Patent ID: 12202474

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

1. Configuration of Road Information Processing System

A configuration of a road information processing system1of the present embodiment will be described with reference toFIG.1. The road information processing system1is a computer system including a processor10, a memory20, a communication unit30, etc.

The road information processing system1uses the communication unit30to allow communication between a road management server110and a vehicle50traveling on a road within an area Ar, via a communication network100. The area Ar is an area in which communication with the road information processing system1is available. The vehicle50has a camera51for capturing a forward view, sensors52for detecting a behavior of the vehicle50, an alarm device53for outputting an alarm to a driver of the vehicle50, and an electronic control unit (ECU)55for controlling an operation of the vehicle50.

The ECU55has a lane departure prevention function that recognizes divider lines92,93,94of the road from an image of a forward view of the vehicle50captured by the camera51, monitors a departure of the vehicle50from an own lane90to an opposing lane91, and executes a departure prevention process. Upon detection of the departure of the vehicle50from the own lane90, the ECU55executes a process for warning the driver by outputting an alarm from the alarm device53, as the lane departure prevention process. The alarm device53is a display, a speaker, etc. to output an alarm indication to the display, a warning sound or the like from the speaker, as an alarm.

When the alarm was output by the lane departure prevention function, the ECU55transmits, to the road information processing system, lane departure prevention information dvi indicating a state when the alarm was output. The lane departure prevention information dvi includes information about a time point (period) when the alarm was output, and a point where the alarm was output.

The sensors52for detecting the behavior of the vehicle50include a global navigation satellite system (GNSS) sensor for detecting the current location of the vehicle50, a 3-axis acceleration sensor, a 3-axis gyro sensor (angular velocity sensor), a steering angle sensor, etc. The ECU55transmits, to the road information processing system1, vehicle behavioral information bhi indicating a behavioral state of the vehicle50detected by the sensors52when the alarm was output by the lane departure prevention function.

The processor10of the road information processing system1reads and executes a control program21stored in the memory20, thereby functioning as a lane departure prevention information acquisition unit11, a vehicle behavioral information acquisition unit12, a lane departure degree recognition unit13, and an obstacle recognition unit14.

The lane departure prevention information acquisition unit11receives and acquires, through the communication unit30, the lane departure prevention information dvi transmitted from the vehicle50. The vehicle behavioral information acquisition unit12receives and acquires, through the communication unit30, the vehicle behavioral information bhi transmitted from the vehicle50. The lane departure degree recognition unit13recognizes, based on the lane departure prevention information dvi and the vehicle behavioral information bhi, the degree of departure of the vehicle50from the own lane90when the alarm was output by the lane departure prevention function.

The lane departure degree recognition unit13recognizes an obstacle present on the road by recognizing, based on the lane departure prevention information dvi and the vehicle behavioral information bhi, the behavior of the vehicle50when the alarm was output by the lane departure prevention function of the vehicle50. The obstacle is, for example, a parked vehicle, a place under construction, etc. InFIG.1, a vehicle60parked without leaving enough space, which is parked without leaving enough space for allowing traveling on the right side of the own lane90(opposing lane side) is shown as an example.

In recent years, vehicles having a lane departure prevention function similar to that of the vehicle50are widespread, and the lane departure prevention information dvi and the vehicle behavioral information bhi are transmitted to the road information processing system1from these vehicles traveling on roads within the area Ar. The road information processing system1can recognize, based on the lane departure prevention information dvi and the vehicle behavioral information bhi transmitted from these vehicles, an obstacle present on a road within a wide range of area Ar.

2. Obstacle Information Acquisition Process

According to the flowchart shown inFIG.2, a process for acquiring information about an obstacle present on a road, which is executed by the road information processing system1in the state shown inFIG.1, will be explained. The road information processing system1recognizes an obstacle present on a road on which the vehicle50is traveling.

In step S1inFIG.2, the lane departure prevention information acquisition unit11receives and acquires, through the communication unit30, the lane departure prevention information dvi transmitted from the vehicle50to be monitored (hereinafter referred to as the subject vehicle50). In subsequent step S2, the vehicle behavioral information acquisition unit12receives and acquires, through the communication unit30, the vehicle behavioral information bhi transmitted from the subject vehicle50.

In subsequent step S3, the obstacle recognition unit14recognizes, from the lane departure prevention information dvi, a period in which an alarm was output by the lane departure prevention function of the subject vehicle50. In the next step S4, the obstacle recognition unit14recognizes, from the vehicle behavioral information bhi, a behavior (road-width-direction behavior) of the subject vehicle50in a direction Dr of the road width (seeFIG.1) in the period in which the alarm was output by the lane departure prevention function. The obstacle recognition unit14recognizes the road-width-direction behavior, based on information included in the vehicle behavioral information bhi, such as an angular velocity, acceleration, and steering angle, detected by the sensors52of the subject vehicle50.

