WO2016189727A1

WO2016189727A1 - Travel control device and method

Info

Publication number: WO2016189727A1
Application number: PCT/JP2015/065395
Authority: WO
Inventors: 教彰藤木
Original assignee: 日産自動車株式会社
Priority date: 2015-05-28
Filing date: 2015-05-28
Publication date: 2016-12-01

Abstract

A travel control device is provided with: a reference travel area setting unit (101) for setting a reference travel area in which it is possible for a vehicle to travel; a travel area expansion unit (102) for generating a travel area in which the reference travel area around an object to be avoided is expanded when an object to be avoided is present in the reference travel area; and a target route generation unit (103) for generating a target route that avoids the object to be avoided within the travel area generated by the travel area expansion unit (102).

Description

Travel control apparatus and method

The present invention relates to a vehicle travel control apparatus and method.

Conventionally, as a driving support device, a target route is generated using multiple types of maps (wide area map, middle area map, local map) with different recognition ranges for the purpose of suppressing the computational load required to generate the target path. Is known (see Patent Document 1).

International Publication No. 2012/014280

By the way, when generating a target route that travels while avoiding an avoidance target existing ahead of the host vehicle, depending on the relationship between the previously set travel area and the avoidance target in the travel area, The target route may not be generated unless the travel area is expanded. However, in the driving support device described in Patent Document 1, since the travel area is not expanded, the host vehicle may have to stop before the avoidance target.

The problem to be solved by the present invention is to provide a travel control device and method capable of generating a target route that travels while avoiding an avoidance target regardless of the relationship between the set travel region and the avoidance target. .

The present invention sets a reference travel region in which the host vehicle can travel, and when there is an avoidance target to be avoided in the reference travel region, generates a travel region that extends the reference travel region around the avoidance target, The above-described problem is solved by generating a target route in the travel area.

According to the present invention, since the reference travel area set prior to the generation of the target route is expanded, the avoidance target is avoided regardless of the relationship between the set travel area and the avoidance target. It is possible to generate a target route to be generated.

It is a top view which shows the hardware constitutions of the vehicle to which the traveling control apparatus and method which concern on 1st Embodiment of this invention are applied. It is a functional block diagram of the control apparatus of FIG. It is a top view for demonstrating the setting process of the reference | standard driving | running | working area | region performed by the reference | standard driving | running | working area setting part of FIG. FIG. 4 is a plan view showing a travel scene in which the line-of-sight distance from the host vehicle in FIG. 3 is L _m [m]. It is a flowchart for demonstrating the process which expands the reference | standard driving | running | working area | region performed by the driving | running | working area expansion part of FIG. FIG. 4 is a plan view illustrating a relationship among the own vehicle, the avoidance target, and the reference travel area in FIG. 3. It is a graph which shows the relationship between the speed of the own vehicle, and the distance of the own vehicle and an avoidance object. It is a graph which shows the relationship between the speed of the own vehicle which does not give a passenger | crew anxiety, and the distance of the own vehicle and an avoidance object. It is the graph which superimposed the graph of FIG. 7A and FIG. 7B. It is a top view for demonstrating the expansion process of the reference | standard driving | running | working area | region performed by the driving | running | working area expansion part of FIG. It is a top view for demonstrating the expansion process of the reference | standard driving | running | working area | region performed by the driving | running | working area expansion part of FIG. It is a flowchart for demonstrating the production | generation process of the target path | route and target speed which are performed with the control apparatus of FIG. FIG. 2 is a plan view showing a traveling scene in which the relative distance between the host vehicle of FIG. 1 and another vehicle is L ₀ [m]. It is a flowchart for demonstrating the process which expands the reference | standard driving | running | working area | region performed by the reference | standard driving | running | working area expansion part of FIG. Recognition distance from the vehicle of FIG. 1 is a plan view showing a running scene as a L ₁ [m]. It is a flowchart for demonstrating the process which expands the reference | standard driving | running | working area | region performed by the driving | running | working area expansion part of FIG. It is a top view which shows the driving | running | working scene where the 2nd avoidance object which cannot be recognized from the own vehicle of FIG. 1 exists ahead of the 1st avoidance object. FIG. 3 is a plan view for explaining processing executed by the control unit in FIG. 2 when the host vehicle in FIG. 1 travels in an overtaking prohibited lane. It is a functional block diagram of the control apparatus which concerns on 2nd Embodiment of this invention. It is a flowchart for demonstrating the production | generation process of the target path | route and target speed which are performed with the control apparatus of FIG.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. A vehicle travel control apparatus according to the following embodiment is for automatically driving or driving support a vehicle according to a target route generated by an input of a driver. In the automatic driving or driving support of the vehicle according to the present embodiment, the control is started according to the driver's input, and the vehicle is driven according to the target route without the driver's accelerator operation, brake operation, and steering wheel operation. However, when the driver's accelerator operation, brake operation, or steering wheel operation is performed, the automatic driving control or driving support control is stopped or temporarily interrupted, and various operations by the driver are given priority.

<< First Embodiment >>
FIG. 1 is a plan view showing a hardware configuration of a vehicle 1 to which a travel control device according to a first embodiment of the present invention is applied. As shown in this figure, a vehicle 1 includes a GPS (Global Positioning System) receiver 2, a navigation unit 3, a vehicle speed sensor 4, a control device 100, a power train controller 6, an engine / drive system 7, A brake controller 8, a brake unit 9, a yaw rate sensor 10, an acceleration sensor 11, a camera 12A, and a steering motor controller 13 are provided.

