JP7209946B2 - Vehicle driving support system - Google Patents

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 vehicle route candidates (that is, candidates that can be the target route for actually driving the vehicle). ing. A vehicle driving support system using such an algorithm has also been proposed.

According to the algorithm described above, it is possible to set a plurality of route candidates for the travel route 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 judged appropriate based on the calculation result is selected as the target route. For example, Patent Literature 1 discloses a vehicle driving support system that sets a plurality of route candidates on a grid map and selects one route candidate based on travel costs.

WO2013/051081

The system described in Patent Literature 1 calculates movement costs in all cells through which route candidates pass among a plurality of cells in a grid map. Such a method of calculating route costs at a large number of positions on a route candidate is significant from the viewpoint of improving the evaluation accuracy of the route cost of the route candidate, but entails a large computational load.

In particular, when using a method such as the state lattice method that can set a large number of route candidates, the route cost calculation load may become enormous. For this reason, it has been desired to achieve both a reduction in the computational load and an evaluation accuracy of the route cost.

SUMMARY OF THE INVENTION The present invention has been made to solve such problems, and it is an object of the present invention to provide a vehicle driving support system capable of achieving both the accuracy of route cost evaluation of route candidates and the reduction of the calculation load. do.

In order to solve the above problems, the present invention provides a vehicle driving support system mounted on a vehicle, comprising: a travel road information acquisition device for acquiring travel road information relating to a travel road; a control device that sets a target route and controls the vehicle to travel along the target route; the control device sets a plurality of route candidates on the travel route based on the travel route information; A plurality of sampling points are set at predetermined intervals along each route candidate, the route cost at each of the plurality of sampling points is calculated, and one route candidate is selected from the plurality of route candidates 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 of the travel path to the other end in the width direction, and sets a first interval along a portion of the candidate route included in the warning area. Sampling points are set at , sampling points are set at a second interval larger than the first interval along other parts, and the outline of the warning area is made larger as the moving speed of the vehicle increases . , is characterized.

According to this configuration, the control device sets the sampling points at the first intervals along the part of the route candidate that is included in the caution area. The caution area is set to extend from one end in the width direction of the travel 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 at a relatively high density in the caution area. Therefore, if a warning area is set in the vicinity of an object to be warned of when the vehicle travels, it is possible to improve the accuracy of route cost evaluation in the vicinity of the object.

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

That is, according to the above configuration, it is possible to reduce the computational load and make the route cost evaluation accuracy practically sufficient. As a result, it is possible to achieve both the accuracy of route cost evaluation of route candidates and the reduction of the calculation load.
Also, the higher the moving speed of the vehicle, the more attention must be paid to pedestrians and the like. According to the above configuration, the control device enlarges the outer shape of the caution area as the moving speed of the vehicle increases. That is, the portion of the route candidates for which the sampling points are set at the first interval becomes large. As a result, when a pedestrian or the like jumps out of a blind spot, it becomes possible to calculate the route cost of the route candidate by surely considering this jumping out.

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

In the present invention, preferably, the control device is configured to increase the outline of the caution area as the outline of the obstacle becomes larger.
The larger the outline of an obstacle, the larger the blind spot formed by the obstacle. According to the above configuration, the control device enlarges the outline of the caution area as the outline of the obstacle becomes larger, so that the part of the route candidate that is included in the caution area becomes larger. That is, sampling points are set at a relatively high density in a range including large blind spots. As a result, when a pedestrian or the like jumps out of a blind spot, it becomes possible to calculate the route cost of the route candidate by surely considering this jumping out.

It should be noted that the outline of the caution area does not have to continuously increase as the outline of the obstacle increases. For example, the scope of the present invention includes a form in which the contour of the warning area increases stepwise as the contour of the obstacle increases.

In the present invention, preferably, the control device is configured to increase the outline of the caution area according to the type of obstacle.
For example, when the obstacle is a large vehicle such as a truck or a bus, the blind spot formed by the obstacle tends to be larger than when the obstacle is a passenger car. According to the above configuration, it is possible to increase the portion of the route candidate for which the sampling points are set at the first interval in accordance with the blind spots that differ for each type of obstacle. As a result, when a pedestrian or the like jumps out of a blind spot, it becomes possible to calculate the route cost of the route candidate by surely considering 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 travel road.
According to this configuration, it is possible to calculate the route cost of a route candidate in a pedestrian crossing where the probability of a pedestrian or the like running out is relatively high, taking into account the running out of the pedestrian crossing.

