JP2020163968A - Vehicle drive assisting system - Google Patents

Abstract

To provide a vehicle drive assisting system that is able to achieve both evaluation accuracy of a route cost of a route candidate and reduction of the calculation load thereof.SOLUTION: A vehicle drive assisting system 100 comprises an ECU 10, which is a control device. On the basis of travel road information, the ECU 10 sets a target route on a travel road, and controls a vehicle 1 such that it travels along the target route. The ECU 10 sets a warning area WA extending from one end of the travel road in a width direction to the other end in the width direction. The ECU sets sampling points ST at intervals d1 along a portion included in the warning area WA, and sets sampling points SP at intervals d2 larger than the intervals d1 along the other portion thereof.SELECTED DRAWING: Figure 3

Description

The present invention relates to a vehicle driving support system mounted on a vehicle.

Potential method, spline interpolation function, A star (A *), RRT, state lattice method, etc. are known as algorithms used for setting a vehicle route candidate (that is, a candidate that can be a target route for actually driving a vehicle). ing. In addition, a vehicle driving support system using such an algorithm has also been proposed.

According to the above algorithm, it is possible to set a plurality of route candidates on the travel path of the vehicle. The route cost of each route candidate is calculated from the viewpoint of obstacle avoidance and the like, and one route candidate determined to be appropriate based on the calculation result is selected as the target route. For example, Patent Document 1 discloses a vehicle driving support system in which a plurality of route candidates are set on a grid map and one route candidate is selected based on a movement cost.

International Publication No. 2013/05/1081

The system described in Patent Document 1 calculates the movement cost in all the cells through which the route candidate passes among the plurality of cells of the grid map. Although the method of calculating the route cost at a large number of positions on the route candidate is significant from the viewpoint of improving the evaluation accuracy of the route cost of the route candidate, it entails a large calculation load.

In particular, when a method capable of setting a large number of route candidates such as the state lattice method is used, the calculation load of the route cost may become enormous. Therefore, it has been required to reduce the calculation load and to achieve the evaluation accuracy of the route cost at the same time.

The present invention has been made to solve such a problem, and an object of the present invention is to provide a vehicle driving support system capable of achieving both evaluation accuracy of a route cost of a route candidate and reduction of the calculation load thereof. To do.

In order to solve the above problems, the present invention is a vehicle driving support system mounted on a vehicle, which is a travel path information acquisition device for acquiring travel path information related to a travel path, and a travel path based on the travel path information. A control device that sets a target route and controls the vehicle so as to travel along the target route is provided, and the control device sets a plurality of route candidates on the travel route based on the travel route information, and a plurality of route candidates are set. A plurality of sampling points are set at predetermined intervals along each of the route candidates, the route cost at each of the plurality of sampling points is calculated, and one route candidate from the plurality of route candidates is set as a target route based on the route cost. Further, the control device sets a warning area extending from one end in the width direction to the other side in the width direction of the traveling path, and the first interval is set along the portion of the route candidates included in the warning area. It is characterized in that the sampling point is set by, and the sampling point is set at the second interval larger than the first interval along the other portion.

According to this configuration, the control device sets sampling points at the first interval along the portion of the route candidates included in the caution area. The warning area is set so as to extend from one end in the width direction of the traveling path to the other end in the width direction. Since the first interval is smaller than the second interval, a plurality of sampling points are set in the alert area at a relatively high density. Therefore, if a warning area is set in the vicinity of a target to be watched when the vehicle is driven, it is possible to improve the evaluation accuracy of the route cost in the vicinity of the target.

On the other hand, for other parts of the route candidate (that is, parts not included in the warning area), the control device sets sampling points at the second interval along the other parts. Since the second interval is larger than the first interval, a plurality of sampling points are set in the other portion at a relatively low density. As a result, it becomes possible to reduce the calculation load of the route cost in the other part. Since the density of sampling points is relatively low, the evaluation accuracy of the route cost in the other part is also low, but the influence of the evaluation accuracy on the running of the vehicle in the caution area is relatively small.

That is, according to the above configuration, it is possible to make the evaluation accuracy of the route cost practically sufficient while reducing the calculation load. As a result, it is possible to achieve both the evaluation accuracy of the route cost of the route candidate and the reduction of the calculation load thereof.

In the present invention, preferably, an obstacle information acquisition device for acquiring obstacle information regarding an obstacle on a traveling path is provided, and the control device sets a warning area at a position in the traveling direction of the vehicle rather than the obstacle. It is configured.
According to this configuration, it is possible to set a warning area in a blind spot formed by an obstacle (for example, a stopped vehicle on a traveling road, a pedestrian, a wall, a roadside tree, etc.). That is, a plurality of sampling points are set in the blind spot at a relatively high density. As a result, it is possible to calculate the route cost of the route candidate in consideration of the jumping out of the pedestrian or the like from the blind spot while reducing the calculation load.