The GPS receiver 2 detects the absolute position coordinates (latitude / longitude) of the host vehicle and transmits a reception signal to the navigation unit 3 and the control device 100. The navigation unit 3 includes a map database 5 (see FIG. 2), an information processing device, and a display device. The map database 5 also includes road shape and slope information. In this navigation unit 3, when the destination is set by the occupant, the information processing apparatus sets a travel route from the current position to the destination and displays it on the display device. In addition, the information processing apparatus transmits travel route information to the control apparatus 100.

The vehicle speed sensor 4 measures the vehicle speed of the host vehicle and transmits a measurement signal to the control device 100. As the vehicle speed sensor 4, a rotary encoder attached to a wheel can be used. This rotary encoder measures the vehicle speed based on a pulse signal generated in proportion to the rotation speed of the wheel.

The control device 100 is an integrated circuit such as a microprocessor, and includes an A / D conversion circuit, a D / A conversion circuit, a central processing unit (CPU, Central Processing Unit), a ROM (Read Only Memory), and a RAM (Read Access Memory). ) Etc. The control device 100 processes information input from sensors such as an accelerator pedal sensor and a brake pedal sensor in accordance with a program stored in a ROM to calculate a target vehicle speed, and calculates a required driving force according to the target vehicle speed as a powertrain. While transmitting to the controller 6, the required braking force according to the target vehicle speed is transmitted to the brake controller 8. In addition, the control device 100 processes the steering angle information input from the steering angle sensor according to a program stored in the ROM to calculate a target steering angle, and supplies the steering amount corresponding to the target steering angle to the steering motor controller 13. Send.

The power train controller 6 controls the engine / drive system 7 so as to realize the required driving force transmitted from the control device 100. In addition, although the vehicle provided only with an engine (internal combustion engine) as a travel drive source was taken as an example, an electric vehicle (including a fuel cell vehicle) using only an electric motor as a travel drive source, or a combination of an engine and an electric motor. You may apply to the hybrid vehicle etc. which make it a driving source.

The brake controller 8 controls the brake unit 9 provided on the wheel so as to realize the required braking force transmitted from the control device 100. The steering motor controller 13 controls a steering motor (not shown) of the steering mechanism so as to realize the target steering angle transmitted from the control device 100. This steering motor is a steering actuator attached to the column shaft of the steering.

The yaw rate sensor 10 measures the yaw rate of the host vehicle and outputs a measurement signal to the control device 100. The acceleration sensor 11 measures the acceleration of the host vehicle and outputs a measurement signal to the control device 100.

The camera 12A is an image pickup apparatus including an image pickup device such as a CCD, and is installed in the front part of the host vehicle, and images the front of the host vehicle and acquires image data. The external information recognizing unit 12 (see FIG. 2), which will be described later, moves from the image data acquired by the camera 12A to the position of an “avoidance target” such as another vehicle or curb in front of the host vehicle, or to move the other vehicle or the like. The speed or the like of “avoidance target” is calculated by image processing and is output to the control device 100.

Note that the external information recognition unit 12 of the present embodiment may include a radar device instead of the camera 12A. In this case, as the radar apparatus, a known system such as a laser range finder, a millimeter wave radar, a laser radar, or an ultrasonic radar can be used.

The “avoidance target” in the present embodiment is an object that the host vehicle should travel while avoiding itself (so as not to approach too much). The external information recognition unit 12 detects an object present in a reference travel area described later and outputs it to the control device 100.

“The avoidance target” in this embodiment includes a stationary object and a moving object. Stationary objects include other vehicles that are obstacles to vehicle travel, such as other vehicles parked and stopped, road installations such as signs and power poles, road objects such as fallen objects and snow removed, and stationary people. included. Examples of moving objects include other vehicles running at low speed and people walking. Other vehicles include motorcycles such as bicycles and motorcycles, large vehicles such as buses and trucks, special vehicles such as trailers and crane vehicles, emergency vehicles such as ambulances, fire engines, and police cars, and ordinary vehicles. Further, the avoidance targets include objects that the host vehicle should avoid, such as a construction site, a damaged area of a road surface, and a puddle, although there is no object.

FIG. 2 is a functional block diagram of the control device 100. As shown in this figure, the control device 100 includes a reference travel area setting unit 101, a travel area expansion unit 102, and a target route target speed generation unit 103. The control device 100 executes each function in cooperation with software for realizing these functions and the hardware described above.

The reference travel area setting unit 101 inputs travel route information from the navigation unit 3, inputs map information from the map database 5, and inputs absolute position information of the host vehicle from the GPS receiver 2. The travel area expanding unit 102 inputs the absolute position information of the host vehicle from the GPS receiver 2, inputs the vehicle speed information of the host vehicle from the vehicle speed sensor 4, inputs the yaw rate information of the host vehicle from the yaw rate sensor 10, and receives the acceleration sensor. 11, acceleration information of the host vehicle is input, and information such as the position and speed of an “avoidance target” such as another vehicle in front of the host vehicle is input from the external information recognition unit 12. In addition, the travel area expanding unit 102 inputs information on the reference travel area from the reference travel area setting unit 101.

Based on the travel route information, the map information, and the absolute position information of the host vehicle, the reference travel region setting unit 101 sets a reference travel region (hereinafter referred to as a reference travel region) that is determined regardless of whether or not there is an avoidance target. To do. The left and right (both sides in the width direction) boundaries of the reference travel area are stored in the map information as coordinate point sequences (f _l (k), f _r (k) k = 1, 2, ... n). The area setting unit 101 extracts a point sequence from the current position of the host vehicle to a predetermined distance from the map information and sets it to the left and right boundaries of the reference travel area.