In the next step S5, the obstacle recognition unit14determines whether a behavior of the subject vehicle50returning to the own lane90was recognized from the road-width-direction behavior. Then, the obstacle recognition unit14proceeds to step S20if the behavior returning to the own lane90was recognized, or proceeds to step S6if the behavior returning to the own lane90was not recognized.

In step S20, the obstacle recognition unit14determines whether an elapsed time from a time point at which outputting an alarm by the lane departure prevention function was started to a time point at which the behavior of the subject vehicle50returning to the own lane90occurred is a predetermined time or more. Then, the obstacle recognition unit14proceeds to step S6if the elapsed time is equal to or more than the predetermined time, or proceeds to step S21if the elapsed time is less than the predetermined time. In step S21, the obstacle recognition unit14determines that there is no obstacle on the road, and proceeds the process to step S11.

In step S6, the lane departure degree recognition unit13recognizes the degree of departure of the subject vehicle50from the own lane90with reference to the road-width-direction behavior recognized from the vehicle behavioral information bhi.FIG.3shows an example of a state in which a small vehicle61parked without leaving enough space and a large vehicle62parked without leaving enough space are present as obstacles on the own lane90of the subject vehicle50.

As shown inFIG.3, regarding the degree of departure (here, the amount of departure) of the subject vehicle50from the own lane90, a departure amount d2when the subject vehicle50is traveling while avoiding the large vehicle62parked without leaving enough space is more than a departure amount d1when the subject vehicle50is traveling while avoiding the small vehicle61parked without leaving enough space. Moreover, the greater the width W of the own lane90recognized from map data22, the smaller the degree of departure of the subject vehicle50from the own lane90. Therefore, in subsequent step S8, the obstacle recognition unit14estimates that the larger the departure degree of the subject vehicle50from the own lane90recognized by the lane departure degree recognition unit13and the greater the width W of the own lane90, the larger the size of the obstacle.

Note that the width W of the own lane90and the departure amounts d1, d2of the subject vehicle50from the own lane90may be recognized from the image captured by the camera51(seeFIG.1). In this case, for example, the image captured by the camera51when the alarm was output by the lane departure prevention function is included in the vehicle behavioral information bhi, and is transmitted from the vehicle50to the road information processing system.

In subsequent step S9, the obstacle recognition unit14estimates a type of the obstacle from the type estimation conditions given below.

(Estimation Condition 1) The obstacle recognition unit14estimates the type of an obstacle, based on an attribute of a point (recognized from the map data22) where an alarm was output by the lane departure prevention function. For example, when the attribute of the point where the alarm was output by the lane departure prevention function is around a store, the obstacle recognition unit14estimates that the type of the obstacle is a vehicle parked on a shoulder of a road.

(Estimation Condition 2) The obstacle recognition unit14estimates the type of an obstacle, based on the time during which an obstacle present at the same point was continuously recognized a plurality of times based on the lane departure prevention information dvi and the vehicle behavioral information bhi transmitted from a plurality of vehicles. For example, the time during which the obstacle present at the same point was continuously recognized a plurality of times is equal to or less than a short time threshold (for example, one hour), the obstacle recognition unit14estimates that the type of the obstacle is a vehicle parked on a shoulder of a road. Moreover, when the time during which the obstacle present at the same point was continuously recognized a plurality of times is equal to or more than a long time threshold (for example, a few hours), the obstacle recognition unit14estimates that the type of the obstacle is roadwork.

(Estimation Condition 3) The obstacle recognition unit14estimates the type of an obstacle, based on a time point at which the obstacle was recognized (the time point at which an alarm was output by the lane departure prevention function). For example, if the time point at which the obstacle was recognized is Saturday or Sunday, the obstacle recognition unit14estimates that the type of the obstacle is a vehicle parked on a shoulder of a road. Moreover, if the time point at which the obstacle was recognized is at night, the obstacle recognition unit14estimates that the type of the obstacle is roadwork.

In the next step S10, the obstacle recognition unit14transmits the information about the recognized obstacle to the road management server110through the communication unit30. The information about the obstacle includes the time point at which the obstacle was recognized, the point where the obstacle is present, the size of the obstacle, the type of the obstacle, etc. Furthermore, the obstacle recognition unit14may determine, based on the obstacle recognition state (such as the recognized frequency, and the length of the period in which the obstacle was continued to be recognized), that the point where parking a vehicle without leaving enough space occurs frequently is an attention-required point, and may include information about the attention-required point in the obstacle information, and transmit the information to the road management server110.

The cause of frequent occurrence of vehicle parked without leaving enough space may include vehicles which stopped to wait for entering a store. In this case, a traveling vehicle cannot advance without crossing the divider line of the road, and the vehicle needs to cross the divider line and depart from the own lane, and therefore the obstacle recognition unit14determines that the point is an attention-required point.

