JP2021126981A - Vehicle control device - Google Patents

Abstract

To provide a vehicle control device which can stabilize a vehicle behavior immediately after switching of a drive support mode.SOLUTION: A vehicle control device, which includes a plurality of drive support modes for supporting driving of a vehicle, calculates a target travel route R of a vehicle, calculates a correction travel route based on the target travel route on a predetermined restriction condition using an evaluation function for evaluating a correction travel route, and calculates a control target value of the vehicle for allowing the vehicle to travel on the correction travel route. The vehicle control device has a plurality of evaluation functions set so as to be different for each of the plurality of drive support modes, and uses the evaluation function corresponding to the selected drive support mode, further has a transition evaluation function different from the plurality of evaluation functions for being used in change in the drive support mode, and uses a transition evaluation function instead of the evaluation function in a predetermined period after change in the drive support mode.SELECTED DRAWING: Figure 13

Description

The present invention relates to a vehicle control device, and more particularly to a vehicle control device that assists a driver in driving a vehicle.

Conventionally, a technique for calculating a vehicle traveling route based on an evaluation function including a plurality of evaluation factors has been proposed (see, for example, Patent Document 1). In the vehicle control device described in Patent Document 1, different evaluation functions are set in each of a plurality of driving support modes. That is, the weighting coefficients of the plurality of evaluation factors are set differently for each driving support mode.

Therefore, in the vehicle control device described in Patent Document 1, the evaluation function is changed by switching the driving support mode. Thereby, in Patent Document 1, the vehicle can travel on the vehicle traveling route suitable for the selected driving support mode.

Japanese Unexamined Patent Publication No. 2019-43192

However, in the vehicle control device described in Cited Document 1, if the evaluation function is changed when the driving support mode is switched, the calculated vehicle traveling route is also changed. Therefore, there is a possibility that the vehicle behavior may change suddenly immediately after the driving support mode is switched. Specifically, there was a risk that sudden steering or sudden acceleration / deceleration would be executed by automatic vehicle control. This can be offensive to the occupants.

The present invention has been made to solve such a problem, and in a vehicle control device having a plurality of driving support modes, it is possible to stabilize the vehicle behavior immediately after switching the driving support mode. The purpose is to provide the device.

In order to solve the above-mentioned problems, the present invention is a vehicle control device provided with a plurality of driving support modes for supporting the driving of the vehicle, and the vehicle control device calculates a target traveling route of the vehicle. Using the evaluation function for evaluating the corrected travel route, the corrected travel route is calculated based on the target travel route under predetermined constraint conditions, and the control target value of the vehicle for the vehicle to travel on the corrected travel route is calculated. The vehicle control device has a plurality of evaluation functions set differently for each of the plurality of driving support modes, and uses the evaluation function corresponding to the selected driving support mode. The vehicle control device further has a transient evaluation function different from a plurality of evaluation functions for use when changing the driving support mode, and the evaluation function is used in a predetermined period after the change of the driving support mode. It is characterized by using a transient evaluation function instead of.

According to the present invention configured in this way, when the driving support mode is changed, the evaluation function used for calculating the corrected traveling route is not suddenly switched in accordance with the change in the driving support mode, but is driven. The overestimation function is used instead only for a predetermined period of time after the support mode is changed. Then, after the lapse of a predetermined period, the evaluation function for the changed driving support mode is used. Therefore, in the present invention, it is possible to suppress the calculation of a corrected traveling route that abruptly changes the vehicle behavior immediately after the driving support mode is changed.

In the present invention, preferably, the transient evaluation function is set differently depending on the combination of the driving support mode before the change and the driving support mode after the change. According to the present invention configured in this way, it is possible to set an appropriate transient evaluation function that stabilizes the vehicle behavior immediately after the change of the driving support mode according to the combination of the driving support modes before and after the change. ..

In the present invention, preferably, the vehicle control device uses an evaluation function or a transient evaluation function to calculate evaluation values for a plurality of candidate-corrected travel routes, and uses the candidate-corrected travel route with the best evaluation value as the corrected travel route. calculate.

In the present invention, preferably, the evaluation function includes the sum of a plurality of evaluation factors weighted by each weighting coefficient, the weighting coefficient is set to be different depending on the driving support mode, and the transient evaluation function is a transient evaluation function. Each includes the sum of a plurality of evaluation factors weighted by the transient weighting coefficient, and the transient weighting coefficient is set according to the combination of the driving support mode before and after the change of the driving support mode.

According to the present invention configured in this way, by setting the transient weighting coefficient according to the combination of the driving support modes before and after the change, an appropriate transient that stabilizes the vehicle behavior immediately after the change of the driving support mode is performed. Evaluation function can be set.

In the present invention, preferably, the transient weighting coefficient of at least one evaluation factor is set to change from the initial value with the lapse of time in a predetermined period after the change of the driving support mode, and the changed operation after the lapse of the predetermined period. It matches the value of the weighting factor of at least one evaluation factor of the evaluation function of the support mode.

According to the present invention configured as described above, the value of the transient weighting coefficient can be gradually brought closer to the value of the weighting coefficient of the changed driving support mode in a predetermined period after the change of the driving support mode. Thereby, in the present invention, after the driving support mode is changed, the behavior of the vehicle can be smoothly approached to the vehicle behavior of the changed driving support mode.

In the present invention, preferably, the transient weighting factor is set so that the weighting of the evaluation factor regarding the lateral position of the vehicle is smaller than the weighting factor of the changed driving support mode, and / or the vehicle. It is set to increase the weighting of the evaluation factor related to the steering angular velocity.

According to the present invention configured in this way, even if the target travel path shifts laterally from the current position of the vehicle due to the change in the driving support mode, a corrected travel path that requires sudden steering. Can be suppressed from being calculated. For example, the evaluation factor related to the lateral position of the vehicle is an evaluation factor for minimizing the difference between the lateral position of the target traveling path and the corrected traveling path, and the evaluation factor related to the steering angular velocity of the vehicle is the evaluated traveling path. It is an evaluation factor for minimizing the steering angular velocity of the vehicle in.

In the present invention, preferably, the transient weighting coefficient has a smaller weighting for the evaluation factor regarding the speed of the vehicle or a weighting regarding the evaluation factor regarding the jerk in the front-rear direction of the vehicle than the weighting coefficient of the changed driving support mode. Is set to increase, or the weighting for the evaluation factor regarding the acceleration of the vehicle in the front-rear direction is increased.

According to the present invention configured in this way, even if there is a difference between the current vehicle speed of the vehicle and the target speed according to the target travel route due to the change in the driving support mode, rapid acceleration / deceleration is required. It is possible to suppress the calculation of such a corrected traveling route. For example, the evaluation factor related to the vehicle speed is an evaluation factor for minimizing the difference between the target speed on the target traveling route and the vehicle speed on the corrected traveling route, and the evaluation factor related to the jerk in the front-rear direction of the vehicle is the corrected traveling. It is an evaluation factor for minimizing the jerk in the front-rear direction of the vehicle on the route, and the evaluation factor for the acceleration in the front-rear direction of the vehicle is an evaluation for minimizing the acceleration in the front-rear direction of the vehicle 1 on the corrected traveling route. It is a factor.

According to the vehicle control device of the present invention, it is possible to stabilize the vehicle behavior immediately after switching the driving support mode.

It is a block diagram of the vehicle control device by embodiment of this invention. It is a figure which shows the detail of the driver operation part of the vehicle control device by embodiment of this invention. It is a control block diagram of the vehicle control device according to the embodiment of this invention. It is explanatory drawing of the 1st traveling path calculated by the vehicle control device by embodiment of this invention. It is explanatory drawing of the 2nd traveling path calculated by the vehicle control device by embodiment of this invention. It is explanatory drawing of the 3rd traveling path calculated by the vehicle control device by embodiment of this invention. It is explanatory drawing of the control target calculation process in the vehicle control apparatus by embodiment of this invention. It is explanatory drawing of the correction traveling path in the vehicle control device by embodiment of this invention. It is explanatory drawing of the vehicle model in the vehicle control device by embodiment of this invention. It is explanatory drawing of obstacle avoidance by correction of the target traveling path in the vehicle control device by embodiment of this invention. It is explanatory drawing which shows the relationship between the permissible upper limit value and the clearance of the passing speed between an obstacle and a vehicle at the time of avoiding an obstacle in the vehicle control device by embodiment of this invention. It is a processing flow of the driving support control in the vehicle control device according to the embodiment of this invention. It is explanatory drawing which shows the change of the correction traveling path at the time of switching of the driving support mode in the vehicle control device by embodiment of this invention. It is explanatory drawing which shows the change of the weighting coefficient of the evaluation function at the time of switching of the driving support mode in the vehicle control device by embodiment of this invention. It is explanatory drawing of the switching example of the driving support mode in the vehicle control device by embodiment of this invention.

Hereinafter, the vehicle control device according to the embodiment of the present invention will be described with reference to the accompanying drawings.
First, the configuration of the vehicle control device will be described with reference to FIGS. 1 and 2. FIG. 1A is a configuration diagram of a vehicle control device, FIG. 1B is a diagram showing details of a driver operation unit, and FIG. 2 is a control block diagram of the vehicle control device.

The vehicle control device 100 of the present embodiment is configured to provide different driving support controls to the vehicle 1 (see FIG. 3 and the like) equipped with the vehicle control device 100 in a plurality of driving support modes. The driver can select a desired driving support mode from a plurality of driving support modes.

As shown in FIG. 1A, the vehicle control device 100 is mounted on the vehicle 1, and includes a vehicle control calculation unit (ECU) 10, a plurality of sensors and switches, a plurality of control systems, and a user regarding a driving support mode. A driver operation unit 35 for inputting is provided. The plurality of sensors and switches include an in-vehicle camera 21, a millimeter-wave radar 22, and a plurality of behavior sensors (vehicle speed sensor 23, acceleration sensor 24, yaw rate sensor 25, steering angle sensor 26, accelerator sensor 27, brake) for detecting vehicle behavior. The sensor 28), the positioning system 29, and the navigation system 30 are included. Further, the plurality of control systems include an engine control system 31, a brake control system 32, and a steering control system 33.

As shown in FIG. 1B, the driver operation unit 35 is provided in the vehicle interior of the vehicle 1 so that the driver can operate it, and is a mode for selecting a desired driving support mode from a plurality of driving support modes. Functions as a setting operation unit. The driver operation unit 35 includes an ISA switch 36a for setting a speed limit mode, a TJA switch 36b for setting a preceding vehicle following mode, an ACC switch 36c for setting an automatic speed control mode, and a lane. A LAS switch 36d for setting the keep control mode is provided. Further, the driver operation unit 35 is provided with a distance setting switch 37a for setting the inter-vehicle distance in the preceding vehicle following mode and a vehicle speed setting switch 37b for setting the vehicle speed in the automatic speed control mode or the like. ..

The ECU 10 shown in FIG. 1A is composed of a computer including a processor, a memory for storing various programs, an input / output device, and the like. The ECU 10 informs the engine control system 31, the brake control system 32, and the steering control system 33 based on the driving support mode selection signal and the set vehicle speed signal received from the driver operation unit 35, and the signals received from the plurality of sensors and switches. On the other hand, each of them is configured to be able to output a request signal for appropriately operating the engine system, the braking system, and the steering system.

The in-vehicle camera 21 takes an image of the surroundings of the vehicle 1 and outputs the captured image data. The ECU 10 identifies an object (for example, a vehicle, a pedestrian, a road, a lane marking (lane boundary line, white line, yellow line), a traffic signal, a traffic sign, a stop line, an intersection, an obstacle, etc.) based on image data. do. Further, in the present embodiment, the vehicle-mounted camera 21 also includes an in-vehicle camera that captures an image of the driver who is driving the vehicle. The ECU 10 may acquire information on an object from the outside via an in-vehicle communication device by means of transportation infrastructure, vehicle-to-vehicle communication, or the like.

The millimeter-wave radar 22 is a measuring device that measures the position and speed of an object (particularly, a preceding vehicle, a parked vehicle, a pedestrian, an obstacle, etc.), and transmits radio waves (transmitted waves) toward the front of the vehicle 1. Then, the transmitted wave is reflected by the object and the reflected wave generated is received. Then, the millimeter wave radar 22 measures the distance between the vehicle 1 and the object (for example, the inter-vehicle distance) and the relative speed of the object with respect to the vehicle 1 based on the transmitted wave and the received wave. In the present embodiment, instead of the millimeter wave radar 22, a laser radar, an ultrasonic sensor, or the like may be used to measure the distance to the object and the relative speed. In addition, a plurality of sensors may be used to configure a position and speed measuring device.

The vehicle speed sensor 23 detects the absolute speed of the vehicle 1.
The acceleration sensor 24 detects the acceleration of the vehicle 1 (longitudinal acceleration in the front-rear direction, lateral acceleration in the lateral direction). The acceleration includes the acceleration side (positive) and the deceleration side (negative).
The yaw rate sensor 25 detects the yaw rate of the vehicle 1.
The steering angle sensor 26 detects the rotation angle (steering angle) of the steering wheel of the vehicle 1.
The accelerator sensor 27 detects the amount of depression of the accelerator pedal.
The brake sensor 28 detects the amount of depression of the brake pedal.

The positioning system 29 is a global positioning satellite system (GNSS) and / or a gyro system, and detects the position of the vehicle 1 (current vehicle position information). Further, the positioning system 29 may include a position information acquisition means by dead reckoning or road-to-vehicle communication (using Wi-Fi or the like).

The navigation system 30 stores the map information inside, and can provide the map information to the ECU 10. The ECU 10 identifies roads, intersections, traffic signals, buildings, and the like existing around the vehicle 1 (particularly, ahead in the traveling direction) based on the map information and the current vehicle position information. The map information may be stored in the ECU 10.

The engine control system 31 is a controller that controls the engine of the vehicle 1. When it is necessary to accelerate or decelerate the vehicle 1, the ECU 10 outputs an engine output change request signal requesting a change in the engine output to the engine control system 31.

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

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

As shown in FIG. 2, the ECU 10 is a single CPU or processor that functions as an input processing unit 10a, a peripheral target detection unit 10b, a target travel route calculation unit 10c, a driving operation determination unit 10e, and a control target calculation unit 10f. It has. In the present embodiment, a single CPU is configured to execute a plurality of the above functions, but the present invention is not limited to this, and a plurality of CPUs can be configured to execute these functions.

The input processing unit 10a is configured to process various sensor / switch groups including the vehicle-mounted camera 21 and input information input from the driver operation unit 35. The input processing unit 10a functions as an image analysis unit that analyzes the image of the camera 21 that captures the traveling road surface and detects the traveling lane (the lane markings on both sides of the lane) in which the vehicle 1 is traveling.

The peripheral target detection unit 10b is configured to detect peripheral targets based on input information from the millimeter wave radar 22, the camera 21, and the like.
The target travel route calculation unit 10c is configured to calculate the target travel route of the vehicle based on input information from the millimeter wave radar 22, the vehicle-mounted camera 21, the sensor group, and the like.

When the occupant operates the accelerator pedal, the brake pedal, or the steering wheel while the automatic speed control and / or the automatic steering control is being executed as the driving support control, the driving operation determination unit 10e gives priority to the operation by the occupant. Therefore, it is configured to output a request signal according to the operation by the occupant to the control systems 31 to 33. That is, the driving operation determination unit 10e allows the occupant to override the automatic driving support control and perform the driving operation by himself / herself.

The control target calculation unit 10f corrects the target travel route calculated by the target travel route calculation unit 10c, calculates the corrected travel route, and outputs a request signal to the control systems 31 to 33 based on the corrected travel route. It is configured as follows.

For example, when the peripheral target detection unit 10b detects a peripheral target to be avoided, the control target calculation unit 10f corrects the target travel route and calculates the corrected travel route. Further, the control target calculation unit 10f corrects the new target travel route and calculates the corrected travel route even when the target travel route itself is changed due to the change of the driving support mode. The vehicle 1 joins the new target travel route by traveling on this corrected travel route. That is, the corrected travel path in this case is a transitional route for adapting the current vehicle behavior (steering angle, acceleration, etc.) to the vehicle behavior in the new target travel route.

The control target calculation unit 10f uses a predetermined evaluation function to calculate the corrected travel path. The control target calculation unit 10f evaluates a plurality of candidate travel routes using an evaluation function with reference to the target travel route, and one corrected travel optimized to satisfy a predetermined constraint condition (or constraint condition). Calculate the route. Further, in the present embodiment, the evaluation function and the constraint condition are appropriately set based on the selected driving support mode, peripheral target, and the like.

The ECU 10 generates a request signal for at least one or a plurality of the engine control system 31, the brake control system 32, or the steering control system 33 in order to travel on the optimum correction travel path determined by the control target calculation unit 10f. And output.

Next, the driving support mode included in the vehicle control device 100 according to the present embodiment will be described. In the present embodiment, five modes (lane keep control mode, preceding vehicle following mode, automatic speed control mode, speed limit mode, and basic control mode) are provided as driving support modes.

<Lane keep control mode>
The lane keep control mode is a mode in which the vehicle 1 is steered so as to travel near the center of the lane, and is accompanied by automatic steering control and speed control (engine control, brake control) by the vehicle control device 100.

In the present embodiment, when the lane keep control mode is selected (that is, the state in which the LAS switch 36d is operated or pressed), different control is performed depending on whether or not both ends of the lane of the traveling lane can be detected. That is, during the detection of both ends of the lane, the ECU 10 performs steering control and speed control so that the vehicle 1 travels near the center of the traveling lane. However, if both ends of the lane are not detected, the driving support mode is switched to the basic control mode (off mode). In the basic control mode, the driver performs steering operation, accelerator operation, and brake operation.

Both ends of the lane are both ends of the lane in which the vehicle 1 travels (partition lines such as white lines, road edges, curbs, medians, guardrails, etc.), and are boundaries with adjacent lanes, sidewalks, and the like. .. The ECU 10 detects both ends of the lane from the image data captured by the vehicle-mounted camera 21. Further, both ends of the lane may be detected from the map information of the navigation system 30.

<Preceding vehicle following mode>
The preceding vehicle following mode is basically a mode in which the traveling locus of the preceding vehicle is followed by the vehicle 1 while maintaining a predetermined inter-vehicle distance according to the vehicle speed between the vehicle 1 and the preceding vehicle. It is accompanied by automatic steering control and speed control (engine control, brake control) by the device 100.

In the present embodiment, the ECU 10 detects the preceding vehicle based on the image data of the vehicle-mounted camera 21 and the measurement data of the millimeter-wave radar 22. Specifically, another vehicle traveling in front is detected as a traveling vehicle based on the image data obtained by the vehicle-mounted camera 21. Further, in the present embodiment, when the distance between the vehicle 1 and the other vehicle is less than or equal to a predetermined distance (for example, 400 to 500 m) based on the measurement data by the millimeter wave radar 22, the other vehicle is detected as a preceding vehicle. NS. Alternatively, the vehicle-mounted camera 21 and / or the millimeter-wave radar 22 may detect the preceding vehicle and output the preceding vehicle information such as the position of the preceding vehicle to the ECU 10.

In the present embodiment, when the preceding vehicle following mode is selected (that is, the state in which the TJA switch 36b is operated or pressed), different control is performed depending on whether or not the preceding vehicle can be detected. That is, during the detection of the preceding vehicle, the ECU 10 performs steering control and speed control so that the vehicle 1 follows the preceding vehicle. However, while the preceding vehicle is not detected, the driving support mode is switched to the basic control mode (off mode). Alternatively, while the preceding vehicle is not detected, the ECU 10 controls the speed so that the vehicle 1 travels at the set vehicle speed, and the driver performs the steering operation. The set vehicle speed can be set by, for example, the vehicle speed setting switch 37b.

Further, in the alternative preceding vehicle following mode, different controls may be performed depending on whether or not both ends of the lane and the preceding vehicle can be detected. For example, in the alternative preceding vehicle following mode, when both ends of the lane and the preceding vehicle are detected, the ECU 10 does not allow the vehicle 1 to follow the traveling locus of the preceding vehicle, but rather a predetermined inter-vehicle distance from the preceding vehicle. Steering control and speed control are performed so that the vehicle 1 travels near the center of the traveling lane while maintaining the above. On the other hand, when the preceding vehicle is detected but both ends of the lane are not detected, the ECU 10 performs steering control and speed control so that the vehicle 1 follows the traveling locus of the preceding vehicle. Further, when both ends of the lane are detected but the preceding vehicle is not detected, the ECU 10 performs steering control and speed control so that the vehicle 1 travels near the center of the traveling lane at a set vehicle speed. Further, when neither the preceding vehicle nor both ends of the lane is detected, the ECU 10 controls the speed so that the vehicle 1 travels at the set vehicle speed, and the driver performs the steering operation.

<Automatic speed control mode>
Further, the automatic speed control mode is a mode in which the vehicle speed setting switch 37b is used to control the speed so as to maintain a predetermined set vehicle speed (constant speed) preset by the driver, and the vehicle control device 100 automatically controls the speed. Speed control (engine control, brake control) is involved, but steering control is not performed. In this automatic speed control mode, the vehicle 1 travels so as to maintain the set vehicle speed, but the speed may be increased beyond the set vehicle speed by depressing the accelerator pedal by the driver. Further, when the driver operates the brake, the driver's intention is prioritized and the vehicle is decelerated from the set vehicle speed. In addition, when catching up with the preceding vehicle, the speed is controlled so as to follow the preceding vehicle while maintaining the inter-vehicle distance according to the vehicle speed, and when the preceding vehicle disappears, the speed is controlled so as to return to the set vehicle speed again. Will be done.

<Speed limit mode>
Further, the speed limit mode is a mode in which the vehicle speed of the vehicle 1 is controlled so as not to exceed the speed limit by the speed indicator or the set speed set by the driver, and the vehicle control device 100 automatically controls the speed (engine). Control) is involved, but steering control is not performed. The speed limit may be specified by the ECU 10 performing image recognition processing on the speed sign or the image data of the speed display on the road surface captured by the vehicle-mounted camera 21, or may be received by wireless communication from the outside. In the speed limit mode, even if the driver depresses the accelerator pedal so as to exceed the speed limit, the vehicle 1 is only accelerated to the speed limit.

<Basic control mode>
The basic control mode is a mode (off mode) when none of the driving support modes is selected by the driver operation unit 35, and the vehicle control device 100 does not automatically perform steering control and speed control.

Next, the target traveling route calculated by the vehicle control device 100 according to the present embodiment will be described with reference to FIGS. 3 to 5. 3 to 5 are explanatory views of the first traveling route to the third traveling route, respectively. In the present embodiment, the target travel route calculation unit 10c provided in the ECU 10 is configured to repeatedly calculate the following first travel route R1 to third travel route R3 in time (for example, 0.1). Every second). In the present embodiment, the ECU 10 calculates a traveling route from the present time until a predetermined period (for example, 3 seconds) elapses based on the information of the sensor or the like. The travel route Rx (x = 1, 2, 3) is specified by the target position (Px_k) and target speed (Vx_k) of the vehicle 1 on the travel route set every predetermined time (for example, every 0.3 seconds). (K = 0, 1, 2, ..., N). Further, at each target position, target values are specified for a plurality of variables (acceleration, jerk, yaw rate, steering angle, vehicle angle, etc.) in addition to the target speed.

The travel routes (first travel route to third travel route) in FIGS. 3 to 5 are the surroundings related to the target (obstacles such as parked vehicles and pedestrians) on or around the travel path on which the vehicle 1 travels. It is calculated based on the shape of the traveling path, the traveling locus of the preceding vehicle, the traveling behavior of the vehicle 1, and the set vehicle speed without considering the detection information of the target. As described above, in the present embodiment, since the information of the peripheral target is not taken into consideration in the calculation, the overall calculation load of these a plurality of traveling routes can be suppressed to a low level.

Hereinafter, for ease of understanding, each travel route calculated when the vehicle 1 travels on the road 5 including the straight section 5a, the curved section 5b, and the straight section 5c will be described. Road 5 consists of left and right lanes 5 _L and 5 _R. At present, it is assumed that the vehicle 1 is traveling on _{the lane 5 L of the straight section 5a.}

(1st travel route)
As shown in FIG. 3, the first travel path R1 is set for a predetermined period so _{that the vehicle 1 maintains the travel in the lane 5 L} , which is the travel path, in accordance with the shape of the road 5. Specifically, the first travel path R1 is set so that the vehicle 1 maintains the traveling near the center of the _{lane 5 L in} the straight sections 5a and 5c, and the vehicle 1 is set from the center in the width direction of the _{lane 5 L in the curve section 5b.} Is also set to run on the inside or the inside side (the center O side of the radius of curvature L of the curve section).

The target travel route calculation unit 10c executes image recognition processing of image data around the vehicle 1 captured by the vehicle-mounted camera 21 and detects _{both ends 6 L} and 6 _{R of the lane.} Both ends of the lane are lane markings (white lines, etc.), shoulders, etc., as described above. Further, the target traveling route calculation unit 10c calculates the lane width W of the lane 5 _L and the radius of curvature L of the curve section 5b _{based on the detected lane both ends 6 L} and 6 _R. Further, the lane width W and the radius of curvature L may be acquired from the map information of the navigation system 30. Further, the target travel route calculation unit 10c reads the speed sign S and the speed limit displayed on the road surface from the image data. As described above, the speed limit may be acquired by wireless communication from the outside.

In the straight sections 5a and 5c, the target travel route calculation unit 10c is so as to allow the widthwise central portion (for example, the position of the center of gravity) of the vehicle 1 to pass through the widthwise central portions of _{both ends 6 L} and 6 _{R of the lane.} A plurality of target positions P1_k of one travel path R1 are set.

On the other hand, in the curve section 5b, the target travel route calculation unit 10c sets the maximum displacement amount Ws from the center position in the width direction _{of the lane 5 L to the in side at the center position P1_c in the longitudinal direction of the curve section 5b.} This displacement amount Ws is calculated based on the radius of curvature L, the lane width W, and the width dimension D of the vehicle 1 (a specified value stored in the memory of the ECU 10). Then, the target travel route calculation unit 10c sets a plurality of target positions P1_k of the first travel route R1 so as to smoothly connect the central position P1_c of the curve section 5b and the center position in the width direction of the straight sections 5a and 5c. Even before and after entering the curve section 5b, the first travel path R1 may be set on the in side of the straight sections 5a and 5c.

The target speed V1_k at each target position P1_k of the first traveling path R1 is, in principle, a speed set by the driver by the vehicle speed setting switch 37b of the driver operation unit 35, or a predetermined speed set in advance by the vehicle control device 100. It is set to the set vehicle speed (constant speed). However, when this set vehicle speed exceeds the speed limit obtained from the speed indicator S or the like or the speed limit defined according to the radius of curvature L of the curve section 5b, the target speed of each target position P1_k on the traveling route. V1_k is limited to the slower speed limit of the two speed limits. Further, the target traveling route calculation unit 10c appropriately corrects the target position P1_k and the target speed V1_k according to the current behavioral state of the vehicle 1 (that is, vehicle speed, acceleration, yaw rate, steering angle, lateral acceleration, etc.). For example, when the current vehicle speed is significantly different from the set vehicle speed, the target speed is corrected so that the vehicle speed approaches the set vehicle speed.

(Second travel route)
Further, as shown in FIG. 4, the second traveling path R2 is set for a predetermined period so as to follow the traveling locus of the preceding vehicle 3. The target travel route calculation unit 10c is based on the image data by the in-vehicle camera 21, the measurement data by the millimeter wave radar 22, and the vehicle speed of the vehicle 1 by the vehicle speed sensor 23, and the position of the preceding vehicle 3 on the _{lane 5 L on which the vehicle 1 travels.} And the speed are continuously calculated, and these are stored as the preceding vehicle locus information, and based on this preceding vehicle locus information, the traveling locus of the preceding vehicle 3 is set as the second traveling route R2 (target position P2_k, target speed V2_k). Set as.

(Third travel route)
Further, as shown in FIG. 5, the third traveling path R3 is set for a predetermined period based on the current driving state of the vehicle 1 by the driver. That is, the third travel path R3 is set based on the position and speed estimated from the current travel behavior of the vehicle 1.

The target travel route calculation unit 10c calculates the target position P3_k of the third travel route R3 for a predetermined period based on the steering angle, yaw rate, and lateral acceleration of the vehicle 1. However, when both ends of the lane are detected, the target travel route calculation unit 10c corrects the target position P3_k so that the calculated third travel route R3 does not approach or intersect the lane end.

Further, the target travel route calculation unit 10c calculates the target speed V3_k of the third travel route R3 for a predetermined period based on the current vehicle speed and acceleration of the vehicle 1. If the target speed V3_k exceeds the speed limit obtained from the speed sign S or the like, the target speed V3_k may be corrected so as not to exceed the speed limit.

Next, the relationship between the driving support mode and the traveling route in the vehicle control device 100 according to the present embodiment will be described. In the present embodiment, when the driver operates the driver operation unit 35 to select one driving support mode, one of the first to third driving routes is the target driving route according to the selected driving support mode. It is configured to be selected as.

When the lane keep control mode is selected, if both ends of the lane are detected, the first travel route is selected. In this case, the set vehicle speed set by the vehicle speed setting switch 37b becomes the target speed.
Further, when the preceding vehicle following mode is selected, the second traveling route is selected when the preceding vehicle is detected. In this case, the target speed is set according to the vehicle speed of the preceding vehicle. If the preceding vehicle is not detected when the preceding vehicle following mode is selected, the third traveling route is selected.

Further, when the automatic speed control mode is selected, the third traveling route is selected. The automatic speed control mode is a mode in which speed control is automatically executed as described above, and the set vehicle speed set by the set vehicle speed input unit 37 is the target speed. In addition, steering control is executed based on the operation of the steering wheel by the driver.

The third travel route is also selected when the speed limit mode is selected. The speed limit mode is also a mode in which speed control is automatically executed as described above, and the target speed is set in a range equal to or less than the speed limit according to the amount of depression of the accelerator pedal by the driver. In addition, steering control is executed based on the operation of the steering wheel by the driver.

Further, when the basic control mode (off mode) is selected, the third traveling route is selected. The basic control mode is basically the same as the state in which the speed limit is not set in the speed limit mode.

Next, the control target calculation process executed by the control target calculation unit 10f of the ECU 10 according to the present embodiment will be described with reference to FIGS. 6 to 8. FIG. 6 is an explanatory diagram of the control target calculation process, FIG. 7 is an explanatory diagram of the corrected traveling path, and FIG. 8 is an explanatory diagram of the vehicle model. In the present embodiment, the control target calculation process includes a travel route correction process.

As shown in FIGS. 6 and 7, the control target calculation unit 10f corrects the target travel path R according to the change in the external environment (obstacle 3 or the like) or the driving support mode, and calculates the corrected travel path Rc. .. Then, the control target calculation unit 10f calculates a control target value (acceleration target, steering angle target) of a predetermined control amount for the vehicle 1 to travel on the corrected travel path Rc, and the control target calculation unit 10f calculates the control target value (acceleration target, steering angle target) of the vehicle 1 based on the control target. Output the request signal to the control system. Note that FIG. 7 shows an exemplary target travel route R and corrected travel route Rc over a predetermined period (for example, 3 seconds). A target position P and a correction target position Pc are indicated for each of the paths R and Rc at predetermined time intervals (for example, every 0.3 seconds).

Specifically, the control target calculation unit 10f receives various information from the sensor / switch group, receives the target travel route R from the target travel route calculation unit 10c, and receives information on the peripheral target from the peripheral target detection unit 10b. .. Based on this information, the control target calculation unit 10f performs corrected travel optimized so that the amount of deviation from the target travel route R is small while satisfying constraint conditions (avoidance of collision with peripheral targets, etc.). Calculate the path Rc. That is, in the present embodiment, the control target calculation unit 10f provides a solver configured to solve the optimization problem of minimizing the evaluation value of the predetermined evaluation function J under constraints (or under constraints). include. Therefore, the control target calculation unit 10f includes an optimization calculation unit 11a and a model prediction unit 11b.

In the present embodiment, generally, the optimization calculation unit 11a avoids constraints (obstacles, etc.) based on the current behavior (speed, position, acceleration, steering angle, etc.) of the vehicle 1. A candidate correction travel path is set, and physical quantities (acceleration, rudder angle) at each candidate target position on the candidate correction travel path are given to the model prediction unit 11b as input values. The model prediction unit 11b calculates the behavior of the vehicle 1 on the candidate correction travel path by applying the input value to the vehicle model, and feeds back various physical quantities based on the vehicle behavior to the optimization calculation unit 11a.

The vehicle model defines the physical motion of the vehicle 1 and is described by the following equation of motion. This vehicle model is the two-wheel model shown in FIG. 8 in this example. The vehicle model defines the physical movement of vehicle 1.

In FIGS. 8 and (1) and (2), m is the mass of the vehicle 1, I is the yawing inertia moment of the vehicle 1, l is the wheelbase, l _f is the distance between the vehicle center of gravity and the front axle, and l _r is. the distance between the vehicle center of gravity and a rear axle, K _f is tire cornering power per wheel one wheel, K _r is a tire cornering power per rear one wheel, V is the vehicle 1 speed, [delta] is the actual steering angle of the front wheels, β is the lateral slip angle of the vehicle center of gravity, r is the yaw angle velocity of the vehicle 1, θ is the yaw angle of the vehicle 1, y is the lateral displacement of the vehicle 1 with respect to the absolute space, and t is the time.

The optimization calculation unit 11a evaluates the candidate-corrected travel route by using the evaluation function J based on the feedback representing the behavior of the vehicle 1 on the candidate-corrected travel route. In the present embodiment, the evaluation function J includes an evaluation term JE relating to the evaluation of the corrected traveling route and a constraint term JC relating to the constraint condition. The evaluation term JE has a plurality of evaluation factors. Further, the constraint term JC has a plurality of constraint factors. The control target calculation unit 10f sets the evaluation function J so as to be different depending on the driving support mode being executed, the sensor information, and the like.

The plurality of evaluation factors are a plurality of physical quantities representing the behavior of the vehicle 1 at the target position P (for example, velocity (vertical direction and horizontal direction), acceleration (vertical direction and horizontal direction), jerk (vertical direction and horizontal direction), It is set according to the yaw rate, the lateral position with respect to the center of the lane, the vehicle angle, the steering angle, the steering angular velocity, and other soft restrictions). The evaluation factors include a first evaluation factor in which the evaluation is higher as the difference between the physical quantities of the target travel route and the corrected travel route is smaller, and a second evaluation factor in which the evaluation is higher as the size of the physical quantity itself is smaller. In the present embodiment, the smaller the evaluation value, the higher the evaluation.

The first evaluation factor is an evaluation factor for minimizing the difference between the target travel route and the corrected travel route, and the physical quantity of the first evaluation factor is, for example, speed (vertical direction and horizontal direction), horizontal position, and the like. .. On the other hand, the second evaluation factor is an evaluation factor for minimizing a predetermined physical quantity, and the physical quantity of the second evaluation factor is, for example, acceleration (vertical direction and horizontal direction), jerk (vertical direction and horizontal direction), and so on. Steering angle, steering angular velocity, etc.

Further, a plurality of constraint factors are set corresponding to each of a plurality of physical quantities. The constraint factor is estimated as a penalty value according to the amount of the physical quantity exceeding the limit range (lower limit value to upper limit value) specified for the corresponding physical quantity. Therefore, the larger the excess amount, the larger the penalty value (that is, as a result, the larger the evaluation value).

For example, it is fixed in principle for multiple physical quantities including velocity (vertical and horizontal), acceleration (vertical and horizontal), jerk (vertical and horizontal), steering angle, steering angular velocity, and yaw rate. The limit range is specified. However, the limit range may be changed to a range narrower than the fixed limit range. For example, when the speed distribution region (see FIG. 9) described below is applied, the speed limit range with respect to the target 3 is changed according to the position of the vehicle 1.

The evaluation function J (= JE + JC) is described by the following equation.

Regarding the evaluation term JE, in the formula, Wk (Xk-Xrefk) ² is the evaluation factor, Xk is the physical quantity of the candidate correction travel route, Xrefk is the physical quantity of the target travel route or 0 (zero value), and Wk is the weighting coefficient of the evaluation factor ( For example, 0 ≦ Wk ≦ 1) (however, k = 1 to n). Therefore, in the evaluation term JE of the present embodiment, for the physical quantities of n evaluation factors, the physical quantity of the target travel route is changed from the physical quantity of the candidate correction travel route (in the case of the evaluation factor that minimizes the difference from the target travel route) or zero. The sum of the squares of the differences obtained by subtracting the values (in the case of the evaluation factor that minimizes the physical quantity itself) is weighted and corresponds to the total value over the travel path length for a predetermined period (for example, N = 3 seconds). The weighting coefficient Wk is set differently according to each driving support mode.

On the other hand, the constraint term JC corresponds to a value obtained by summing the total value of the evaluation values according to the excess amount from the limit range of the plurality of physical quantities over the travel path length of a predetermined period (for example, N = 3 seconds). Each evaluation value can be, for example, a value obtained by multiplying the squared excess amount by a predetermined weighting coefficient W. The limited range of the predetermined physical quantity may vary depending on the surrounding objects and the like.

In this embodiment, the evaluation function J is a Lagrange function incorporating the constraint term JC. Therefore, the optimization calculation unit 11a is configured to solve an unconstrained optimization problem, and the optimum solution can be derived with good convergence. If the evaluation function J does not include the constraint term JC, and the feedback from the model prediction unit 11b does not satisfy the constraint condition, the feedback does not contribute to the convergence of the optimization problem. In this case, the optimum solution may not be obtained within the predetermined calculation time.

Further, in the present embodiment, even if the feedback does not completely satisfy the constraint condition, the optimization calculation unit 11a evaluates the candidate correction travel route by the evaluation function J in consideration of the constraint condition. Can be done. Thereby, in the present embodiment, the convergence can be improved. For example, it is possible to reliably evaluate a candidate-corrected traveling route that slightly exceeds the constraint condition due to a noise error such as sensor information, an error in evaluating the road environment, an error caused by a model function, or the like. However, in the present embodiment, by setting the weighting coefficient of the constraint term JC to a large value, the constraint term JC can be reliably functioned as a constraint condition.

In the present embodiment, the optimization calculation unit 11a calculates the evaluation value for the candidate correction travel route using the evaluation function J based on the feedback from the model prediction unit 11b. The optimization calculation unit 11a sets a new candidate target travel route according to the evaluation value, and gives a corrected input value to the model prediction unit 11b based on the new candidate correction travel route. In the present embodiment, the evaluation value of the evaluation function J is minimized (or optimized) by repeating such feedback between the optimization calculation unit 11a and the model prediction unit 11b a plurality of times. The travel route Rc is calculated. The maximum number of times the feedback is repeated may be limited to a predetermined number of times.

Next, the obstacle avoidance process according to the present embodiment will be described with reference to FIGS. 9 to 10. FIG. 9 is an explanatory diagram of obstacle avoidance by correcting the target traveling route, and FIG. 10 is an explanatory diagram showing the relationship between the allowable upper limit value of the passing speed between the obstacle and the vehicle and the clearance when avoiding the obstacle. be. In FIG. 9, the vehicle 1 is traveling on the traveling path (lane) 7, and is trying to overtake the vehicle 3 by passing the vehicle 3 which is running or stopped.

Generally, when passing (or overtaking) an obstacle on or near an obstacle (for example, a preceding vehicle, a parked vehicle, a pedestrian, etc.), the driver of the vehicle 1 is in a lateral direction orthogonal to the traveling direction. A predetermined clearance or distance (lateral distance) is maintained between the vehicle 1 and the obstacle, and the speed is reduced to a speed that the driver of the vehicle 1 feels safe. Specifically, in order to avoid the danger of the preceding vehicle suddenly changing course, pedestrians coming out of the blind spot of the obstacle, or the door of the parked vehicle opening, the smaller the clearance, the more the obstacle is dealt with. The relative velocity is reduced.

Further, in general, when approaching the preceding vehicle from behind, the driver of the vehicle 1 adjusts the speed (relative speed) according to the inter-vehicle distance (longitudinal distance) along the traveling direction. Specifically, when the inter-vehicle distance is large, the approach speed (relative speed) is maintained high, but when the inter-vehicle distance is small, the approach speed is reduced. Then, the relative speed between the two vehicles becomes zero at a predetermined inter-vehicle distance. This is the same even if the preceding vehicle is a parked vehicle.

In this way, the driver drives the vehicle 1 without danger while considering the relationship between the distance between the obstacle and the vehicle 1 (including the lateral distance and the vertical distance) and the relative speed. ing.

Therefore, in the present embodiment, as shown in FIG. 9, the vehicle 1 relatives to the obstacle detected from the vehicle 1 (for example, the parked vehicle 3) around the obstacle (lateral region, rear region, And at least between the obstacle and the vehicle 1) or at least a two-dimensional distribution (velocity distribution region 40) that defines an allowable upper limit value for the relative speed in the traveling direction of the vehicle 1 is configured. There is. In the velocity distribution region 40, the permissible upper limit value V _lim of the relative velocity is set at each point around the obstacle.

As can be seen from FIG. 9, in the velocity distribution region 40, in principle, the smaller the lateral distance and the vertical distance from the obstacle (the closer to the obstacle), the smaller the allowable upper limit value of the relative velocity. Set. Further, in FIG. 9, for ease of understanding, an isobaric velocity line connecting points having the same allowable upper limit value is shown. The equal relative velocity lines a, b, c, and d correspond to the permissible upper limit values V _lim of 0 km / h, 20 km / h, 40 km / h, and 60 km / h, respectively. In this example, each equal relative velocity region is set to a substantially rectangular shape.

In the present embodiment, in all the driving support modes, the target traveling route is corrected so that _{the relative speed of the vehicle 1 with respect to the obstacle does not exceed the allowable upper limit value V lim in the speed distribution region 40.} That is, the speed distribution region 40 is a constraint condition for the speed of the vehicle 1. Specifically, the control target calculation unit 10f sets the velocity distribution region 40 for the obstacle when the obstacle (peripheral target) to be avoided is detected by the peripheral target detection unit 10b. Then, the control target calculation unit 10f corrects the target travel route R calculated by the target travel route calculation unit 10c so as not to exceed the _{allowable upper limit value V lim defined by the speed distribution region 40.} The travel route Rc is calculated. FIG. 9 shows exemplary corrected travel paths Rc1, Rc2, Rc3.

The speed distribution region 40 does not necessarily have to be set over the entire circumference of the obstacle, and is at least behind the obstacle and on one side of the obstacle in the lateral direction in which the vehicle 1 exists (vehicle 3 in FIG. 9). It may be set in the area on the right side of.

As shown in FIG. 10, when the vehicle 1 travels at a certain absolute speed, the allowable upper limit value V _lim set in the lateral direction of the obstacle is 0 (zero) until the clearance X is D _{0 (safe distance).} It is km / h and increases in a quadratic function above _{D 0 (V lim} = k (X−D ₀ ) ^2. However, X ≧ D ₀ ). That is, in order to ensure safety, the relative speed of the vehicle 1 becomes zero _{when the clearance X is D 0 or less.} On the other hand, when the clearance X is D ₀ or more, the larger the clearance, the larger the relative speed of the vehicle 1 is allowed to pass.

In the example of FIG. 10, the allowable upper limit value in the lateral direction of the obstacle is _defined by V lim = f (X) = k (X-D ₀ ) ² . Note that k is _{a gain coefficient related to the degree of change in V lim} with respect to X, and is set depending on the type of obstacle and the like. Also, D ₀ is set depending on the type of obstacle and the like.

In the present embodiment, V _lim is defined to be a quadratic function of X, but the present invention is not limited to this, and other functions (for example, a linear function) may be defined. _{Further, although the allowable upper limit value V lim in} the horizontal direction of the obstacle has been described with reference to FIG. 7, it can be set in the same manner in all the radial directions including the vertical direction of the obstacle. At that time, the coefficient k and the safety distance D ₀ can be set according to the direction from the obstacle.

The velocity distribution region 40 can be set based on various parameters. As parameters, for example, the relative speed between the vehicle 1 and the obstacle, the type of the obstacle, the traveling direction of the vehicle 1, the moving direction and the moving speed of the obstacle, the length of the obstacle, the absolute speed of the vehicle 1, etc. should be considered. Can be done. That is, the coefficient k and the safety distance D ₀ can be selected based on these parameters.

Further, in the present embodiment, the obstacles include vehicles, pedestrians, bicycles, cliffs, ditches, holes, falling objects and the like. In addition, vehicles can be distinguished by automobiles, trucks and motorcycles. Pedestrians can be distinguished by adults, children and groups.

As shown in FIG. 9, when the vehicle 1 is traveling on the travel path 7, the peripheral target detection unit 10b built in the ECU 10 of the vehicle 1 is an obstacle (vehicle) based on the image data from the vehicle-mounted camera 21. 3) is detected. At this time, the type of obstacle (in this case, vehicle, pedestrian) is specified.

Further, the peripheral target detection unit 10b calculates the position, relative speed, and absolute speed of the obstacle (vehicle 3) with respect to the vehicle 1 based on the measurement data of the millimeter wave radar 22 and the vehicle speed data of the vehicle speed sensor 23. The position of the obstacle includes an x-direction position (longitudinal distance) along the traveling direction of the vehicle 1 and a y-direction position (horizontal distance) along the lateral direction orthogonal to the traveling direction.

The control target calculation unit 10f sets a velocity distribution region 40 for each of the detected obstacles (vehicle 3 in the case of FIG. 9). Then, the control target calculation unit 10f corrects the target travel path R so that _{the speed of the vehicle 1 does not exceed the allowable upper limit value V lim of the speed distribution region 40.}

That is, when the vehicle 1 travels on the target travel path R, if the target speed exceeds the permissible upper limit value defined by the speed distribution region 40 at a certain target position, the target speed is lowered without changing the target position. Whether to make it (path Rc1 in FIG. 9) or change the target position on the detour route so that the target speed does not exceed the allowable upper limit value without changing the target speed (path Rc3 in FIG. 9), the target position and the target. Both speeds are changed (path Rc2 in FIG. 9).

In general, in the evaluation function J, the corrected traveling path Rc1 is calculated when the weighting coefficient of the evaluation factor for minimizing the steering angular velocity is large, and the weight of the evaluation factor for minimizing the acceleration in the front-rear direction is calculated. When the coefficient is large, the corrected travel path Rc3 is calculated.

For example, FIG. 9 shows a case where the calculated target travel path R is a route traveling at a center position (target position) in the width direction of the travel path 7 at 60 km / h (target speed). In this case, the parked vehicle 3 exists in front as an obstacle, but as described above, this obstacle is not considered in the calculation stage of the target traveling route R in order to reduce the calculation load.

When traveling on the target travel path R, the vehicle 1 crosses the isobaric velocity lines d, c, c, and d of the speed distribution region 40 in order. That is, the vehicle 1 traveling at 60 km / h enters the region inside the equal relative speed line d (allowable upper limit value V _{lim = 60 km / h).} Therefore, the control target calculation unit 10f corrects the target travel path R so as to limit the target speed at each target position of the target travel path R to the allowable upper limit value V _lim or less, and generates the corrected travel path Rc1. That is, in the corrected traveling path Rc1, the target speed gradually decreases to less than 40 km / h as the vehicle approaches the vehicle 3 so that the target speed becomes equal to or less than the _{allowable upper limit value V lim at each target position, and then the vehicle.} The target speed is gradually increased to the original 60 km / h as the distance from 3 is increased.

Further, the corrected travel path Rc3 is set so as to travel outside the isobaric speed line d (corresponding to the relative speed of 60 km / h) without changing the target speed (60 km / h) of the target travel route R. It is a route. In order to maintain the target speed of the target travel path R, the control target calculation unit 10f corrects the target travel path R so as to change the target position so that the target position is located on or outside the equal relative speed line d. Therefore, the corrected travel path Rc3 is generated. Therefore, the target speed of the corrected travel path Rc3 is maintained at 60 km / h, which is the target speed of the target travel path R.

Further, the corrected travel route Rc2 is a route in which both the target position and the target speed of the target travel route R are changed. In the corrected travel path Rc2, the target speed is not maintained at 60 km / h, gradually decreases as it approaches the vehicle 3, and then gradually increases to the original 60 km / h as it moves away from the vehicle 3. Will be done.

A correction that does not change the target position of the target travel path R and changes only the target speed, such as the correction travel path Rc1, can be applied to a driving support mode that involves speed control but not steering control (the correction travel path Rc1). For example, automatic speed control mode, speed limit mode, basic control mode).
Further, a correction for changing only the target position without changing the target speed of the target travel path R, such as the correction travel path Rc3, can be applied to a driving support mode accompanied by steering control (for example, following a preceding vehicle). mode).
Further, a correction for changing both the target position and the target speed of the target traveling path R, such as the corrected traveling path Rc2, can be applied to a driving support mode accompanied by speed control and steering control (for example, a preceding vehicle following mode). ).

Next, with reference to FIG. 11, the processing flow of the driving support control in the vehicle control device 100 of the present embodiment will be described. FIG. 11 is a processing flow of driving support control.
The ECU 10 repeatedly executes the processing flow shown in FIG. 11 at predetermined time intervals (for example, 0.1 seconds). First, the ECU 10 (input processing unit 10a) executes the information acquisition process (S11). In the information acquisition process, the ECU 10 acquires the current vehicle position information and map information from the positioning system 29 and the navigation system 30 (S11a), and the in-vehicle camera 21, millimeter wave radar 22, vehicle speed sensor 23, acceleration sensor 24, and yaw rate sensor. 25, Sensor information is acquired from the driver operation unit 35 and the like (S11b), and switch information is acquired from the steering angle sensor 26, the accelerator sensor 27, the brake sensor 28 and the like (S11c).

Next, the ECU 10 (input processing unit 10a, peripheral target detection unit 10b) executes a predetermined information detection process using various information acquired in the information acquisition process (S11) (S12). In the information detection process, the ECU 10 uses the current vehicle position information, map information, and sensor information to provide lane information (presence / absence of straight section and curved section, length of each section, curve) regarding the shape of the lane in the surrounding and front areas of the vehicle 1. Curvature radius of section, lane width, position at both ends of lane, number of lanes, presence / absence of intersection, speed limit defined by curve curvature, etc.), travel regulation information (speed limit, red light, etc.), preceding vehicle trajectory information (preceding vehicle) (Position and speed), peripheral target information is detected (S12a).

Further, the ECU 10 detects vehicle operation information (steering angle, accelerator pedal depression amount, brake pedal depression amount, etc.) related to vehicle operation by the driver from the switch information (S12b), and further, the vehicle from the switch information and sensor information. The traveling behavior information (vehicle speed, longitudinal acceleration, lateral acceleration, yaw rate, etc.) relating to the behavior of 1 is detected (S12c).

Next, the ECU 10 (target travel route calculation unit 10c) executes the target travel route calculation process based on the information obtained by the calculation (S13). In the target driving route calculation process, as described above, the first traveling route R1, the second traveling route R2, and the third traveling route R3 are calculated, and the driving support mode and the sensor information selected from these are calculated. The target travel route R is selected according to the preceding vehicle, both ends of the lane, etc.).

Next, the ECU 10 (control target calculation unit 10f) executes the control target calculation process based on the target travel path R, peripheral target information, various sensor information, and the like (S14). In the control target calculation process, as described above, the corrected travel path Rc is calculated, and the control target (acceleration target, steering angle target) of a predetermined control amount at each correction target position Pc on the corrected travel path Rc is generated. NS.

Finally, the ECU 10 (control target calculation unit 10f) executes the system control process based on the generated control target in the corrected travel path Rc (S15), and ends the process. In the system control process, request signals (engine request signal, brake request signal, steering request signal) are generated according to the control target in the corrected travel path Rc, and the generated request signals are sent to the control systems 31 to 33 of the vehicle 1. It is output.

Next, the transient evaluation function of the present embodiment will be described with reference to FIGS. 12 to 14. FIG. 12 is an explanatory diagram showing a change in the corrected traveling path when the driving support mode is switched, FIG. 13 is an explanatory diagram showing a change in the weighting coefficient of the evaluation function when the driving support mode is switched, and FIG. 14 is an explanatory diagram showing a change in the weighting coefficient of the evaluation function when the driving support mode is switched. It is explanatory drawing of the switching example of. In the present embodiment, the transient evaluation function Jt is used to calculate the corrected traveling route immediately after switching the driving support mode.

In FIG. 12A, the vehicle 1 and the preceding vehicle 3 are traveling on the travel path 7. Since the preceding vehicle following mode is selected for the vehicle 1, the vehicle 1 is traveling on the target traveling route R along the traveling locus of the preceding vehicle 3. At this time, the preceding vehicle 3 is traveling to the right of the center of the travel path 7.

FIG. 12B shows a state in which the driving support mode is switched to the lane keep control mode in the state of FIG. 12A (the driver operates the LAS switch 36d). At this time, the target travel path R is generated so as to travel at the set speed in the center of the lane of the travel path 7. In the vehicle 1, the corrected travel path Rc is calculated so as to be optimized for the new target travel route R.

At the time of switching the driving support mode (see FIG. 12B), the vehicle 1 is laterally shifted from the target traveling path R. Therefore, when the evaluation function J is used, the corrected travel path Rc quickly increases (or decelerates) the speed of the vehicle 1 to the set speed and quickly moves the vehicle 1 in the lateral direction (left direction). It becomes.

However, at this time, if the behavior of the vehicle 1 changes significantly, the occupant may feel uncomfortable. Therefore, in the present embodiment, the transient evaluation function Jt is used instead of the evaluation function J that is normally used in order to suppress a sudden change in the behavior of the vehicle 1 when the driving support mode is switched.

The transient evaluation function Jt is different from the evaluation function J in that the value of at least one weighting coefficient among the plurality of weighting coefficients of the evaluation function J is set differently. However, except for this point, the transient evaluation function Jt has the same configuration as the evaluation function J. That is, the transient evaluation function Jt includes a transient evaluation term JEt and a transient constraint term JCt. Further, the transient evaluation term JEt and the transient constraint term JCt are composed of a plurality of evaluation factors and a plurality of constraint factors, which are the same as the evaluation term JE and the constraint term JC, respectively.

For example, FIG. 13 shows the time change of the weighting coefficient W of the evaluation factor for minimizing the steering angular velocity (rad / s) included in the second evaluation factor. In FIG. 13, the driving support mode is switched from the preceding vehicle following mode to the lane keep control mode at time t0. The evaluation function J for the preceding vehicle following mode is used up to the time t0, and the evaluation function J for the lane keep control mode is used from the time t1. However, the transient evaluation function Jt is used for the predetermined period T from the time t0 to the time t1.

The weighting coefficient W in the preceding vehicle following mode is a fixed value w2, and the weighting coefficient W in the lane keep control mode is a fixed value w1 (w1 <w2). That is, in the lane keep control mode, in order to maintain the vehicle 1 in the center of the lane, the weighting coefficient W of the evaluation factor of the steering angular velocity is set smaller than the weighting coefficient W in the preceding vehicle following mode. That is, in the lane keep control mode, a steering angular velocity larger than that in the preceding vehicle following mode can be allowed.

The transient weighting coefficient Wt of the evaluation factor of the steering angular velocity in the transient evaluation function Jt in FIG. 13 is set to a value w3 (w3> w2) larger than the fixed value w2 at time t0, decreases at a constant rate of change, and decreases for a predetermined period. After T, the fixed value w1 is reached. That is, immediately after the change of the driving support mode, the value of the transient weighting coefficient Wt becomes large in the transient evaluation function Jt, so that the evaluation of the candidate correction traveling path that sets a large steering angular velocity becomes low (the evaluation value becomes a large value). ), Such a candidate correction travel path is no longer calculated as the correction travel route Rc. Thereby, in the present embodiment, it is possible to suppress a sudden change in behavior at least in the lateral direction immediately after the change of the driving support mode.

Further, in the example of FIG. 13, the weighting coefficient W of the evaluation factor for minimizing the difference in the lateral position from the target traveling route may be temporarily reduced. As a result, the corrected travel path Rc that requires sudden steering in order to reduce the difference in the lateral position is not calculated.

In the present embodiment, the transient weighting coefficient Wt changes linearly in the predetermined period T, but the present invention is not limited to this, and the transient weighting coefficient Wt may change linearly or stepwise.

FIG. 14 shows an example of an evaluation factor that temporarily increases the weighting coefficient and an evaluation factor that temporarily decreases the weighting coefficient according to the combination of the driving support mode before the change and the driving support mode after the change. 12 and 13 are examples of evaluation factors for temporarily increasing the weighting factor of “A” in FIG.

In general, in FIGS. 14A to 14C, in order to suppress sudden steering, the weighting coefficient of the evaluation factor for minimizing the steering angular velocity is temporarily set to be large, and the difference in the lateral position with respect to the target traveling route is set. An example is shown in which the weighting coefficient of the evaluation factor for minimizing the value is temporarily set to be small. Further, in D and E of FIG. 14, in order to suppress sudden acceleration / deceleration, ^{the weighting coefficient of the evaluation factor for minimizing the vertical jerk (m / s 3} ) is temporarily set to be large, and the target speed is set. An example is shown in which the weighting coefficient of the evaluation factor for minimizing the difference in velocity with respect to is temporarily set to be small.