Here, as shown in FIG. 3, the left and right boundaries f _l (k) and f _r (k) of the reference travel area are curbs and white lines (the distance between the own lane and the opposite lane) extending along the travel route of the own vehicle. This is a point sequence of coordinates such as (boundary line). The predetermined distance may be set sufficiently long, for example, a distance that can travel for several seconds at a speed limit. In this case, the speed limit for each part of the travel route is stored in the map information, and the speed limit around the current value of the host vehicle may be searched from the map information.

As described above, the left and right boundaries f _l (k) and f _r (k) of the reference travel area may be extracted from the map information stored in advance, but the camera 12A, laser range finder, etc. You may set based on the result which the apparatus of recognized.

When the avoidance target exists in the reference travel area in front of the host vehicle, the travel area expanding unit 102 generates the travel area by expanding the width of the reference travel area around the avoidance target. Here, the travel area expanding unit 102 determines the expansion amount and the expansion method of the reference travel area according to the travel scene. As an example of the driving scene, as shown in FIG. 4, the road becomes a curve at the tip of the avoidance target existing in front of the host vehicle, and there is an obstacle such as a building or a wall on the right road side. There is a scene in which the distance to the driver of the host vehicle becomes a blind spot, and as a result, the distance through which the oncoming lane can be seen is L _m [m]. Hereinafter, the process of extending the reference travel area will be described using such a scene as an example.

FIG. 5 is a flowchart for explaining the process of extending the reference travel area. First, the travel area expanding unit 102 calculates a line-of-sight distance L _m [m] (step S101). As shown in FIG. 4, the line-of-sight distance L _m [m] is a distance from the own vehicle to the intersection of the tangent and the curb when a tangent is drawn from the own vehicle to the curb on the inner circumference side of the curve. Should be calculated. The line-of-sight distance L _m [m] may be obtained with reference to map information, or may be obtained based on the result recognized by a device such as the camera 12A or the laser range finder.

Next, the traveling area expansion unit 102 relates the speed V _t [m / s] of the host vehicle according to the line-of-sight distance L _m [m] and the distance l _d [m] between the avoidance target and the host vehicle. Is calculated (step S102). In this step, if it is assumed that there is another vehicle on the opposite lane ahead of the curve where the blind spot is present, and this other vehicle has traveled from the front position by the line-of-sight distance L _m [m], The above V _t [m / s] and the distance l _d can be maintained so that the host vehicle and the other vehicle can maintain a safe distance before the vehicle avoids the side to be avoided and returns to the host lane. Calculate the relationship with [m].

Therefore, first, the travel amount l [m] in the lateral direction of the host vehicle shown in FIG. 6, the predetermined lateral acceleration a _y [m / s ² ], and the time t required to travel in the lateral direction by l [m]. The relationship with [s] is as shown in the following equation (1). The predetermined lateral acceleration a _y [m / s ² ] may be set to such an extent that the occupant does not feel uncomfortable.

Travel distance L [m] when traveling along the own lane while moving at the speed V _t [m / s] for time t [s] and moving in the lateral direction with acceleration a _y [m / s ² ] l [m] ] Is represented by the following formula (2) when the above formula (1) is used.

Here, when the own vehicle protrudes from the opposite lane by avoiding the avoidance target whose length in the traveling direction is L _vl and returns to the own lane, the own vehicle travels for the travel distance 2L + L _vl during that time. (See FIG. 8). Therefore, when an oncoming vehicle travels at a speed V _m (the speed limit of the opposite lane) from a position ahead of the vehicle by a line-of-sight distance L _m [m] (hereinafter simply referred to as the position of the line-of-sight distance L _m [m]). In order for the own vehicle to return to the own lane without interfering with other vehicles in the oncoming lane, the following inequality (3) may be satisfied.

Here, the (2), (3) from the relationship between the lateral movement amount l and the speed V _t is represented by the following equation (4).

As shown in FIG. 6 and FIG. 8, when the host vehicle is traveling in the center of the host lane (hereinafter, unless otherwise specified, the host vehicle basically operates in the center of the reference driving region and the expanded reference driving region. shall be controlled so as to run), the distance l _d between the own right end and avoidance of the right end of the vehicle when the vehicle passes through the side of the avoidance is the width of the own lane d _r, avoidance When the distance between the right end of the object and the own lane boundary line is d and the width of the own vehicle is W, the following expression (5) is given.

FIG. 7A shows the distance l _d [m] between the right end of the own vehicle and the right end of the avoidance target when the own vehicle passes the side of the avoidance target, and the speed V _t [m / s] of the own vehicle. It is a graph which shows the relationship with]. A range filled with gray in the graph is a range satisfying the above-described expression (4). Therefore, by setting the target value of the speed V _t [m / s] and the distance l _d [m] in the range in which filled in the gray speed from the position of the sight distance _{_{L m [m] V m [}} m When another vehicle in the oncoming lane travels at / s], the own vehicle can return to the own lane while avoiding the avoidance target without interfering with the other vehicle on the oncoming lane.