It should be noted that the outline of the caution area does not need to increase continuously with the moving speed of the vehicle. For example, the scope of the present invention also includes a configuration in which the outline of the warning area increases stepwise with the moving speed of the vehicle.

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

1 is a configuration diagram of a vehicle driving support system according to an embodiment; FIG. FIG. 4 is an explanatory diagram of route candidates and sampling points; FIG. 4 is an explanatory diagram of route candidates and sampling points; FIG. 4 is an explanatory diagram of route candidates and sampling points; FIG. 2 is a flow chart showing calculations executed by an ECU in FIG. 1; FIG.

Embodiments will be described below with reference to the accompanying drawings. In order to facilitate understanding of the description, the same components are denoted by the same reference numerals in each drawing, and overlapping descriptions are omitted.

First, an overview of a vehicle driving support system 100 according to the present invention will be described with reference to FIGS. 1 and 2. FIG. FIG. 1 is a configuration diagram of a vehicle driving support system 100. As shown in FIG. FIG. 2 is an explanatory diagram of route candidates RC and sampling points SP.

A vehicle driving support system 100 is mounted on a vehicle 1 and provides driving support control for causing the vehicle 1 to travel along a target route. As shown in FIG. 1, a 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 the driving operation by the occupant, an acceleration sensor 24, a yaw rate sensor 25, a steering angle sensor 26, an accelerator sensor 27, a brake A sensor 28 is included. Furthermore, the multiple sensors include a positioning system 29 for detecting the position of the vehicle 1 and a navigation system 30 . The multiple control systems include an engine control system 31 , a brake control system 32 and a steering control system 33 .

In addition, as other sensors, a peripheral sonar for measuring the distance and position of peripheral structures with respect to the vehicle 1, a corner radar for measuring the approach of peripheral structures at four corners of the vehicle 1, and a vehicle interior of the vehicle 1 may include an inner camera that captures the

The ECU 10 is an example of a control device according to the invention. The ECU 10 is configured by a computer having a CPU, a memory for storing various programs, an input/output device, and the like. The ECU 10 performs various calculations based on signals received from a plurality of sensors, and appropriately controls the engine system, brake system, and steering system for the engine control system 31, brake control system 32, and steering control system 33, respectively. send a control signal to activate the

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

FIG. 2 shows the vehicle 1 running on the road 5. As shown in FIG. The ECU 10 sets a plurality of virtual grid points G _n (n=1, 2, . . . N) on the traveling road 5 existing in the traveling direction of the vehicle 1 by calculation based on the traveling road 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 along the x direction and the y direction.

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

Since the running 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 _Gn are arranged along the direction in which the road extends, if the road includes a curved section, the grid points _Gn are arranged along the curve of the curved section.

Further, the ECU 10 performs 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 traveling road information and the obstacle information. The obstacle information includes the presence or absence of obstacles (e.g., preceding vehicles, parked vehicles, pedestrians, fallen objects, etc.) on the travel path 5 in the traveling direction of the vehicle 1, their types, sizes, moving directions, moving speeds, 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 candidates RC by route search using the state lattice method. According to the state lattice method, a plurality of route candidates RC branching from the starting point P _s toward each grid point G _n existing in the traveling direction of the vehicle 1 are set. The starting point P _s is the position of the vehicle 1 when the calculation is executed. In the example shown in FIG. 2, the vehicle 1 is located at the origin of the xy coordinates, so the coordinates of the starting 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 on the x-y coordinates based on the multi-order function as a route candidate RC. The multi-order 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 part of a plurality of route candidates RC set by the ECU 10 .

Also, the ECU 10 selects one route candidate RC with the lowest route cost from the plurality of route candidates RC. 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 spaced apart from each other on each route candidate RC. FIG. 2 shows, as an example, sampling points SP set at regular intervals along the entire route candidates RC _a , RC _b , and RC _c .

Next, the ECU 10 calculates path costs at each sampling point SP. Furthermore, for each route candidate RC, the ECU 10 sums the route costs at the sampling points SP set along the route candidate RC, and divides the sum by the total length of the route candidate RC. The ECU 10 sets the value obtained by the division as the route cost of the route candidate RC. The ECU 10 selects the route candidate RC with the lowest route cost from among the plurality of route candidates RC, and sets it as the target route.