In the present invention, preferably, the control device is configured so that the larger the outer shape of the obstacle, the larger the outer shape of the warning area.
The larger the outer shape of the obstacle, the larger the blind spot formed by the obstacle tends to be. According to the above configuration, in the control device, the larger the outer shape of the obstacle, the larger the outer shape of the warning area, so that the portion of the route candidates included in the warning area becomes larger. That is, sampling points are set at a relatively high density in a range including a large blind spot. As a result, when a pedestrian or the like jumps out from the blind spot, it is possible to calculate the route cost of the route candidate in consideration of this jumping out.

It should be noted that the outer shape of the warning area does not need to be continuously increased as the outer shape of the obstacle increases. For example, a form in which the outer shape of the caution area gradually increases as the outer shape of the obstacle increases is also included in the scope of the present invention.

In the present invention, preferably, the control device is configured to increase the outer shape of the warning area according to the type of obstacle.
For example, when the obstacle is a large vehicle such as a freight vehicle or a bus, the blind spot formed by the obstacle tends to be larger than that when the obstacle is a passenger vehicle. According to the above configuration, it is possible to increase the portion of the route candidates in which the sampling points are set at the first interval according to the blind spots that are different for each type of obstacle. As a result, when a pedestrian or the like jumps out from the blind spot, it is possible to calculate the route cost of the route candidate in consideration of this jumping out.

In the present invention, preferably, the control device is configured to set a warning area that overlaps with the pedestrian crossing zone on the track.
According to this configuration, in a pedestrian crossing zone where there is a relatively high possibility that a pedestrian or the like will jump out, it is possible to calculate the route cost of a route candidate in consideration of this jumping out.

In the present invention, preferably, the control device is configured so that the larger the moving speed of the vehicle, the larger the outer shape of the warning area.
The higher the moving speed of the vehicle, the more attention must be paid to the jumping out of pedestrians and the like. According to the above configuration, the control device increases the outer shape of the warning area as the moving speed of the vehicle increases, so that the portion of the route candidates included in the warning area becomes larger. That is, the portion of the route candidates in which the sampling points are set at the first interval becomes large. As a result, when a pedestrian or the like jumps out from the blind spot, it is possible to calculate the route cost of the route candidate in consideration of this jumping out.

It should be noted that the outer shape of the caution area does not need to be continuously increased with the moving speed of the vehicle. For example, a form in which the outer shape of the warning area gradually increases with the moving speed of the vehicle is also included in the scope of the present invention.

According to the present invention, it is possible to provide a vehicle driving support system capable of achieving both the evaluation accuracy of the route cost of a route candidate and the reduction of the calculation load thereof.

It is a block diagram of the vehicle driving support system which concerns on embodiment. It is explanatory drawing of a route candidate and a sampling point. It is explanatory drawing of a route candidate and a sampling point. It is explanatory drawing of a route candidate and a sampling point. It is a flowchart which shows the calculation performed by the ECU of FIG.

Hereinafter, embodiments will be described with reference to the accompanying drawings. In order to facilitate understanding of the description, the same components are designated by the same reference numerals in each drawing, and duplicate description is omitted.

First, the outline of the vehicle driving support system 100 according to the present invention will be described with reference to FIGS. 1 and 2. FIG. 1 is a configuration diagram of a vehicle driving support system 100. FIG. 2 is an explanatory diagram of a route candidate RC and a sampling point SP.

The vehicle driving support system 100 is mounted on the vehicle 1 and provides driving support control for driving the vehicle 1 along a target route. As shown in FIG. 1, the vehicle driving support system 100 includes an ECU (electronic control unit) 10, a plurality of sensors, and a plurality of control systems. The plurality of sensors include a camera 21, a radar 22, a vehicle speed sensor 23 for detecting the behavior of the vehicle 1 and a driving operation by an occupant, an acceleration sensor 24, a yaw rate sensor 25, a steering angle sensor 26, an accelerator sensor 27, and a brake. A sensor 28 is included. Further, the plurality of sensors include a positioning system 29 and a navigation system 30 for detecting the position of the vehicle 1. The plurality of control systems include an engine control system 31, a brake control system 32, and a steering control system 33.

Other sensors include a peripheral sonar that measures the distance and position of the peripheral structure with respect to the vehicle 1, a corner radar that measures the approach of the peripheral structure at the four corners of the vehicle 1, and a vehicle interior of the vehicle 1. An inner camera for shooting the image may be included.