Next, the travel area expanding unit 102 gives anxiety to the relationship between the speed V _t [m / s] and the distance l _d [m] corresponding to the line-of-sight distance L _m [m] set in step S102. The relationship between the non-speed V _t [m / s] and the distance l _d [m] is compared (step S103). As shown in FIG. 7B, the relationship between the speed V _t [m / s] of the host vehicle that does not cause unease to the occupant and the distance l _d [m] between the right end of the avoidance target and the right end of the host vehicle is The larger the distance is, the larger the distance ld is, and the occupant cannot generally wipe away the feeling of anxiety unless the vehicle is separated from the avoidance target. Therefore, the distance l _d [m] is proportional to the speed V _t [m / s]. ] Is set to increase. Here, the slope of the increase in the distance l _d [m] with respect to the increase in the velocity V _t [m / s] is evaluated by conducting an experiment in advance and stored in the control database as a control map. Then, as shown in FIG. 7C, the travel area expanding unit 102 superimposes the graph of FIG. 7A and the graph of FIG. 7B, and the speed V _t [m / s] and the distance l _d [m] at the intersection of both graphs. Are set to the target vehicle speed V _t ′ [m / s] and the target distance l _d ′ [m] when the host vehicle passes the side to be avoided.

Next, the travel area extending unit 102 calculates the extension amount of the reference travel area so as to realize the target distance l _d ′ [m] calculated in step S103 (step S104). As shown in FIG. 8, the left boundary f _l (k) of the reference travel area is expanded so that the avoidance target is not included in the travel area. Also, right boundary f _r of the reference drive area (k) is extended to an offset from the left boundary f _l (k) by a distance d _r. The length of the traveling direction that offsets the right boundary f _r (k) is (2L + L _vl ) / 2 before and after the traveling direction around the center position of the traveling direction of the avoidance target, for a total distance of 2L + L _vl And

Here, as the sight distance L _m [m] increases, the other vehicle from emerging from the region can not be recognized in Fig. 4 (position of the sight distance L _{m [m]),} until the pass each other and said other vehicle and the host vehicle The time will be longer. For this reason, the longer the line-of-sight distance L _m [m], the more the own vehicle has a margin for avoidance, that is, the longer the distance l _d [m] between the own vehicle and the avoidance target and the speed V _t [m / Even if s] is lowered, it can be avoided. Therefore, the travel area extending unit 102 increases the distance l _d [m] between the host vehicle and the avoidance target as the line-of-sight distance L _m [m] increases, that is, extends the reference travel area more greatly.

For example, when the avoidance target is likely to move like a vehicle, the travel area expanding unit 102 increases the left boundary f _l (k) of the reference travel area with a large separation distance from the avoidance target. Expand to the side that becomes. In this case, as shown in FIG. 9, if the object to be avoided is a vehicle and the direction of the vehicle is inclined to the right side with respect to the lane (the front of the vehicle faces right front), the external information recognition unit 12. The left boundary f _l (k) of the reference travel area is avoided compared to the case where the vehicle direction is parallel to the lane or inclined to the left with respect to the lane. What is necessary is just to expand greatly to the side (right side) where the separation distance from becomes large. That is, when the direction of the vehicle to be avoided is inclined to the right with respect to the lane, it is predicted that the vehicle may move to the right and the left boundary f _l (k) of the reference travel area is set to the right Furthermore, it should be expanded more greatly. Thereby, even when the vehicle suddenly moves rightward when the vehicle passes the side of the vehicle to be avoided, a safer distance between the vehicle and the vehicle can be secured.

In addition, when the external information recognition unit 12 recognizes that the avoidance target has a characteristic such as a person that cannot specify the moving direction, the traveling area expansion unit 102 determines whether the avoidance target and the lane direction are Regardless of the relationship, the left boundary f _l (k) of the reference travel area is expanded more greatly. Thereby, even when the avoidance target suddenly moves in a direction that is not predicted when the own vehicle passes the side of the avoidance target, a safer distance between the own vehicle and the avoidance target can be secured.

In addition, when the travel area expansion unit 102 determines that the own lane is an overtaking prohibited lane based on the map information or the recognition result of the external information recognition unit 12, an action to avoid the avoidance target through the expanded reference travel area If the vehicle is overtaking, the reference travel area is not expanded (prohibited).

Returning to FIG. 5, next, the travel area expanding unit 102 expands the reference travel area according to the expansion amount calculated in step S104 (step S105).

In the present embodiment, the example in which the left and right boundaries f _l (k) and f _r (k) of the reference travel area are extended to the right side to avoid the avoidance target existing on the left side of the own lane has been described. However, when the avoidance target exists on the right side of the own lane, the left and right boundaries f _l (k) and f _r (k) of the reference travel area may be extended to the left side. Further, in the present embodiment, it is assumed that the vehicle is determined to run on the left side according to road traffic regulations, but if the vehicle is determined to travel on the right side, the method of the present embodiment is used. May be applied in the opposite direction.

The target route target speed generation unit 103 generates a target route that passes through the travel region generated by the travel region extension unit 102, and sets a target speed for the target route. The generation of the target route may be performed by a well-known method, but it may be analyzed as an optimization problem, for example, and an evaluation function may be set as in, for example, the following equation (6).

Here, the first term W _u u (s) ² of the integrand on the right side of the above equation (1) is a penalty function for the curvature change rate u as an input, and the second term W _k k (s) is also the same. ² is a penalty function for the curvature k of the path as an input. L is the length of the route, and may be set sufficiently long, for example, a length that allows the vehicle to travel for several seconds at the current speed.

The path can be obtained by solving and integrating the following equation (7) that satisfies the following equation (8) and the function (9).

Here, X is a state vector, and is composed of X = (x y θ k) ^T with the coordinates (x, y) in the path, the angle θ in the traveling direction, and the curvature k as elements. In addition, P (X (s)) in the above equation (9) is a function that expresses the distance between the boundary defined by the white line, curbstone, etc. and the path, and is a constraint for preventing the path from protruding the boundary. Set as a condition. By satisfying this constraint condition and minimizing the evaluation function of the above formula (6), a smooth target route passing through the travel region can be generated.