Moreover, it is supposed that a departure from the own lane by the driver's intentional maneuvering is likely occur at a curve with good visibility, irrespective of the purpose of avoiding an obstacle. Therefore, in a section with a large curvature of the road, a threshold for determining an attention-required point may be set high to prevent the obstacle recognition unit14from erroneously recognizing the presence of an obstacle because of frequent departures, despite the fact that no obstacle is actually present.

The road management server110, for example, defines, based on the obstacle information, that a road at a point where parking a vehicle without leaving enough space occurs frequently is the road requiring improvements, and uses this information for road maintenance in the future. Further, the road management server110may transmit the information about the attention-required point to vehicles that are likely to travel toward the attention-required point where parking a vehicle without leaving enough space occurs frequently. Furthermore, information for guiding a route for avoiding the attention-required point may be transmitted upon a request from a driver.

3. Another Embodiment

In the above embodiment, the road information processing system1is configured by the computer system connected to the communication network100is explained as an example. As another embodiment, a road information processing system may be configured by the ECU55mounted on the vehicle50. In this case, the information about an obstacle recognized by the vehicle50is transmitted from the vehicle50to the road management server110via the communication network100.

In the above embodiment, the road information processing system1includes the lane departure degree recognition unit13, and estimates the size of the obstacle by the process in steps S7to S8inFIG.2, but the road information processing system1may be configured by omitting the lane departure degree recognition unit13.

In the above embodiment, the type of the obstacle is estimated by the process in step S9inFIG.2, but the road information processing system1may be configured by omitting the estimation of the obstacle.

In the above embodiment, as the lane departure prevention process by the lane departure prevention function of the vehicle50, the process for outputting an alarm from the alarm device53is shown as an example. The lane departure prevention process by the lane departure prevention function includes a process for controlling the steering angle of steering of the vehicle50in a direction of returning the vehicle50to the own lane90, and a process for warning the driver by vibrating the steering of the vehicle50as well as outputting an alarm.

In the above embodiment, the obstacle recognition unit14may perform the following processes by calculating a steering angular velocity, based on the detected information from the steering angle sensor, included in the vehicle behavioral information bhi. The steering angular velocity is the amount of change of the steering angle per unit time, which is detected by the steering angle sensor.

Process1: Recognizing whether or not there is an obstacle, based on the magnitude of the steering angular velocity. That is to say, when the steering angular velocity is greater than a predetermined velocity, it is determined that the operation is not for avoiding the obstacle, and may be excluded from the subject of determination as to whether there is an obstacle.

Process2: Determining the type of an obstacle, based on the magnitude of the steering angular velocity. That is to say, when the steering angular velocity is greater than the predetermined velocity, it may be possible to estimate that there was an obstacle that was hard to predict and appeared momentarily, such as a sudden appearance. Moreover, when the steering angular velocity is smaller than the predetermined velocity, it may be possible to estimate that there was a fixed obstacle, such as a parked vehicle or roadwork, which is visible from a distant place.

Note that, in order to facilitate understanding of the invention of the present application,FIG.1is a schematic view in which the configuration of the road information processing system1is divided and shown depending on major processing contents, but the road information processing system1may be configured with other division. Further, the processing of components may be executed by a single hardware unit, or may be executed by a plurality of hardware units. Furthermore, the processing by the respective components in the flowchart shown inFIG.2may be executed by a single program, or may be executed by a plurality of programs.

4. Configurations Supported by Above Embodiment

The above embodiment supports the following configurations.

(Configuration 1) A road information processing system including: a lane departure prevention information acquisition unit for acquiring lane departure prevention information indicating a time point at which a lane departure prevention process by a lane departure prevention function was executed, and a point where the lane departure prevention process was executed, on a vehicle having the lane departure prevention function; a vehicle behavioral information acquisition unit for acquiring vehicle behavioral information indicating a behavior of the vehicle; and an obstacle recognition unit for recognizing, based on the lane departure prevention information and the vehicle behavioral information, an obstacle present at the point where the lane departure prevention process was executed.

According to the road information processing system of configuration 1, it is possible to acquire information about an obstacle on a road in a wide range area, based on the lane departure prevention information and the vehicle behavioral information about a vehicle traveling on an arbitrary road.

(Configuration 2) The road information processing system defined in configuration 1, wherein the obstacle recognition unit recognizes the obstacle, based on a road-width-direction behavior that is a behavior of the vehicle in the width direction of a road on which the vehicle is traveling, during a period in which the lane departure prevention process was executed, the road-width-direction behavior being recognized from the lane departure prevention information and the vehicle behavioral information.