The ECU 10 is an example of a control device according to the present invention. The ECU 10 is composed of a computer including a CPU, a memory for storing various programs, an input / output device, and the like. The ECU 10 executes various calculations based on signals received from a plurality of sensors, and appropriately sets the engine system, brake system, and steering system for the engine control system 31, brake control system 32, and steering control system 33, respectively. Sends a control signal to activate the system.

The ECU 10 performs an operation for specifying a position on the travel path based on the travel path information. The travel path information is information on the travel path on which the vehicle 1 is traveling, and includes, for example, information on the shape of the travel path (straight line, curve, curve curvature), travel path width, number of lanes, lane width, and the like. .. The travel path information is acquired by the camera 21, the radar 22, the navigation system 30, and the like.

FIG. 2 shows how the vehicle 1 is traveling on the travel path 5. The ECU 10 sets a plurality of virtual grid points G _n (n = 1, 2, ... N) on the traveling path 5 existing in the traveling direction of the vehicle 1 by calculation based on the traveling path information. When the direction in which the travel path 5 extends is defined as the x direction and the width direction of the travel path 5 is defined as the y direction, the grid points G _n are arranged in a grid pattern along the x direction and the y direction.

The range in which the ECU 10 sets the grid point G _n extends in front of the vehicle 1 by a distance L along the travel path 5. The distance L is calculated based on the speed of the vehicle 1 at the time of executing the calculation. In the present embodiment, the distance L is a distance (L = V × t) that is expected to travel in a predetermined fixed time t (for example, 3 seconds) at the speed (V) at the time of executing the calculation. However, the distance L may be a predetermined fixed distance (eg, 100 m) or a function of velocity (and acceleration). Further, the width W of the range in which the grid point G _n is set is set to a value substantially equal to the width of the traveling path 5. By setting a plurality of grid points G _{n in} this way, it is possible to specify the position on the travel path 5.

Since the traveling path 5 shown in FIG. 2 is a straight section, the grid points G _n are arranged in a rectangular shape. However, since the grid points G _n are arranged along the direction in which the running path extends, when the traveling path includes a curve section, the grid points G _n are arranged along the curvature of the curve section.

Further, the ECU 10 executes an operation for setting a route candidate RC (that is, a candidate that can be a target route for actually traveling the vehicle 1) based on the travel path information and the obstacle information. Obstacle information includes the presence or absence of obstacles (for example, preceding vehicles, parked vehicles, pedestrians, falling objects, etc.) on the traveling path 5 in the traveling direction of the vehicle 1, its type, size, moving direction, moving speed, and the like. Information about. Obstacle information is acquired by the camera 21 and the radar 22.

The ECU 10 sets a plurality of route candidate RCs by route search using the state lattice method. According to the state lattice method, a plurality of route candidate RCs extending from the starting point P _s while branching toward each grid point G _n existing in the traveling direction of the vehicle 1 are set. The start point P _s is the position of the vehicle 1 at the time of executing the calculation. In the example shown in FIG. 2, since the vehicle 1 is located at the origin of the xy coordinates, the coordinates of the start point P _s are (0,0). The ECU 10 defines a multi-order function in which the y-coordinate has the x-coordinate as a variable, and sets a curve drawn in the xy-coordinate based on the multi-order function as a route candidate RC. The polymorphic function is, for example, a quintic function or a cubic function. FIG. 2 shows route candidates RC _a , RC _b , and RC _c that are a part of a plurality of route candidate RCs set by the ECU 10.

Further, the ECU 10 selects one route candidate RC having the minimum route cost from the plurality of route candidate RCs. Specifically, first, the ECU 10 sets a plurality of sampling points SP along each route candidate RC as shown in FIG. A plurality of sampling points SP are arranged on each route candidate RC at intervals from each other. As an example, FIG. 2 shows sampling points SP set at equal intervals along the entire route candidates RC _a , RC _b , and RC _c .

Next, the ECU 10 calculates the path cost at each sampling point SP. Further, the ECU 10 adds up the route costs at the sampling points SP set along the route candidate RC for each route candidate RC, and divides the total value by the total length of the route candidate RC. The ECU 10 uses the value obtained by the division as the route cost of the route candidate RC. The ECU 10 selects the route candidate RC having the minimum route cost from the plurality of route candidate RCs and sets it as the target route.

Further, the ECU 10 sets the control amount of the speed control and the steering control of the vehicle 1 at each sampling point. The control amount is set based on the speed and steering required to drive the vehicle 1 along the target route, and is also used for calculating the route cost. The ECU 10 transmits a control signal to the engine control system 31, the brake control system 32, and the steering control system 33 based on the control amount.

