JP6562387B2 - Vehicle driving support system and method - Google Patents

Description

  The present invention relates to a vehicle driving support system and method, and more particularly, to a vehicle driving support system and method for performing travel route calculation by route search using a plurality of grid points.

  Conventionally, as a vehicle travel route generation algorithm, a potential method, a spline interpolation function, an A star (A *), an RRT, a state lattice method, and the like are known. A vehicle driving support system using such an algorithm has been proposed.

  In the state lattice method, a grid area including a large number of grid points is set on a travel route, and a large number of travel route candidates are set by sequentially connecting the grid points. Then, one travel route is selected from these travel route candidates. For example, Patent Document 1 discloses a vehicle driving support system that calculates a plurality of travel routes on a grid map and selects one travel route based on the calculated travel routes.

International Publication No. 2013/051081 Pamphlet

  The state lattice method is considered to be the most advantageous among the above algorithms in terms of driving route selectivity, vehicle motion diversity, and vehicle behavior fidelity. It is disadvantageous. Therefore, it is conceivable to limit the number of grids in order to reduce the calculation load. However, when the number of grids is uniformly reduced, the number of travel routes selected decreases, and there is a possibility that a travel route suitable for the driving preference of the driver cannot be calculated.

  The present invention has been made to solve such a problem, and a vehicle driving support system and method capable of calculating a driving route suitable for the driving preference of the driver by searching for a route using a plurality of grid points. The purpose is to provide.

In order to achieve the above object, the present invention provides a travel path information acquisition unit that acquires travel path information related to a travel path of a vehicle, and a grid area composed of a plurality of grid points on the travel path based on the travel path information. Based on a predetermined condition from a plurality of travel route candidates, a grid region setting unit to be set, a travel route candidate computation unit that computes a plurality of travel route candidates by route search using a plurality of grid points in the grid region A target driving route calculation unit that selects one driving route candidate as a target driving route, wherein the grid area setting unit is configured to use adjacent grid points based on the driving history information related to the past driving state of the vehicle. it is to set the grid spacing between, on the basis of the running history information, and the vehicle tends to travel a certain widthwise position in the lane of the travel road determining If it, the grid area setting unit is characterized in that the grid spacing in the width direction in the vicinity of a specific position in the width direction is set smaller than the grid interval in the width direction of the width direction position other than the vicinity of a specific position in the width direction .

  According to the present invention configured as described above, the grid area setting unit sets the grid interval based on the travel history information, and the travel route candidate calculation unit uses the grid points set by the grid area setting unit. Travel route candidates can be calculated. Therefore, compared with the conventional case where the grid points of the grid area are set without considering the travel history information, the present invention can calculate a target travel route suitable for the driving preference of the driver.

In addition , when there is a tendency to travel in a specific position in the width direction, it is possible to calculate a travel route candidate more precisely or more precisely at that position by setting the grid interval at that position in the width direction small. It becomes. Thereby, the target travel route suitable for the driving preference of the driver can be calculated.

In the present invention, preferably, based on the travel history information, when it is determined that the vehicle tends to travel to the right side or the left side from the center in the lane of the travel path, the grid area setting unit is offset The grid interval in the width direction on the right side or the left side determined to have a tendency to travel is set smaller than the grid interval in the width direction on the opposite side.
According to the present invention configured as described above, when the vehicle tends to travel on the right side or the left side of the lane, the grid interval at the position in the width direction is set small, so that the position can be more precisely or It becomes possible to calculate the travel route candidate more precisely. Thereby, the target travel route suitable for the driving preference of the driver can be calculated.

In the present invention, preferably, when it is determined, based on the travel history information, that the vehicle has a tendency to travel in the inner area close to the center of the curve in the curve section, the grid area setting unit has a width in the inner area in the curve section. The grid interval in the direction is set smaller than the grid interval in the width direction in the outer region away from the curve center.
According to the present invention configured as described above, when a vehicle tends to travel on a specific route in a curve section, by setting a grid interval near the specific route to be smaller, the vehicle is more It is possible to calculate the travel route candidate precisely or more precisely. Thereby, the target travel route suitable for the driving preference of the driver can be calculated.

In the present invention, preferably, based on the travel history information, when it is determined that the vehicle has a tendency to travel in an outer region away from the curve center in a section before the curve section, the grid region setting unit In the previous section, the grid interval in the width direction in the outer region is set to be smaller than the grid interval in the width direction in the inner region near the center of the curve.
According to the present invention configured as described above, when the vehicle tends to enter the curve section from the out side, by setting the out side grid interval small in the section before the curve section, Thus, it becomes possible to calculate the travel route candidate more precisely or more precisely. Thereby, the target travel route suitable for the driving preference of the driver can be calculated.

In order to achieve the above object, the present invention provides a vehicle driving support method executed by a vehicle control device, a travel path information detecting step for detecting travel path information relating to a travel path of the vehicle, and a travel path. Based on the information, a grid area setting step for setting a grid area composed of a plurality of grid points on the road, and a travel path candidate for calculating a plurality of travel path candidates by a route search using the plurality of grid points in the grid area A calculation step, and a target travel route calculation step for selecting one travel route candidate as a target travel route based on a predetermined condition from a plurality of travel route candidates. based on the running history information relating comprises the step of setting the grid spacing between adjacent grid points, based on the travel history information When it is determined that the vehicle has a tendency to travel in a specific width direction position in the lane of the travel path, the grid area setting step sets the width grid interval in the vicinity of the specific width direction position to the specific width direction. comprising the step of setting smaller than the width direction of the grid spacing in the width direction position other than near position is characterized in Rukoto.

  According to the vehicle driving support system and method of the present invention, a travel route suitable for the driving preference of the driver can be calculated by route search using a plurality of grid points.