The target route target speed generation unit 103 calculates a steering target for causing the host vehicle to follow the generated target route, and outputs it to the steering motor controller 13. Here, the calculation of the steering target may be performed by a known method such as a method using a forward gaze model. The forward gaze model is a model that assumes that the amount of operation of the driver is proportional to the forward deviation, which is a deviation from the target course at the forward gaze point, and when such a model is used, the forward deviation is 0 [m. It is only necessary to calculate a target value that enables control to converge to.

The target route target speed generation unit 103 sets a target speed V _r of the host vehicle that travels on the generated target route. For example, the target speed V _r may be set based on the following equation (10) so that the lateral acceleration and yaw rate of the host vehicle at each point on the target route are equal to or less than a threshold value.

Here, R is the radius of curvature at each point on the target path, a _ymax is the acceleration, and ω _max is the angular velocity. The target speed V _r obtained by the above equation (10) may be smoothed by applying a gradient limiter, FIR (Finite Impulse Response) filter, or the like to the target speed V _r .

FIG. 10 is a flowchart for explaining the processing of the control device 100. In the control device 100, the following steps S201 to S204 are repeated every calculation cycle.

First, the reference travel area setting unit 101 sets a reference travel area (step S201). Next, the travel area expanding unit 102 determines whether the avoidance target exists in the reference travel area (step S202). When a negative determination is made in step S202, the target route target speed generation unit 103 generates a target route that passes through the reference travel area and a target speed for the target route (step S204).

On the other hand, when an affirmative determination is made in step S202, the travel area expanding unit 102 expands the reference travel area (step S203). Note that the travel area expanding unit 102 determines that the reference lane is determined when the own lane is an overtaking prohibited lane based on the map information or the recognition result of the external information recognition unit 12 and the act of avoiding the avoidance target corresponds to the overtaking. Do not extend (prohibit) area expansion.

When the reference travel area is expanded by the travel area expansion unit 102, the target route target speed generation unit 103 sets a target route that passes through the travel region obtained by expanding the reference travel region and the target route. A target speed is generated (step S204).

Next, as shown in FIG. 11, a process for extending the reference travel area will be described taking a travel scene in which the relative distance between the host vehicle and another vehicle traveling on the opposite lane is L ₀ [m] as an example.

FIG. 12 is a flowchart for explaining a process of extending the reference travel area. First, the travel area expanding unit 102 calculates the speed V ₀ of the other vehicle on the opposite lane recognized by the external information recognition unit 12 and the relative distance L ₀ [m] between the other vehicle and the host vehicle (step S301). ). Next, the traveling area expanding unit 102 calculates the speed V _t [m / s] of the host vehicle and the distance l _d [m] between the avoidance target and the host vehicle according to the relative distance L ₀ [m]. The relationship is calculated (step S302). Here, the line-of-sight distance L _m [m] in equation (4) is replaced with the relative distance L ₀ [m], and the speed V _m in equation (4) is replaced with the speed V _{0 of the} oncoming vehicle ( by 11), the relationship between the lateral movement amount l and the speed V _t is represented.

In this step, the range painted in gray in the graph of FIG. 7A is a range that satisfies the above-described expression (11). Therefore, by setting the target value of the speed V _t and the distance l _d within this grayed out range, the oncoming vehicle at the speed V ₀ from the position in front of the relative distance of the host vehicle L ₀ [m] When the vehicle has traveled, the host vehicle can return to the host lane while avoiding the avoidance target without interfering with the oncoming vehicle in the oncoming lane.

Next, the travel area expanding unit 102 gives anxiety to the relationship between the speed V _t [m / s] and the distance l _d [m] corresponding to the relative distance L ₀ [m] set in step S302. The relationship between the non-speed V _t [m / s] and the distance l _d [m] is compared (step S303). The processing in this step is the same as that in step S103 of FIG. 5 described above. Finally, as shown in FIG. 7C, the travel area expanding unit 102 superimposes the graph of FIG. 7A and the graph of FIG. The speed V _t [m / s] and the distance l _d [m] at the intersection of both graphs are used as the target vehicle speed V _t ´ [m / s] and the target distance l _d when the host vehicle passes the side to be avoided. Set to ´ [m].

Next, the travel area extending unit 102 calculates the extension amount of the reference travel area so as to realize the target distance l _d ′ [m] calculated in step S303 (step S304). Finally, the travel area expanding unit 102 expands the reference travel area according to the expansion amount calculated in step S304 (step S305).

Here, the longer the time from when the other vehicle is recognized by the external information recognition unit 12 to when the other vehicle and the host vehicle pass each other, the longer the time is, that is, the distance between the host vehicle and the avoidance target. Even if l _d [m] is longer and the speed V _t [m / s] of the host vehicle is lower, the host vehicle can avoid the avoidance target. Therefore, the travel area expanding unit 102 increases the distance l _d [m] between the host vehicle and the avoidance target as the time becomes longer (that is, as the relative distance L ₀ [m] becomes longer), that is, as the reference travel. Extend the region more greatly.

Next, as shown in FIG. 13, the distance in which the front of the external information recognizing unit 12 can be recognized is L ₁ [m], and a traveling scene in which no other vehicle traveling in the oncoming lane exists within this recognized distance. A process for extending the reference travel area will be described with reference to FIG.