The camera 21 is an example of a travel path information acquisition device according to the present invention, and is also an example of an obstacle information acquisition device. The camera 21 photographs the surroundings of the vehicle 1 and outputs image data. Based on the image data received from the camera 21, the ECU 10 has an object (for example, a preceding vehicle, a parked vehicle, a pedestrian, a driving path, a lane marking (lane boundary line, a white line, a yellow line), a traffic signal, a traffic sign, Identify stop lines, intersections, etc.). Further, when the object is a vehicle, the ECU 10 specifies the type (large vehicle, passenger vehicle, etc.). The ECU 10 may acquire information on the target object from the outside through transportation infrastructure, vehicle-to-vehicle communication, or the like. Thereby, the type, relative position, moving direction, etc. of the object are specified.

The radar 22 is an example of a travel path information acquisition device according to the present invention, and is also an example of an obstacle information acquisition device. The radar 22 measures the position and speed of an object (particularly, a preceding vehicle, a parked vehicle, a pedestrian, a falling object on the traveling path 5, etc.). As the radar 22, for example, a millimeter wave radar can be used. The radar 22 transmits radio waves in the traveling direction of the vehicle 1, and receives the reflected waves generated by reflecting the transmitted waves by the object. Then, the radar 22 measures the distance between the vehicle 1 and the object (for example, the inter-vehicle distance) and the relative speed of the object with respect to the vehicle 1 based on the transmitted wave and the received wave. In this embodiment, instead of the radar 22, a laser radar, an ultrasonic sensor, or the like may be used to measure the distance to the object and the relative speed. Further, a position and speed measuring device may be configured by using a plurality of sensors.

The vehicle speed sensor 23 detects the absolute speed of the vehicle 1. The acceleration sensor 24 detects the acceleration of the vehicle 1 (vertical acceleration / deceleration in the front-rear direction, lateral acceleration / deceleration in the horizontal direction). The yaw rate sensor 25 detects the yaw rate of the vehicle 1. The steering angle sensor 26 detects the rotation angle (steering angle) of the steering wheel of the vehicle 1. The accelerator sensor 27 detects the amount of depression of the accelerator pedal. The brake sensor 28 detects the amount of depression of the brake pedal.

The positioning system 29 is a GPS system and / or a gyro system, and detects the position of the vehicle 1 (current vehicle position information). The navigation system 30 stores the map information inside, and can provide the map information to the ECU 10. The ECU 10 identifies roads, intersections, traffic signals, buildings, etc. existing around the vehicle 1 (particularly, the traveling direction) based on the map information and the current vehicle position information. The map information may be stored in the ECU 10.

The engine control system 31 controls the engine of the vehicle 1. When it is necessary to accelerate or decelerate the vehicle 1, the ECU 10 transmits a control signal to the engine control system 31 in order to change the engine output.

The brake control system 32 controls the brake device of the vehicle 1. When it is necessary to decelerate the vehicle 1, the ECU 10 transmits a control signal to the brake control system 32 in order to generate a braking force.

The steering control system 33 controls the steering device of the vehicle 1. When it is necessary to change the traveling direction of the vehicle 1, the ECU 10 transmits a control signal to the steering control system 33 to change the steering direction.

Next, the calculation for setting the sampling point SP will be described with reference to FIGS. 3 and 4. 3 and 4 are explanatory views of the route candidate RC and the sampling point SP.

As described above, the ECU 10 sets a plurality of sampling points SP along each route candidate RC. As the number of sampling points SP to be set increases, the evaluation accuracy of the route cost of each route candidate RC increases, but the calculation load increases and the practicality is impaired. Therefore, the ECU 10 sets the sampling point SP based on the warning region WA in order to achieve both the evaluation accuracy of the route cost and the reduction of the calculation load. Hereinafter, a method of setting the sampling point SP will be described.

FIG. 3 shows a route candidate RC and a sampling point SP when the vehicle 1 is traveling in the lane 51a of the traveling path 51. Another vehicle 9, which is an obstacle, is stopped in the lane 51b adjacent to the lane 51a, and the ECU 10 (see FIG. 1) intends to drive the vehicle 1 so as to pass by the side of the other vehicle 9. are doing. A blind spot DA that cannot be seen by the occupants of the vehicle 1 is formed in the traveling direction of the vehicle 1 as compared with the other vehicle 9.

By the route search using the state lattice method described above, route candidates RC _{1 to} RC ₅ are set in the traveling path 51.

The ECU 10 sets a warning area WA ₁ on the traveling path 5. The caution area WA ₁ is a virtual area located in the traveling direction of the vehicle 1 more than the other vehicle 9 and including substantially the entire blind spot DA. Specifically, the warning area WA ₁ extends from the left end 51c of the traveling path 51 to the right end 51d side, and the length in the x direction (see FIG. 2) is L ₂ (for example, 10 m) and the length in the y direction (see FIG. 2). Presents a rectangle of W ₁ (for example, 15 m). The ECU 10 sets the lengths L ₂ and W ₁ larger as the moving speed of the vehicle 1 increases. In the example shown in FIG. 3, the alert area WA ₁ includes a part of each of the route candidates RC _{1 to} RC ₅ .