1 is a configuration diagram of a vehicle driving support system in an embodiment of the present invention. It is explanatory drawing of the grid area | region in embodiment of this invention. It is explanatory drawing of the grid area | region in which the initial grid point in embodiment of this invention was set. It is explanatory drawing of the grid area | region in which the grid point (Elimination of an unnecessary initial grid point) was set in the embodiment of the present invention. It is explanatory drawing of the target driving | running route in embodiment of this invention. It is a flowchart of the target travel route calculation process in the embodiment of the present invention. It is explanatory drawing of the 3rd process in embodiment of this invention. It is explanatory drawing of the 4th process in embodiment of this invention. It is explanatory drawing of the 5th process in embodiment of this invention. It is explanatory drawing of the 5th process in embodiment of this invention. It is explanatory drawing of the 5th process in embodiment of this invention. It is explanatory drawing of the 5th process in embodiment of this invention. It is explanatory drawing of the 6th process in embodiment of this invention. It is explanatory drawing of the 6th process in embodiment of this invention.

  Hereinafter, a vehicle driving support system according to an embodiment of the present invention will be described with reference to the accompanying drawings. First, the configuration of the vehicle driving support system will be described with reference to FIG. FIG. 1 is a configuration diagram of a vehicle driving support system.

  The vehicle driving support system 100 of the present embodiment is configured to calculate a driving route for the vehicle 1 (see FIG. 2 and the like) and provide driving support control using this driving route. The system 100 calculates a plurality of travel route candidates using the state lattice method, and selects one travel route candidate as a target travel route based on the route cost of each candidate.

  As shown in FIG. 1, a vehicle driving support system 100 mounted on a vehicle 1 includes a vehicle control device (ECU) 10, a plurality of sensors and switches, and a plurality of control systems. The plurality of sensors and switches include an in-vehicle camera 21, a millimeter wave radar 22, a plurality of behavior sensors (vehicle speed sensor 23, acceleration sensor 24, yaw rate sensor 25) for detecting the behavior of the vehicle, and a plurality of behavior switches (steering angle sensor 26). , Accelerator sensor 27, brake sensor 28), positioning system 29, and navigation system 30 are included. The plurality of control systems include an engine control system 31, a brake control system 32, and a steering control system 33.

  Further, as other sensors and switches, a peripheral sonar that measures the distance and position of the peripheral structure relative to the vehicle 1, a corner radar that measures the approach of the peripheral structure at four corners of the vehicle 1, and the interior of the vehicle 1 An inner camera that captures the image may be included. In this case, the ECU 10 receives measurement signals / data from these sensors and switches.

  The ECU 10 includes a computer having a CPU, a memory for storing various programs, an input / output device, and the like. The ECU 10 requests the engine control system 31, the brake control system 32, and the steering control system 33 to appropriately operate the engine system, the brake system, and the steering system, respectively, based on signals received from a plurality of sensors and switches. The signal can be output.

  The ECU 10 functionally includes a travel route information acquisition unit 11, a grid area setting unit 12, a travel route candidate calculation unit 13, a target travel route calculation unit 14, a vehicle control unit 15, and a travel history information storage unit. 16.

  The travel path information acquisition unit 11 acquires various types of information from sensors and switches, and calculates travel path information related to the travel path on which the vehicle 1 travels based on these information. The travel path information includes information regarding the shape of the travel path itself and information regarding objects (including obstacles) on the travel path. The information on the travel road shape includes the travel road shape (straight line, curve, curve curvature), travel road width, number of lanes, lane width, and the like. The information related to the object includes the relative position and relative speed of the object with respect to the vehicle 1, the attribute (type, moving direction) of the object, and the like.

The grid area setting unit 12 sets a virtual grid area (see FIG. 4) on the travel path based on the travel path information. This grid area has a plurality of grid points. Each grid point identifies a position on the road.
The travel route candidate calculation unit 13 calculates a plurality of travel route candidates by route search using a plurality of grid points in the grid area. In this embodiment, the state lattice method is adopted as a route search method. In the state lattice method, a path is branched from a certain grid point to all adjacent grid points in front of the traveling direction of the vehicle 1. Therefore, each traveling route candidate is set so as to pass through a plurality of grid points sequentially. Each travel route candidate includes time information indicating the time passing through each grid point, speed information regarding the speed and acceleration at each grid point, and other information regarding vehicle motion.

The target travel route calculation unit 14 selects one travel route that minimizes the route cost from a plurality of travel route candidates based on a predetermined condition, and sets this as the target travel route.
The vehicle control unit 15 outputs a request signal to the systems 31, 32, 33 so that the vehicle 1 travels on the set target travel route.

  The travel history information storage unit 16 creates travel history information related to past travel states of the vehicle 1 based on various information acquired from the sensors and switches, and stores the travel history information in the memory. The travel history information is created from, for example, a travel state when driving support from the vehicle driving support system 100 is not received.

  The travel history information includes information on the position in the width direction of the lane in which the vehicle 1 actually traveled (for example, the distance in the width direction from the center in the width direction). Therefore, the position in the width direction where the vehicle 1 travels can be specified by the travel history information, particularly in the straight section. For example, it is possible to specify a position having the highest travel time or travel distance ratio in the width direction position in the lane.

  The travel history information also includes the position in the width direction of the lane in which the vehicle 1 travels particularly during the curve section. Therefore, the position in the width direction in which the vehicle 1 travels can be specified in the curve section based on the travel history information. For example, in each travel section such as an entrance section, a central section, and an exit section in a curve section, a position having the highest travel time or travel distance ratio among the width direction positions in the lane can be specified.

  The in-vehicle camera 21 images the surroundings of the vehicle 1 and outputs the captured image data. Based on the image data, the ECU 10 (traveling road information acquisition unit 11) is a target (e.g., vehicle, pedestrian, road, lane line (lane boundary line, white line, yellow line), traffic signal, traffic sign, stop line, Identify intersections, obstacles, etc.) In addition, ECU10 may acquire the information of a target object from the exterior via a vehicle-mounted communication apparatus by traffic infrastructure, vehicle-to-vehicle communication, etc. Thereby, the type, relative position, moving direction, etc. of the object are specified.