In addition, the ECU 10 sets control amounts for speed control and steering control of the vehicle 1 at each sampling point. The control amount is set based on the speed and steering required for the vehicle 1 to travel along the target route, and is also used to calculate the route cost. The ECU 10 transmits control signals to the engine control system 31, the brake control system 32, and the steering control system 33 based on the control amounts.

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 detects objects (e.g., preceding vehicles, parked vehicles, pedestrians, roads, lane markings (lane boundaries, white lines, yellow lines), traffic lights, traffic signs, stop lines, intersections, etc.). Further, when the target object is a vehicle, the ECU 10 identifies the type (large vehicle, passenger car, etc.). It should be noted that the ECU 10 may acquire information on the object from the outside through traffic infrastructure, vehicle-to-vehicle communication, or the like. As a result, the type, relative position, movement 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 positions and velocities of objects (particularly preceding vehicles, parked vehicles, pedestrians, fallen objects on the travel 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 reflected waves generated when the transmitted waves are reflected by an 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 addition, 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. Also, a plurality of sensors may be used to configure the position and speed measuring device.

A 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 longitudinal direction, lateral acceleration/deceleration in the lateral direction). A 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 depression amount of the accelerator pedal. A 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 map information inside and can provide the map information to the ECU 10 . Based on the map information and the current vehicle position information, the ECU 10 identifies roads, intersections, traffic lights, buildings, etc. existing around the vehicle 1 (especially in the traveling direction). Map information may be stored in the ECU 10 .

The engine control system 31 controls the engine of the vehicle 1 . The ECU 10 sends a control signal to the engine control system 31 to change the engine output when the vehicle 1 needs to be accelerated or decelerated.

The brake control system 32 controls the braking device of the vehicle 1 . When the vehicle 1 needs to be decelerated, the ECU 10 sends a control signal to the brake control system 32 to generate braking force.

The steering control system 33 controls the steering device of the vehicle 1 . When the traveling direction of the vehicle 1 needs to be changed, the ECU 10 transmits a control signal to the steering control system 33 to change the steering direction.

Next, calculations for setting the sampling points SP will be described with reference to FIGS. 3 and 4. FIG. 3 and 4 are explanatory diagrams of route candidates RC and sampling points 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 accuracy of evaluating the route cost of each route candidate RC increases, but the calculation load increases, impairing practicality. Therefore, the ECU 10 sets the sampling points SP based on the warning area WA in order to achieve both the accuracy of the route cost evaluation and the reduction of the calculation load. A method of setting the sampling points SP will be described below.

FIG. 3 shows route candidates RC and sampling points SP when the vehicle 1 is traveling on the lane 51a of the travel road 51. As shown in FIG. Another vehicle 9, which is an obstacle, is stopped in a lane 51b adjacent to the lane 51a, and the ECU 10 (see FIG. 1) intends to make the vehicle 1 travel so as to pass by the side of the other vehicle 9. are doing. A blind spot DA is formed in the traveling direction of the vehicle 1 relative to the other vehicle 9 so that the occupant of the vehicle 1 cannot see it.

Route candidates RC ₁ to RC ₅ are set on the traveling road 51 by the route search using the state lattice method described above.

The ECU 10 sets a warning area WA ₁ on the travel path 5 . The caution area WA ₁ is a virtual area located in the traveling direction of the vehicle 1 relative to 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 travel path 51 to the right end 51d side, and has a length of L ₂ (for example, 10 m) in the x direction (see FIG. 2) and a length of 10 m in the y direction (see FIG. 2). presents a rectangle of W ₁ (eg, 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 caution area WA ₁ includes a portion of each of the route candidates RC ₁ -RC ₅ .

The ECU 10 sets sampling points SP at intervals of d ₁ along portions near the vehicle 1 among the route candidates RC ₁ to RC ₄ . The interval d1 is an example of the _first interval according to the invention. Specifically, the ECU 10 sets sampling points SP at intervals d ₁ along the first portions RC ₁₁ , RC ₂₁ , RC ₃₁ and RC ₄₁ of the route candidates RC ₁ to RC ₄ . The first portions RC ₁₁ , RC ₂₁ , RC ₃₁ , RC ₄₁ extend from the vehicle 1 in the x-direction by a length L ₁ (eg, 10 m). The ECU 10 sets the length L ₁ larger as the moving speed of the vehicle 1 increases.

