JP2020196399A - Travel support method and travel support apparatus - Google Patents

Abstract

To provide a travel support method and a travel support apparatus capable of suppressing wobble of an own vehicle due to variation in a road width when the own vehicle passes through a section where the road width varies.SOLUTION: A vehicular travel support method, to be executed by a processor, includes the steps of: obtaining information on a travel-road boundary representing a boundary between a travel road of an own vehicle and a zone other than the aforementioned travel road; computing travel-road boundary roughness of a first travel-road boundary being the travel-road boundary on a left side relative to a travel direction of the own vehicle, on the basis of the information on the travel-road boundary; computing travel-road boundary roughness of a second travel-road boundary being the travel-road boundary on a right side relative to the travel direction of the own vehicle, on the basis of the information on the travel-road boundary; and generating a target travel route on the basis of a result of comparison between the travel-road boundary roughness computed on the first travel-road boundary and the travel-road boundary roughness computed on the second travel-road boundary, and controlling the own vehicle on the basis of the target travel route.SELECTED DRAWING: Figure 1

Description

The present invention relates to a travel support method and a travel support device that support the travel of a vehicle.

As a method of aligning the own vehicle with the center of the lane, the future lane width and the neighboring lane width are calculated, and the lane branch or the lane confluence is detected based on the difference between the future lane width and the neighboring lane width. Determine on which side of the vehicle the lane branch or lane confluence occurred and one side based on the left or right crossoid corresponding to the side of the lane where the lane branch or lane confluence did not occur. A method of performing a typical lane alignment calculation is known (for example, Patent Document 1).

Special Table 2017-520056 Gazette

In the above-mentioned prior art, when the own vehicle passes through a section where the road width changes other than the lane branch or the lane confluence, the calculation of lane alignment is not performed, and the own vehicle fluctuates as the road width changes. There is a problem.

An object to be solved by the present invention is a traveling support method and a traveling support device capable of suppressing wobbling of the own vehicle due to the change of the road width when the own vehicle passes through a section where the road width changes.

The present invention acquires information on the track boundary indicating the boundary between the track of the own vehicle and other than the track, and based on the information on the track boundary, the first track boundary which is the track boundary on the left side with respect to the traveling direction of the own vehicle. The roughness of the runway boundary is calculated, and based on the information of the runway boundary, the roughness of the runway boundary is calculated for the second runway boundary which is the right side runway boundary with respect to the traveling direction of the own vehicle, and the first runway is calculated. Based on the result of comparing the roughness of the track boundary calculated for the boundary and the roughness of the track boundary calculated for the second track boundary, the target travel route of the own vehicle is generated, and the own vehicle is controlled based on the target travel route. By doing so, the above problem is solved.

According to the present invention, when the own vehicle passes through a section where the road width changes, it is possible to suppress the wobbling of the own vehicle due to the change in the road width.

FIG. 1 is a block diagram showing a traveling support device according to an embodiment of the present invention. FIG. 2 is a diagram for explaining a track boundary. FIG. 3 is a diagram for explaining the track width. FIG. 4 is a diagram for explaining a method of calculating the roughness of the runway boundary. FIG. 5 is a diagram for explaining a target traveling route according to the first embodiment. FIG. 6 is a block diagram showing a flow of control processing according to the first embodiment. FIG. 7 is a diagram for explaining the function realized by the control device of the second embodiment. FIG. 8 is a diagram for explaining a target traveling route according to the second embodiment. FIG. 9 is a block diagram showing a flow of control processing according to the second embodiment. FIG. 10 is a diagram for explaining a target section for calculating the roughness of the track boundary.

<< First Embodiment >>
Hereinafter, a vehicle traveling support device and a method according to an embodiment of the present invention will be described with reference to the drawings. In the present embodiment, the present invention will be described by exemplifying a traveling support device mounted on a vehicle. Further, in the present embodiment, the present invention will be described by taking as an example a scene in which the own vehicle travels in a section where the road width is widened.

FIG. 1 is a diagram showing a configuration of a vehicle traveling support device 100 according to an embodiment of the present invention. As shown in FIG. 1, the traveling support device 100 according to the present embodiment includes a vehicle position detection device 110, a map database 120, a vehicle speed sensor 130, a distance measurement sensor 140, a camera 150, and a drive mechanism 170. , The control device 180 is provided. These devices are connected by a CAN (Controller Area Network) or other in-vehicle LAN in order to exchange information with each other.

The own vehicle position detection device 110 includes a GPS unit. The own vehicle position detection device 110 detects radio waves transmitted from a plurality of satellite communications by a locator (GPS antenna), and periodically acquires the position information of the own vehicle. The own vehicle position detection device 110 detects the current position of the own vehicle based on the acquired position information of the own vehicle, the angle change information acquired from the gyro sensor (not shown), and the vehicle speed acquired from the vehicle speed sensor 130. To do. In addition, the own vehicle position detection device 110 can also detect the position of the own vehicle by using a well-known map matching technique. The position information of the own vehicle detected by the own vehicle position detection device 110 is output to the control device 180.

Map information is stored in the map database 120. The map information stored in the map database 120 includes road attribute information at each map coordinate. Examples of road attributes include curves, slopes, intersections, interchanges, narrow roads, straight roads, and confluences. These road attributes are examples and do not limit the road attributes. Road attributes include road shape information.

In addition, the map information includes information on the track boundary. The track boundary is the boundary between the track of the own vehicle and the rest. The runway of the own vehicle is a road for the own vehicle to travel. In other words, the track boundary is the boundary that forms the road on which the own vehicle travels. The track boundary is located on each of the left and right sides with respect to the traveling direction of the own vehicle. The form of the track boundary is not particularly limited, and examples thereof include road markings and road structures. Examples of the track boundary of the road marking include a lane boundary line and a center line. Further, the runway boundary of the road structure includes, for example, a median strip, a guardrail, a curb, a tunnel, or a side wall of a highway. Note that the track boundary is set in advance in the map information for a point (for example, inside an intersection) where the track boundary cannot be clearly specified. The preset track boundary is a fictitious track boundary, not a road marking or road structure that actually exists.

The map information also includes traffic rule information that the vehicle must comply with when traveling. The traffic rule information includes, but is not limited to, for example, pausing on the route, parking / stopping prohibition, slowing down, speed limit (legal speed), and lane change prohibition. Traffic rule information is specified for each lane. Note that these pieces of information included in the map information are defined by nodes and links connecting the nodes (also referred to as road links).

The vehicle speed sensor 130 measures the rotational speed of a drive system such as a drive shaft, and detects the traveling speed of the own vehicle (hereinafter, also referred to as vehicle speed) based on the rotation speed. The vehicle speed information of the own vehicle detected by the vehicle speed sensor 130 is output to the control device 180.

The ranging sensor 140 detects an object existing around the own vehicle. Further, the distance measuring sensor 140 calculates the relative distance and the relative speed between the own vehicle and the object. Objects include, for example, lane boundaries, centerlines, medians, guardrails, curbs, tunnels or side walls of highways. Examples of other objects include automobiles (other vehicles) other than the own vehicle, motorcycles, bicycles, road signs, traffic lights, pedestrian crossings, and the like. The information of the object detected by the distance measuring sensor 140 is output to the control device 180. As such a distance measuring sensor 140, a laser radar, a millimeter wave radar, or the like (LRF or the like) can be used. The number of distance measuring sensors 140 is not particularly limited, and the distance measuring sensors 140 are provided, for example, in the front, side, and rear of the own vehicle. As a result, the distance measuring sensor 140 detects an object existing in the entire periphery of the own vehicle.

The camera 150 captures images of roads and / or objects existing around the vehicle. In the present embodiment, the camera 150 images the front of the own vehicle. The image information captured by the camera 150 is output to the control device 180. The camera 150 is a camera that images the front of the own vehicle and / or a camera that images the side of the own vehicle.

The input device 160 is an operating member that can be operated by the driver. In the present embodiment, the driver can set on / off of the automatic driving control by operating the input device 160.

The drive mechanism 170 includes an engine and / or a motor (power system), a brake (braking system), a steering actuator (steering system), and the like for automatically traveling the own vehicle. In the present embodiment, the operation of the drive mechanism 170 is controlled by the control device 180 when the automatic operation control described later is performed.