  The millimeter wave radar 22 is a measuring device that measures the position and speed of an object (particularly, a preceding vehicle, a parked vehicle, a pedestrian, an obstacle, etc.), and transmits radio waves (transmitted waves) toward the front of the vehicle 1. Then, the reflected wave generated by reflecting the transmission wave by the object is received. The millimeter wave 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 the present embodiment, instead of the millimeter wave radar 22, a distance from the object and a relative speed may be measured using a laser radar, an ultrasonic sensor, or the like. Moreover, you may comprise a position and speed measuring apparatus using a some sensor.

The vehicle speed sensor 23 detects the absolute speed of the vehicle 1.
The acceleration sensor 24 detects the acceleration (vertical acceleration / deceleration in the front-rear direction, lateral acceleration in the horizontal direction) of the vehicle 1.
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 map information therein and can provide the map information to the ECU 10. The ECU 10 (running road information acquisition unit 11) specifies roads, intersections, traffic signals, buildings, and the like existing around the vehicle 1 (particularly in the forward 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 is a controller that controls the engine of the vehicle 1. When it is necessary to accelerate or decelerate the vehicle 1, the ECU 10 outputs an engine output change request signal requesting the engine control system 31 to change the engine output.

  The brake control system 32 is a controller for controlling the brake device of the vehicle 1. When it is necessary to decelerate the vehicle 1, the ECU 10 outputs a brake request signal requesting the brake control system 32 to generate a braking force on the vehicle 1.

  The steering control system 33 is a controller that controls the steering device of the vehicle 1. When it is necessary to change the traveling direction of the vehicle 1, the ECU 10 outputs a steering direction change request signal for requesting the steering control system 33 to change the steering direction.

  Next, the driving support control process according to the present embodiment will be described with reference to FIGS. 2 is an explanatory diagram of the grid area, FIG. 3 is an explanatory diagram of the grid area in which the initial grid points are set, and FIG. 4 is an explanatory diagram of the grid area in which the grid points (unnecessary initial grid points are removed) are set. 5 is an explanatory diagram of the target travel route, and FIG. 6 is a flowchart of the target travel route calculation process.

  2 to 5, the vehicle 1 is traveling on the traveling path 5. At this time, the ECU 10 repeatedly calculates the calculation process of FIG. 6 (for example, every 0.05 to 0.2 seconds). The traveling path 5 has three lanes (lanes 5a, 5b, 5c), and the vehicle 1 is traveling on the lane 5b.

  First, the ECU 10 (running road information acquiring unit 11) acquires various information from a plurality of sensors and switches, and executes an information acquisition process for calculating the driving road information (step S11).

  Next, as shown in FIG. 2, the ECU 10 (grid region setting unit 12) specifies the shape of the travel path 5 (that is, the direction in which the travel path 5 extends, the travel path width, etc.) based on the travel path information. Then, a grid area forming process for virtually forming the grid area 40 on the travel path 5 is executed (step S12).

  The grid area 40 extends from the periphery of the vehicle 1 to the front of the vehicle 1 by a predetermined distance along the traveling path 5. This distance (length in the vertical direction) L is calculated based on the current vehicle speed of the vehicle 1. In the present embodiment, the distance L is a distance expected to travel at a predetermined fixed time t (for example, 3 seconds) at the current vehicle speed (V) (L = V × t). However, the distance L may be a predetermined fixed distance (for example, 100 m) or a function of the vehicle speed (and acceleration). In addition, the width W of the grid area 40 is set to the width of the travel path 5.

  The grid area 40 is divided into a number of rectangular grid sections 42 by a plurality of grid lines 41x and 41y extending along the width direction (lateral direction) X and the extending direction Y of the travel path 5, respectively. In the present embodiment, the number (Nx, Ny) of the grid sections 42 is set to a fixed value in each of the X direction and the Y direction, and the spacing between adjacent grid lines (grid spacing Gx, Gy) is set to be the same ( Gx = W / Nx, Gy = L / Ny). However, the grid intervals Gx and Gy may be set to fixed lengths to change the number of grid sections.

  The grid lines 41x and 41y intersect at a large number of grid intersections 43a. In this embodiment, this grid intersection 43a is used as a grid point for setting the travel route, and the travel route is set so as to pass the grid point. However, the grid section 42 itself may be used as a grid point.

  In FIG. 2, since the traveling path 5 is a straight section, the grid area 40 (and the grid section 42) is set to a rectangular shape. However, the grid line 41y is set along the extending direction of the travel path, and the grid line 41x is set to be orthogonal to the grid line 41y (extend in the width direction of the travel path). For this reason, when the traveling path 5 includes a curve section, the grid area 40 (and the grid section 42) is also set to be curved along the curve section (see FIG. 7). In this case, the grid section 42 is not formed in a rectangular shape but is formed in a fan shape lacking the center side.

  Next, as shown in FIG. 3, the ECU 10 (grid area setting unit 12) executes an initial grid point setting process for setting the initial grid points 43 in the grid area 40 (step S13). In the present embodiment, among the grid intersections 43 a, the grid intersection 43 a located in the Y direction forward from the front end position of the vehicle 1 is set as the initial grid point 43. When an obstacle is detected on the traveling path 5, the initial grid point 43 may not be arranged in the area where the obstacle exists in the initial grid point setting process.

  Then, as shown in FIG. 4, the ECU 10 (grid region setting unit 12) executes a grid point resetting process for resetting the grid points 44 for calculating the travel route candidate based on the initial grid points 43. (Step S14). The grid point resetting process includes a plurality of processes, and details of each process will be described later.

In FIG. 4, grid points 44 (indicated by black circles) are set in different patterns for each of the areas A1 to A4. The grid point 44 is not set in the non-setting areas D _L and D _R. In a substantially elliptical surrounding area A1 extending in front of the vehicle 1, the grid interval between adjacent grid points 44 is set larger than the grid intervals Gx and Gy of the initial grid points 43. This is because the initial grid point 43 between adjacent grid points 44 has been removed.

