. For example, the in-vehicle device  300 ,  300 A may feed back, to the server  100 , information such as: whether or not the affected vehicle actually succeeded in passing by the obstacle; if succeeded, a distance indicating how much extra space there was with respect to the obstacle or the edge of the road; an action taken when the vehicle was incapable of passing; and whether the detour route was appropriate when the vehicle traveled on the detour route. The information fed back is reflected on the vehicle information stored and managed in the vehicle information storage unit  107  in the server  100 , to be reflected on the passing ability determination processing executed by the passing ability determination unit  108 , whereby the accuracy of the passing ability determination processing is improved. 
     Furthermore, in each of the embodiments of the present invention described above, an example is described in which the passing ability determination unit  108  determines whether each affected vehicle can pass based on comparison between the passing width of each affected vehicle and the passable width of the road as in the determination method described with reference to  FIG. 3 . It should be noted that other conditions may be further added for the determination. For example, whether or not each affected vehicle can pass can be determined while taking a height restriction, a traffic congestion state, a road surface condition, and the like, in the vicinity of the obstacle point into consideration. With this configuration, for example, when there is snow piled up high on the side of the road, whether each affected vehicle can pass is determined under the condition that the vehicle cannot pass through the snow covered portion. In this manner, whether each affected vehicle can pass can be even more accurately determined, with the actual condition of the obstacle point reflected on the determination. 
     In each of the embodiments described above, an example is described in which each vehicle in which the in-vehicle device  300  or  300 A is installed autonomously moves, by autonomous driving, along a traveling route to a designated location. However, the present invention is not limited to this. Specifically, the present invention is not limited to an autonomous driving vehicle, and can also be applied to a normal vehicle in which a driver performs a driving operation. When the present invention is applied to a normal vehicle, displaying of a map showing the traveling route and the detour route set on the vehicle-side display unit  305  and the like are preferably performed to notify the driver of the routes. Furthermore, when the present invention is applied to a normal vehicle, the passing ability determination unit  108  preferably determines whether the vehicle can pass by the obstacle by using a distance (clearance) between the vehicle and the obstacle generally required for the driver to perform the driving operation, instead of using the vehicle control width. 
     The embodiments and modifications described above are merely examples, and the present invention is not limited to the contents of these, as long as the features of the invention are not compromised. Moreover, although various embodiments and modifications are described above, the present invention is not limited to the contents of these. Other aspects conceivable within the scope of the technical idea of the present invention are also included in the scope of the present invention.