The control device 180 is a computer having a processor, and is a ROM (Read Only Memory) that stores a program for controlling the running of the own vehicle, and a CPU (Central Processing Unit) that executes the program stored in the ROM. ) And a RAM (Random Access Memory) that functions as an accessible storage device. As the operating circuit, instead of or in addition to the CPU (Central Processing Unit), MPU (Micro Processing Unit), DSP (Digital Signal Processor), ASIC (Application Specific Integrated Circuit), FPGA (Field Programmable Gate Array), etc. Can be used.

The control device 180 executes a program stored in the ROM by the CPU to execute a track boundary information acquisition function, a track width calculation function, a track center line generation function, a track boundary evaluation function, an offset calculation function, and a target travel route generation function. , Realizes a running control function that controls the running of the own vehicle. Hereinafter, each function included in the control device 180 will be described. In addition to the functions described below, the control device 180 also has other functions such as a function of detecting and estimating the position of the own vehicle.

The control device 180 acquires information on the track boundary indicating the boundary between the track of the own vehicle and other than the track by the track boundary information acquisition function. The track boundary information includes at least information on the type of track boundary, the position of the track boundary, and the shape of the track boundary. Types of track boundaries include, for example, lane boundaries, center lines, medians, guardrails, curbs, tunnels, and side walls of highways. The position of the track boundary is indicated by, for example, the position relative to the own vehicle or the latitude and longitude information on the map. The shape of the runway boundary is the shape of the runway boundary represented by a surface along the traveling direction of the own vehicle when the runway of the own vehicle is viewed from a bird's-eye view. The shape of the runway boundary does not show information representing the shape of the road such as a straight road or a curve, but shows more detailed information. For example, when the road has a curved shape, the shape of the track boundary is indicated by the curvature or radius of curvature at each point of the curve.

As a method of acquiring the information of the runway boundary, there is a method of acquiring from the map database 120. For example, the control device 180 acquires the route information on which the own vehicle is scheduled to travel from the navigation system (not shown). The control device 180 identifies the lane in which the own vehicle travels on the planned travel route from the map information stored in the map database 120. The control device 180 acquires information on the type of the track boundary, the position of the track boundary, and the shape of the track boundary based on the information of the road including the specified lane.

The control device 180 can also acquire information on the track boundary from the distance measuring sensor 140 and / or the camera 150. For example, the control device 180 acquires information on the distance to the runway boundary located on the left and right with respect to the traveling direction of the own vehicle from the detection result by the distance measuring sensor 140, and obtains information on the current position of the own vehicle and the runway boundary with respect to the own vehicle. Information on the position of the track boundary and the shape of the track boundary is acquired based on the relationship with the relative distance of. Further, for example, the control device 180 can also acquire the type of the track boundary and the position information of the track boundary from the image captured by the camera 150. In order to acquire the information on the runway boundary, it is not always necessary to use all of the map information stored in the map database 120, the detection result by the distance measuring sensor 140, and the image captured by the camera 150, and the control device 180 is at least Obtain information on the track boundary using any one of them.

FIG. 2 is a diagram for explaining a track boundary. 2 (A) shows a situation where the traffic lane L ₁ which bus stop 1 is provided the vehicle V passes. 2 (A) is an overhead view of the traffic lane L ₁ from above. Since the bus stop 1 is provided to where the cut is placed against pavement S, lane width of lanes L ₁ is spread partly in the vicinity of bus stops 1. Arrows _{D 1} shown in FIG. 2 (A) shows the traveling direction of the host vehicle V.

In the example of FIG. 2A, the control device 180 acquires information on the track boundary forming the track of the own vehicle V. The control device 180 acquires information on the track boundary located on the left side of the track of the own vehicle V. For example, the control device 180 recognizes the curb 2 (solid line) located on the left side of the traveling direction of the own vehicle V as the first track boundary A (dashed line) from the image captured by the camera 150. Further, the control device 180 acquires, for example, information on the position and shape of the curb 2 as information on the first track boundary A from the detection result of the distance measuring sensor 140.

Further, in the example of FIG. 2A, the control device 180 acquires information on the track boundary located on the right side of the track of the own vehicle V. For example, the control device 180 recognizes the center line 3 (dotted line) located on the right side of the traveling direction of the own vehicle V as the second runway boundary B (one-turn chain line) from the image captured by the camera 150. Further, the control device 180 acquires, for example, information on the position and shape of the center line 3 as information on the second track boundary B from the detection result of the distance measuring sensor 140.

In the following description, for convenience of explanation, among the track boundaries forming the track of the own vehicle, the track boundary on the left side with respect to the traveling direction of the own vehicle is referred to as the first track boundary, and is referred to as the traveling direction of the own vehicle. On the other hand, the track boundary on the right side will be referred to as a second track boundary.

In the example of FIG. 2A, the first track boundary A is composed of the curb 2, and the second track boundary B is composed of the center line 3. Even if the types of the left and right track boundaries are different, the control device 180 acquires information on the position and shape of the track boundary for each of the first track boundary and the second track boundary by the track boundary information acquisition function. Can be done.

Figure 2 (B) shows a situation where the vehicle V passes through the intersection 4 along the lane L _2. 2 (B) is an overhead view of the lane L ₂ from above. It is assumed that there is no road marking (lane boundary line) in the intersection 4 that can specify the road boundary on the left side with respect to the traveling direction of the own vehicle V. The arrow D ₂ shown in FIG. 2B indicates the traveling direction of the own vehicle V.

In the example of FIG. 2 (B), the control device 180 acquires the information of the track boundary forming the track of the own vehicle V as in the example of FIG. 2 (A). The control device 180 acquires information on the track boundary located on the left side of the track of the own vehicle V. For example, the control device 180 recognizes the guardrail 5 (solid line) and the guardrail 6 (solid line) located on the left side of the traveling direction of the own vehicle V as the first track boundary A (one-turn chain line) from the captured image of the camera 150. To do. Further, the control device 180 acquires, for example, information on the positions and shapes of the guardrail 5 and the guardrail 6 as information on the first track boundary A from the detection result of the distance measuring sensor 140. Further, the control device 180 recognizes, for example, a fictitious boundary line 7 (dotted line) preset as a track boundary in the intersection 4 as a first track boundary A (one-turn chain line) from the map information stored in the map database 120. To do. Further, the control device 180 acquires, for example, information on the position and shape of the fictitious boundary line 7 as information on the first track boundary A from the map information stored in the map database 120. The fictitious boundary line 7 is information included in the map information and is a preset boundary line.

Further, in the example of FIG. 2B, the control device 180 acquires information on the track boundary located on the right side of the track of the own vehicle V. For example, the control device 180 recognizes the center line 8 (broken line) located on the right side of the traveling direction of the own vehicle V as the second runway boundary B (one-turn chain line) from the image captured by the camera 150. Further, the control device 180 acquires, for example, the position and shape information of the center line 8 as the information of the second track boundary B from the detection result of the distance measuring sensor 140.

In the example of FIG. 2B, the first track boundary A is composed of a guardrail 5, a guardrail 6, and a fictitious boundary line 7 included in the map information, and the second track boundary B is composed of a center line 8. There is. Even if the first track boundary and / or the second track boundary is composed of a plurality of types, the control device 180 uses the track boundary information acquisition function to determine the first track boundary and the second track boundary, respectively. Information on the position and shape of the track boundary can be obtained.

Returning to FIG. 1, the functions realized by the control device 180 will be described. The control device 180 calculates the track width, which is the width of the track of the own vehicle, by the track width calculation function. The track width indicates the distance between the first track boundary and the second track boundary. The control device 180 calculates the distance between the first track boundary and the second track boundary in the vehicle width direction of the own vehicle as the track width. Further, the control device 180 calculates the lane width in a predetermined section of the lane in which the own vehicle is scheduled to travel. The target section for which the control device 180 calculates the track width will be described later. Further, the control device 180 calculates the track width at predetermined intervals with respect to the traveling direction of the own vehicle.

