JP2014196022A - Drive assistance controller - Google Patents

Abstract

PROBLEM TO BE SOLVED: To realize speed recovery assistance with respect to a decrease in a vehicle speed without a driver's intention while being adapted to surrounding traffic environment without giving the driver discomfort.SOLUTION: If conditions that a speed of a vehicle decreases and a distance between the vehicle and a preceding vehicle tends to increase after the vehicle passes through an upward slope start point are satisfied, a control is executed for adjusting an output torque to be increased in a relation between an accelerator opening and the output torque as a speed recovery assistance control. Since the speed recovery assistance control is executed in view of the presence of the preceding vehicle, it is possible to adapt the speed recovery assistance control to surrounding traffic environment. Since the speed recovery assistance control is executed while adjusting the relation between the acceleration opening and the output torque, it is possible to prevent a driver from being given discomfort. Furthermore, if the vehicle speed tends to decrease and the distance between the vehicle and the preceding vehicle tends to decrease (if the decrease in the vehicle speed derives from deceleration of the preceding vehicle), the speed recovery assistance control is not executed. Therefore, the driver is not given discomfort in a case where the driver does not want the acceleration of the vehicle.

Description

  The present invention relates to a driving support control apparatus that executes speed recovery support control for recovering a vehicle speed that has decreased against the driver's intention, particularly on an uphill as vehicle driving support control.

JP 2008-257635 A JP 2008-222123 A

  For example, as described in Patent Documents 1 and 2 described above, there is known a vehicle driving support control that performs control for speed recovery support in response to a decrease in speed on an uphill. On the uphill, the vehicle speed may decrease against the driver's intention, and in such a case, assistance is provided so that the vehicle speed recovers.

  Specifically, in the invention described in Patent Document 1, when a speed decrease is detected after passing through the sag portion (corresponding to reaching an uphill), the accelerator opening is automatically adjusted to adjust the sag portion. It returns to the vehicle speed when passing.

  Further, in the invention described in Patent Document 2, when the gradient change point is reached, an average when the distance between the vehicle and the preceding vehicle (preceding vehicle) is more than a predetermined distance and the current vehicle speed is traveling on a flat surface is obtained. When the vehicle speed is lower than the vehicle speed, the vehicle speed is recovered by auto-cruise control.

  However, in the invention described in Patent Document 1, even if the speed reduction of the host vehicle is caused by the speed reduction of the preceding vehicle, the acceleration control is automatically executed, which gives the driver a sense of incongruity. There is a fear. Moreover, since the preceding vehicle is not considered in the control, it cannot be adapted to the surrounding traffic environment.

In addition, although the invention described in Patent Document 2 considers the presence of a preceding vehicle, since the auto cruise control is executed as a control for actually recovering the speed, there is a risk of giving the driver a sense of incongruity. .
For example, even when the inter-vehicle distance from the preceding vehicle is more than a predetermined distance, when the preceding vehicle decelerates, there may be a case where the own vehicle also wants to decelerate (or does not want to increase the vehicle speed although it does not want to decelerate). obtain. In the invention described in Patent Document 2, auto-cruise control, that is, speed recovery control that does not involve the driver's intention, is executed even in the case where the driver does not want to accelerate. There is a risk of discomfort.

  Therefore, the present invention overcomes the above-mentioned problems and realizes speed recovery support control for a decrease in the host vehicle speed that is not intended by the driver so that the driver does not feel uncomfortable while adapting to the surrounding traffic environment. With the goal.

  1stly, the driving assistance control apparatus of this invention is the own vehicle speed detection part which detects the own vehicle speed as a running speed of the own vehicle, The gradient change point detection part which detects the gradient change point as a starting point of an uphill, A preceding vehicle detecting unit that detects the preceding vehicle, an output torque adjusting unit that adjusts the relationship between the accelerator opening and the output torque, and the own vehicle speed decreases and the preceding vehicle decreases after the own vehicle passes the gradient change point. A control unit that executes control for adjusting the output torque to the increase side by the output torque adjustment unit as speed recovery support control when the condition that the inter-vehicle distance tends to increase is satisfied. It is to be prepared.

According to the above configuration, since the speed recovery support control is executed in consideration of the presence of the preceding vehicle, the control is performed in consideration of the surrounding traffic environment.
In addition, the control for actually recovering the speed is not the automatic adjustment of the accelerator opening or the automatic cruise control as in the conventional case, but the control for adjusting the relationship between the accelerator opening and the output torque. The driver's will will intervene, and the driver will not feel uncomfortable.
Further, since the speed recovery support control is performed when the inter-vehicle distance with the preceding vehicle is increasing, when the own vehicle speed is decreasing and the inter-vehicle distance with the preceding vehicle is decreasing, that is, the own vehicle speed When the decrease is caused by the deceleration of the preceding vehicle, the speed recovery support control is not executed. Therefore, the speed recovery support control is not executed in the case where the driver does not desire acceleration, and the driver does not feel uncomfortable in this respect.