In addition, the ECU 10 sets sampling points SP at intervals d ₁ along portions of each of the route candidates RC ₁ to RC ₄ relatively close to the blind spot DA. Specifically, the ECU 10 selects the sampling points SP at intervals d ₁ along the second portions RC ₁₂ , RC ₂₂ , RC ₃₂ , RC ₄₂ included in the warning area WA ₁ of the route candidates RC ₁ to RC ₄ . set.

Further, the ECU 10 selects both the first portions RC ₁₁ , RC ₂₁ , RC ₃₁ and RC ₄₁ and the second portions RC ₁₂ , RC ₂₂ , RC ₃₂ and RC ₄₂ of the route candidates RC ₁ to RC ₄ . Sampling points SP are set at intervals of d ₂ along the removed portion. The interval d2 is an example of the _second interval according to the invention.

Spacing d ₂ is greater than spacing d ₁ (eg, d ₁ =0.2 m, d ₂ =2.0 m). Therefore, the sampling points SP are set at a relatively high density along the first portions _RC11 , _RC21 , _RC31 , _RC41 and the second portions _RC12 , _RC22 , _RC32 , _RC42 , and the other portions Sampling points SP are set at a relatively low density along the . _In other words, the number of sampling points SP per unit length in the first portions _RC11 , RC21, _RC31 , _RC41 and the second portions _RC12 , _RC22 , _RC32 , _RC42 is the same as in the other portions. more than that. Further, in the portions of the route candidates RC ₁ to RC ₄ excluding the second portions RC ₁₂ , RC ₂₂ , RC ₃₂ and RC ₄₂ , sampling points _The interval for setting the SP increases from _d1 to d2.

On the other hand, regarding the sampling points SP along the route candidate RC ₅ not included in the warning area WA ₁ , the ECU 10 sets the first portion RC ₅₁ extending in the x direction from the vehicle 1 by the length L ₁ with an interval d ₁ . , and other portions are set at intervals of d ₂ .

FIG. 4 shows route candidates RC and sampling points SP when the vehicle 1 is traveling on the lane 52a of the travel road 52. As shown in FIG. A pedestrian crossing zone 52b is provided on the running path 52 in the traveling direction of the vehicle 1, and the ECU 10 (see FIG. 1) intends to cause the vehicle 1 to travel so as to cross the pedestrian crossing zone 52b. ing.

The ECU 10 _sets a warning area WA2 on the travel path 5. FIG. The caution area _WA2 is a virtual area set so as to overlap with the pedestrian crossing zone 52b when viewed from above. Specifically, the caution area WA ₂ extends from the left end 52c of the travel path 52 to the right end 52d side, and has a length of L ₃ (for example, 10 m) in the x direction (see FIG. 2) and a length of 10 m in the y direction (see FIG. 2). presents a rectangle of W ₂ (eg, 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 caution area WA ₂ includes a portion of each of the route candidates RC ₆ -RC ₉ .

The ECU 10 _selects sampling points at intervals d1 along the _first portions _RC61 , _RC71 , _RC81 , _RC91 and the second portions _RC62 , _RC72 , _RC82 , _RC92 of the route candidates RC6 to _RC9 . Set SP. The first portions RC ₆₁ , RC ₇₁ , RC ₈₁ , RC ₉₁ are portions extending in the x direction from the vehicle 1 by a length L ₁ , and the second portions RC ₆₂ , RC ₇₂ , RC ₈₂ , RC ₉₂ are caution areas. This is the part included in _WA2 .

On the other hand, with respect to the sampling points SP along the route candidate RC ₁₀ , the ECU 10 sets the first portion RC ₁₀₁ extending from the vehicle ₁ by the length L1 in the x direction with the interval d1, and the _other portions with the interval d1. Set with ₂ .

As can be understood from FIGS. 3 and 4, the ECU 10 preferentially sets the sampling points SP in a range including the blind spot DA and the pedestrian crossing zone 52b and in the vicinity of the vehicle 1. FIG. In other words, the ECU 10 thins out the sampling points SP in a portion of the route candidate RC excluding both the range including the blind spot DA and pedestrian crossing 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 areas while increasing the accuracy of the route cost evaluation 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 a reduction in the calculation load and an evaluation accuracy of the route cost.

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

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

Next, in step S2, the ECU 10 identifies the shape of the road (for example, the direction in which the road extends, the width of the road, etc.) based on the road information, and sets a plurality of grid points _Gn on the road. (n=1, 2, . . . N) are set. For example, the ECU 10 sets grid points _Gn at intervals of 10 m in the x direction (see FIG. 2) and at intervals of 0.875 m in the y direction (see FIG. 2).