FIG. 14 is a flowchart for explaining a process of extending the reference travel area. First, the travel area extending unit 102 reads the recognition distance L ₁ [m] of the external information recognition unit 12 from the ROM (step S401). Next, the travel area expanding unit 102 determines the vehicle speed V _t [m / s] corresponding to the recognition distance L ₁ [m] of the external information recognition unit 12 and the distance l _d between the avoidance target and the host vehicle. The relationship with [m] is calculated (step S402). Here, the line-of-sight distance L _m [m] in the above equation (4) is replaced with the recognition distance L ₁ [m], and the speed V _m in the above equation (4) is used as the speed limit V for the oncoming lane in which another vehicle travels. following equation (12) by substituted on _0, the relationship between the lateral movement amount l and the speed V _t is represented.

In this step, the grayed out range in the graph of FIG. 7A is a range that satisfies the above equation (12). Therefore, by setting the target values of the speed V _t and distance l _d within the grayed out range, the other vehicle travels at the speed V ₀ from the front position by the recognition distance L ₁ [m] from the own vehicle. In this case, the host vehicle can return to the host lane while avoiding the avoidance target without interfering with other vehicles in the oncoming lane.

Next, the travel area expanding unit 102 gives anxiety to the occupant and the relationship between the speed V _t [m / s] and the distance l _d [m] corresponding to the recognition distance L ₁ [m] set in step S402. The relationship between the non-speed V _t [m / s] and the distance l _d [m] is compared (step S403). The processing in this step is the same as that in step S103 described above. Finally, as shown in FIG. 7C, the travel area expanding unit 102 superimposes the graph of FIG. 7A and the graph of FIG. The intersection speed V _t [m / s] and the distance l _d [m] are determined based on the target vehicle speed V _t ´ [m / s] and the target distance l _d ´ [m] when the host vehicle passes the side to be avoided. ] Is set.

Next, the travel area extending unit 102 calculates the extension amount of the reference travel area so as to realize the target distance l _d ′ [m] calculated in step S403 (step S404). Finally, the travel area expanding unit 102 expands the reference travel area according to the expansion amount calculated in step S404 (step S405).

Next, as shown in FIG. 15, there is a first avoidance target in front of the host vehicle, and a blind spot is hidden from the host vehicle in front of the first avoidance target, that is, behind the first avoidance target. The process of expanding the reference travel area will be described taking a travel scene in which there is a second avoidance target that cannot be recognized as an example.

In the case where the reference travel area is expanded in such a travel scene, the travel area expansion unit 102 determines the area that becomes the blind spot ahead of the avoidance target in step S104 in FIG. 5, S304 in FIG. 12, and S404 in FIG. The left boundary f _l (k) is set according to the size. Here, the travel area expanding unit 102 calculates the size of the area that becomes a blind spot according to the relative position between the first avoidance target and the host vehicle and the size of the first avoidance target, and becomes a blind spot. As the region becomes larger, the left boundary f _l (k) is greatly expanded to the side where the separation distance from the first avoidance target becomes larger.

Thereby, even if the blind spot ahead of the 1st avoidance object is large, and the 2nd avoidance object is a vehicle, and this vehicle jumps out of the blind spot at high speed, the 2nd avoidance object It becomes easy to secure a safer distance between the vehicle and the own vehicle. On the other hand, when the time required to avoid the first avoidance target and return to the own lane is shortened, the blind spot ahead of the first avoidance target is small, and other vehicles in the opposite lane are traveling It becomes easier to secure the distance between the host vehicle and the other vehicle.

Since the travel control device of the present embodiment is configured and operates as described above, the following effects can be obtained.

[1] According to the travel control device of the present embodiment, a reference travel area in which the host vehicle can travel is set, and when there is an avoidance target to be avoided in the reference travel area, a reference around the avoidance target A travel area is generated by expanding the travel area, and a target route that avoids the avoidance target is generated in the travel area. As a result, regardless of the relationship between the width of the set travel area and the position, size, etc. of the avoidance target, the host vehicle travels avoiding the avoidance target without stopping before the avoidance target. The automatic operation control or the driving support control can be performed without interruption.

[2] According to the travel control device of the present embodiment, a preset reference travel area is expanded, and thereafter, a target route for the host vehicle to travel within the obtained travel area is generated. For this reason, compared with the case where a target route that avoids the avoidance target is generated from the beginning without setting the reference travel region, the region for generating the target route is limited. It becomes easy, and the effect of shortening the time for generating the target route and reducing the calculation load for generating the target route can be obtained.

According [3] to the travel control device of the present embodiment, sight distance L _m on the opposite lane is largely extend longer reference travel region. That is, when the oncoming lane can be seen farther, by generating a travel area in which the reference travel area is greatly expanded, it is possible to generate a target route that has a greater distance from the avoidance target and can avoid the avoidance target more safely.

[4] According to the travel control device of this embodiment, the longer the time from when the other vehicle on the opposite lane is recognized by the external information recognition unit 12 until the other vehicle and the host vehicle pass each other, the longer the reference travel region is. Expand greatly. That is, the longer the distance from the host vehicle to the other vehicle in the opposite lane (the relative distance L ₀ ) is, and the longer it takes to reach the position where both vehicles pass each other, the longer the reference travel region is expanded. Thus, it is possible to generate a target route that is larger in distance to the avoidance target and that can avoid the avoidance target more safely.

[5] According to the driving control device of the present embodiment, recognizable distance L ₁ from the vehicle greatly extend the longer reference travel region by the external information recognition unit 12. That is, when the external information recognition unit 12 can recognize the oncoming lane farther, by generating a travel area that is a larger extension of the reference travel area, the distance to the avoidance target is greater and the avoidance target is safer. A target route that can be avoided can be generated.