  Proximal area | region A2 is a cyclic | annular area | region of the external shape substantially ellipse shape set to the outer side of area | region A1. The grid interval in the area A2 is the same as the grid intervals Gx and Gy. Further, the distal region A3 is an annular region having a substantially elliptical outer shape set outside the region A2. The grid interval in the region A3 is set larger than the grid intervals Gx and Gy, similarly to the region A1. The grid points 44 are not set in the distal region A4 outside the region A3 in the grid region 40, or the grid point density is set lower than that in the region A3. As described above, the total number of reset grid points 44 is reduced by the resetting process from the total number of initial grid points 43.

  Next, the ECU 10 (travel route candidate computation unit 13) executes travel route candidate computation processing that computes a plurality of travel route candidates that can be theoretically generated using the grid points 44 (step S15). This process is the same as the calculation of the travel route candidate using the conventional state lattice method. However, in the present embodiment, the calculation is performed using the grid points 44 whose number is reduced from the initial grid points 43. In this respect, the present embodiment is different from the conventional one. In the present embodiment, since the grid points having a reduced number are used, the calculation load is greatly reduced.

  An outline of the travel route candidate calculation process will be described. The ECU 10 starts from a grid point 44 in the vicinity of the vehicle 1. The grid points 44 and a plurality of grid points 44 existing in front of the traveling direction (Y direction) are respectively connected by divided paths, and the connected grid points 44 and a plurality of grid points existing further forward in the traveling direction. 44 are connected to each other through a divided path. Such connection by the divided paths is repeated until the grid point 44 located at the boundary of the front portion of the region A3 (or the front boundary of the region A4 when the grid point 44 exists in the region A4) is reached. As a result, a large number of theoretically possible travel route candidates that sequentially pass from the starting grid point 44 to the forward grid point 44 in the traveling direction and reach the front portion of the area A3 are generated. Then, the ECU 10 calculates the speed, acceleration, steering angle, and the like at each grid point 44 that passes through for each travel route candidate, and calculates request signals for the systems 31, 32, and 33. In this way, a large number of travel route candidates are calculated.

  Next, the ECU 10 (target travel route calculation unit 14) executes target travel route calculation processing for setting one travel route candidate selected from a large number of travel route candidates as the target travel route (step S16). This process includes a route cost calculation process (step S16a) for calculating the route cost of each travel route candidate, a travel route selection process (step S16b) for selecting a travel route candidate with the smallest route cost, and the selected travel route. And a target travel route setting process (step S16c) for setting candidates as target travel routes.

  The route cost includes costs related to speed, acceleration, lateral acceleration, route change rate, obstacles, and the like. These costs can be set as appropriate. In general, the route cost includes a movement cost and a safety cost. For example, when traveling on a straight route, the travel cost is small because the travel distance is short. However, when traveling on a route that avoids an obstacle or the like, the travel distance is long, so the travel cost increases. Further, the movement cost increases as the lateral acceleration increases.

  Further, for example, a route that largely avoids an obstacle can reliably avoid a collision with the obstacle, so the safety cost is reduced. However, a route that passes near the obstacle increases the safety cost. FIG. 5 is an example different from FIGS. 2 to 4, but the target travel route R with the minimum route cost selected when an obstacle 3 (for example, a parked vehicle) is detected on the travel route 5. Is shown.

  Next, the ECU 10 (vehicle control unit 15) executes an operation control process for outputting a request signal so that the vehicle 1 travels on the target travel route (step S17), and ends the process.

  Next, the grid point resetting process according to the present embodiment will be described with reference to FIGS. 4 and 7 to 12. 7 and 8 are explanatory diagrams of the third processing and the fourth processing, respectively, FIGS. 9 and 10 are explanatory diagrams of the fifth processing, and FIGS. 11 and 12 are explanatory diagrams of the sixth processing. The first and second processes will be described with reference to FIG. 7 to 12 mainly show characteristic portions for easy understanding of each process.

  The grid point resetting process includes the following processes (first process to sixth process). In the present embodiment, the first process to the sixth process are executed in order. However, the user can employ any number of one or more processes among a plurality of processes using a setting input unit (not shown).

As shown in FIG. 4, the first process is a process for setting grid points 44 based on the motion characteristics of the vehicle 1. That is, the initial grid points 43 in the region where the vehicle 1 cannot enter are removed based on the motion characteristics. Specifically, the vehicle 1 cannot travel in the non-setting areas D _L and D _R of the grid area 40 even when turning at the maximum turning angle on the mechanism from the current position. Therefore, the ECU 10 (grid area setting unit 12) removes the initial grid points 43 existing in the substantially fan-shaped non-setting areas D _L and D _R set in advance based on the turning performance.

  In the present embodiment, the non-setting area is set based on only the maximum turning angle without considering the speed and acceleration of the vehicle 1, but the non-setting area is set as a function of the speed and acceleration. Also good. For example, the maximum turning angle that can be operated may be set according to the speed and acceleration.

  Next, as shown in FIG. 4, the second process is a process of setting grid points 44 based on the driver's visual recognition characteristics. That is, a plurality of areas A1 to A4 are set in the grid area 40, and grid points 44 are set at different grid intervals for each area. As described above, all the initial grid points 43 are set as the grid points 44 in the region A2. On the other hand, in the areas A1 and A3, the grid interval is set to double in the X direction and the Y direction as compared with the area A2. That is, with the area A2 as a reference, the density of the grid points 44 in the areas A1 and A3 is reduced to ¼.

  Further, no grid point 44 is set in the area A4. Therefore, in the traveling direction of the vehicle 1, the further away from the area A <b> 2, the larger the grid interval and the less dense the grid points 44. In this embodiment, the grid points 44 are not set in the region A4. However, the grid points 44 may be set in the region A4 by further reducing the density of the grid points 44 compared to the region A3.