Next, in step S<b>3 , the ECU 10 acquires obstacle information from the camera 21 and the radar 22 . That is, the ECU 10 acquires information about the presence or absence of obstacles on the traveling road in the traveling direction of the vehicle 1, the types of obstacles, the direction of movement of obstacles, the speed of movement of obstacles, and the like.

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

Next, in step S<b>5 , the ECU 10 determines whether or not there is a warning target in the traveling direction of the vehicle 1 . The "warning object" means an object to be warned of when the vehicle 1 is driven, such as an obstacle on the road or a pedestrian crossing. If it is determined that there is a warning target in the traveling direction of the vehicle 1 (S5: YES), the ECU 10 proceeds to step S6.

Next, in step S<b>6 , the ECU 10 sets a warning area WA on the travel road 5 . As described above, when the object to be warned is an obstacle, the ECU 10 sets the warning area WA at a position in the traveling direction of the vehicle 1 from the obstacle. Further, when the warning target is a pedestrian crossing zone, the ECU 10 sets the warning area WA so as to overlap the pedestrian crossing zone when viewed from above. Further, the ECU 10 enlarges the outline of the warning area WA as the moving speed of the vehicle 1 increases.

If the object to be warned is a vehicle, the ECU 10 may increase the outline of the warning area WA according to its type (large vehicle, passenger car, etc.). For example, when the object to be warned is a large vehicle such as a truck or a bus, the ECU 10 may make the outline of the caution area WA larger than when the object to be warned is a passenger car. After setting the warning area WA in step S6, the ECU 10 proceeds to step S7.

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

Step S7 includes setting of sampling points SP (steps S7a to 7d) and calculation of route costs (step S7e).

At step 7a, the ECU ₁₀ sets sampling points SP at intervals d1 along the portion of the route candidate RC near the vehicle 1. FIG. Here, sampling points SP are set along a portion of the route candidate RC that extends from the vehicle ₁ in the x direction (see FIG. 2) by a length L1 (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 determining that the route candidate RC is included in the warning area WA (S7b: YES), the ECU 10 proceeds to step S7c.

Next, in step S7c, the ECU ₁₀ sets sampling points SP at intervals d1 along the portion of the route candidate RC that is included in the caution area WA.

Next, in step S7d, the ECU 10 extends the distance d ₂ sets the sampling point SP.

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 if the ECU 10 determines in step S5 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 ECU 10 determines that the route candidate RC is in the warning area. It is determined that it is not included in WA (S7b: NO), and the process proceeds to step S7d without going through step S7c.

If the route candidate RC is not included in the caution area WA (S7b: NO), the ECU 10, in step S7d, follows the route candidate RC along the rest of the route candidate RC (that is, the portion excluding the vicinity of the vehicle 1). , set sampling points SP at intervals d ₂ . At this time, the range in which the sampling points SP _are set at the interval d2 is larger than when the route candidate RC is included in the caution area WA (S7b: YES). That is, when the route candidate RC is not included in the caution area WA, the number of sampling points SP to be set is smaller than when the route candidate RC is included in the caution area WA.

Next, in step S7e, the ECU 10 calculates the route cost at each sampling point SP of the route candidate RC. Path costs include costs related to velocity, acceleration, lateral acceleration, path change rate, obstacles, and the like. These costs can be set as appropriate. Generally speaking, path costs include travel costs and safety costs. For example, when traveling on a straight route, the travel distance is short, so the travel cost is small. Also, the movement cost increases as the lateral acceleration increases. As described above, the ECU 10 stores the value obtained by the division in a memory (not shown) as the route cost of the route candidate RC.

The ECU 10 performs the calculation of step S7 for all of the plurality of route candidates RC set in step S4.

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

Next, in step S9, the ECU 10 transmits control signals 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.

The operation of the vehicle driving support system 100 of this embodiment will be described below.

According to this configuration, the ECU 10, which is the controller, _sets the sampling points SP at intervals d1 along the portion of the route candidate RC that is included in the warning area WA. The caution area WA is set to extend from one end in the width direction of the travel 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 at a relatively high density in the caution area WA. Therefore, if the warning area WA is set in the vicinity of an object to be warned of when the vehicle 1 is driven, it is possible to improve the evaluation accuracy of the route cost in the vicinity of the object.