According to the road information processing system of configuration 2, it is possible to recognize the obstacle on the road, based on a behavior of the vehicle in the road width direction that is a direction in which the vehicle departs from own lane and returns to the own lane, during the period in which the vehicle departed from the own lane, and the lane departure prevention process by the lane departure prevention function was executed.

(Configuration 3) The road information processing system defined in configuration 2, wherein the obstacle recognition unit recognizes the obstacle, based on the road-width-direction behavior in a predetermined time from a time point at which the lane departure prevention process was started, within the period in which the lane departure prevention process was executed, the road-width-direction behavior being recognized from the lane departure prevention information and the vehicle behavioral information.

According to the road information processing system of configuration 3, it is possible to estimate whether an obstacle that prevents the vehicle from quickly returning to the own lane is present or not, based on the behavior of the vehicle in the road width direction in the predetermined time from the time point at which the vehicle departed from the own lane, and the lane departure prevention process by the lane departure prevention function was started.

(Configuration 4) The road information processing system defined in configuration 2 or configuration 3, wherein the obstacle recognition unit determines whether the obstacle is present or not, based on whether there is a behavior of the vehicle returning to the own lane, which is recognized from the road-width-direction behavior, or a time point at which the behavior of the vehicle returning to the own lane was recognized from the road-width-direction behavior.

According to the road information processing system of configuration 4, it is possible to estimate from the presence or absence of a behavior of the vehicle returning to the own lane, or a time point at which the behavior of the vehicle returning to the own vehicle was recognized, whether an obstacle that prevents the vehicle from returning to the own lane is present or not.

(Configuration 5) The road information processing system defined in configuration 4, wherein the obstacle recognition unit determines that the obstacle is present if the behavior of the vehicle returning to the own lane was not recognized from the road-width-direction behavior, or if an elapsed time from the start of the lane departure prevention process to the time point at which the behavior of the vehicle returning to the own lane was recognized from the road-width-direction behavior is equal to or more than a predetermined time.

According to the road information processing system of configuration 5, if the behavior of the vehicle returning to the own lane was not recognized, or if the elapsed time from the start of the lane departure prevention process to the time point at which the behavior of the vehicle returning to the own lane was recognized is equal to or more than the predetermined time, it is possible to estimate that an obstacle that prevents the vehicle from returning to the own lane is present.

(Configuration 6) The road information processing system defined in any one of configuration 1 to configuration 5, including a lane departure degree recognition unit for recognizing the degree of departure of the vehicle from an own lane, wherein the obstacle recognition unit estimates a size of the obstacle, based on the degree of departure of the vehicle from the own lane recognized by the lane departure degree recognition unit when the lane departure prevention process was executed.

According to the road information processing system of configuration 6, it is estimated that the larger the size of the obstacle on the road, the larger the degree of departure of the vehicle from the own lane. Therefore, it is possible to estimate the size of the obstacle, based on the degree of departure of the vehicle from the own lane when the lane departure prevention process was executed.

(Configuration 7) The road information processing system defined in any one of configuration 1 to configuration 6, wherein the obstacle recognition unit estimates a type of the obstacle, based on an attribute of the point where the obstacle was recognized.

According to the road information processing system of configuration 7, for example, if the point where the obstacle was recognized is around a store, the type of the obstacle can be estimated as a vehicle parked on a shoulder of the road.

(Configuration 8) The road information processing system as defined in any one of configuration 1 to configuration 7, wherein the obstacle recognition unit estimates a type of the obstacle, based on a time during which the obstacle present at the same point is continuously recognized a plurality of times based on a plurality of pieces of the lane departure prevention information about a plurality of the vehicle, and the vehicle behavioral information.

According to the road information processing system of configuration 8, for example, if the time during which the obstacle present at the same point was recognized is a short time, the type of the obstacle can be estimated as a vehicle parked on a shoulder of the road, and if the time is a long time, the type of the obstacle can be estimated as roadwork.

(Configuration 9) The road information processing system defined in any one of configuration 1 to configuration 8, wherein the obstacle recognition unit estimates a type of the obstacle, based on a time point at which the obstacle was recognized.

According to the road information processing system of configuration 9, for example, if the time point at which the obstacle was recognized is Saturday or Sunday, the type of the obstacle can be estimated as a vehicle parked on a shoulder of the road, and if the time point at which the obstacle was recognized is at night, the type of the obstacle can be estimated as roadwork.

REFERENCE SIGNS LIST

1road information processing system;10processor;11lane departure prevention information acquisition unit;12vehicle behavioral information acquisition unit;13lane departure degree recognition unit;14obstacle recognition unit;20memory;21control program;22map data;50vehicle (own vehicle);51camera;52speaker;53sensors;55ECU;60,61,62parked vehicle;90own lane;92opposing lane; and91,92,93divider line of road.