FIG. 3 is a diagram for explaining the track width. Since the scenes shown in FIGS. 3 (A) and 3 (B) are the same as the scenes shown in FIG. 2 (A), the description of FIG. 2 (A) will be appropriately incorporated. In the example of FIG. 3A, the control device 180 calculates the track width Δd ₁ to the track width Δd ₆ , which is the distance between the first track boundary A and the second track boundary B in the vehicle width direction of the own vehicle V. To do. In the example of FIG. 3A, six track widths are calculated as the track widths of the own vehicle V, but the number of track widths is not particularly limited. The controller 180 may calculate more than six or less than six track widths.

Further, FIG. 3B is another example of the track width calculated by the track width calculation function. The control device 180 can change the direction of the track width from the vehicle width direction of the own vehicle to the direction perpendicular to the center line of the first track boundary and the second track boundary. The control device 180 changes the direction of the track width and calculates the track width. When the track center line, which is the center line of the first track boundary and the second track boundary, is generated by the track center line generation function described later, the control device 180 determines the track width in the direction perpendicular to the generated track center line. Calculate the track width by regarding it as the direction. In the following description, the center line of the first track boundary and the second track boundary will be referred to as a track center line.

In the example of FIG. 3B, the control device 180 generates the track center line C of the own vehicle V. Controller 180 defines a vertical track center line C as the direction of the track width, to calculate the track width Δd ₁ ^{'~Δd _6'} is the distance between the first lane boundary A and the second lane boundary B ..

Returning to FIG. 1, the functions realized by the control device 180 will be described. The control device 180 uses the track center line generation function to generate the center line in the track of the own vehicle as the track center line. The control device 180 generates a track center line based on the position or shape information of the first track boundary and the second track boundary. The shape or position information of the first track boundary and the second track boundary is reflected in the track center line. As shown in the example of FIG. 3B, the track center line C bulges to the left with respect to the traveling direction of the own vehicle V in the vicinity of the bus stop 1.

The control device 180 evaluates the roughness of the first track boundary and the second track boundary by the track boundary evaluation function. The roughness of the runway boundary is the amount of change in the orientation of the own vehicle when the own vehicle travels along the runway boundary. The case where the own vehicle travels along the track boundary does not indicate that the own vehicle actually traveled along the track boundary, but indicates a case where it is assumed that the own vehicle traveled along the track boundary. In other words, the roughness of the track boundary is a parameter of the track boundary that indicates how much the direction of the own vehicle is affected if the own vehicle travels along the runway boundary. The greater the roughness of the track boundary, the greater the degree of reflection in the shape of the track centerline, and the greater the effect on the direction of the own vehicle. For example, when the own vehicle is driven along the center line of the runway, the larger the roughness of the runway boundary, the greater the change in the direction (also referred to as the posture angle) of the own vehicle. In the example of FIG. 3B, when the own vehicle V travels along the track center line C, the own vehicle V slightly changes its direction before and after passing through the bus stop 1, so that the own vehicle V is a bus stop. It sways in the width direction when passing 1. Therefore, in the present embodiment, when the own vehicle travels in the section where the road width is widened, the wobbling of the own vehicle due to the change of the road width is suppressed by using the method described below.

A method of calculating the roughness of the track boundary will be described with reference to FIG. FIG. 4 is a diagram for explaining a method of calculating the roughness of the runway boundary. Since FIG. 4 is the same scene as FIG. 2 (A), the description of FIG. 2 (A) is appropriately incorporated.

As shown in the example of FIG. 4, the control device 180 divides the first track boundary A and the second track boundary B into a plurality of sections, respectively. In the example of FIG. 4, the control device 180 divides the first track boundary A and the second track boundary B into nine sections, respectively. The line segments a ₁ to ₉ shown in FIG. 4 are line segments constituting the first track boundary A, and each line segment a indicates the first track boundary A in each section. Line segments a in each section are adjacent to each other in the order of line segment a ₁ to line segment a ₉ . Further, the line segment b ₁ to the line segment b ₉ are line segments constituting the second runway boundary B, and each line segment b indicates the second runway boundary B in each section. Line segments b in each section are adjacent to each other in the order of line segment b ₁ to line segment b ₉ . In the example of FIG. 4, the track boundary is divided into nine sections, but the number of sections that divide the track boundary is not particularly limited. The controller 180 may divide the track boundary in more than nine or less than nine sections.

When the track boundary is divided into a plurality of sections, the control device 180 calculates an angle formed at the track boundaries of adjacent sections (also referred to as an angle difference of the track boundaries) based on the position or shape of the track boundaries. In addition, each of the adjacent sections is also referred to as a first section and a second section (a section adjacent to the first section). For example, in the example of FIG. 4, the line segment a ₁ is referred first lane boundary A in the first section, the line segment a ₂ and the first lane boundary A in the second section.

In the example of FIG. 4, the control device 180 for the first lane boundary A, the angle difference between the line segment _{a 1} and the line segment _{a 2,} the angle difference between the line segment _{a 2} and a line segment _{a 3,} · · ·, segment angular difference a ₇ and a line segment _{a 8,} and calculates the angular difference between the line segment _{a 8} and a line segment _{a 9.} In FIG. 4, Δθ ₁ indicates the angle difference between the line segment a ₂ and the line segment a ₃ , Δθ ₂ indicates the angle difference between the line segment a ₄ and the line segment a ₅ , and Δθ ₃ indicates the angle difference between the line segment a ₆ and the line segment a ₆ . The line segment a ₇ is shown, and Δθ ₄ shows the angle difference between the line segment a ₈ and the line segment a ₉ .

Further, in the control device 180, similarly, for the second runway boundary B, the angle difference between the line segment b ₁ and the line segment b ₂ , the angle difference between the line segment b ₂ and the line segment b ₃ , ..., The line segment b. The angle difference between ₇ and the line segment b _{8 and} the angle difference between the line segment b ₈ and the line segment b ₉ are calculated. In the example of FIG. 4, since the shape of the second track boundary B reflects the linear center line 3, the second track boundary B is different from the first track boundary A and is a track boundary of adjacent sections. The angle formed by is zero, and there is no angle difference at the track boundary.

When the control device 180 calculates each of the angles formed at the runway boundaries of the adjacent sections, the control device 180 calculates the integrated value of the angles integrated over the target section as shown by the following equations (1) and (2).

ただし、上記式（１）及び式（２）において、ｉは隣り合う区間の走路境界で形成される角度の数を示す。また上記式（１）において、Ｓ_θＬは第１走路境界における角度の積算値を示し、Δθ_Ｌｉは隣り合う区間の第１走路境界で形成される角度を示す。また上記式（２）において、Ｓ_θＲは隣り合う区間の第２走路境界で形成される角度の数を示し、Δθ_Ｒｉは隣り合う区間の第２走路境界で形成される角度を示す。

However, in the above equations (1) and (2), i indicates the number of angles formed at the track boundaries of adjacent sections. Further, in the above equation (1), S _{θ L} indicates the integrated value of the angles at the first track boundary, and Δθ _Li indicates the angle formed at the first track boundary of the adjacent sections. Further, in the above equation (2), S _θR indicates the number of angles formed at the second track boundary of the adjacent sections, and Δθ _Ri indicates the angles formed at the second track boundary of the adjacent sections.

The control device 180 uses the integrated value _SθL of the angle at the first track boundary calculated using the above equation (1) as the roughness of the first track boundary, and is calculated using the above equation (2). The integrated value S _θR of the angles at the two track boundaries is defined as the roughness of the second track boundary. Then, the control device 180 identifies the runway boundary having a small roughness by comparing the roughness of the first runway boundary with the roughness of the second runway boundary. In the example of FIG. 4, the first track boundary A has a shape that reflects the space where the bus stop 1 is provided (a shape in which the road width is partially widened), and the second track boundary B is a linear center. The shape reflects the line 3. As a result of calculation by the control device 180 using the above equations (1) and (2), the integrated value S _θR of the angle at the second track boundary B is smaller than the integrated value S _θL of the angle at the first track boundary A. Become. The control device 180 _compares the integrated value S _θL of the angle at the first track boundary A with the integrated value S _θR of the angle at the second track boundary B, and specifies the second track boundary B as the track boundary having a small roughness.

In addition, the control device 180 replaces the above equations (1) and (2) with the square of the angle formed at the runway boundary of the adjacent sections as shown by the following equations (3) and (4). The sum may be used to calculate the roughness of the first track boundary and the roughness of the second track boundary.

ただし、上記式（３）及び式（４）において、ｉ、Ｓ_θＬ、Δθ_Ｌｉ、Ｓ_θＲ、及びΔθ_Ｒｉは上記式（１）及び上記式（２）と同じため、説明については適宜援用する。

However, in the above formulas (3) and _{(4), i, S θL} , Δθ Li, S θR, and [Delta] [theta] _Ri same for the above formula (1) and the equation (2), for a description incorporated appropriately ..

Returning to FIG. 1 again, the functions realized by the control device 180 will be described. The control device 180 determines whether or not offset processing needs to be performed with respect to the track center line by the offset necessity determination function. In the present embodiment, the control device 180 determines whether or not offset processing with respect to the track center line is necessary when traveling in a section where the road width is widened.

The control device 180 compares the track width with the threshold value (hereinafter, also referred to as the first threshold value), and if the track width is larger than the first threshold value, determines that offset processing is necessary with respect to the track center line. On the contrary, the control device 180 determines that the offset processing is unnecessary when the track width is equal to or less than the first threshold value. The control device 180 determines the necessity of offset processing at each point on the track center line. The first threshold value is a threshold value for determining whether or not the track width has changed in the direction of widening, and is a predetermined threshold value. The first threshold value may be an average value of the track width in a predetermined section, or may be an upper limit value of the track width set in advance according to the type of road. The average value of the track width in the predetermined section is set in advance based on, for example, map information. Further, the upper limit of the track width is set in advance so as to have a relationship proportional to the road width, for example.

Explaining the necessity of offset processing with reference to FIG. 3A, for example, the control device 180 executes comparison processing with the first threshold value for each of the track width Δd ₁ to the track width Δd ₆ . For example, when the first threshold value is the average value of the track width in the predetermined section, the control device 180 has the track width of the track center line C at the points of the track width Δd ₁ , the track width Δd ₂ , and the track width Δd _6. Since it is equal to or less than the first threshold value, it is determined that offset processing is unnecessary. Further, the control device 180 determines that offset processing is necessary for the track center line C at the points of the track width Δd ₃ to the track width Δd ₅ because the track width is larger than the first threshold value.

The control device 180 uses the target travel route generation function to generate a target travel route on which the own vehicle travels based on the comparison result of the roughness of the first track boundary and the roughness of the second track boundary. The target travel route is a target route for the own vehicle to travel. In the present embodiment, the control device 180 generates a target travel route with reference to a track boundary having a smaller roughness among the first track boundary and the second track boundary. The control device 180 executes offset processing with respect to the track center line based on the track boundary having the smaller roughness among the first track boundary and the second track boundary. The control device 180 sets the offset-processed runway center line as the target running path.

FIG. 5 is a diagram for explaining a target traveling route. Since the scene shown in FIG. 5 is the same as the scene shown in FIG. 2 (A), the description of FIG. 2 (A) is appropriately incorporated. Further, the track center line C is the same as the track center line C shown in FIG. 3 (B).

In the example of FIG. 5, first, the control device 180 identifies a point on the track center line that requires offset processing with respect to the track center line C by the offset necessity determination function described above. Next, the control device 180 calculates the offset amount and the offset direction for the points on the track center line where the offset processing is determined to be necessary. For example, the control device 180 calculates the offset amount including the offset direction by using the following equations (5) and (6).

ただし、上記式（５）において、ｊはオフセット処理が必要な走路中心線上の地点を示し、Ｏ_ｊはオフセット量を示し、Ｒ_ａは第１走路境界の粗さと第２走路境界の粗さの比率（以降、単に走路境界の粗さの比率とも称す）を示し、Δｄ_ｊはオフセット処理が必要な地点における走路幅を示し、ｄ_{ｔｈ＿ｍａｘ}は第１閾値を示す。また上記式（６）において、Ｓ_θＬは第１走路境界における角度の積算値を示し、Ｓ_θＲは第２走路境界における角度の積算値を示す。なお、上記式（６）で用いられるＳ_θＬは、上記式（１）または式（３）で用いられるＳ_θＬに対応し、上記式（６）で用いられるＳ_θＲは、上記式（２）または式（４）で用いられるＳ_θＲに対応する。

However, in the above formula (5), j represents the point of the required track center line offset process, O _j represents the offset amount, R _a is the roughness of roughness and a second lane boundary of the first lane boundary ratio (hereinafter, simply referred to as a ratio roughness of the lane boundary) indicates, [Delta] d _j denotes the track width at a point requiring offset processing, d _{Th_max} shows a first threshold value. Further, in the above equation (6), S _θL indicates the integrated value of the angle at the first track boundary, and S _θR indicates the integrated value of the angle at the second track boundary. The S _θL used in the above formula (6) corresponds to the S _θL used in the above formula (1) or the above formula (3), and the S _θR used in the above formula (6) is the above formula (2). _{Alternatively,} it corresponds to S _θR used in the equation (4).

Controller 180, the ratio R _a of a roughness of the lane boundary, by determining the positive or negative value, specifying the direction (offset direction) to offset the runway center line. When the ratio R _a of the roughness of the runway boundary is a positive value ( _Ra > 0), the control device 180 specifies the left direction as the offset direction with respect to the traveling direction of the own vehicle. On the other hand, when the ratio R _a of the roughness of the runway boundary is a negative value ( _Ra <0), the control device 180 specifies the right direction as the offset direction with respect to the traveling direction of the own vehicle.

Further, when the ratio R _a of the roughness of the runway boundary is zero ( _Ra = 0), the control device 180 determines that the offset processing is unnecessary. The offset necessity determining function, even at the point where the offset processing is determined to be necessary, the control device 180, when the ratio R _a of a roughness of the lane boundary is zero, again determines the offset processing is not required. In order to widen the track width, there are cases where the track boundary on one side of the first track boundary or the second track boundary is widened, and there are cases where the track boundaries on both sides of the first track boundary and the second track boundary are widened. If one side of the lane boundary spreading, large passage width than the first threshold value, and the ratio R _a of a roughness of the lane boundary is positive or negative value. On the other hand, if both sides of the lane boundary spreading, passage width is also greater than the first threshold, because the roughness of the roughness and second lane boundary of the first lane boundary is the same, the ratio R _a of a roughness of the lane boundary May show zero. In such a case, it is based on the viewpoint that it is not necessary to offset the track center line.

The control device 180 calculates the offset amount based on the above equation (5) at the point where the offset processing is determined to be necessary. The offset amount is a parameter indicating the direction and distance for shifting the track center line with reference to the track boundary having the smaller roughness among the first track boundary and the second track boundary.

In the example of FIG. 5, the control unit 180 by executing the offset process on five points on the track center line C, and generates the track center line C ^'that is offset process. Controller 180, a track center line C ^'that is offset processing a target traveling path of the vehicle. In the example of FIG. 5, by the offset process at the point of offset processing is required on the determined track center line C, the runway center line C ^'has a shape along the traveling direction of the host vehicle in the vicinity of bus stops 1. Note that the five point offset processing shown in the example of FIG. 5 is executed corresponds to a point of the line segment b ₄ ~b ₇ shown in FIG. Further, in the example of FIG. 5, the offset processing is executed for five points, but the number of points where the offset processing is executed is not particularly limited. For example, the control device 180 executes offset processing at predetermined intervals on the track center line C, connects the offset-processed points based on a predetermined function, and generates the offset-processed track center line. You may.

The control device 180 controls the drive mechanism 170 by the travel control function to perform all or part of the travel of the own vehicle so that the own vehicle travels on the target travel route (offset-processed track center line). Executes automatic operation control that is performed automatically. For example, the control device 180 controls the operation of the drive mechanism 170 such as the engine and the brake to execute speed traveling control for traveling the own vehicle at a predetermined set speed set by the driver. In addition, automatic driving control by the driving control function is executed after complying with the traffic regulations of each country.

Next, the control process for supporting the traveling of the own vehicle will be described. FIG. 6 is a block diagram showing a flow of control processing according to the present embodiment. The travel control process described below is executed by the control device 180. Further, the travel control process described below starts when the ignition switch or the power switch is turned on, and is repeatedly executed at a predetermined cycle (for example, every 10 milliseconds) until the ignition switch or the power switch is turned off. Will be done.

Further, in the following, a scene in which the automatic driving control is input (on) by the driver will be described as an example. That is, the own vehicle travels along the traveling route.

In step S1, the control device 180 acquires information on the track boundary. The control device 180 is based on at least one of the map information stored in the map database 120, the detection result by the distance measuring sensor 140, and the image captured by the camera 150, the type of the track boundary constituting the track of the own vehicle, and the track boundary. Acquire information on the position and the shape of the track boundary. In step S1, the control device 180 acquires information on the track boundary for each of the first track boundary and the second track boundary.

In step S2, the control device 180 calculates the distance between the first track boundary and the second track boundary as the track width. For example, the control device 180 calculates the distance between the first track boundary and the second track boundary in the vehicle width direction of the own vehicle as the track width. In step S2, the control device 180 calculates the track width in a predetermined calculation target section of the track boundary. In addition, the control device 180 calculates the track width at predetermined intervals with respect to the traveling direction of the own vehicle.

In step S3, the control device 180 determines whether or not the track width calculated in step S2 is larger than the first threshold value. The first threshold value is, for example, an average value of the track width in a predetermined section, and is a predetermined value. The control device 180 executes a comparison process with the first threshold value for the track width at each point on the track calculated in step S2. If the track width is larger than the first threshold value, the process proceeds to step S4. On the other hand, when the track width is equal to or less than the first threshold value, the control device 180 ends the control process shown in FIG. In order for the control process to be completed in step S3, all the track widths calculated in step S2 must be equal to or less than the first threshold value, and the track width is the first at any point on the track. If it is determined that the threshold value is larger than one threshold value, the process proceeds to step S4.

In step S4, the control device 180 calculates the roughness of the first track boundary and the second track boundary. For example, the control device 180 divides the track boundary into a plurality of sections as shown in the example of FIG. The control device 180 calculates the angle formed at the track boundary of the adjacent sections. The control device 180, for example, uses the above equations (1) and (2) to integrate the angles formed at the track boundaries of adjacent sections. The integrated value of the angles at the first track boundary is defined as the roughness of the first track boundary. Further, the control device 180 uses the integrated value of the angles at the second track boundary as the roughness of the second track boundary.

In step S5, the control device 180 identifies a track boundary having a smaller roughness among the first track boundary and the second track boundary. For example, the control device 180 compares the integrated value of the angle at the first track boundary with the integrated value of the angle at the second track boundary. Then, the control device 180 specifies the track boundary having a small integrated value as the track boundary having a small roughness.

In step S6, the control device 180 calculates an offset amount based on the track boundary having a small roughness specified in step S5. For example, the control device 180 calculates the offset amount by using the above equations (5) and (6).

In step S7, the control device 180 generates the offset-processed track center line by executing the offset process with respect to the track center line. The control device 180 sets the offset-processed runway center line as the target travel path of the own vehicle. For example, as shown in the example of FIG. 5, the control device 180 offsets the track center line C based on the offset direction and the offset amount at each point on the track center line C, thereby offsetting the track center. Generate line C ^' . In the example of FIG. 5, the control device 180 executes the offset processing with reference to the second runway boundary B having a small roughness. As a result, it is possible to generate a target travel route based on the second track boundary B having a small roughness. Therefore, even in a section where the road width temporarily widens, the target travel route is linked to the change in the road width. It is possible to suppress the change in shape.

In step S8, the control device 180 causes the own vehicle to travel along the target traveling route generated in step S7 as vehicle control. In the example of FIG. 5, since the own vehicle V travels along the offset-processed track center line C ^' , the own vehicle V fluctuates in the vehicle width direction as compared with the case of traveling along the track center line C. Can be suppressed. When the process of step S8 is completed, the control device 180 ends the control process shown in FIG.

As described above, in the present embodiment, the control device 180 acquires the information of the track boundary indicating the boundary between the track of the own vehicle and the track other than the track, and based on the information of the track boundary, the track of the first track boundary. The roughness of the boundary is calculated, and the roughness of the track boundary is calculated for the second track boundary based on the information of the track boundary. Then, the control device 180 generates a target travel route of the own vehicle based on the result of comparing the roughness of the track boundary calculated for the first track boundary and the roughness of the track boundary calculated for the second track boundary. , Control the own vehicle based on the target driving route. As a result, when the own vehicle passes through the section where the road width is widened, it is possible to prevent the shape of the target traveling route from changing in conjunction with the change in the road width. As a result, when the own vehicle travels in the section, it is possible to suppress the wobbling of the own vehicle due to the change in the road width. In addition, since the running of the own vehicle becomes smooth, it is possible to suppress the discomfort given to the occupants of the own vehicle.

Further, in the present embodiment, the control device 180 calculates the offset amount by the ratio of the roughness of the first track boundary and the roughness of the second track boundary, and calculates the center line of the first track boundary and the second track boundary. A target traveling route is generated by offsetting by the offset amount. As a result, a target travel route is generated with reference to a track boundary with less roughness, that is, a track boundary with a small change in the direction of the own vehicle. As a result, it is possible to suppress the change in the shape of the target traveling route linked to the change in the road width before and after the section where the road width is widened.

Further, in the present embodiment, the control device 180 has a first threshold value for determining whether or not the track width, which is the distance between the first track boundary and the second track boundary, has changed in the direction in which the track width increases. If it is larger than, the own vehicle is controlled based on the target travel route. As a result, the own vehicle can be driven along the target traveling route before passing through the section where the road width is widened, and the wobbling of the own vehicle due to the widening of the road width can be suppressed.

Further, in the present embodiment, the first threshold value is the average value of the track width in the predetermined section. As a result, even if there are road types with different road widths, it is possible to suppress the wobbling of the own vehicle. For example, even if the lane width on an expressway and the lane width in an urban area are different, it is possible to suppress the wobbling of the own vehicle due to the change in the road width when the own vehicle passes through a section where the road width is widened on any road. ..

Further, in the present embodiment, the first threshold value may be an upper limit value of the runway width set in advance according to the type of road. For example, even if there are sections where the road width is widened intermittently and the vehicle travels on a road where the widening distance is different for each section, the upper limit of the road width causes an appropriate offset in each section. The process can be executed. As a result, even when traveling on a road in which the road width changes in a complicated manner, it is possible to suppress the wobbling of the own vehicle due to the change in the road width.

Further, in the present embodiment, the control device 180 calculates the angle formed by the runway boundary in the first section and the runway boundary in the second section in the target section for calculating the roughness of the runway boundary, and the above equation ( As shown in 1) or equation (2), the integrated value of the angles integrated over the target section is calculated as the roughness of the runway boundary. As a result, the roughness of the runway boundary can be calculated without performing processing that places a heavy calculation load on the control device 180, such as a function fitting process in which fitting is performed by a function including an arbitrary degree of freedom.

Further, in the present embodiment, the control device 180 calculates the angle formed by the track boundary in the first section and the track boundary in the second section in the target section for calculating the roughness of the track boundary, and the above equation ( As shown in 3) or Eq. (4), the sum of squares of the angles calculated over the target section may be calculated as the roughness of the runway boundary. Since the squared value of the angle is reflected in the roughness of the track boundary, the larger the angle formed by the track boundary of the adjacent section, the more it can be reflected in the roughness of the track boundary.

Further, in the present embodiment, the control device 180 has a track boundary with less roughness based on the difference between the track width and the first threshold value and the ratio of the roughness of the first track boundary to the roughness of the second track boundary. The target travel route is generated by calculating the offset amount based on the above and offsetting the track center line by the offset amount. As a result, a target travel route is generated with reference to a track boundary with less roughness, that is, a track boundary with a small change in the direction of the own vehicle. As a result, it is possible to suppress the change in the shape of the target traveling route in conjunction with the change in the road width before and after the section where the road width is widened.

<< Second Embodiment >>
Next, the traveling support device according to another embodiment of the present invention will be described. In the first embodiment, the present invention has been described by taking as an example a scene in which the own vehicle travels in a section where the road width is widened, but in the present embodiment, an example is a scene in which the own vehicle travels in a section where the road width is narrowed. The present invention will be described with reference to. The present embodiment is the same as the first embodiment except that the offset necessity determination function realized by the control device 180 and the target travel route generation function are different from the first embodiment, and the description thereof is incorporated. Further, in the following description, a part different from the first embodiment will be mainly described in the functions and control processing of the control device 180. For the functions for which the description is omitted, the contents described in the first embodiment are incorporated.