  The areas A1 to A4 based on the driver visual recognition characteristics are set in advance based on the following experiments on the driver's line-of-sight behavior and the vehicle avoidance operation with respect to the preceding vehicle. In this experiment, the vehicle 1 was run at various vehicle speeds in a situation where the preceding vehicle was located in front of the vehicle 1 (including diagonally forward), and the driver's line-of-sight direction and vehicle avoidance behavior were observed. According to this experimental result, when the preceding vehicle exists in the area A4, the driver did not pay attention to the preceding vehicle (that is, the line-of-sight direction was random).

  However, when the preceding vehicle reaches the area A3 in front of the vehicle 1, the driver's visual attention starts. That is, the line of sight begins to concentrate on the preceding vehicle, and the range of movement in the line of sight decreases. Such visual attention starts at a point where the vehicle head time THW (= inter-vehicle distance / vehicle speed) is 3.0 seconds (the boundary between the region A3 and the region A4) in the traveling direction of the vehicle 1 (directly in front). (Equivalent to the major axis length of the ellipse of A3).

  In particular, when the preceding vehicle is located diagonally forward of the vehicle 1, the travel distance (corresponding to half of the short axis length of the ellipse of A3) for up to 0.3 seconds (= lateral distance / vehicle speed) is on the side. Visual attention was given to the preceding car far away. This distance corresponds to the lateral distance between the two vehicles when the vehicle 1 passes by the side of the preceding vehicle. From these results, the elliptical shape forming the outer shape of the region A3 was specified.

  When the preceding vehicle reaches the area A2 in front of the vehicle 1, the driver starts driving avoidance behavior. That is, any one of the steering wheel, the brake pedal, and the accelerator pedal is started. Such an operation is started at a point where the vehicle head time THW (= inter-vehicle distance / vehicle speed) is 1.8 seconds (the boundary between the region A2 and the region A3) in the traveling direction of the vehicle 1 (A2 Equivalent to the major axis length of the ellipse).

  In particular, when the preceding vehicle is positioned obliquely forward of the vehicle 1, the preceding vehicle is a lateral distance of up to 1.5 m (corresponding to half the length of the short axis of the ellipse A2) to the side. On the other hand, driving avoidance action was performed. Based on these results, the elliptical shape forming the outer shape of the region A2 was specified.

  When the preceding vehicle reaches the area A1 in front of the vehicle 1, the driver performs an emergency avoidance action. That is, the driver suddenly operates the steering wheel and the brake pedal in order to avoid a collision with the preceding vehicle. Such an operation is started at the point where the collision margin time TTC (= inter-vehicle distance / relative speed) is 1.4 seconds (the boundary between the region A1 and the region A2) in the traveling direction of the vehicle 1. (Equivalent to the major axis length of the ellipse A1). Similarly, when the preceding vehicle is located on the side of the vehicle 1, the oval shape that forms the outer shape of the region A <b> 1 is identified by observing the position where the driving avoidance action is similarly started.

Region A4 is a region where the driver does not give visual attention. For this reason, in this embodiment, area | region A4 is excluded from the object of a driving | running route.
Moreover, although area | region A3 is an area | region where visual attention is performed, the danger of a collision with target objects (a preceding vehicle, an obstruction, etc.) is low. For this reason, in area | region A3, the necessity for performing fine or precise path | route position selection in the positional relationship with a target object is low. Therefore, in the area A3, the density of the grid points 44 is set to be relatively sparse.

  On the other hand, region A2 is a region where driving avoidance behavior is performed. For this reason, in order to maintain high driving comfort while avoiding a collision with an object, it is preferable that a finer or more precise route position selection is possible in the region A2. Therefore, in the area A2, the density of the grid points 44 is set relatively dense.

  Moreover, area | region A1 is an area | region where emergency avoidance action is performed. For this reason, in area A1, it is necessary to change a course direction greatly and to avoid collision with an object certainly. Therefore, in the area A1, the density of the grid points 44 is set to be relatively sparse. Note that the area A1 is not necessarily provided, and the area A1 may be set to an area where the grid points 44 are relatively dense like the area A2.

  Thus, in the second process, the density of the grid points 44 is set to be sparser in the areas A1, A3, and A4 than in the area A2, thereby reducing the number of grid points 44 as a whole than the number of initial grid points 43. doing. In the present embodiment, the initial grid points 43 are densely arranged (A2), and the grid points 44 are removed by removing some initial grid points 43, so that regions (A1, A3, A3, etc.) where the grid point density is sparse. A4) is set. However, the present invention is not limited to this, by arranging the initial grid points 43 relatively sparsely (A1, A3), and adding grid points, a region (A2) where the grid point density is dense is set and some of the grid points are set. By removing the initial grid points 43, a region (A4) with a sparse grid point density may be set.

  Next, as shown in FIG. 7, the third process is a process of setting grid points 44 according to the shape of the traveling road. That is, there are areas where finer or more precise route position selection is desired due to the shape of the travel path, and areas where it is not. For this reason, in the former, grid points are set densely (the grid interval is small), and in the latter, grid points are set sparsely (the grid interval is large). For example, if the route position can be selected more finely in a curve section than in a straight section, it is considered that the diversity of vehicle motion, safety, driving comfort, etc. are further enhanced.

  In FIG. 7, the traveling path 6 includes a straight section 6A, a curve section 6B, and a straight section 6C. The grid area 40 is set along the extending direction of the traveling path 6. When the ECU 10 specifies the curve section 6B, the grid is divided into areas corresponding to the curve section 6B and a section of a predetermined distance M before and after the curve section 40 (the entrance area immediately before the curve section 6B and the exit area immediately after the curve section 6B). An area 40a is set, and grid areas 40b and 40c are set before and after the grid area 40a.