[6] According to the travel control device of the present embodiment, the reference travel area is greatly expanded as the range of the blind spot ahead of the first avoidance target in the external information recognition unit 12 is wider. That is, the second avoidance target is more likely to pop out from the blind spot of the first avoidance target recognized by the external information recognition unit 12, thereby generating a travel area that is a larger extension of the reference travel area. It is possible to generate a target route that is larger in distance to the avoidance target and that can avoid the second avoidance target more safely.

[7] According to the travel control apparatus of the present embodiment, when the avoidance target exists on the left side of the reference travel region, the reference travel region is expanded to the right side, and when the avoidance target exists on the right side of the reference travel region. Expands the reference travel area to the left. As a result, it is necessary to overextend the reference travel area and meander the target route excessively, as in the case of extending the reference travel area to the right side to avoid the avoidance target existing on the right side of the reference travel area. Without being limited, the amount of expansion of the reference travel area and the amount of meandering of the target route can be suppressed.

[8] According to the travel control device of this embodiment, when the avoidance target is likely to move like a vehicle, the reference travel range is greatly expanded compared to the avoidance target that is not likely to move. As described above, the amount of expansion of the reference travel area is varied according to the type of the avoidance target. In particular, in the case of an avoidance target that may move, by generating a travel area that is a larger extension of the reference travel area, a target route that can be avoided more safely by avoiding the avoidance target with a greater distance to the avoidance target. Can be generated.

[9] According to the travel control device of the present embodiment, the method of extending the reference travel region is made different according to the direction of the vehicle to be avoided with respect to the traveling direction. For example, when a vehicle parked on the left side of the reference traveling area is inclined to the right with respect to the traveling direction, the vehicle is parallel to the traveling direction or inclined to the left with respect to the traveling direction. Compared to the case, the reference travel area is greatly expanded to the right. As a result, the reference travel area can be expanded corresponding to the direction in which the vehicle that is the avoidance target may move, and a target route that can increase the distance to the vehicle and avoid the vehicle more safely can be generated.

[10] According to the travel control device of the present embodiment, for example, when the lane in which the host vehicle travels is an overtaking prohibition lane, the reference travel area is not expanded. Different methods of extending the reference travel area (expansion method and amount). Accordingly, as shown in FIG. 16, when the lane in which the host vehicle is traveling is an overtaking prohibited lane, and the act of avoiding the avoidance object corresponds to the overtaking action, the own vehicle is stopped before the avoidance target or Since the vehicle follows the avoidance target, it is possible to prevent a violation of the law.

<< Second Embodiment >>
FIG. 17 is a functional block diagram of a travel control apparatus according to the second embodiment of the present invention. In addition, the same code | symbol is attached | subjected to the structure similar to 1st Embodiment, the description is used here and repeated description is abbreviate | omitted.

The travel control device of the present embodiment has a configuration in which an avoidance target selection unit 104 is added to the travel control device of the first embodiment. The avoidance target selection unit 104 inputs information on the reference travel region from the reference travel region setting unit 101 and inputs information on the recognized object from the external information recognition unit 12. Then, the avoidance target selection unit 104 determines whether to select an object recognized by the external information recognition unit 12 in the reference travel area as an avoidance target, and outputs the determination result to the travel area expansion unit 102.

Similarly to the first embodiment, the travel area extending unit 102 extends the reference travel area according to the recognition result of the object in the reference travel area by the external information recognition unit 12. At that time, the travel area expansion unit 102 first compares the coordinates of the object with the left and right boundaries f _l (k) and f _r (k) of the reference travel area, but the avoidance target selection unit 104 selects the avoidance target. This is performed only for the object that has been removed.

When the avoidance target selection unit 104 determines whether to select an object recognized in the reference travel area as an avoidance target, for example, when the speed of the object recognized in the reference travel area is equal to or less than a threshold value. May be selected as the avoidance target. Here, the speed threshold value may be set to a value at which it can be determined that the object recognized in the reference travel area is stopped, for example. Thereby, the reference travel area can be expanded to avoid only the objects that are stopped in the reference travel area. Further, the speed threshold may be set to a value at which it can be determined that the speed of the object recognized in the reference travel area is sufficiently lower than the speed of the host vehicle. As a result, the reference travel area can be expanded to avoid only an object that moves at a low speed or stops in the reference travel area.

Furthermore, when the avoidance target selection unit 104 determines whether to select an object recognized in the reference travel area as an avoidance target, for example, the width dimension of the object recognized in the reference travel area is equal to or greater than a threshold value. In some cases, the object may be selected as an avoidance target. Here, the threshold value of the width dimension of the object may be set to a value that is larger than the width of the reference travel area, for example, so that it can be determined that the host vehicle cannot pass the side of the object through the reference travel area. . As a result, the reference travel area can be expanded to avoid the object only when the vehicle cannot pass the side of the object through the reference travel area.

FIG. 18 is a flowchart for explaining the processing of the control device 100. In the control device 100, the following steps S501 to S505 are repeated every calculation cycle.

First, the reference travel area setting unit 101 sets a reference travel area (step S501). Next, the avoidance target selection unit 104 determines whether the object recognized in front of the host vehicle by the external information recognition unit 12 is an avoidance target (step S502). When an affirmative determination is made in step S502, the travel area expanding unit 102 determines whether or not an object determined as an avoidance target exists in the reference travel area (step S503). When an affirmative determination is made in step S503, the travel area expanding unit 102 expands the reference travel area (step S504). On the other hand, if a negative determination is made in steps S502 and S503, the process proceeds to step S505.