Secondly, in the driving support control apparatus according to the present invention described above, the output torque adjustment unit can change and set the engine output characteristics stepwise according to an operation, and the control unit As speed recovery support control, it is desirable to perform control to change the engine output characteristic to a torque-oriented engine output characteristic.
According to the above configuration, since the existing engine output characteristic adjustment function can be used for speed recovery support control, there is a need to have special control information for speed recovery support control as control information for realizing engine output characteristics. Absent. When the driver wants to change the engine output characteristic set by the speed recovery support control, the desired engine output characteristic can be set by operation.

Thirdly, in the driving support control apparatus according to the present invention described above, the control unit continues the host vehicle speed for a predetermined time or during a predetermined distance after the host vehicle passes the gradient change point. It is desirable to execute the speed recovery support control when the condition that the distance between the vehicle and the preceding vehicle is continuously increasing and the distance between the preceding vehicles is continuously increasing is satisfied.
As a result, the driving support control is not executed when the host vehicle speed is temporarily decreased or the inter-vehicle distance from the preceding vehicle is temporarily increased.

4thly, in the drive assistance control apparatus which concerns on above-described this invention, the sag part detection part which detects the sag part which exists ahead of the own vehicle is provided, and the own vehicle comprises the sag part. It is desirable to execute the speed recovery support control when the condition is satisfied after passing through the gradient change point.
As a result, speed recovery support for the driving state after passing the gradient changing point (gradient changing point as the uphill starting point) that constitutes the sag, that is, the driving state in the case where the probability of occurrence of congestion is high Control is executed.

Fifth, in the driving support control apparatus according to the present invention described above, the gradient change point detection unit can detect a gradient change point as an end point of an uphill, and the control unit is configured so that the host vehicle In response to reaching the slope change point as the end point of the uphill, the brake operation being performed, or the accelerator pedal being suddenly released, the operation for canceling the operation performed by the speed recovery support control is performed. It is desirable.
As a result, when there is no risk of a decrease in the vehicle speed due to the uphill, or when the driver wants to consciously decrease the vehicle speed, the operation for speed recovery support is automatically canceled. The

  ADVANTAGE OF THE INVENTION According to this invention, the speed recovery assistance with respect to the speed fall which a driver does not intend can be implement | achieved so that a driver may not feel uncomfortable, adapting to the surrounding traffic environment.

It is the figure which showed the structure of the vehicle control system of embodiment. It is a figure for demonstrating the image processing performed in embodiment. It is explanatory drawing of a sag part. It is a flowchart which shows the specific procedure of the main process which concerns on speed recovery assistance. It is the flowchart which showed the procedure of the specific process which should be performed as a speed recovery assistance relevant process. Similarly, it is a flowchart showing a procedure of specific processing to be executed as speed recovery support related processing.

<1. Overall system configuration>
FIG. 1 shows a configuration of a vehicle control system 1 including a driving support control device as an embodiment according to the present invention. In FIG. 1, only the configuration of the main part according to the present invention is extracted and shown from the configuration of the vehicle control system 1.
The vehicle control system 1 includes an imaging unit 2, an image processing unit 3, a memory 4, a driving support control unit 5, a display control unit 6, an engine control unit 7, a transmission control unit 8, and a brake control unit provided for the host vehicle. 9, sensor / operator 10, display unit 11, engine-related actuator 12, transmission-related actuator 13, brake-related actuator 14, and bus 15.

  The image processing unit 3 performs predetermined image processing for recognizing an environment outside the vehicle based on captured image data obtained by the imaging unit 2 imaging the front of the host vehicle. The image processing by the image processing unit 3 is performed using, for example, a memory 4 that is a non-volatile memory. Details of the internal configuration of the imaging unit 2 and specific processing executed by the image processing unit 3 will be described later.

The driving support control unit 5 is configured by a microcomputer including, for example, a CPU (Central Processing Unit), a ROM (Read Only Memory), a RAM (Random Access Memory), and the like. Various control processes for driving support are executed based on detection information, operation input information, and the like obtained by the operators 10.
The driving support control unit 5 is connected to each control unit of the display control unit 6, the engine control unit 7, the transmission control unit 8, and the brake control unit 9 which are also configured by a microcomputer via a bus 15. Data communication can be performed with the control unit. The driving support control unit 5 instructs a necessary control unit among the above control units to execute an operation related to driving support.
In the case of the present embodiment, the driving support control unit 5 executes a control process for speed recovery support for a decrease in the host vehicle speed on an uphill. In the drawing, the speed recovery support processing function of the driving support control unit 5 is represented by a functional block as a “speed recovery support processing unit 5A”. As will be described later, the speed recovery support processing unit 5A realizes the speed recovery support operation as an embodiment by executing the processes shown in FIGS.