  The grid points 44 are relatively densely arranged in the grid area 40a, and the grid points 44 are relatively sparsely arranged in the grid areas 40b and 40c. In the example shown in FIG. 7, the grid interval along the traveling direction Y in the grid region 40a is set to ½ of the grid interval between the grid regions 40b and 40c. In addition to or instead of this, the grid interval along the width direction X in the grid region 40a may be set smaller than the grid interval between the grid regions 40b and 40c. Moreover, the grid interval in the grid area 40a may be set smaller as the curvature radius of the curve section 6B is smaller.

  In the grid area 40a, the grid points 44 are densely arranged toward the curve center side (that is, the grid interval is set to be smaller). Specifically, the grid interval in the width direction X is set smaller toward the curve center side.

  In the present embodiment, in the third process, by adding additional grid points, regions (grid regions 40a) having different grid point densities (or grid intervals) are provided. However, alternatively, regions (grid regions 40b and 40c) having different grid point densities may be provided by removing some initial grid points from the initial region where the initial grid points 43 are set.

  Next, as shown in FIG. 8, the fourth process is a process of setting grid points 44 according to obstacles detected on the road or in the vicinity of the road. That is, in the surrounding area of the obstacle, since a finer or more precise route position selection is desired, the grid interval is set smaller than that in the other areas of the grid area.

  In the example shown in FIG. 8, the obstacle 3 exists on the travel path 6. When the ECU 10 specifies the obstacle 3, the ECU 10 sets a surrounding area 40 d of the obstacle 3 in the grid area 40. The surrounding area 40d is set around the obstacle 3 (a range within a predetermined distance from the obstacle 3). In the surrounding region 40d, in the adjacent region 40d1 adjacent to the obstacle 3 and in the outer region 40d2 outside the adjacent region 40d1, the grid interval along the traveling direction Y is 1 / of the grid interval in the grid region 40 outside the surrounding region 40d. 3 and 1/2 are set. Thus, in this embodiment, the grid interval is set smaller around the obstacle 3 as the obstacle 3 is closer (grid points 44 are arranged more densely).

  In the example illustrated in FIG. 8, the grid interval is changed to a small grid interval in the lateral region (width direction X) and the front / rear region (traveling direction Y) of the obstacle 3. However, the present invention is not limited to this, and the grid interval is changed to a small grid interval at least in the lateral direction region (width direction X) of the obstacle 3 so that the path for avoiding the obstacle 3 can be selected more finely or more precisely. do it.

  In the example shown in FIG. 8, the grid interval along the traveling direction Y is changed to a small grid interval. However, in addition or alternatively, the grid interval along the width direction X may be changed to a small grid interval. In particular, in the lateral region of the obstacle 3, the grid interval along the width direction X may be changed to a small grid interval.

  Further, in setting the grid interval in the surrounding area 40d, the absolute speed of the vehicle 1 or the relative speed with respect to the object may be considered. For example, the larger the absolute speed or the relative speed, the smaller the grid interval can be set. The ECU 10 can set the grid interval as a function of absolute speed or relative speed.

  Next, as shown in FIG. 9, the fifth process is a process of setting grid points 44 in accordance with the obstacle detected on the traveling road. The fifth process is executed subsequent to the fourth process when an obstacle is detected. When traveling while avoiding obstacles, there may be other (undetected) obstacles in the blind spot area of the obstacle. In addition, when the vehicle enters the blind spot area, the lateral acceleration increases and the driving comfort may be reduced. For this reason, the necessity to let a vehicle approach into a blind spot area is low. Therefore, grid points are not set in the blind spot area of the obstacle, or the grid interval is set larger than in other areas of the grid area.

  In the example shown in FIG. 9, the obstacle 3 exists on the travel path 6. When the obstacle 10 is specified, the ECU 10 sets the rear area of the obstacle 3 with respect to the vehicle 1 in the blind area 40e in the grid area 40. The blind spot area 40e is set in a range from the obstacle 3 to the rear of the predetermined distance (forward in the traveling direction of the vehicle 1). In the blind spot area 40e, the grid interval along the traveling direction X and / or the width direction Y is set larger than that in the other areas in the grid area 40. In the present embodiment, the grid interval is expanded by not setting the grid points 44 in the blind spot area 40e (that is, the initial grid points 43 are removed).

  In the blind spot area 40e, the grid interval may be decreased so that the distance from the obstacle 3 to the rear becomes closer to the grid interval of the other area (that is, the closer to the obstacle 3, the greater the grid interval). .

  Further, in setting the grid interval in the blind spot area 40e, the absolute speed of the vehicle 1 or the relative speed with respect to the object may be considered. For example, the larger the absolute speed or the relative speed, the larger (or smaller) the grid interval can be set. The ECU 10 can set the grid interval of the blind spot area 40e as a function of the absolute speed or the relative speed.

  Further, the size of the blind spot area 40e may be set in consideration of the absolute speed of the vehicle 1 or the relative speed with respect to the object. For example, the larger the absolute speed or the relative speed, the larger the blind spot area 40e from the obstacle 3 to the rear. The ECU 10 can set the predetermined distance that the blind spot area 40e extends as a function of the absolute speed or the relative speed.

  Further, in the fifth process, as shown in FIGS. 8 and 10, the grid interval of the surrounding area of the obstacle existing on or near the traveling road is different from the other areas of the grid area according to the attribute of the obstacle. Set differently. That is, by setting the grid points so as to match the attributes of the obstacle in the surrounding area of the obstacle, it is possible to select a finer or more precise route position.

  In the example shown in FIGS. 10A to 10C, a pedestrian 4 is present near the traveling path 6. In FIG. 10A, the pedestrian 4 stands in the state of being stopped near the traveling path 6, in FIG. 10B, crossing the traveling path 6, and in FIG. 10C, on the traveling path 6. Walking toward the traveling direction of the vehicle 1.

  8 and 10A are cases where an object is detected. In FIG. 8, the object is the parked vehicle 3, and in FIG. 10A, the object is the pedestrian 4. ECU10 sets the grid space | interval of surrounding area 40d and 40f1 according to the attribute (in this case, a vehicle or a pedestrian as a kind of target object) of a target object. That is, the pedestrian 4 is set to have a smaller grid interval in the surrounding area than the parked vehicle 4. Moreover, you may change the magnitude | size of a surrounding area according to the kind of target object.