In step S505, the target route target speed generation unit 103 generates a target route in the travel area and sets a target speed for the target route. The generation of the target route and the setting of the target speed are as described in the first embodiment.

According to the travel control device of the present embodiment, it is determined based on the relative speed between the host vehicle and the object whether or not the object existing in the reference travel region corresponds to the avoidance target. Here, when the relative speed is equal to or lower than a predetermined threshold, the object is determined as an avoidance target, and when the relative speed exceeds the predetermined threshold, the object is determined as a non-evasion target. When it is determined that the object corresponds to the avoidance target, the reference travel area is expanded, and when it is determined that the object corresponds to the non-evasion target, the reference travel area expansion process is prohibited. Thereby, for example, when the object is a preceding vehicle to be followed, it is possible to prevent unnecessary avoidance of the preceding vehicle.

Further, according to the travel control device of the present embodiment, it is determined based on the width dimension of the object whether or not the object existing in the reference travel region corresponds to the avoidance target. Here, when the width dimension is equal to or greater than a predetermined threshold, the object is determined as an avoidance target, and when the width dimension is less than the predetermined threshold, the object is determined as a non-evasion target. When it is determined that the object corresponds to the avoidance target, the reference travel area is expanded, and when it is determined that the object corresponds to the non-evasion target, the reference travel area expansion process is prohibited. Thereby, for example, when the vehicle can pass through the side of the object without protruding from the reference travel area, unnecessary avoidance of the object can be prevented.

The control device 100 corresponds to a travel control device according to the present invention, the reference travel region setting unit 101 corresponds to a reference travel region setting means according to the present invention, and the travel region expansion unit 102 travels according to the present invention. The target route target speed generation unit 103 corresponds to a target route generation unit according to the present invention, the avoidance target selection unit 104 corresponds to a determination unit according to the present invention, and the external information recognition unit Reference numeral 12 corresponds to external information recognition means according to the present invention.

The embodiment described above is described for easy understanding of the present invention, and is 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.

DESCRIPTION OF SYMBOLS 100 Control apparatus 101 Reference | standard driving | running | working area setting part 102 Traveling area expansion part 103 Target route target speed production | generation part 104 Avoidance target selection part 12 External information recognition part

Claims

Reference running area setting means for setting a reference running area in which the host vehicle can run;
When there is an avoidance target to be avoided in the reference travel region, a travel region extending means for generating a travel region that extends the reference travel region around the avoidance target;
Target route generating means for generating a target route for avoiding the avoidance target in the travel region generated by the travel region extending means;
A travel control device comprising:
The travel control device according to claim 1, wherein the travel area extending means expands the reference travel area as the line-of-sight distance of the oncoming lane increases.
The travel area extending means increases the reference travel area as the time from when the other vehicle on the opposite lane is recognized by the external information recognition means provided on the own vehicle until the other vehicle and the own vehicle pass each other is longer. The travel control device according to claim 1 or 2, which is greatly expanded.
4. The travel area expanding unit according to any one of claims 1 to 3, wherein the travel area extending unit expands the reference travel area as the distance that can be recognized from the host vehicle by the external information recognition unit provided in the host vehicle increases. Travel control device.
5. The travel area extending means expands the reference travel area to a greater extent as the recognition range of the external information recognition means provided in the host vehicle is larger in the blind spot depending on the avoidance target. The travel control device according to item.
The travel area extending means expands the reference travel area to the other side in the width direction when the avoidance target is present on one side in the width direction of the reference travel area, and the avoidance target is the reference travel area. The travel control device according to any one of claims 1 to 5, wherein the reference travel region is expanded to one side in the width direction when the other side exists in the other side in the width direction.
The travel control device according to any one of claims 1 to 6, wherein the travel area extending means sets an expansion amount of the reference travel area according to the type of the avoidance target.
The travel area extending means sets an extension direction and an extension amount of the reference travel area according to a direction of the vehicle with respect to a traveling direction when the avoidance target is a vehicle. The travel control device described.
The travel control device according to any one of claims 1 to 8, wherein the travel area expanding means sets an expansion direction and an expansion amount of the reference travel area according to a type of lane in which the host vehicle travels.
A determination unit configured to determine whether an object existing in the reference traveling region corresponds to the avoidance target based on a relative speed between the host vehicle and the object;
The determination means determines the object as an avoidance target when the relative speed is equal to or less than a predetermined threshold, and determines the object as a non-avoidance target when the relative speed exceeds the predetermined threshold;
The traveling area extending means expands the reference traveling area when the determination means determines that the object corresponds to the avoidance target, and the reference when the object is determined to correspond to the non-avoidance target. The travel control device according to any one of claims 1 to 9, wherein the travel region expansion process is prohibited.
A determination unit that determines whether or not an object in which the reference travel region exists corresponds to the avoidance target based on a width dimension of the object;
The determination means determines the object as an avoidance target when the width dimension is equal to or greater than a predetermined threshold, and determines the object as a non-avoidance target when the width dimension is less than the predetermined threshold;
The travel according to any one of claims 1 to 10, wherein the travel area extending unit prohibits the process of extending the reference travel area when the determination unit determines that the object corresponds to the non-avoidance target. Control device.
A travel control method executed by a computer of a travel control device mounted on a vehicle,
Setting a reference travel area in which the host vehicle can travel;
When there is an avoidance target to be avoided in the reference travel region, generating a travel region that extends the reference travel region around the avoidance target; and
Generating a target route that avoids the avoidance target in the travel area;
A traveling control method including: