JP7331450B2 - VEHICLE TRIP CONTROL METHOD AND TRIP CONTROL DEVICE - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle cruise control method and a cruise control device including autonomous cruise control.

In a vehicle driving support device, a storage unit stores logical data associated with connection relationships of actual roads to be searched for routes, and IDs of data of each link that constitutes the logical data. Data is stored in the storage unit. For example, when there are three lanes, data indicating three lanes is stored as lane data. In the lane change processing routine, a route search is performed using logical data, lane change information linked to the searched route is extracted, and a lane change link is created (Patent Document 1). .

JP 2018-197758 A

However, in the conventional technology, all the data of a plurality of lanes are extracted and processed in order to create a lane change link, so there is a problem that the data processing load is large.

The problem to be solved by the present invention is to provide a vehicle cruise control method and a cruise control device that can reduce the load of data processing when lane change support control is executed.

According to the present invention, when there is a branch road on the driving route and it is necessary to change lanes in order to follow the driving route, the road on which the vehicle is traveling is limited among the roads branched at the branch road, and map information is provided. The road information of the driving road is acquired from the storage medium of the own vehicle that stores the , and the road information of the road that is not the driving road among the roads that branch off at the fork road is not acquired from the storage medium, and the autonomous steering control function is used. The above problem is solved by activating the included lane change support function and autonomously controlling the host vehicle using the acquired road information of the traveled road .

ADVANTAGE OF THE INVENTION According to this invention, when performing lane change assistance control, the load of data processing can be suppressed.

1 is a block diagram showing an embodiment of a vehicle travel control device according to the present invention; FIG. 2 is a front view showing part of the input device of FIG. 1; FIG. 2 is a block diagram of the map database and controller of FIG. 1; FIG. FIG. 2 is a diagram for explaining a travel locus and a target point when a vehicle travels from a main line to a branch lane on a branch road; FIG. 4B is a schematic diagram showing a portion of the travel trajectory and target points of FIG. 4A; 2 is a block diagram showing state transitions of the control device of FIG. 1; FIG. FIG. 2 is a flowchart (part 1) showing cruise control processing of the vehicle cruise control device according to the present invention; FIG. FIG. 2 is a flowchart (part 2) showing a cruise control process of the vehicle cruise control device according to the present invention; FIG. 3 is a flowchart (part 3) showing cruise control processing of the vehicle cruise control device according to the present invention;

FIG. 1 is a block diagram showing the configuration of a vehicle running control device 1 according to this embodiment. The vehicle cruise control device 1 of the present embodiment is also an embodiment for carrying out the vehicle cruise control method according to the present invention. As shown in FIG. 1, the vehicle travel control device 1 according to the present embodiment includes a sensor 11, a vehicle position detection device 12, a map database 13, an in-vehicle device 14, a presentation device 15, and an input device 16. , a drive control device 17 and a control device 18 . These devices are connected by, for example, a CAN (Controller Area Network) or other in-vehicle LAN in order to transmit and receive information to and from each other.

A sensor 11 detects the running state of the host vehicle. For example, the sensors 11 may include a front camera that captures the front of the vehicle, a rear camera that captures the rear of the vehicle, a front radar that detects obstacles in front of the vehicle, and a rear camera that detects obstacles behind the vehicle. Radar, side radar that detects obstacles on the left and right sides of the vehicle, vehicle speed sensor that detects the vehicle speed, touch sensor that detects whether the driver is holding the steering wheel (capacitance sensor) ) and an in-vehicle camera that captures images of the driver. As the sensor 11, one of the plurality of sensors described above may be used, or two or more types of sensors may be used in combination. The detection result of the sensor 11 is output to the control device 18 at predetermined time intervals.

The vehicle position detection device 12 is composed of a GPS unit, a gyro sensor, a vehicle speed sensor, and the like. Also, the current position of the target vehicle is detected based on the acquired position information of the target vehicle, the angle change information acquired from the gyro sensor, and the vehicle speed acquired from the vehicle speed sensor. The position information of the target vehicle detected by the own vehicle position detection device 12 is output to the control device 18 at predetermined time intervals.

The map database 13 is a memory (storage medium) that stores three-dimensional high-precision map information including position information of various facilities and specific points, and is accessible from the control device 18 . The three-dimensional high-precision map information stored in the map database 13 is three-dimensional map information based on road shapes detected when a data acquisition vehicle is driven on an actual road. and detailed and highly accurate location information such as the size of curves (e.g. curvature or radius of curvature), road junctions, junctions, toll booths, lane reduction locations, service areas/parking areas, etc. is the map information associated with .

The in-vehicle device 14 is various devices mounted in the vehicle, and operates by being operated by the driver. Such in-vehicle equipment includes steering, accelerator pedals, brake pedals, navigation devices, direction indicators, wipers, lights, horns, and other specific switches. When the vehicle-mounted device 14 is operated by the driver, the information is output to the control device 18 .

The presentation device 15 includes, for example, a display provided in a navigation device, a display incorporated in a rearview mirror, a display incorporated in a meter section, a head-up display projected on a windshield, a speaker provided in an audio device, and a vibrating body embedded. It is a device such as a seat seat device. The presentation device 15 notifies the driver of presentation information and lane change information, which will be described later, under the control of the control device 18 .

The input device 16 is, for example, a device such as a button switch that allows manual input by the driver, a touch panel arranged on the display screen, or a microphone that allows input by the driver's voice. In this embodiment, the driver can input setting information for the presentation information presented by the presentation device 15 by operating the input device 16 . FIG. 2 is a front view showing part of the input device 16 of this embodiment, and shows an example of button switches arranged on the spokes of a steering wheel or the like. The illustrated input device 16 is a button switch used when setting ON/OFF of the autonomous speed control function and the autonomous steering control function provided in the control device 18. A main switch 161, a resume/accelerate switch 162, A set/coast switch 163 , a cancel switch 164 , an inter-vehicle distance adjustment switch 165 , and a lane change support switch 166 are provided.