Next, the operation of the vehicle control device 100 according to the embodiment of the present invention will be described.
The vehicle control device 100 provided with a plurality of driving support modes for supporting the driving of the vehicle 1 according to the embodiment of the present invention calculates the target traveling route R of the vehicle 1 (S13) and evaluates the corrected traveling route Rc. The corrected travel path Rc is calculated based on the target travel path R under a predetermined constraint condition using the evaluation function J for the purpose, and the control target value of the vehicle 1 for the vehicle 1 to travel on the corrected travel path Rc is calculated. (S14), the vehicle control device 100 has a plurality of evaluation functions J set differently for each of the plurality of driving support modes, and corresponds to the selected driving support mode. The vehicle control device 100 is configured to use the evaluation function J, further has a transient evaluation function Jt different from the plurality of evaluation functions J for use when changing the driving support mode, and changes the driving support mode. It is characterized in that the transient evaluation function Jt is used instead of the evaluation function J in the later predetermined period T.

In the present embodiment configured in this way, when the driving support mode is changed, the evaluation function J used for calculating the corrected traveling path Rc is not suddenly switched in accordance with the change in the driving support mode. The transient evaluation function Jt is used instead only for a predetermined period T after the change of the driving support mode. Then, after the elapse of the predetermined period T, the evaluation function J for the changed driving support mode is used. Therefore, in the present embodiment, it is possible to suppress the calculation of the corrected travel path Rc that abruptly changes the vehicle behavior immediately after the change of the driving support mode.

Further, in the present embodiment, the transient evaluation function Jt is set differently depending on the combination of the driving support mode before the change and the driving support mode after the change. In the present embodiment configured in this way, an appropriate transient evaluation function Jt that stabilizes the vehicle behavior immediately after the change of the driving support mode can be set according to the combination of the driving support modes before and after the change. ..

Further, in the present embodiment, the vehicle control device 100 uses the evaluation function J or the transient evaluation function Jt to calculate evaluation values for a plurality of candidate-corrected travel routes and correct the candidate-corrected travel route with the best evaluation value. Calculated as the travel route Rc.

Further, in the present embodiment, the evaluation function J includes the sum of a plurality of evaluation factors each weighted by the weighting coefficient W, and the weighting coefficient W is set to be different according to the driving support mode, and is a transient evaluation. The function Jt includes the sum of a plurality of evaluation factors weighted by the transient weighting coefficient Wt, and the transient weighting coefficient Wt is set according to the combination of the driving support mode before and after the change of the driving support mode. ..

In the present embodiment configured in this way, by setting the transient weighting coefficient Wt according to the combination of the driving support modes, an appropriate transient evaluation function Jt that stabilizes the vehicle behavior immediately after the change of the driving support mode is provided. Can be set.

Further, in the present embodiment, the transient weighting coefficient Wt of at least one evaluation factor is set to change from the initial value w3 with the passage of time in the predetermined period T after the change of the driving support mode, and after the predetermined period T elapses. It matches the value w1 of the weighting coefficient W of at least one evaluation factor of the evaluation function J of the changed driving support mode.

In the present embodiment configured as described above, the value of the transient weighting coefficient Wt can be gradually brought closer to the value of the weighting coefficient W of the changed driving support mode in the predetermined period T after the change of the driving support mode. Thereby, in the present embodiment, after the driving support mode is changed, the behavior of the vehicle 1 can be smoothly approached to the vehicle behavior of the changed driving support mode.

Further, in the present embodiment, the transient weighting coefficient Wt is set so that the weighting of the evaluation factor regarding the lateral position of the vehicle 1 is smaller than the weighting coefficient W of the changed driving support mode (FIG. 14). A to C) and / or the weighting of the evaluation factor regarding the steering angular velocity of the vehicle 1 is set to be large (A to C in FIG. 14).

In the present embodiment configured in this way, even if the target travel route shifts laterally from the current position of the vehicle 1 due to the change in the driving support mode, a corrected travel route that requires sudden steering is required. It is possible to suppress the calculation of Rc. For example, the evaluation factor relating to the lateral position of the vehicle 1 is an evaluation factor for minimizing the difference between the lateral position of the target traveling path and the corrected traveling path, and the evaluation factor relating to the steering angular velocity of the vehicle 1 is corrected. This is an evaluation factor for minimizing the steering angular velocity of the vehicle 1 on the traveling route.

Further, in the present embodiment, the transient weighting coefficient Wt is smaller than the weighting coefficient W of the changed driving support mode for the evaluation factor regarding the speed of the vehicle 1 (D, E in FIG. 14), or the vehicle. It is set to increase the weighting of the evaluation factor related to the jerk in the front-rear direction of 1 (D and E in FIG. 14) or to increase the weighting of the evaluation factor related to the acceleration of the vehicle 1 in the front-rear direction (D and E in FIG. 14). D and E in FIG. 14).

In the present embodiment configured in this way, sudden acceleration / deceleration occurs even when there is a difference between the current vehicle speed of the vehicle 1 and the target speed on the target travel path due to the change in the driving support mode. It is possible to suppress the calculation of the required corrected travel path Rc. For example, the evaluation factor relating to the speed of the vehicle 1 is an evaluation factor for minimizing the difference between the target speed on the target traveling route and the vehicle speed on the corrected traveling route, and the evaluation factor relating to the jerk in the front-rear direction of the vehicle 1 is The evaluation factor for minimizing the jerk in the front-rear direction of the vehicle 1 on the corrected traveling path, and the evaluation factor for the acceleration in the front-rear direction of the vehicle 1 is the evaluation factor for minimizing the acceleration in the front-rear direction of the vehicle 1 on the corrected traveling path. It is an evaluation factor to do.

1 Vehicle 3 Target (obstacle, preceding vehicle)
5 Roads 5L, 5R Lanes 7 Driveways 10 ECU
10a Input processing unit 10b Peripheral target detection unit 10c Target travel route calculation unit 10e Driving operation judgment unit 10f Control target calculation unit 11a Optimization calculation unit 11b Model prediction unit 40 Speed distribution area 100 Vehicle control device J evaluation function Jt Transient evaluation function P Target position Pc Corrected target position R Target travel route R1-R3 1st to 3rd travel route Rc Corrected travel route W Weight coefficient Wt Transient weight coefficient

Claims (5)

A vehicle control device having a plurality of driving support modes for supporting the driving of a vehicle, wherein the vehicle control device is
Calculate the target travel route of the vehicle and
Using an evaluation function for evaluating the corrected travel route, the corrected travel route is calculated based on the target travel route under predetermined constraint conditions, and the vehicle travels on the corrected travel route. It is configured to calculate the control target value,
The vehicle control device has a plurality of evaluation functions set differently for each of the plurality of driving support modes, and is configured to use the evaluation function corresponding to the selected driving support mode. ,
The vehicle control device further has a transient evaluation function different from the plurality of evaluation functions to be used when the driving support mode is changed, and replaces the evaluation function in a predetermined period after the change of the driving support mode. A vehicle control device that uses the transient evaluation function. The evaluation function includes the sum of a plurality of evaluation factors each weighted by a weighting coefficient, and the weighting coefficient is set to be different according to the driving support mode.
The transient evaluation function includes the sum of the plurality of evaluation factors, each weighted by a transient weighting factor.
The vehicle control device according to claim 1, wherein the transient weighting coefficient is set according to a combination of the driving support modes before and after the change of the driving support mode. The transient weighting coefficient of at least one evaluation factor is set to change from the initial value with the lapse of time in a predetermined period after the change of the driving support mode, and the changed driving support mode after the lapse of the predetermined period. The vehicle control device according to claim 2, which matches the value of the weighting coefficient of the at least one evaluation factor of the evaluation function. The transient weighting factor is set so that the weighting of the evaluation factor regarding the lateral position of the vehicle is smaller than the weighting factor of the changed driving support mode, and / or the evaluation of the steering angular velocity of the vehicle. The vehicle control device according to claim 2 or 3, which is set to increase the weighting of factors. Whether the transient weighting coefficient has a smaller weighting for the evaluation factor regarding the speed of the vehicle or a larger weighting regarding the evaluation factor regarding the jerk in the front-rear direction of the vehicle than the weighting coefficient of the changed driving support mode. Or, the vehicle control device according to claim 2 or 3, which is set to increase the weighting of the evaluation factor regarding the acceleration of the vehicle in the front-rear direction.

Images