The ECU 10 sets a sampling point SP at an interval d ₁ along a portion of each of the route candidates RC _{1 to} RC ₄ in the vicinity of the vehicle 1. The interval d ₁ is an example of the first interval according to the present invention. Specifically, the ECU 10 sets the sampling point SP at an interval d ₁ along the first portion RC ₁₁ , RC ₂₁ , RC ₃₁ , RC ₄₁ of the route candidates RC _{1 to} RC ₄ . The first part RC ₁₁ , RC ₂₁ , RC ₃₁ , RC ₄₁ extends from the vehicle 1 in the x direction by a length L ₁ (for example, 10 m). The ECU 10 sets the length L ₁ larger as the moving speed of the vehicle 1 increases.

Further, the ECU 10 sets a sampling point SP at an interval d ₁ along a part of each of the route candidates RC _{1 to} RC ₄ which are relatively close to the blind spot DA. Specifically, the ECU 10 sets a sampling point SP at an interval d ₁ along the second portions RC ₁₂ , RC ₂₂ , RC ₃₂ , and RC ₄₂ included in the caution area WA ₁ among the route candidates RC _{1 to} RC _4. Set.

Further, the ECU 10 includes both the first part RC ₁₁ , RC ₂₁ , RC ₃₁ , RC ₄₁ , and the second part RC ₁₂ , RC ₂₂ , RC ₃₂ , RC ₄₂ among the route candidates RC _{1 to} RC _4. The sampling point SP is set at the interval d ₂ along the excluded portion. The interval d ₂ is an example of the second interval according to the present invention.

The interval d ₂ is larger than the interval d ₁ (for example, d ₁ = 0.2 m, d ₂ = 2.0 m). Therefore, sampling points SP are set at a relatively high density along the first part RC ₁₁ , RC ₂₁ , RC ₃₁ , RC ₄₁ and the second part RC ₁₂ , RC ₂₂ , RC ₃₂ , RC ₄₂ , and other parts. The sampling point SP is set at a relatively low density along the line. In other words, the number of sampling point SPs per unit length in the first part RC ₁₁ , RC ₂₁ , RC ₃₁ , RC ₄₁ and the second part RC ₁₂ , RC ₂₂ , RC ₃₂ , RC ₄₂ is in the other parts. More than that. In addition, among the route candidates RC _{1 to} RC ₄ , in the portion excluding the second portion RC ₁₂ , RC ₂₂ , RC ₃₂ , and RC ₄₂ , the sampling point is separated from the vehicle 1 in the traveling direction of the vehicle 1. The interval for setting SP increases from d ₁ to d ₂ .

On the other hand, regarding the sampling point SP along the route candidate RC ₅ which is not included in the warning area WA ₁ , the ECU 10 sets the interval d ₁ in the first portion RC ₅₁ extending by the length L ₁ in the x direction from the vehicle 1. , Set the interval d ₂ for other parts.

FIG. 4 shows a route candidate RC and a sampling point SP when the vehicle 1 is traveling in the lane 52a of the traveling path 52. A pedestrian crossing zone 52b is provided on the traveling path 52 in the traveling direction of the vehicle 1, and the ECU 10 (see FIG. 1) intends to drive the vehicle 1 so as to intersect the pedestrian crossing zone 52b. ing.

The ECU 10 sets a warning area WA ₂ on the traveling path 5. The alert area WA ₂ is a virtual area set to overlap the pedestrian crossing zone 52b in top view. Specifically, the warning area WA ₂ extends from the left end 52c of the traveling path 52 to the right end 52d side, and the length in the x direction (see FIG. 2) is L ₃ (for example, 10 m) and the length in the y direction (see FIG. 2). Presents a rectangle of W ₂ (for example, 15 m). The ECU 10 sets the lengths L ₃ and W ₂ larger as the moving speed of the vehicle 1 increases. In the example shown in FIG. 4, the alert area WA ₂ includes a part of each of the route candidates RC _{6 to} RC ₉ .

The ECU 10 has sampling points at intervals d ₁ along the first part RC ₆₁ , RC ₇₁ , RC ₈₁ , RC ₉₁ and the second part RC ₆₂ , RC ₇₂ , RC ₈₂ , RC ₉₂ of the route candidates RC _{6 to} RC ₉ . Set the SP. The first part RC ₆₁ , RC ₇₁ , RC ₈₁ , RC ₉₁ is a part extending from the vehicle 1 by the length L ₁ in the x direction, and the second part RC ₆₂ , RC ₇₂ , RC ₈₂ , RC ₉₂ is a caution area. This is the part included in WA ₂ .

On the other hand, regarding the sampling point SP along the route candidate RC ₁₀ , the ECU 10 sets the first portion RC ₁₀₁ extending by the length L ₁ in the x direction from the vehicle 1 with an interval d ₁ , and the other portions have an interval d. Set in ₂ .

As can be understood from FIGS. 3 and 4, the ECU 10 preferentially sets the sampling point SP in the range including the blind spot DA and the pedestrian crossing zone 52b and in the vicinity of the vehicle 1. In other words, the ECU 10 thins out the sampling points SP in the portion of the route candidate RC excluding both the range including the blind spot DA and the pedestrian crossing zone 52b and the portion near the vehicle 1. As a result, it is possible to reduce the calculation load of the route cost in other parts while increasing the evaluation accuracy of the route cost in the range including the blind spot DA and the pedestrian crossing zone 52b and in the vicinity of the vehicle 1. That is, it is possible to achieve both reduction of the calculation load and evaluation accuracy of the route cost.

Next, with reference to FIG. 5, the calculation executed when the ECU 10 provides the driving support control will be described. FIG. 5 is a flowchart showing an operation executed by the ECU 10. The ECU 10 repeatedly executes the calculation shown in FIG. 5 (for example, every 0.05 to 0.2 seconds).

First, in step S1, the ECU 10 acquires travel path information from the camera 21, the radar 22, and the navigation system 30 (see FIG. 1).

Next, in step S2, the ECU 10 specifies the shape of the travel path (for example, the direction in which the travel path extends, the width of the travel path, etc.) based on the travel path information, and a plurality of grid points G _n on the travel path. (N = 1, 2, ... N) is set. The ECU 10 sets grid points G _n every 10 m in the x direction (see FIG. 2) and every 0.875 m in the y direction (see FIG. 2), for example.

Next, in step S3, the ECU 10 acquires obstacle information from the camera 21 and the radar 22. That is, the ECU 10 acquires information on the presence / absence of obstacles on the traveling path in the traveling direction of the vehicle 1, the type of obstacles, the moving direction of the obstacles, the moving speed, and the like.

Next, in step S4, the ECU 10 sets a plurality of route candidate RCs on the traveling path. Specifically, the ECU 10 defines curves extending from the start point P _s (see FIG. 2), which is the position of the vehicle 1 at the time of executing the calculation, to each grid point G _n set in step S2, and routes these curves. Set as a candidate RC.

Next, in step S5, the ECU 10 determines whether or not there is a warning object in the traveling direction of the vehicle 1. The "warning object" means an object to be watched when the vehicle 1 is driven, such as an obstacle on the traveling path or a pedestrian crossing zone. When it is determined that the warning object exists in the traveling direction of the vehicle 1 (S5: YES), the ECU 10 proceeds to step S6.

Next, in step S6, the ECU 10 sets a warning area WA on the traveling path 5. As described above, when the warning target is an obstacle, the ECU 10 sets the warning region WA at a position in the traveling direction of the vehicle 1 with respect to the obstacle. Further, when the object to be watched is a pedestrian crossing zone, the ECU 10 sets the warning area WA so as to overlap with the pedestrian crossing zone in a top view. Further, the ECU 10 increases the outer shape of the warning area WA as the moving speed of the vehicle 1 increases.

When the object to be watched is a vehicle, the ECU 10 may increase the outer shape of the warning area WA according to the type (large vehicle, passenger vehicle, etc.). For example, in the ECU 10, when the warning target is a large vehicle such as a freight vehicle or a bus, the outer shape of the warning region WA may be larger than that when the warning target is a passenger vehicle. The ECU 10 sets the warning area WA in step S6, and then proceeds to step S7.

On the other hand, if it is determined in step S5 that there is no warning object in the traveling direction of the vehicle 1 (S5: NO), the ECU 10 proceeds to step S7 without going through this step S6. That is, the ECU 10 proceeds to step S7 without setting the warning area WA.

Step S7 includes setting the sampling point SP (steps S7a to 7d) and calculating the route cost (step S7e).

In step 7a, the ECU 10 sets the sampling point SP at the interval d ₁ along the portion of the route candidate RC near the vehicle 1. Here, the sampling point SP is set along the portion of the route candidate RC extending from the vehicle 1 in the x direction (see FIG. 2) by a length L ₁ (see FIGS. 3 and 4).

Next, in step S7b, the ECU 10 determines whether or not the route candidate RC is included in the warning area WA. When it is determined that the route candidate RC is included in the caution area WA (S7b: YES), the ECU 10 proceeds to step S7c.

Next, in step S7c, the ECU 10 sets the sampling point SP at the interval d ₁ along the portion of the route candidate RC included in the caution area WA.

Next, in step S7d, the ECU 10 moves the interval d along the other part of the route candidate RC (that is, the part excluding both the part included in the warning area WA and the part in the vicinity of the vehicle 1). Set the sampling point SP at ₂ .

On the other hand, when it is determined in step S7b that the route candidate RC is not included in the warning area WA (S7b: NO), the ECU 10 proceeds to step S7d without going through step S7c. Further, even when the ECU 10 determines in step S5 described above that there is no warning object in the traveling direction of the vehicle 1 (S5: NO) and the warning area WA is not set, the route candidate RC is the warning area in the ECU 10. It is determined that it is not included in WA (S7b: NO), and the process proceeds to step S7d without going through step S7c.

When the route candidate RC is not included in the warning region WA (S7b: NO), the ECU 10 in step S7d along the other part of the route candidate RC (that is, the part excluding the portion near the vehicle 1). , The sampling point SP is set at the interval d ₂ . At this time, the range in which the sampling point SP is set at the interval d ₂ is larger than that in the case where the route candidate RC is included in the warning region WA (S7b: YES). That is, when the route candidate RC is not included in the warning area WA, the number of sampling points SP to be set is smaller than that when the route candidate RC is included in the warning area WA.

Next, in step S7e, the ECU 10 calculates the route cost at each sampling point SP of the route candidate RC. The route cost includes costs related to speed, acceleration, lateral acceleration, path change rate, obstacles, and the like. These costs can be set as appropriate. In general, route costs include travel costs and safety costs. For example, when traveling on a straight route, the travel cost is low because the travel distance is short, but when traveling on a route that avoids obstacles and the like, the travel distance is long and the travel cost is high. In addition, the movement cost increases as the lateral acceleration increases. As described above, the ECU 10 stores the value obtained by division in a memory (not shown) as the route cost of the route candidate RC.

The ECU 10 executes such an operation in step S7 for all of the plurality of route candidate RCs set in step S4.

Next, in step S8, the ECU 10 sets a target path. Specifically, the ECU 10 selects the route candidate RC having the minimum route cost, and sets the route candidate RC as the target route.

Next, in step S9, the ECU 10 transmits a control signal to the engine control system 31, the brake control system 32, and the steering control system 33 so that the vehicle 1 travels along the target route. The control signal is generated based on the control amount of the speed control and steering control of the vehicle 1 set at each sampling point SP of the target route.

Hereinafter, the operation of the vehicle driving support system 100 of the present embodiment will be described.

According to this configuration, the ECU 10 which is a control device sets the sampling point SP at the interval d ₁ along the portion included in the warning area WA in the route candidate RC. The warning area WA is set so as to extend from one end in the width direction of the traveling path to the other end in the width direction. Since the interval d ₁ is smaller than the interval d ₂ , a plurality of sampling points SP are set in the alert area WA at a relatively high density. Therefore, if the warning area WA is set in the vicinity of the target to be watched when the vehicle 1 is driven, it is possible to improve the evaluation accuracy of the route cost in the vicinity of the target.

Further, when controlling the braking system or steering system of the vehicle 1 at each sampling point SP, by setting a plurality of sampling point SPs at a relatively high density in the vicinity of the object to be watched, the vehicle is located in the vicinity of the object. Even when it becomes necessary to stop the vehicle 1, the vehicle 1 can be stopped smoothly and the discomfort given to the driver can be reduced.

On the other hand, for the other part of the route candidate RC (that is, the part not included in the warning area WA), the ECU 10 sets the sampling point SP at the interval d ₂ along the other part. Since the interval d ₂ is larger than the interval d ₁ , a plurality of sampling points SP are set in the other portion at a relatively low density. As a result, it becomes possible to reduce the calculation load of the route cost in the other part. Since the density of the sampling point SP is relatively low, the evaluation accuracy of the route cost in the other portion is also low, but the influence of the evaluation accuracy on the running of the vehicle 1 in the caution area WA is relatively small.

That is, according to the above configuration, it is possible to make the evaluation accuracy of the route cost practically sufficient while reducing the calculation load. As a result, it becomes possible to achieve both the evaluation accuracy of the route cost of the route candidate RC and the reduction of the calculation load thereof.

In addition, the vehicle driving support system 100 includes a camera 21 and a radar 22 that acquire obstacle information regarding obstacles on the traveling path. The ECU 10 is configured to set the warning area WA at a position in the traveling direction of the vehicle 1 with respect to the obstacle.
According to this configuration, it is possible to set a warning zone WA in a blind spot formed by an obstacle (for example, a stopped vehicle on a traveling road, a pedestrian, a wall, a roadside tree, etc.). That is, a plurality of sampling points SP are set in the blind spot at a relatively high density. As a result, it is possible to calculate the route cost of the route candidate RC in consideration of the pedestrians and the like jumping out from the blind spot while reducing the calculation load.

Further, the ECU 10 is configured so that the larger the outer shape of the obstacle, the larger the outer shape of the warning area WA.
The larger the outer shape of the obstacle, the larger the blind spot formed by the obstacle tends to be. According to the above configuration, the larger the outer shape of the obstacle, the larger the outer shape of the warning area WA, so that the portion of the route candidate RC included in the warning area WA becomes larger. That is, the sampling point SP is set at a relatively high density in a range including a large blind spot. As a result, when a pedestrian or the like jumps out from the blind spot, it is possible to calculate the route cost of the route candidate RC in consideration of this jumping out.

Further, the ECU 10 is configured to increase the outer shape of the warning area WA according to the type of obstacle.
For example, when the obstacle is a large vehicle such as a freight vehicle or a bus, the blind spot formed by the obstacle tends to be larger than that when the obstacle is a passenger vehicle. According to the above configuration, it is possible to increase the portion of the route candidate RC in which the sampling point SP is set at the interval d ₁ according to the blind spots that are different for each type of obstacle. As a result, when a pedestrian or the like jumps out from the blind spot, it is possible to calculate the route cost of the route candidate RC in consideration of this jumping out.

Further, the ECU 10 is configured to set a warning area WA that overlaps with the pedestrian crossing zone on the traveling path.
According to this configuration, in a pedestrian crossing zone where there is a relatively high possibility that a pedestrian or the like will jump out, it is possible to calculate the route cost of the route candidate RC in consideration of this jumping out.

Further, the ECU 10 is configured so that the outer shape of the warning area WA becomes larger as the moving speed of the vehicle 1 increases.
The higher the moving speed of the vehicle 1, the more attention must be paid to the jumping out of pedestrians and the like. According to the above configuration, the ECU 10 increases the outer shape of the warning area WA as the moving speed of the vehicle 1 increases, so that the portion of the route candidate RC included in the warning area WA becomes larger. That is, the portion of the route candidate RC in which the sampling point SP is set at the interval d ₁ becomes large. As a result, when a pedestrian or the like jumps out from the blind spot, it is possible to calculate the route cost of the route candidate RC in consideration of this jumping out.

The embodiments of the present invention have been described above with reference to specific examples. However, the present invention is not limited to these specific examples. That is, those skilled in the art with appropriate design changes to these specific examples are also included in the scope of the present invention as long as they have the features of the present invention.

1 Vehicle 10 ECU (control unit)
21 Camera (roadway information acquisition device, obstacle information acquisition device)
22 Radar (roadway information acquisition device, obstacle information acquisition device)
30 Navigation system (roadway information acquisition device)
100 Vehicle driving support system RC route candidate SP sampling point

Claims (6)

It is a vehicle driving support system installed in a vehicle.
A track information acquisition device that acquires track information related to the track,
A control device for setting a target route on the travel path based on the travel path information and controlling the vehicle so as to travel along the target route is provided.
The control device
Based on the travel route information, a plurality of route candidates are set on the travel route, and
A plurality of sampling points are set at predetermined intervals along each of the plurality of route candidates.
The path cost at each of the plurality of sampling points is calculated.
It is configured to select one route candidate from the plurality of route candidates as the target route based on the route cost.
Further, the control device is
A warning area extending from one end in the width direction to the other end in the width direction of the traveling path is set.
Among the route candidates, the sampling points are set at the first interval along the portion included in the caution area, and the sampling points are set at the second interval larger than the first interval along the other portions. Is configured to
A vehicle driving support system characterized by this. Equipped with an obstacle information acquisition device that acquires obstacle information related to obstacles on the road
The vehicle driving support system according to claim 1, wherein the control device is configured to set the warning area at a position in the traveling direction of the vehicle with respect to the obstacle. The vehicle driving support system according to claim 2, wherein the control device is configured so that the larger the outer shape of the obstacle, the larger the outer shape of the warning area. The vehicle driving support system according to claim 3, wherein the control device is configured to increase the outer shape of the warning area according to the type of the obstacle. The vehicle driving support system according to claim 1, wherein the control device is configured to set the warning area that overlaps with the pedestrian crossing zone on the travel path. The vehicle driving support system according to any one of claims 1 to 5, wherein the control device is configured to increase the outer shape of the warning area as the moving speed of the vehicle increases.

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