The main switch 161 is a switch for turning ON/OFF the power of the system that realizes the autonomous speed control function and the autonomous steering control function of the control device 18 . After turning off the operation of the autonomous speed control function, the resume/accelerate switch 162 resumes the autonomous speed control function at the set speed before it was turned off, increases the set speed, follows the preceding vehicle and stops, and then restarts. It is a switch that allows The set/coast switch 163 is a switch that starts the autonomous speed control function at the running speed or lowers the set speed. Cancel switch 164 is a switch for turning off the autonomous speed control function. The inter-vehicle distance adjustment switch 165 is a switch for setting the inter-vehicle distance to the preceding vehicle, and is a switch for selecting one from a plurality of settings such as short distance, medium distance, and long distance. The lane change support switch 166 is a switch for instructing (approving) the start of lane change when the control device 18 confirms the start of the lane change with the driver.

In addition to the group of button switches shown in FIG. 2, a direction indicator or other switches of the vehicle-mounted device 14 can also be used as the input device 16. On the other hand, it is also possible to adopt a configuration in which the driver inputs approval or permission to change lanes by turning on the switch of the direction indicator. The setting information input by the input device 16 is output to the control device 18 .

The drive control device 17 controls running of the own vehicle. For example, the drive control device 17 uses the autonomous speed control function to control the speed of the vehicle to the set speed when the vehicle runs at a set speed or to follow a preceding vehicle. If there is a vehicle, the operation of the drive mechanism (in the case of a combustion engine vehicle, the operation of the internal combustion engine, the operation of the internal combustion engine, In an electric vehicle system, it includes the operation of the driving motor, and in a hybrid vehicle, it also includes torque distribution between the internal combustion engine and the driving motor) and brake operation. In addition, the autonomous steering control function detects the lane mark of the lane in which the vehicle is traveling (hereinafter also referred to as the own lane), and adjusts the width of the own vehicle so that the own vehicle runs in the center of the own lane, for example. When performing lane-keeping control to control the driving position in the direction, when the own vehicle performs automatic lane change control such as overtaking the preceding vehicle or changing the driving direction by the lane change support function, overtaking support function, or route driving support function , the right/left turn support function controls the operation of the steering actuator in addition to the operation of the drive mechanism and the brake operation for realizing the acceleration/deceleration and the traveling speed when controlling the vehicle to turn right or left at an intersection. By doing so, the steering control of the host vehicle is executed. The drive control device 17 controls the running of the own vehicle according to instructions from the control device 18, which will be described later. Other known methods can also be used as the travel control method by the drive control device 17 .

The control device 18 includes a ROM (Read Only Memory) that stores a program for controlling the running of the vehicle, a CPU (Central Processing Unit) that executes the program stored in the ROM, and an accessible storage device. It consists of functional RAM (random access memory). In addition, as the operation circuit, instead of or together with 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 18 has a running information acquisition function for acquiring information on the running state of the own vehicle and autonomously controls the running speed and/or steering of the own vehicle by executing a program stored in the ROM with a CPU (processor). (including an autonomous speed control function that autonomously controls the running speed of the own vehicle and an autonomous steering control function that autonomously controls the steering of the own vehicle). Each function of the control device 18 will be described below.

The travel information acquisition function of the control device 18 is a function of acquiring travel information regarding the travel state of the own vehicle. For example, the control device 18 uses the driving information acquisition function to obtain image information of the outside of the vehicle captured by the front camera and the rear camera included in the sensor 11, and the detection results of the front radar, the rear radar, and the side radar. Get it as information. In addition, the control device 18 also acquires vehicle speed information of the own vehicle detected by the vehicle speed sensor included in the sensor 11 and image information of the driver's face captured by the in-vehicle camera as driving information by the driving information acquisition function.

Furthermore, the control device 18 acquires the current position information of the own vehicle from the own vehicle position detection device 12 as the traveling information by the traveling information acquisition function. In addition, the control device 18 uses the travel information acquisition function to obtain a curved road and its curve size (for example, curvature or radius of curvature), merging point, branching point, toll gate, position where the number of lanes decreases, service area (SA)/ Location information such as a parking area (PA) is acquired from the map database 13 as travel information. In addition, the control device 18 acquires operation information of the in-vehicle device 14 by the driver from the in-vehicle device 14 as travel information using the travel information acquisition function.

Here, the travel information acquisition function will be explained using FIG. FIG. 3 is a block diagram of the map database 13 and the control device 18. As shown in FIG. The control device 18 has a first memory 18a, a second memory 18b, a data acquisition section 18c, and a travel control section 18d. The first memory 18 a is a memory (storage medium) that temporarily stores data acquired from the map database 13 . The storage capacity of the first memory 18 a is smaller than the storage capacity of the map database 13 . The second memory 18b is a memory (storage medium) that temporarily stores data acquired from the first memory 18a. The storage capacity of the second memory 18b is smaller than the storage capacity of the first memory 18a.

The data acquisition unit 18c is a functional block of the travel information acquisition function. The data acquisition unit 18c saves and deletes data in the first memory 18a and the second memory 18b. The data acquisition unit 18c also acquires data necessary for autonomous control from among the data stored in the second memory 18b according to the running state of the own vehicle, and outputs the data to the running control unit 18d. The travel control unit 18d is a functional block of an autonomous travel control function.

The map database 13 stores data of specific areas such as all over Japan. The data stored in the map database 13 are used for route searches in the navigation system. Then, the data acquisition unit 18c causes the map information stored in the map database 13 to store road information within a predetermined range with respect to the current position of the vehicle in the first memory 18a. For example, the data acquisition unit 18c stores road information for a predetermined distance (for example, 2 km) from the current position of the vehicle in the first memory 18a. The vehicle information stored in the first memory 18a includes lane center lines, lane marks (white lines), speed limits, signs, and the like.

Further, the data acquisition unit 18c causes the second memory 18b to store the road information of a predetermined range with respect to the current position of the vehicle among the road information stored in the first memory 18a. For example, the data acquisition unit 18c causes the second memory 18b to store road information up to a predetermined distance (for example, 1 km) from the current position of the vehicle. When the road information for a predetermined distance ahead of the current position of the host vehicle is stored in the first memory 18a and the second memory 18b, the predetermined distance to be stored in the memory is set in the second memory 18b rather than in the first memory 18a. is shorter.

The data acquisition unit 18c acquires only road information necessary for autonomous control from among the road information stored in the second memory 18b, and outputs the road information to the travel control unit 18d. At this time, if the road on which the vehicle travels can be limited among a plurality of lanes, the data acquisition unit 18c acquires the road information of the road on which the vehicle travels from the recorded information (data) stored in the second memory 18b. , and output to the travel control unit 18d. In other words, the data acquisition unit 18c extracts the road information stored in the second memory 18b and sends the extracted road information to the travel control unit 18d when the road on which the vehicle travels can be limited among the plurality of vehicles. Output.

The data acquisition unit 18c limits the road on which the vehicle travels from a plurality of lanes based on the driver's operation and/or the travel route. For example, when the road ahead of the current position of the vehicle is bifurcated and the driver operates the turn signal to blink the left turn signal lamp, the data acquisition unit 18c detects the left side of the bifurcated road. limited to

An example will be described in which the vehicle is approaching an interchange, and a route is set such that the vehicle exits the tollgate from the expressway and heads for a general road. In such a case, if the driver operates the turn signal before the lane change section in order to head for the road that diverges from the main road (the road that exits the main road and connects to the toll gate), the vehicle will can be limited. The second memory 18b stores the road information of the main road and the road information of the bifurcated road, and the data acquisition unit 18c selects the road information of the bifurcated road due to blinking of the blinker. , and outputs the selected road information to the travel control unit 18d.

In this way, the data acquisition unit 18c can limit the road on which the vehicle travels based on the vehicle's running state, driver's steering, travel route, etc., when the road ahead of the vehicle's current position is bifurcated. , selectively acquires road information and outputs it to the travel control unit 18d. The travel control unit 18d does not receive road information on lanes unrelated to the autonomous control of the own vehicle, but inputs road information necessary for the autonomous control of the own vehicle. can be reduced.

The autonomous driving control function of the control device 18 is a function for autonomously controlling the driving of the own vehicle without depending on the driver's operation. Autonomous steering control function to control. The autonomous speed control function and the autonomous steering control function of this embodiment will be described below.

《Autonomous speed control function》
When a vehicle ahead is detected, the autonomous speed control function sets the vehicle speed set by the driver as the upper limit and controls the distance between the vehicles according to the vehicle speed while following the vehicle ahead. If no vehicle is detected, the vehicle will run at a constant speed set by the driver. The former is also called inter-vehicle control, and the latter is called constant speed control. It should be noted that, when the speed limit of the driving lane is detected by the driving information acquisition function, the speed limit sign may be automatically set to the set vehicle speed.

To activate the autonomous speed control function, the driver first operates the resume/accelerate switch 162 or the set/coast switch 163 of the input device 16 shown in FIG. 2 to input a desired running speed. For example, if the set coast switch 163 is pressed while the vehicle is traveling at 70 km/h, the current traveling speed is set as is. The set speed can be increased by pressing the switch 162 multiple times. Conversely, if the speed desired by the driver is 60 km/h, the set coast switch 163 should be pressed a plurality of times to lower the set speed. Further, the distance between the vehicles desired by the driver can be selected by operating the distance adjustment switch 165 of the input device 16 shown in FIG.

The constant speed control uses a sensor 11, such as a forward radar, to detect obstacles in front of the vehicle, and detects that there is no preceding vehicle in the lane in which the vehicle is traveling. The drive control device 17 controls the operation of drive mechanisms such as the engine and brakes while feeding back vehicle speed data from a vehicle speed sensor so as to maintain the speed.

The inter-vehicle distance control uses a sensor 11 such as a front radar for detecting obstacles in front of the own vehicle to detect the presence of a preceding vehicle (vehicle immediately in front of the own vehicle) in the lane in which the own vehicle is traveling, and the inter-vehicle distance. While detecting , the driving control device 17 feeds back the inter-vehicle distance data from the sensor 11 (front radar) so as to maintain the inter-vehicle distance set by the driver by setting the traveling speed set by the driver as the upper limit. It controls the operation of drive mechanisms such as the engine and brakes. If the preceding vehicle stops while driving under the inter-vehicle distance control, the own vehicle will stop following the preceding vehicle. , the follow-up running is started again by the vehicle-to-vehicle distance control. If the own vehicle has been stopped for more than 30 seconds, it will not start automatically even if the preceding vehicle starts moving. , the follow-up running is started again by the vehicle-to-vehicle distance control.

《Autonomous steering control function》
The autonomous steering control function is a function that executes steering control of the own vehicle by controlling the operation of the steering actuator. Lane keep function (lane width direction maintenance function) that controls the steering so that the vehicle runs in the center of the lane, for example, and assists the driver in handling the steering wheel. When a vehicle ahead that is slower than the set vehicle speed is detected, the driver is asked if he or she wants to overtake. If the driver has set a destination in the navigation device, etc., the display will ask the driver if they would like to change lanes when they arrive at the lane change point required to follow the route. , When the driver operates the consent switch, it includes a route driving support function that controls the steering and supports lane changes.

The route driving support function is a function that controls steering, vehicle speed, and blinkers so that the own vehicle travels along the travel route when the travel route to the destination is set. FIG. 4A is a diagram for explaining a travel locus and target points when a vehicle travels from a main line to a branch lane on a branch road. FIG. 4B is a schematic diagram showing part of the travel locus and target points of FIG. 4A. In FIGS. 4A and 4B, the X axis indicates the coordinate axis in the lateral direction (vehicle width direction) of the vehicle, and the Y axis indicates the coordinate axis in the traveling direction of the vehicle on the main line.

For example, the route travel support function will be described when a travel route is set such that the vehicle exits from the main line of an expressway into a branch lane at an interchange and heads for a tollgate. As shown in FIG. 4A, lane A is a branch lane that connects the main line to the tollgate. The main line includes lanes B and C, with lane C being the overtaking lane.

When a user or the like sets a destination, the control device 180 calculates a travel route to the destination. The control device 180 executes a lane keeping function and a lane changing function in order to travel according to the travel route. The control device 180 executes each function based on the information recognized by the camera image and the map information stored in the database 13 . Since the information that can be recognized from the camera image indicates the actual driving environment, if the lane mark can be recognized from the camera image, the control device 180 preferentially uses the information recognized from the camera image to autonomously control the In the branch road as shown in FIG. 4A , a dotted boundary line is drawn between the main line and the branch lane. , part of the boundary line has disappeared, and the lane mark may not be recognized from the camera image. In addition, interchanges have various shapes depending on the location, and the road shape of the branch lane is complicated, so there is a possibility that the lane mark cannot be recognized from the camera image when traveling on the branch road. The control device 180 autonomously controls the vehicle based on the map information stored in the database 13 in order to travel along the travel route in such areas where lane marks cannot be recognized.

In this embodiment, an area in which features such as lane marks and/or obstacles to be recognized for autonomous control cannot be recognized from the camera image is specified in advance as an unrecognizable area. The unrecognizable area indicates an area where the external situation of the vehicle cannot be recognized from the camera image. Information on the size and position of the unrecognizable area is stored in the map database 13 in advance. The control device 180 refers to the map database 13 and determines whether or not there is an unrecognizable area on the calculated travel route of the vehicle. If the unrecognizable area is on the travel route, the vehicle travels in the unrecognizable area. In the unrecognizable area, the information recognized from the camera image cannot be used to activate the lane keep function. Perform keep and/or lane change functions. That is, when the vehicle is not traveling in the unrecognizable area, the control device 180 autonomously controls the vehicle using the information recognized from the camera image. Instead of images, road information stored in a map database is used to autonomously control the vehicle.

When switching from autonomous control based on camera images (hereinafter also referred to as camera control) to autonomous control based on map information (hereinafter also referred to as map control), confirm that features in front of the vehicle cannot be recognized from camera images. After that, if the autonomous control is switched, the behavior of the vehicle may increase. Autonomous control of a vehicle sets a target point on the travel locus of the vehicle, and controls steering so that the position of the vehicle passes through the target point. The travel locus of the vehicle is calculated by calculation, and when camera images are used, for example, the center line of the recognized left and right lane marks is used as the travel locus (target locus) of the vehicle. Further, when map information is used, the center line of the lane included in the map information is used as the travel locus of the vehicle. The target point is set at a position away from the current position of the host vehicle by a predetermined travel time (for example, 1.25 seconds). If the deviation between the lane mark recognized by the camera image and the lane mark stored in the map information is large, the deviation of the target point is also large. Therefore, when switching the information used for autonomous control from camera control to map control after confirming that the feature cannot be recognized from the camera image, the delay in switching the autonomous control mode and/or the deviation of the target point may cause , the behavior of the vehicle may increase.

In this embodiment, the unrecognizable area is specified in advance, and when autonomous control of the vehicle is performed, the autonomous control based on the camera image is switched to the autonomous control based on the map information before the vehicle enters the unrecognizable area. ing.

In the example shown in FIG. 4A, the control device 180 identifies a predetermined area R including a branch road as an unrecognizable area. The unrecognizable area A includes at least a boundary line between the main road and the branch lane and part of the branch lane.

The control device 180 sets the lane change start point P because it is necessary to change the lane from the main lane to the branch lane at the branch road of the interchange. The lane change start point is a point at which steering control is started so that the vehicle moves in the lateral direction (vehicle width direction). When the host vehicle is traveling in lane B, control device 180 sets lane change start point P on lane B. The lane change start point P is set at a position a predetermined distance before the point O where the branch lane starts. When the host vehicle is traveling in lane B, the lane change start point P is set on lane B. Further, when the host vehicle is traveling in lane C, the lane change start points are set on lane B and on lane C, respectively. The distance from the lane change start point set on lane C to the lane change start point set on lane B is the traveling direction of the vehicle, and the branch lane starts from the lane change point set on lane B. The time is set to be longer than the distance to the point O. When the vehicle is traveling in the overtaking lane C, it is necessary to change lanes twice before traveling in the branching lane. , so that there is plenty of room for lane changes.

The control device 180 sets an intention confirmation point Q at a position a predetermined distance before the lane change start point P for confirming the intention of the user to change lanes. At the timing when the own vehicle reaches the intention confirmation point Q, the control device 180 confirms with the driver whether the lane change is to be performed or not. When the driver operates the approval switch, the data acquisition unit 18c of the control device 180 acquires the road information of lane A, which is a branch lane, and does not acquire the road information of lanes B and C. Further, when the driver operates the turn signal in the same direction as the lane change direction, the data acquisition unit 18c of the control device 180 acquires the road information of lane A, which is a branch lane, and the road information of lanes B and C. Do not get information. The timing at which the data acquisition unit 18c of the control device 180 acquires the road information of the lane A may be at the start of flashing of the winkers or after the start of flashing of the winkers. Since the blinking of the winkers starts at the timing when the host vehicle reaches the lane change start point P, the data acquisition unit 18c of the control device 180 may acquire the information of the lane A in time with the blinking of the winkers. .

On the other hand, if the driver does not operate the consent switch, or if the driver operates the turn signal in the direction opposite to the lane change direction, it is determined that the driver does not intend to change lanes, and the data acquisition unit 18c of the control device 180 , the road information for lanes B and C, which are main lanes, is acquired, and the road information for lane A is not acquired. Lane B is the same road on which the vehicle is currently traveling.

The control device 180 recognizes the lane mark from the camera image and controls the steering so that the vehicle runs near the center of the lane B by the lane keeping function. Then, when the host vehicle has reached the lane change start point P after confirming the lane change intention, the control device 180 uses the lane change support function to recognize the lane mark from the camera image, , and controls the steering so that the vehicle position passes through the target point on the travel trajectory. This causes the vehicle to move laterally such that the distance between the vehicle's current position and the right lane mark increases.

In preparation for switching from camera control to map control, the control device 180 sets a control switching point at a fork while executing camera control. The control switching point is set at, for example, the intersection of the center line between the left and right lane marks recognized from the camera image (or an extension of the center line) and the lane center line included in the map information. be done. Alternatively, if the lateral deviation between the center line of the left and right lane marks recognized from the camera image (or the extension line by extending the center line) and the center line of the lane included in the map information is less than a predetermined length. A control switching point is set at a position where The control switching point is set at a position on the center line of lane B outside the unrecognizable area. In the example of FIG. 4A, the control switching point is set at the position of the lane change start point P. In the example of FIG. When the vehicle reaches the control switching point P (lane change starting point P), the control device 180 switches from camera control to map control. After switching from camera control to map control, autonomous control of the vehicle is executed so that the vehicle runs along the center line of the lane included in the road information A, and the vehicle runs on the branch lane.

While the vehicle is traveling in the unrecognizable area or after the vehicle passes through the unrecognizable area, the control device 180 calculates the timing of switching from map control to camera control. The control device 180 calculates a target point (hereinafter also referred to as a first target point) using a camera image while traveling through the unrecognizable area or after passing through the unrecognizable area. If the lane mark cannot be stably recognized from the camera image in the unrecognizable area, the first target point is calculated after the lane mark becomes recognizable. The control device 180 also uses the road information A to calculate a target point (hereinafter also referred to as a second target point). Then, when the difference between the first target point and the second target point becomes equal to or less than a predetermined value, the control device 180 switches from map control to camera control.

As shown in FIG. 4B, the curve _CL represents the travel locus calculated from the camera image, and the curve _ML represents the travel locus calculated from the map information (road information A). A first target point C is represented by a position ( _Xc , _Yc ) and a second target point M is represented by a position ( _XM , _YM ). With the current position of the vehicle as the origin, the angle (θ _C ) formed by the line segment connecting the origin and the first target point C and the X axis is calculated. Also, with the current position of the vehicle as the origin, the angle (θ _M ) formed by the line segment connecting the origin and the second target point M and the X axis is calculated. The angles (θ _C , θ _M ) are calculated by the following equations (1) and (2).

By subtracting the angle (θ _M ) from the angle (θ _C ), the difference between the first target point and the second target point is calculated. The difference is calculated as an absolute value. Then, the calculated difference is compared with a preset threshold value (Δθ _th ). That is, the control device 180 determines whether or not the condition of the following formula (3) is satisfied.

When the absolute value of the calculated difference is equal to or less than the threshold (Δθ _th ), the control device 180 switches from map control to camera control and autonomously drives the vehicle so that the position of the vehicle passes through the first target point. Control.

In the example of FIG. 4B, the difference between the angle (θ _C1 ) calculated with respect to the first target point C ₁ and the angle (θ _M1 ) calculated with respect to the second target point M ₁ is the threshold value (Δθ _th ). Therefore, at the timing when the second target point _M1 is calculated, the control device 180 continues map control. The difference between the angle (θ _C2 ) calculated for the first target point C ₂ and the angle (θ _M2 ) calculated for the second target point M ₂ is smaller than the threshold (Δθ _th ). Therefore, when the own vehicle passes the first target point _C2 , the control device 180 switches from map control to camera control. As a result, when switching from map control to camera control, it is possible to suppress the behavior of the vehicle from increasing.

FIG. 5 is a block diagram showing state transitions of each function established in the control device 18. As shown in FIG. In the figure, the system means an autonomous driving control system realized by the control device 18. FIG. When the main switch 161 shown in FIG. 2 is turned ON from the system OFF state shown in the figure, the system enters the standby state. Autonomous speed control starts from this standby state by turning on the set/coast switch 163 or the resume/accelerate switch 162 in FIG. As a result, the above-described constant speed control or inter-vehicle distance control is started, and the driver can drive the own vehicle simply by operating the steering wheel without stepping on the accelerator or brake.

If the condition (1) in FIG. 5 is established while the autonomous speed control is being executed, the lane keeping mode of the autonomous steering control/hands-on mode is entered. This condition (1) is not particularly limited, but the lane marks on both sides of the own vehicle are detected, the driver is holding the steering wheel, the driver is driving near the center of the lane, and the turn signal is activated. wipers are not operating at high speed (HI), and if there is a high-definition map, there are no toll gates, exits, merges, intersections, or lane reduction points within about 200m ahead. For example, the establishment of a condition can be exemplified. Hands-on mode is a mode in which autonomous steering control is not activated unless the driver is holding the steering wheel, and hands-off mode is a mode in which autonomous steering control is activated even if the driver releases the steering wheel.

If the condition (2) in FIG. 5 is satisfied while the lane keeping mode of the autonomous steering control/hands-on mode is being executed, the lane keeping mode of the autonomous steering control/hands-off mode is entered. Conditions (2) include, but are not limited to, the vehicle traveling on a motorway, traveling on a road that is structurally separated from oncoming traffic, and traveling on a road with a high-precision map. the vehicle speed is below the speed limit; the GPS signal is valid; the driver is holding the steering wheel; the driver is facing forward; , There are no exits, confluences, intersections, or points where the number of lanes decreases. There are no sharp curves of 100R or less within about 500m ahead. It can be exemplified that all the conditions such as that there is no

Conversely, if the condition (3) in FIG. 5 is satisfied while the lane keeping mode of the autonomous steering control/hands-off mode is being executed, the lane keeping mode of the autonomous steering control/hands-on mode is entered. Conditions (3) include, but are not limited to, that the vehicle is traveling on a road other than a motorway, traveling on a two-way traffic section, and traveling on a road that does not have a high-precision map. , the vehicle was traveling at a speed exceeding the speed limit, the GPS signal could not be received, the driver did not turn forward within 5 seconds after the forward look warning was activated, and the driver was driving with a driver monitor camera. If there is a tollgate, exit, merging, or lane reduction approximately 800m ahead, and if the vehicle speed is less than approximately 40km/h, 100R within approximately 200m ahead If the vehicle is traveling at a speed of approximately 40km/h or more, there is a sharp curve of 170R or less within approximately 200m ahead of the vehicle, and the vehicle is traveling in a tunnel more than 500m from the tunnel entrance. For example, the driver holds the steering wheel and depresses the accelerator pedal, or the proximity alarm is activated.

If the condition (4) in FIG. 5 is satisfied while the lane keeping mode of the autonomous steering control/hands-off mode is being executed, the autonomous steering control is stopped and the transition is made to the autonomous speed control. This condition (4) is not particularly limited, but may be any of the following: lane marks on both sides of the vehicle have not been detected for a certain period of time, the driver has operated the steering wheel, or the wipers have been operated at high speed (HI). It can be exemplified that the condition of Further, when the condition (5) in FIG. 5 is satisfied while the lane keeping mode of the autonomous steering control/hands-off mode is being executed, the autonomous steering control and the autonomous speed control are stopped and the vehicle shifts to the standby state. Conditions (5) include, but are not limited to, the driver operating the brake, the driver operating the cancel switch 164 in FIG. The seat sensor detects that the driver has left the driver's seat, the selector lever is moved to a position other than "D" or "M", the parking brake is activated, the vehicle's skid prevention device is turned off. The skid prevention device has been activated. Snow mode has been turned on. The emergency brake has been activated. However, the detection of poor visibility, such as the inability to correctly recognize objects due to dirt, backlight, rain, fog, etc., the front radar detecting shielding and radio interference, the front radar detecting axis misalignment, and the side radar It can be exemplified that any one of conditions such as shielding, detection of radio interference, detection of axis deviation by the side radar, etc. is established.

If the condition (6) in FIG. 5 is satisfied while the autonomous steering control/hands-on mode is being executed, the autonomous steering control is stopped and the transition is made to the autonomous speed control. Conditions (6) include, but are not limited to, the fact that the lane marks on both sides of the vehicle are no longer detected, the driver has operated the steering wheel, the driver has operated the turn signals, and the wipers are operating at high speed (HI). or the tollgate section is reached when there is a high-definition map, or the front camera detects poor visibility that prevents objects from being correctly recognized due to dirt, backlight, rain, or fog. It can be exemplified that it is established. Further, when the condition (7) in FIG. 5 is established while the autonomous steering control/hands-on mode is being executed, the autonomous steering control and the autonomous speed control are stopped and the state is changed to the standby state. Conditions (7) include, but are not limited to, the driver operating the brake, the driver operating the cancel switch 164 shown in FIG. The seat sensor detects that the driver has left the driver's seat, the selector lever is moved to a position other than "D" or "M", the parking brake is activated, the vehicle's skid prevention device is turned off. The skid prevention device has been activated. For example, the detection of shielding, radio interference, or the detection of axial misalignment by the front radar satisfies any of the conditions.

If the condition (8) in FIG. 5 is satisfied while the autonomous speed control is being executed, the state transitions to the standby state. Conditions (8) include, but are not limited to, the driver operating the brake, the driver operating the cancel switch 164 in FIG. The seat sensor detects that the driver has left the driver's seat, the selector lever is moved to a position other than "D" or "M", the parking brake is activated, the vehicle's skid prevention device is turned off. The skid prevention device has been activated. For example, the detection of shielding, radio interference, or the detection of axial misalignment by the front radar satisfies any of the conditions.

If the condition (9) in FIG. 5 is established while the lane keep mode of the autonomous steering control/hands-off mode is being executed, the lane change mode of the autonomous steering control/hands-on mode is entered. This condition (9) is not particularly limited, but may be any condition such as the driver pressing the lane change support switch 166 in FIG. 2 or the driver operating the turn signal when the system proposes a lane change. can be exemplified.

If the condition (10) in FIG. 5 is satisfied while the lane change mode of the autonomous steering control/hands-on mode is being executed, the lane transition is made to the lane keep mode of the autonomous steering control/hands-on mode. Conditions (10) include, but are not limited to, exceeding the speed limit before starting the lane change operation (LCP), the driver holding the steering wheel and stepping on the accelerator pedal before starting the LCP, LCP could not be started within 10 seconds after pushing the lane change assistance switch 166 during the lane change proposal when there was a slow car ahead, and the lane change assistance switch was not started during the lane change proposal for traveling according to the route. After pressing 166, LCP could not be started and it was too close to the fork, the actual lane change maneuver (LCM) could not be started within 5 seconds after LCP was activated, LCP was started, The vehicle speed dropped below about 50 km/h before the LCM started. After the LCP was activated, there was no more space in the adjacent lane to change lanes before the LCM started. The driver canceled before the LCM started. It was determined that the operation was performed, that the lane mark was not detected before the start of the LCM, that there was no adjacent lane in the direction of the lane change, or that there was no adjacent lane within a certain distance ahead before the start of the LCM. Before the start of LCM, it was determined that there was a curve with a radius of curvature of 250m or less within a certain distance ahead, and before the start of LCM, the type of lane marking prohibited lane changes to the adjacent lane within a certain distance ahead. Before the LCM started, the side radar detected shielding and radio interference. Before the LCM started, the side radar detected an axis misalignment. The driver did not hold the steering wheel within about 2 seconds after it was activated, and the driver held the steering wheel within about 2 seconds after pressing the lane change assistance switch 166 during the lane change proposal when there was a slow vehicle ahead. the driver did not hold the steering wheel within about 2 seconds after pushing the lane change support switch 166 during the lane change proposal for traveling according to the route), the driver turned on the turn signal. It can be exemplified that any one of the conditions such as erasing or completion of LCP is satisfied.

If the main switch 161 is turned off in any one of the autonomous steering control/hands-off mode, the autonomous steering control/hands-on mode, the autonomous speed control, and the standby state, the system is turned off.

Next, traveling control processing according to the present embodiment will be described with reference to FIGS. 6A to 6C. 6A to 6C are flowcharts showing travel control processing according to the present embodiment. The travel control process described below is executed by the control device 18 at predetermined time intervals. In addition, in the following description, autonomous speed control and autonomous steering control are executed by the autonomous driving control function of the control device 18, and the width direction of the vehicle is controlled so that the vehicle runs within the lane at the speed set by the driver. While the lane keep control for controlling the traveling position is being performed, the interchange is approaching and the vehicle is traveling along a route that requires a lane change in order to follow the traveling route.

First, in step S1 of FIG. 6A, it is determined whether or not the main switch 161 of the control device 18 is turned on, and if the main switch 161 is turned off, step S1 is repeated until it is turned on. If the main switch 161 is ON, the process proceeds to step S2 to determine whether or not the driver has set the running speed. If the travel speed has not been set, the process returns to step S1, and steps S1 and S2 are repeated until the travel speed is set. The driving speed is set by the driver by operating the resume/accelerate switch 162 or the set/coast switch 163 of the input device 16 shown in FIG. 2 to input a desired driving speed.

Autonomous speed control is started when the traveling speed is set. In step S3, a forward radar (sensor 11) for detecting obstacles in front of the vehicle is used to detect whether or not there is a preceding vehicle in the lane in which the vehicle is traveling. If there is no preceding vehicle, the process proceeds to step S5 to perform constant speed control. As a result, the driver can drive the vehicle at a desired speed simply by operating the steering wheel without stepping on the accelerator or brake.

While the vehicle distance control in step S4 or the constant speed control in step S5 is being executed, in step S6, whether or not the above-described condition (1) for transitioning to the autonomous steering control/hands-on mode lane keep mode is established. judge. If the condition (1) is satisfied, the process proceeds to step S7, and if the condition (1) is not satisfied, the process returns to step S2.

In step S7, a front radar (sensor 11) for detecting obstacles in front of the vehicle is used to detect whether or not there is a preceding vehicle ahead of the lane in which the vehicle is traveling. If there is no preceding vehicle, the process proceeds to step S9 to perform the constant speed control/lane keep mode. Note that the autonomous control in step S8 or step S9 is control based on camera images.

While the inter-vehicle distance control/lane keep mode of step S8 or the constant speed control/lane keep mode of step S9 is being executed, it is determined whether or not the destination is set in step S10 of FIG. 6B. If the destination has not been set, the process returns to step S2 in FIG. 6A. If the destination has been set, the process proceeds to step S11 to execute route travel assistance. In the route driving support, when a lane change is required to follow the driving route, a lane change start point and an intention confirmation point for confirming the intention of the lane change are set. In step S12, the map information stored in the map database 13 is referred to, and the unauthorized area is specified on the travel route. At this time, if the lane change start point is included in the unrecognizable area, the lane change start point is reset so as to be outside the unrecognizable area. In step S13, it is determined whether or not the current position of the vehicle has reached the intention confirmation point. If the intention confirmation point has not been reached, the process returns to step S11. A display screen is displayed on the display to confirm the intention of the driver as to whether or not to proceed.

In step S14, it is determined whether or not there is an intention to change lanes. After the display is displayed, if the driver operates the approval switch, it is determined that there is an intention to change lanes, and the process proceeds to step S15, and if the approval switch is not operated, it is determined that there is no intention to change lanes. , the process proceeds to step S18.

In step S15, it is determined whether or not a lane change enable condition is satisfied. The lane change enable condition is the condition shown in FIG. 5(9). However, if the conditions of FIG. 5 (9) include that the lane mark is recognized and that there is a space in the next lane necessary for lane change, the lane set in the determination process of step S15 These conditions are excluded from the modifiable conditions. If the lane change permitting condition is satisfied, the process proceeds to step S16, and if the lane change permitting condition is not satisfied, the process proceeds to step S19.

In step S16, it is determined whether or not the current position of the vehicle has reached the lane change start point. Return to step S16. If the vehicle does not follow the travel route before reaching the lane change start point (for example, the vehicle moves to a lane adjacent to the current travel lane), the process proceeds to step S19.

In step S17, the control device 180 starts blinking the winkers. In step S18, the control device 180 acquires the road information of lane A, which is a branch lane, from among the road information stored in the second memory 18b, and proceeds to step S20. In addition, when the current position of the vehicle reaches the intention confirmation point or the lane change start point, if the information of the branch lane has already been acquired, the road information of the lane A ahead of the already acquired branch lane is acquired. do. In step S19, the control device 180 acquires the road information of lanes B and C, which are main lanes, from the road information stored in the second memory 18b, and returns to step S2 in FIG. 6A.

In step S20, the autonomous control based on the camera image is switched to the autonomous control based on the map information, and lane change assistance is performed. The lane change assistance in step S20 is performed in hands-on mode. In the autonomous control based on the map information, the target point M is calculated using the road information of the lane A, and the steering is controlled so that the vehicle passes the target point M. During the autonomous control based on the map information, the calculation of the target point M is repeated at a predetermined cycle, and the steering is controlled so that the vehicle passes through each calculated target point M.

In step S21, it is determined whether or not the lane mark can be recognized from the camera image. If the lane mark can be recognized, the process proceeds to step S22, and if the lane mark cannot be recognized, the process returns to step S20. Note that the determination timing of step S21 may be performed, for example, after a predetermined period of time has passed since the autonomous control based on the camera image was switched to the autonomous control based on the map information. The length of the predetermined time may be set to be equal to or longer than the length of time from the start of the lane change to the completion of the lane change. At step S22, target points C and M are calculated. That is, in addition to the target point M, the target point C is calculated. In step S23, angles (θ _C , θ _M ) are calculated. In step S24, the difference (|θ _C −θ _M |) between the first target point and the second target point is calculated, and the calculated difference (|θ _C −θ _M |) is equal to or less than the threshold value (Δθ _th ). It is determined whether or not. If the difference (|θ _C −θ _M |) is equal to or less than the threshold value (Δθ _th ), the autonomous control based on the map information is switched to the autonomous control based on the camera image (S29). In the example of FIG. 4A, the lane change at the branch road is completed, and while the vehicle is traveling in the branch lane, the autonomous control based on the map information is switched to the autonomous control based on the camera image.

If the difference (|θ _C −θ _M |) is greater than the threshold value (Δθ _th ), in step S26, a predetermined state in which the difference (|θ _C −θ _M |) is greater than the threshold value (Δθ _th ) is established. It is determined whether or not time (for example, 10 seconds) has elapsed. If the predetermined time (eg, 10 seconds) has not elapsed, the process returns to step S22, and if the predetermined time (eg, 10 seconds) has elapsed, the autonomous steering control is turned off and switched to steering operation by the driver. Since the control flow after step S20 is executed in the hands-on mode, when the automatic steering control is turned off in step S27, the driver is gripping the steering wheel, and the driver can perform steering operation smoothly. The difference between the first target point (target point C) and the second target point (target point M) is large when the lane mark can be recognized from the camera image during execution of autonomous control based on map information. When switching from map control to camera control in this state, the behavior of the vehicle increases. Therefore, in the present embodiment, when the state in which the difference between the first target point (target point C) and the second target point (target point M) is large continues for a predetermined time or longer, the autonomous steering control is turned off. Therefore, it is possible to prevent the behavior of the vehicle from increasing at the time of control switching.

As described above, according to the vehicle travel control device 1 and the travel control method of the present embodiment, when there is a branch road on the travel route and it is necessary to change lanes in order to travel along the travel route, Selectively acquires the road information of the road on which the vehicle travels among the roads branched from the road from the information stored in the storage medium of the vehicle, and activates the lane change support function included in the autonomous steering control function. , the vehicle is autonomously controlled using the acquired road information. As a result, the road information used for driving the vehicle can be selectively acquired when traveling on a branch road, so the load of data processing can be reduced.

Further, according to the vehicle travel control device 1 and the travel control method of the present embodiment, the road information of the road on which the vehicle travels is selectively acquired in accordance with blinking of the blinkers. As a result, the road information to be used for driving the vehicle can be selectively acquired in conjunction with the blinker, so that the load of data processing can be reduced.

Further, according to the vehicle travel control device 1 and the travel control method of the present embodiment, when a lane change is necessary to travel along the travel route, the driver is notified of whether or not to change the lane, to selectively acquire the road information of the road specified by the intention to change the lane with the , or the operation of the turn signal. As a result, the road information used for driving the vehicle can be selectively acquired, so that the load of data processing can be reduced.

Further, according to the vehicle travel control device 1 and the travel control method of the present embodiment, when a lane change is necessary to travel along the travel route, the driver is notified of whether or not to change the lane, When there is no indication of intention to change lanes, road information of the same road as the road on which the vehicle is currently traveling is selectively acquired. As a result, the road information used for driving the vehicle can be selectively acquired, so that the load of data processing can be reduced.

DESCRIPTION OF SYMBOLS 1... Travel control apparatus 11... Sensor 12... Vehicle position detection apparatus 13... Map database 14... Vehicle-mounted apparatus 15... Presentation apparatus 16... Input device 161... Main switch 162... Resume/accelerate switch 163... Set/coast switch 164... Cancel switch 165 Distance adjustment switch 166 Lane change support switch 167 Display screen 168 ON button 169 OFF button 17 Drive control device 18 Control device 18a First memory 18b Second memory 18c Data acquisition unit 18d … Travel control unit

Claims (5)

A travel control method for controlling travel of a vehicle using a processor,
Calculate the driving route to the destination of the own vehicle,
activating an autonomous speed control function for autonomously controlling the running speed of the own vehicle and an autonomous steering control function for autonomously controlling the steering of the own vehicle so that the own vehicle travels on the travel route; Autonomous control of own vehicle,
When there is a fork road on the travel route and a lane change is required to travel along the travel route, limiting the travel road of the vehicle from among the roads branched at the fork road,
acquiring road information of the traveled road from a storage medium of the own vehicle storing map information ;
not acquiring from the storage medium the road information of roads that are not the driving road among the roads branched at the fork road;
A cruise control method for autonomously controlling the host vehicle by operating a lane change support function included in the autonomous steering control function and using the acquired road information of the traveled road . When the lane change support function is activated, the blinker of the own vehicle starts blinking,
2. The travel control method according to claim 1, wherein the road information of the traveled road is selectively acquired in synchronization with blinking of the winkers. If it is necessary to change lanes in order to travel according to the driving route, notify the driver whether or not to change lanes,
3. A travel control method according to claim 1 , wherein the road information of the travel road specified by the driver's indication of intention to change lanes or operation of a turn signal is selectively acquired. If it is necessary to change lanes in order to travel according to the driving route, notify the driver whether or not to change lanes,
3. A travel control method according to claim 1, wherein, when the driver does not indicate an intention to change lanes, road information of the same road as the road on which the vehicle is currently traveling is selectively acquired. a storage medium storing map information;
A controller that controls the running of the own vehicle,
The controller is
calculating a travel route to the destination of the own vehicle;
activating an autonomous speed control function for autonomously controlling the running speed of the own vehicle and an autonomous steering control function for autonomously controlling the steering of the own vehicle so that the own vehicle travels on the travel route; Autonomous control of own vehicle,
When there is a fork road on the travel route and a lane change is required to travel along the travel route, limiting the travel road of the vehicle from among the roads branched at the fork road,
acquiring road information of the traveled road from a storage medium of the own vehicle storing map information ;
not acquiring from the storage medium the road information of roads that are not the driving road among the roads branched at the fork road;
A travel control device that activates a lane change support function included in the autonomous steering control function and autonomously controls the own vehicle using the acquired road information of the travel road .

Images