Further, when controlling the braking system and the steering system of the vehicle 1 at each sampling point SP, by setting a plurality of sampling points SP at a relatively high density in the vicinity of the object to be warned, the vehicle can be detected 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, the ECU 10 _sets sampling points SP at intervals d2 along the other portion of the route candidate RC (that is, the portion not included in the caution area WA). Since the interval d2 is larger _than the interval d1, _a plurality of sampling points SP are set at a relatively low density in the other portion. As a result, it becomes possible to reduce the calculation load of the route cost in the other portion. Since the density of the sampling points 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 traveling of the vehicle 1 in the warning area WA is relatively small.

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

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

Further, the ECU 10 is configured to increase the outer shape of the caution area WA as the outer shape of the obstacle is larger.
The larger the outline of an obstacle, the larger the blind spot formed by the obstacle. According to the above configuration, the ECU 10 enlarges the outline of the warning area WA as the outline of the obstacle becomes larger, so that the part of the route candidate RC included in the warning area WA becomes larger. That is, the sampling points SP are set at a relatively high density in a range including large blind spots. As a result, when a pedestrian or the like jumps out of the blind spot, it becomes possible to calculate the route cost of the route candidate RC by surely considering the 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 truck or a bus, the blind spot formed by the obstacle tends to be larger than when the obstacle is a passenger car. According to the above configuration, it is possible to increase the portion of the route candidate RC in which the sampling points SP are set at the interval d ₁ in accordance with the blind spots that differ for each type of obstacle. As a result, when a pedestrian or the like jumps out of the blind spot, it becomes possible to calculate the route cost of the route candidate RC by surely considering the jumping out.

The ECU 10 is also configured to set a warning area WA that overlaps the pedestrian crossing zone on the road.
According to this configuration, it is possible to calculate the route cost of the route candidate RC in a pedestrian crossing where the probability of a pedestrian or the like running out is relatively high, taking into account the running out of the pedestrian crossing.

Further, the ECU 10 is configured to increase the outer shape of the caution area WA as the moving speed of the vehicle 1 increases.
As the moving speed of the vehicle 1 increases, it is necessary to pay more attention to pedestrians and the like. According to the above configuration, the ECU 10 enlarges 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 where the sampling points SP are set at the _interval d1 becomes large. As a result, when a pedestrian or the like jumps out of the blind spot, it becomes possible to calculate the route cost of the route candidate RC by surely considering the jumping out.

The embodiments of the present invention have been described above with reference to specific examples. However, the invention is not limited to these specific examples. In other words, the scope of the present invention includes any design modifications made by those skilled in the art to these specific examples as long as they have the features of the present invention.

1 vehicle 10 ECU (control device)
21 camera (travel path information acquisition device, obstacle information acquisition device)
22 radar (running path information acquisition device, obstacle information acquisition device)
30 navigation system (running route information acquisition device)
100 Vehicle driving support system RC Route candidate SP Sampling point

Claims (5)

A vehicle driving support system mounted on a vehicle,
a traveling road information acquisition device that acquires traveling road information about the traveling road;
a control device that sets a target route on the travel route based on the travel route information and controls the vehicle to travel along the target route;
The control device is
setting a plurality of route candidates on the travel route based on the travel route information;
setting a plurality of sampling points at predetermined intervals along each of the plurality of route candidates;
calculating a path cost at each of the plurality of sampling points;
configured to select one route candidate from the plurality of route candidates as the target route based on the route cost;
Furthermore, the control device
setting a caution area extending from one end in the width direction of the running path to the other end in the width direction;
The sampling points are set at a first interval along a portion of the route candidate included in the caution area, and the sampling points are set at a second interval larger than the first interval along the other portion. ,
It is configured to increase the outer shape of the caution area as the moving speed of the vehicle increases.
A vehicle driving support system characterized by: Equipped with an obstacle information acquisition device that acquires obstacle information about obstacles on the traveling road,
2. The vehicle driving support system according to claim 1, wherein said control device is configured to set said caution area at a position in the traveling direction of said vehicle relative to said obstacle. 3. The vehicle driving support system according to claim 2, wherein said control device is configured to increase the outer shape of said caution area as the outer shape of said obstacle is larger. 4. The vehicle driving support system according to claim 3, wherein said control device is configured to increase the outline of said warning area according to the type of said obstacle. 2. The vehicle driving support system according to claim 1, wherein said control device is configured to set said warning area overlapping a pedestrian crossing zone on said travel road.

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