In the present embodiment, the control device 180 determines the necessity of offset processing with respect to the lane center line when the own vehicle travels in a section where the lane width is narrowed by the offset necessity determination function.

The control device 180 compares the track width with the threshold value (hereinafter, also referred to as a second threshold value), and if the track width is smaller than the second threshold value, determines that offset processing is necessary. On the other hand, the control device 180 determines that the offset processing is unnecessary when the track width is equal to or larger than the second threshold value. The second threshold value is a threshold value for determining whether or not the track width has changed in the narrowing direction, and is a predetermined threshold value. The second threshold value may be an average value of the track width in a predetermined section, or may be a lower limit value of the track width set in advance according to the type of road. The lower limit of the track width is set in advance so as to have a relationship proportional to the road width, for example.

Further, in the present embodiment, when the track width is smaller than the second threshold value, the control device 180 does not determine that offset processing is necessary, and further determines whether or not there is an obstacle in the vicinity of the own vehicle V. Then, the necessity of offset processing is determined. For example, the control device 180 determines whether or not there is an obstacle in the vicinity of the own vehicle V from the detection result by the distance measuring sensor 140 and / or the image captured by the camera 150. When it is determined that there is no obstacle around the own vehicle V, the control device 180 determines that offset processing with respect to the track center line is necessary.

FIG. 7 is a diagram for explaining a function realized by the control device 180 according to the second embodiment when the own vehicle travels in a section where the road width is narrowed. 7, the vehicle V is shown a scene through a temporary section road width is narrowed in the lane L _3. Figure 7 is an overhead view of the traffic lane L ₃ from above.

In the example of FIG. 7, the control device 180 acquires the information of the track boundary forming the track of the own vehicle V by the track boundary information acquisition function. The control device 180 recognizes the curb 2 (solid line) located on the left side of the track of the own vehicle V as the first track boundary A (dashed line), and also uses the position of the curb 2 as information on the first track boundary A. And get shape information. Further, the control device 180 recognizes the center line 3 (dotted line) located on the right side of the track of the own vehicle V as the second track boundary B (one-turn chain line), and also serves as the information of the second track boundary B as the center line. Acquire information on the position and shape of 3.

Further, in the example of FIG. 7, the control device 180 calculates the track width by the track width calculation function. The control device 180 calculates the track width Δd ₁ to the track width Δd ₆ , which is the distance between the first track boundary A and the second track boundary B in the vehicle width direction of the own vehicle V.

Further, in the example of FIG. 7, the control device 180 executes a comparison process with the second threshold value for each of the track width Δd ₁ to the track width Δd ₆ by the offset necessity determination function. For example, when the second threshold value is the average value of the track width in the predetermined section, the control device 180 determines the track center line at the points of the track width Δd ₁ to the track width Δd ₃ , the track width Δd ₅ , and the track width Δd _6. , It is determined that offset processing is unnecessary because the track width is equal to or greater than the second threshold value. Further, the control device 180 makes a primary determination that offset processing is required for the track center line at the point of the track width Δd ₄ because the track width is smaller than the second threshold value. Further, the control device 180 determines whether or not there is an obstacle around the own vehicle V, and if it is determined that there is an obstacle, offset processing is required for the track center line at the point where the track width Δd ₄ is present. Is determined.

Next, the target travel route generation function realized by the control device 180 according to the second embodiment will be described. In the present embodiment as well, as in the first embodiment, the control device 180 compares the roughness of the first track boundary with the roughness of the second track boundary by the target travel route generation function, and compares the roughness of the first track boundary and the first track boundary. 2 The target travel route of the own vehicle is generated based on the track boundary where the roughness is small among the track boundaries.

In the present embodiment, the offset amount and the method of calculating the offset direction are different from those in the first embodiment. In the present embodiment, the control device 180 calculates the offset amount including the offset direction by using the following equations (7) and (8).

ただし、上記式（７）において、ｊはオフセット処理が必要な地点を示し、Ｏ_ｊはオフセット量を示し、Ｒ_ｂは第１走路境界の粗さと第２走路境界の粗さの比率を示し、Δｄ_ｊはオフセット処理が必要な地点における走路幅を示し、ｄ_ｔｈ＿minは第２閾値を示す。また上記式（８）において、Ｓ_θＬは第１走路境界における角度の積算値を示し、Ｓ_θＲは第２走路境界における角度の積算値を示す。

However, in the above equation (7), j indicates a point where offset processing is required, O _j indicates an offset amount, and R _b indicates the ratio of the roughness of the first track boundary to the roughness of the second track boundary. Δd _j indicates the track width at the point where offset processing is required, and d _{th_min} indicates the second threshold value. Further, in the above equation (8), S _θL indicates the integrated value of the angle at the first track boundary, and S _θR indicates the integrated value of the angle at the second track boundary.

It should be noted that the point of specifying the direction of offsetting the track center line by determining the positive or negative value of the ratio R _b of the roughness of the track boundary is the same as that of the first embodiment. That is, when the ratio R _b of the roughness of the runway boundary is a positive value (R _b > 0), the control device 180 specifies the left direction as the offset direction with respect to the traveling direction of the own vehicle. On the other hand, when the ratio R _b of the roughness of the runway boundary is a negative value (R _b <0), the control device 180 specifies the right direction as the offset direction with respect to the traveling direction of the own vehicle. Further, the control device 180 determines that the offset processing is unnecessary when the ratio R _b of the roughness of the runway boundary is zero (R _b = 0).

FIG. 8 is a diagram for explaining a target traveling route according to the second embodiment. Since the scene shown in FIG. 8 is the same as the scene shown in FIG. 7, the description of FIG. 7 is appropriately incorporated. In FIG. 8, the track center line C is the center line of the first track boundary A and the second track boundary B generated by the control device 180. The track center line C bulges to the right with respect to the traveling direction of the own vehicle V in a section where the road width is narrowed. Further, in FIG. 8, the control device 180 compares the roughness of the first track boundary A and the roughness of the second track boundary B, and specifies the track boundary having less roughness as the second track boundary B.

In the example of FIG. 8, the control device 180 calculates the offset amount and the offset direction by using the above equations (7) and (8) at the points where the offset processing is determined to be necessary. The controller 180 by executing the offset process for three points on the track center line C, and generates the track center line C ^'that is offset process. Controller 180, a track center line C ^'that is offset processing a target traveling path of the vehicle. By offset processing at a point on the determined track center line C which offset processing is required, the runway center line C ^'has a shape along the traveling direction of the host vehicle in a section where the road width narrows. The three points where the offset processing is executed as shown in the example of FIG. 8 are examples, and the number of points where the offset processing is executed is not particularly limited.

FIG. 9 is a block diagram showing a flow of control processing according to the present embodiment. Since steps S11 and S12 correspond to steps S1 and S2 in the first embodiment (see FIG. 6), the description of these steps incorporates the description of the first embodiment.

In step S13, the control device 180 determines whether or not the track width calculated in step S12 is smaller than the second threshold value. The second threshold value is, for example, an average value of the track width in a predetermined section, and is a predetermined value. The control device 180 executes a comparison process with the second threshold value for the track width at each point on the track calculated in step S12. If the track width is larger than the second threshold value, the process proceeds to step S14. On the other hand, when the track width is equal to or larger than the second threshold value, the control device 180 ends the control process shown in FIG. In order for the control process to end in step S13, all the track widths calculated in step S12 must be equal to or greater than the second threshold value, and the track width is the first at any point on the track. If it is determined that the threshold value is smaller than the two threshold values, the process proceeds to step S14.

In step S14, the control device 180 determines whether or not there is an obstacle in the vicinity of the own vehicle. For example, the control device 180 determines the presence or absence of an obstacle based on the detection result by the distance measuring sensor 140 and / or the image captured by the camera 150. If it is determined that an obstacle exists, the process proceeds to step S15. On the other hand, when it is determined that an obstacle exists, the control device 180 ends the control process shown in FIG.

Since steps S15 and S16 correspond to steps S4 and S5 in the first embodiment, the description of these steps is incorporated by reference to the description of the first embodiment.