  The size of the surrounding area and the grid interval may be set depending on whether the attribute of the object is a moving object (vehicle, pedestrian, etc.) or a stationary object (falling object, construction fence, etc.). . That is, the size of the surrounding area is set larger for the moving body than the stationary body, and the grid interval is set smaller.

  FIGS. 10 (A) to 10 (C) are cases where a pedestrian 4 is detected. In FIG. 10 (A), the pedestrian 4 is stationary, and in FIG. 10 (B). The pedestrian 4 is moving in the width direction X, and the pedestrian 4 is moving in the traveling direction Y in FIG. ECU10 sets the magnitude | size and grid space | interval of surrounding area 40f1, 40f2, 40f3 according to the attribute (in this case, moving speed, moving direction) of a target object. That is, when the pedestrian 4 is moving, the surrounding area is enlarged forward in the moving direction. In addition, the grid interval is set smaller in the area in the front direction of movement than in the area in the rear direction of movement.

  As shown in FIG. 10C, the grid interval is set smaller in the front area than in the rear area in the moving direction of the pedestrian 4. This makes it possible to perform finer or finer route position selection in the front region of the object.

  Further, regardless of whether the pedestrian 4 is moving or stationary, the grid area may be set to be smaller in the front area in the predicted direction of movement of the pedestrian than in the rear area. The attribute in this case is the expected movement direction or the movable direction. The expected movement direction is ahead of the object (pedestrian, vehicle, etc.).

  Further, in setting the grid intervals in the surrounding areas 40f1 to 40f3, the absolute speed of the vehicle 1 or the relative speed with respect to the object may be considered. For example, the larger the absolute speed or the relative speed, the smaller the grid interval can be set. The ECU 10 can set the grid interval as a function of absolute speed or relative speed.

  Note that the fifth process is different depending on the condition of the obstacle. For this reason, a priority order is set for each process. For example, a grid point is not normally set in the blind spot area of the obstacle (moving body), but when the blind spot area is the traveling direction of the obstacle, a grid point is set in the blind spot area.

  Next, in the sixth process, as shown in FIG. 11 (straight section) and FIG. 12 (curve section), the grid interval of the specific area is different from the other areas of the grid area based on the travel history information of the vehicle 1. It is a process to set. That is, by reflecting the driver's driving preference and habit in the grid interval, it is possible to select a route position that is more in line with the driver's preference.

  In the example shown in FIG. 11, the vehicle 1 is traveling on a straight section of the traveling path 6. The ECU 10 determines whether or not the vehicle 1 tends to travel in a specific width direction position in the lane based on the travel history information. In this determination processing, for example, an average value of the position in the width direction in the lane in which the vehicle 1 has traveled is calculated based on travel history information for a straight section for a predetermined period. Thereby, the position in the width direction where the vehicle 1 is expected to travel generally is specified. Note that the position in the width direction of the lane may be divided into a plurality of times, and the total time or distance passing through each division width may be calculated to identify one division width having the largest travel time or travel distance. The ECU 10 determines that there is a specific tendency when the specified position in the width direction is separated from the center of the lane by a predetermined distance or more.

  When the ECU 10 determines that there is a specific tendency related to the position in the width direction, the grid point 44 or the initial grid point is set so that the grid interval (width direction) near the specified width direction position is smaller than the other width direction positions. 43 (see FIG. 3) is coordinate-transformed by a predetermined function. Thereby, as shown in FIG. 11, the grid width (width direction) in the specific area | region 40g is set smaller than another area | region.

  In the example shown in FIG. 12, the vehicle 1 is traveling on the curve section of the travel path 6. When the ECU 10 detects a curve section ahead of the vehicle 1, the ECU 10 determines whether the vehicle 1 tends to travel in a specific width direction position in the lane of the curve section based on the travel history information. In this determination process, for example, the ECU 10 travels in a plurality of travel sections (an entrance section, a central section, an exit section, etc. along the traveling direction Y) of the curve section based on the travel history information about the curve section. Calculate the average value of the position in the width direction in the lane. Thereby, the width direction position of each traveling section where the vehicle 1 is expected to travel generally is specified. The ECU 10 determines that there is a specific tendency when the specified width direction position is separated from the center of the lane by a predetermined distance or more in one or more travel sections.

  When the ECU 10 determines that the curve section has a specific tendency regarding the width direction position, the initial value is set so that the grid width in the width direction near the width direction position specified in each travel section is smaller than the other width direction positions. The grid point 43 is coordinate-transformed by a predetermined function.

  The example shown in FIG. 12 shows a grid region 40 formed when the vehicle 1 tends to travel out of the curve. In this example (out-in-out), in the entrance section 40h1 of the curve section, the grid interval (width direction) of the outer region in the lane away from the center of the curve is set small, and the grid interval of the inner region is set relatively large. Is done. Then, as approaching the central section 40h2 in the curve section, the grid interval (width direction) of the inner region in the lane is set to be small, and the grid interval of the outer region is set to be relatively large. Although not shown, one or more sections are also set between the section 40h1 and the section 40h2.

  In the above embodiment, in order to change the grid interval (or to change the density of grid points), additional grid points 44 may be added to the initial grid points 43, or some initial grid points. Or both of them may be executed.

Next, the operation of the vehicle driving support system of this embodiment will be described.
In the present embodiment, the grid area setting unit 12 sets the grid interval based on the travel history information, and the travel route candidate calculation unit 13 uses the grid points 44 set by the grid region setting unit 12 to run the travel route candidates. Can be calculated (see FIGS. 11 and 12). Therefore, compared with the conventional case where the grid points of the grid area are set without considering the travel history information, the present embodiment can calculate a target travel route suitable for the driver's driving preference.