In step S17, the control device 180 calculates an offset amount with reference to the track boundary having a small roughness specified in step S15. For example, the control device 180 calculates the offset amount by using the above equations (7) and (8).

In step S18, the control device 180 generates the offset-processed track center line by executing the offset process with respect to the track center line. The control device 180 sets the offset-processed runway center line as the target travel path of the own vehicle. For example, as shown in the example of FIG. 8, the control device 180 is offset processed by offsetting the track center line C based on the offset direction and the offset amount calculated at each point on the track center line C. Generates the offset centerline C ^' . In the example of FIG. 8, the control device 180 executes the offset processing with reference to the second runway boundary B having a small roughness. As a result, it is possible to generate a target travel route based on the second track boundary B having a small roughness. Therefore, even in a section where the road width is temporarily narrowed, the shape of the travel route is linked to the change in the road width. Can be suppressed from changing.

Since step S19 corresponds to step S8 in the first embodiment, the description of this step is incorporated by reference to the description of the first embodiment. When the process of step S8 is completed, the control device 180 ends the control process shown in FIG.

As described above, in the present embodiment, the control device 180 is for determining whether or not the track width, which is the distance between the first track boundary and the second track boundary, has changed in the direction in which the track width is narrowed. If it is less than the second threshold value and there are no obstacles around the own vehicle, the own vehicle is controlled based on the generated target travel route. As a result, the own vehicle can be driven along the target traveling route before passing through the section where the road width is narrowed, and the wobbling of the own vehicle due to the narrowing of the road width can be suppressed. In addition, when there are no obstacles around the own vehicle, the vehicle travels on the offset-processed track center line. Therefore, for example, when the road width is narrowed due to the presence of a vehicle parked on the road, the offset-processed track center line is traveled. It is possible to prevent the vehicle from traveling along the line. In this case, the own vehicle can be driven so as to avoid an obstacle that is a parked vehicle on the road.

Further, in the present embodiment, the second threshold value is the average value of the track width in the predetermined section. As a result, even if there are road types with different road widths, it is possible to suppress the wobbling of the own vehicle. For example, even if the lane width on an expressway and the lane width in an urban area are different, it is possible to suppress the wobbling of the own vehicle due to the change in the road width when the own vehicle passes through a section where the road width is narrowed on any road. ..

In addition, in the present embodiment, the second threshold value may be a lower limit value of the runway width set in advance according to the type of road. For example, even if there are sections where the track width is narrowed intermittently and the vehicle travels on a road where the narrowing distance is different for each section, the lower limit of the track width appropriately offsets each section. The process can be executed. As a result, even when traveling on a road in which the road width changes in a complicated manner, it is possible to suppress the wobbling of the own vehicle due to the change in the road width.

Further, in the present embodiment, the control device 180 has a track boundary with less roughness based on the difference between the track width and the second threshold value and the ratio of the roughness of the first track boundary to the roughness of the second track boundary. The target travel route is generated by calculating the offset amount based on the above and offsetting the track center line by the offset amount. As a result, a target travel route is generated with reference to a track boundary with less roughness, that is, a track boundary with a small change in the direction of the own vehicle. As a result, it is possible to suppress the change in the shape of the target traveling route in conjunction with the change in the road width before and after the section where the road width is narrowed.

It should be noted that the embodiments described above are described for facilitating the understanding of the present invention, and are not described for limiting the present invention. Therefore, each element disclosed in the above embodiment is intended to include all design changes and equivalents belonging to the technical scope of the present invention.

For example, as a modification of the above-described embodiment, the control device 180 sets a target section for calculating the roughness of the track boundary. The control device 180 sets the calculation target section based on the vehicle speed of the own vehicle. For example, the control device 180 sets a target section for calculating the roughness of the track boundary based on the vehicle speed information of the own vehicle input from the vehicle speed sensor 130. For example, the control device 180 sets the calculation target section so that the calculation target section expands in proportion to the vehicle speed of the own vehicle. Since the calculation target section is set according to the vehicle speed of the own vehicle, the roughness of the runway boundary can be calculated within an appropriate range even if the vehicle speed of the own vehicle changes.

Further, the control device 180 may set a target section for calculating the roughness of the runway boundary so as to include a section in which the runway width is larger than the first threshold value. For example, the control device 180 sets the point closest to the own vehicle among the points where the track width is larger than the first threshold value as the start point of the target section. Then, the control device 180 executes a comparison process between the track width and the first threshold value at predetermined intervals from the set start point with respect to the traveling direction of the own vehicle, and searches for a point where the track width is equal to or less than the first threshold value. To do. When there is a point where the track width is equal to or less than the first threshold value, the control device 180 sets the point as the end point of the calculation target section. The control device 180 sets the section from the start point to the end point as a target section for calculating the roughness of the track boundary. Since the roughness of the track boundary is calculated for at least the section where the road width is widened, the own vehicle can be driven by the vehicle control based on the offset-processed track center line in the calculation target section. As a result, even when the section where the road width is widened is relatively long, such as a branch point on an expressway, it is possible to suppress the wobbling of the own vehicle due to the change in the road width.

FIG. 10 is a diagram for explaining a target section for calculating the roughness of the track boundary. Since the scene shown in FIG. 10 (A) is the same as the scene shown in FIG. 2 (A), the description of FIG. 2 (A) is appropriately incorporated.

In the example of FIG. 10A, the control device 180 calculates the roughness of the first track boundary A and the second track boundary B so as to include a section in which the track width of the own vehicle V is larger than the first threshold value. to set the target section _{R 1.} Vehicle V, in the target section R _1, for traveling along the offset treated runway center line, it is possible to suppress the vehicle wanders in a section where at least the road width increases. Further, since the control process is executed only in the area where the own vehicle may fluctuate due to the change in the road width, the calculation load can be reduced.

FIG. 10B shows another scene in which the own vehicle V travels in a section where the road width is widened. In the example of FIG. 10B, the control device 180 calculates the roughness of the first track boundary A and the second track boundary B so as to include a section in which the track width of the own vehicle V is larger than the first threshold value. The target section R ₂ is set.

10 (A) and 10 (B) are common in that the road width is widened, but in FIG. 10 (A), the road width is widened due to the presence of the bus stop 1, and FIG. 10 (B) is shown. in the road width widens by the lane width of the traffic lane L ₄ spreads, i.e., in FIGS. 10 (a) and 10 (B), factors that road width widens different. Regardless of the type of factor that widens the road width, it is possible to suppress the wobbling of the own vehicle due to changes in the road width.

Further, the control device 180 may set a target section for calculating the roughness of the runway boundary so as to include a section in which the runway width is smaller than the second threshold value. For example, the control device 180 sets the point closest to the own vehicle among the points where the track width is smaller than the second threshold value as the start point of the target section. Then, the control device 180 executes a comparison process between the track width and the second threshold value at predetermined intervals from the set start point with respect to the traveling direction of the own vehicle, and searches for a point where the track width becomes the second threshold value or more. To do. When there is a point where the track width is equal to or greater than the second threshold value, the control device 180 sets the point as the end point of the target section. The control device 180 sets the section from the start point to the end point as a target section for calculating the roughness of the track boundary. Since the roughness of the track boundary is calculated for at least the section where the road width is narrowed, the own vehicle can be driven by the vehicle control based on the offset-processed track center line in the calculation target section. As a result, even when the section where the road width is narrowed is relatively long, for example, the section where the width of the lane is reduced, it is possible to suppress the wobbling of the own vehicle due to the change in the road width.

FIG. 10C shows a scene in which the own vehicle V travels in a section where the road width is narrowed. Since the scene shown in FIG. 10C is the same as the scene shown in FIG. 7, the description of FIG. 7 is appropriately incorporated.

In the example of FIG. 10C, the control device 180 calculates the roughness of the first track boundary A and the second track boundary B so as to include a section in which the track width of the own vehicle V is smaller than the second threshold value. to set the target section _{R 3.} Similar to the example described with reference to the example of FIG. 10A, since the control process is executed only in the area where the own vehicle may fluctuate due to the change in the road width, the calculation load can be reduced.

Further, in the first embodiment and the second embodiment described above, the angles formed at the runway boundaries in the adjacent sections are calculated, and the integrated values of the angles integrated over the calculation target sections or the calculated values over the calculation target sections are calculated. The sum of squares of angles is calculated as the roughness of the track boundary, but the method of defining the roughness of the track boundary is not limited to this. For example, the control device 180 calculates the curvature of the runway boundary for each predetermined section in the target section for calculating the roughness of the runway boundary, and integrates over the target section as shown in the following equations (9) and (10). The integrated value of the obtained curvatures may be calculated as the roughness of the track boundary.

ただし、上記式（９）及び式（１０）において、ｉは分割された走路境界の区間の数を示す。また上記式（９）において、Ｓ_ρＬは第１走路境界における曲率の積算値を示し、ρ_Ｌｉは各区間における第１走路境界の曲率を示す。また上記式（１０）において、Ｓ_ρＲは第２走路境界における曲率の積算値を示し、ρ_Ｒｉは各区間における第２走路境界の曲率を示す。曲率を用いて走路境界の粗さを規定することで、角度を用いて走路境界の粗さを規定するよりも、走路境界の粗さをより精度よく評価できる。

However, in the above equations (9) and (10), i indicates the number of sections of the divided track boundary. In the above formula _(9), S ρL represents the integrated value of the curvature in the first lane boundary, [rho _Li denotes the curvature of the first lane boundary in each section. In the above formula _(10), S ρR indicates the integrated value of the curvature in the second lane boundary, [rho _Ri denotes the curvature of the second lane boundary in each section. By defining the roughness of the track boundary using the curvature, the roughness of the track boundary can be evaluated more accurately than by defining the roughness of the track boundary using the angle.

Further, as shown in the following equations (11) and (12), the control device 180 may calculate the sum of squares of the curvatures calculated over a predetermined section as the roughness of the track boundary.

ただし、上記式（１１）及び式（１２）において、ｉ、Ｓ_ρＬ、ρ_Ｌｉ、Ｓ_ρＲ、及びρ_Ｒｉは上記式（９）及び上記式（１０）と同じため、説明については適宜援用する。走路境界の粗さには、曲率の二乗値が反映されるため、各区間における走路境界の曲率が大きいほど、より走路境界の粗さに反映させることができる。

However, in the above formulas (11) and (12), i, S _ρL , ρ _Li , S _ρR , and ρ _Ri are the same as the above formulas (9) and (10), so the description will be appropriately incorporated. .. Since the squared value of the curvature is reflected in the roughness of the track boundary, the larger the curvature of the track boundary in each section, the more it can be reflected in the roughness of the track boundary.

Further, in the first embodiment described above, a scene in which the own vehicle travels in a section where the road width is widened is taken as an example, and in the second embodiment described above, a scene in which the own vehicle travels in a section where the road width is narrowed is taken as an example. As mentioned above, the control device 180 may simultaneously execute the traveling support method in the first embodiment and the traveling support method in the second embodiment. That is, the control device 180 executes a comparison process with the first threshold value and the second threshold value with respect to the track width, and is a travel support method when traveling in a section where the road width is widened according to the size of the track width. , Or any of the driving support methods when traveling in a section where the road width is narrowed may be executed. As a result, it is possible to suppress the wobbling of the own vehicle due to the change of the road width when the own vehicle travels in the section where the road width changes without being limited to the direction of the change of the road width. For example, even when the own vehicle travels in a section where the road width repeatedly increases and decreases, it is possible to suppress the wobbling of the own vehicle due to the change in the road width.

100 ... Driving support device 110 ... Own vehicle position detection device 120 ... Map database 130 ... Vehicle speed sensor 140 ... Distance measurement sensor 150 ... Camera 160 ... Input device 170 ... Drive mechanism 180 ... Control device

Claims (18)

It is a driving support method for vehicles that is executed by a processor.
Acquire information on the track boundary indicating the boundary between the track of the own vehicle and the track other than the track.
Based on the information on the track boundary, the roughness of the track boundary is calculated for the first track boundary, which is the track boundary on the left side with respect to the traveling direction of the own vehicle.
Based on the information on the track boundary, the roughness of the track boundary is calculated for the second track boundary, which is the track boundary on the right side with respect to the traveling direction of the own vehicle.
Based on the result of comparing the roughness of the track boundary calculated for the first track boundary and the roughness of the track boundary calculated for the second track boundary, the target travel route of the own vehicle is generated.
A traveling support method for controlling the own vehicle based on the target traveling route. The offset amount was calculated from the ratio of the roughness of the track boundary calculated for the first track boundary to the roughness of the track boundary calculated for the second track boundary.
The travel support method according to claim 1, wherein a target travel route is generated by offsetting the center line of the first track boundary and the second track boundary by the offset amount. The first or second aspect of claim 1 or 2 in which the own vehicle is controlled based on the target travel path when the track width of the track is larger than the first threshold value for determining whether or not the track width has changed in the direction in which the track width is widened. Driving support method. The traveling support method according to claim 3, wherein the first threshold value is an average value of the track width in a predetermined section. The travel support method according to claim 3, wherein the first threshold value is an upper limit value of the track width preset according to the type of road. In the target section for calculating the roughness of the track boundary, the angle formed by the track boundary in the first section and the track boundary in the second section adjacent to the first section is calculated.
The traveling support method according to any one of claims 1 to 5, wherein the integrated value of the angles integrated over the target section is calculated as the roughness of the track boundary. In the target section for calculating the roughness of the track boundary, the angle formed by the track boundary in the first section and the track boundary in the second section adjacent to the first section is calculated.
The traveling support method according to any one of claims 1 to 5, wherein the sum of squares of the angles calculated over the target section is calculated as the roughness of the track boundary. The traveling support method according to claim 6 or 7, wherein the target section is set based on the vehicle speed of the own vehicle. The run according to claim 6 or 7, wherein the target section is set so as to include a section in which the track width of the track is larger than the first threshold value for determining whether or not the track width has changed in the direction in which the track width is widened. Support method. The run according to claim 6 or 7, wherein the target section is set so that the track width of the track includes a section smaller than a second threshold value for determining whether or not the track width has changed in the direction of narrowing the track width. Support method. In the target section for calculating the roughness of the track boundary, the curvature of the track boundary is calculated for each predetermined section.
The traveling support method according to any one of claims 1 to 5, wherein the integrated value of the curvature integrated over the target section is used as the roughness of the track boundary. In the target section for calculating the roughness of the track boundary, the curvature of the track boundary is calculated for each predetermined section.
The traveling support method according to any one of claims 1 to 5, wherein the sum of squares of the curvatures calculated over the target section is calculated as the roughness of the track boundary. An offset amount based on the track boundary having less roughness based on the difference between the track width and the first threshold value and the ratio of the roughness of the first track boundary to the roughness of the second track boundary. And calculate
The travel support method according to any one of claims 3 to 5, wherein the target travel route is generated by offsetting the center line of the first track boundary and the second track boundary by the offset amount. When the track width of the track is less than the second threshold value for determining whether or not the track width has changed in the direction of narrowing, and there is no obstacle in the vicinity of the own vehicle, the target travel route. The traveling support method according to claim 1 or 2, wherein the own vehicle is controlled based on the above. The traveling support method according to claim 14, wherein the second threshold value is an average value of the track width in a predetermined section. The travel support method according to claim 14, wherein the second threshold value is a lower limit value of the track width preset according to the type of road. An offset amount based on the track boundary having a small roughness based on the difference between the track width and the second threshold value and the ratio of the roughness of the first track boundary to the roughness of the second track boundary. And calculate
The travel support method according to any one of claims 14 to 16, wherein a target travel route is generated by offsetting the center line of the first track boundary and the second track boundary by the offset amount. It is a driving support device for vehicles with a processor.
The processor
Acquire information on the track boundary indicating the boundary between the track of the own vehicle and the track other than the track.
Based on the information on the track boundary, the roughness of the track boundary is calculated for the first track boundary, which is the track boundary on the left side with respect to the traveling direction of the own vehicle.
Based on the information on the track boundary, the roughness of the track boundary is calculated for the second track boundary, which is the track boundary on the right side with respect to the traveling direction of the own vehicle.
Based on the result of comparing the roughness of the track boundary calculated for the first track boundary and the roughness of the track boundary calculated for the second track boundary, the target travel route of the own vehicle is generated.
A travel support device that controls the own vehicle based on the target travel route.

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