  In the present embodiment, the travel history information includes information related to the travel position of the vehicle 1 in the lane width direction. Thus, according to the present embodiment, since the travel history information includes travel position information in the lane width direction, when the driver tends to travel in a specific width direction position of the lane, the driver's driving preference A target travel route suitable for the vehicle can be calculated.

  In the present embodiment, when it is determined that the vehicle 1 tends to travel in a specific width direction position in the lane of the travel path 6 based on the travel history information, the grid area setting unit 12 determines that the specific width direction The grid interval in the width direction in the vicinity of the position is set smaller than the grid interval in the width direction in the width direction position other than in the vicinity of the specific width direction position (see FIGS. 11 and 12). As a result, in this embodiment, when there is a tendency to travel in a specific position in the width direction, by setting the grid interval of the position in the width direction to be small, the travel route candidates are more precisely or more precisely set at the position. It becomes possible to calculate. Thereby, the target travel route suitable for the driving preference of the driver can be calculated.

  In the present embodiment, when it is determined that the vehicle 1 tends to travel to the right side or the left side of the center in the lane of the travel path 6 based on the travel history information (see FIG. 11), grid area setting is performed. The unit 12 sets the grid interval in the width direction on the right side or the left side determined to have a tendency to run away from the vehicle to be smaller than the grid interval in the width direction on the opposite side. Accordingly, in the present embodiment, when the vehicle 1 tends to travel on the right side or the left side of the lane, the grid interval at the position in the width direction (region 40g) is set to be smaller, or more precisely at the position. It becomes possible to calculate the travel route candidate more precisely. Thereby, the target travel route suitable for the driving preference of the driver can be calculated.

  In the present embodiment, when it is determined that the vehicle 1 tends to travel in the inner area near the center of the curve in the curve section based on the travel history information (see FIG. 12), the grid area setting unit 12 In (region 40h2), the grid interval in the width direction in the inner region is set smaller than the grid interval in the width direction in the outer region away from the curve center. As a result, in the present embodiment, when the vehicle 1 tends to travel on a specific route in a curve section, the grid interval near the specific route is set small, so that the vicinity of the route is more precisely or more precisely. It is possible to calculate the travel route candidate precisely. Thereby, the target travel route suitable for the driving preference of the driver can be calculated.

  In this embodiment, when it is determined based on the travel history information that the vehicle 1 tends to travel in an outer region away from the curve center in the section (entrance section 40h1) before the curve section (see FIG. 12). The grid area setting unit 12 sets the grid distance in the width direction in the outer area in the section (entrance section 40h1) before the curve section to be smaller than the grid distance in the width direction in the inner area near the center of the curve. Accordingly, in the present embodiment, when the vehicle 1 tends to enter the curve section from the out side, the grid distance on the out side is set small in the section before the curve section, so that the out side can be more precisely set. Alternatively, it is possible to calculate the travel route candidate more precisely. Thereby, the target travel route suitable for the driving preference of the driver can be calculated.

1 vehicle 3 obstacle 4 pedestrian 5,6 roadway 40 grid regions 41x, 41y grid lines 42 grid section 43 initial grid points 44 grid points 100 the vehicle driving assist system D _L, D _R unset region Gx, Gy grid spacing R Target travel

Claims (5)

A travel path information acquisition unit that acquires travel path information on the travel path of the vehicle;
A grid area setting unit that sets a grid area composed of a plurality of grid points on the travel path based on the travel path information;
A travel route candidate calculation unit that calculates a plurality of travel route candidates by a route search using a plurality of grid points in the grid region;
In a vehicle driving support system comprising: a target travel route calculation unit that selects one travel route candidate as a target travel route based on a predetermined condition from the plurality of travel route candidates;
The grid area setting unit sets a grid interval between adjacent grid points based on travel history information related to the past travel state of the vehicle ,
When it is determined based on the travel history information that the vehicle has a tendency to travel in a specific width direction position in the lane of the travel path, the grid area setting unit is configured to detect the width direction in the vicinity of the specific width direction position. The grid interval is set to be smaller than the grid interval in the width direction at a position in the width direction other than the vicinity of the specific position in the width direction . When it is determined based on the travel history information that the vehicle tends to travel to the right or left side of the center in the lane of the travel route, the grid area setting unit tends to travel side by side The vehicle driving support system according to claim 1, wherein the grid interval in the width direction on the right side or the left side determined to be smaller than the grid interval in the width direction on the opposite side is set. When it is determined based on the travel history information that the vehicle has a tendency to travel in an inner area close to the center of the curve in the curve section, the grid area setting unit is configured to use the grid in the width direction in the inner area in the curve section. The vehicle driving support system according to claim 1 or 2 , wherein the interval is set to be smaller than the grid interval in the width direction in the outer region away from the curve center. When it is determined based on the travel history information that the vehicle has a tendency to travel in an outer area away from the center of the curve in the section before the curve section, the grid area setting unit is configured to perform the operation in the section before the curve section. the grid spacing in the width direction of the outer region is set smaller than the grid spacing in the width direction of the inner region closer to the curve center, the vehicle driving assist system according to any one of claims 1-3. A vehicle driving support method executed by a vehicle control device,
A road information detection step for detecting road information about the road of the vehicle;
A grid area setting step for setting a grid area composed of a plurality of grid points on the travel path based on the travel path information;
A travel route candidate calculation step for calculating a plurality of travel route candidates by route search using a plurality of grid points in the grid area;
A target travel route calculation step of selecting one travel route candidate as a target travel route based on a predetermined condition from the plurality of travel route candidates,
The grid area setting step includes a step of setting a grid interval between adjacent grid points based on travel history information related to a past travel state of the vehicle ,
When it is determined based on the travel history information that the vehicle has a tendency to travel in a specific width direction position in the lane of the travel path, the grid region setting step includes the width direction in the vicinity of the specific width direction position. A vehicle driving support method comprising: setting the grid interval smaller than the grid interval in the width direction at a width direction position other than the vicinity of the specific width direction position .

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