The sensors / operators 10 comprehensively represent various sensors and operators provided in the host vehicle. Sensors / operators 10 include, for example, an engine speed sensor, an intake air amount sensor that detects the intake air amount, an accelerator opening sensor that detects the accelerator opening amount from the depression amount of the accelerator pedal, and an intake passage. A throttle opening sensor that detects the opening of a throttle valve that adjusts the amount of intake air supplied to each cylinder of the engine, a water temperature sensor that detects the cooling water temperature that indicates the engine temperature, and an outside air temperature sensor that detects the temperature outside the vehicle Etc.
In addition, as an operator, an ignition switch for instructing start / stop of the engine, selection of an automatic transmission mode / manual transmission mode in an AT (automatic transmission) vehicle, and an instruction for up / down in the manual transmission mode are given. There are a select lever for performing, a display changeover switch for switching display information in an MFD (Multi Function Display) provided in the display unit 11 described later, and the like.
Particularly in the case of the present embodiment, the sensor / operator 10 includes a vehicle speed sensor 10A, a brake switch 10B, an accelerator opening sensor 10C, and a mode selection switch 10D. Note that the brake switch 10B is a switch that is turned ON / OFF according to the operation of the brake pedal.

  Here, the mode selection switch 10D is a switch for selecting an arbitrary traveling mode from a plurality of traveling modes. In this example, three types of travel modes, “normal mode”, “save mode”, and “power mode”, are prepared, and the mode selection switch 10D has, for example, a ring-shaped operation element. One driving mode can be selected from the modes.

At least the engine output characteristics are switched depending on the switching of the running mode. The “normal mode” is a mode set so that the output torque changes substantially linearly with respect to the accelerator opening. The “save mode” is set as a mode in which the output torque is saved as compared with the “normal mode”, and is a mode that achieves both easy drive performance and low fuel consumption. “Power mode” is a mode that is set to provide excellent output characteristics from low to high engine speeds compared to “normal mode”. Generate maximum torque.
As described above, the “normal mode” is a mode in which torque is more important than “save mode”, and the “power mode” is a mode in which torque is more important than “normal mode”. By changing to a mode that emphasizes more torque, the output torque for the same accelerator opening tends to increase.
In the case of this example, the shift schedule (relationship between the engine speed and the shift timing) is switched together with the engine output characteristics in accordance with the switching of the running mode. It is also described in “Publication”.

  The display unit 11 comprehensively represents various meters such as a speedometer and a tachometer provided in a meter panel installed in front of the driver, an MFD, and other display devices for presenting information to the driver. Various information such as the total travel distance of the host vehicle, the outside air temperature, and instantaneous fuel consumption can be displayed on the MFD simultaneously or by switching.

  The display control unit 6 controls the display operation by the display unit 11 based on a detection signal from a predetermined sensor in the sensor / operator 10, operation input information by the operator, and the like. In particular, the display control unit 6 in the present embodiment displays information representing the different travel modes selected by the above-described mode selection switch 10D in a predetermined area in the above-described MFD. The display control unit 6 of the present embodiment displays a predetermined alert message on the display unit 11 (for example, a predetermined area of the MFD) as part of the speed recovery support based on an instruction from the driving support control unit 5. This will be described later.

The engine control unit 7 controls various actuators provided as the engine-related actuator 12 based on a detection signal from a predetermined sensor in the sensor / operator 10 or operation input information by the operator. As the engine-related actuator 12, for example, various actuators related to engine driving such as a throttle actuator that drives a throttle valve and an injector that performs fuel injection are provided.
For example, the engine control unit 7 performs engine start / stop control according to the operation of the ignition switch described above. The engine control unit 7 also controls the fuel injection timing, the fuel injection pulse width, the throttle opening, and the like based on detection signals from predetermined sensors such as an engine speed sensor and an accelerator opening sensor.

  Here, the engine control unit 7 is provided with a mode map corresponding to each travel mode described above, and based on these mode maps, the target is determined based on two parameters of the engine speed and the accelerator opening for each travel mode. Set the torque. Then, a throttle opening signal corresponding to the set target torque is output to the throttle actuator to open and close the throttle valve.

  In the case of the present embodiment, the instruction of the travel mode to be set is not only the operation of the mode selection switch 10D described above, but also from the driving support control unit 5 in accordance with the speed recovery support control as an embodiment described later. Sometimes done. When the engine control unit 7 is setting the travel mode according to the instruction from the driving support control unit 5 in accordance with the speed recovery support control, when switching to another travel mode is instructed by the operation of the mode selection switch 10D. The instruction according to the operation of the mode selection switch 10D is given priority.

The transmission control unit 8 controls various actuators provided as the transmission-related actuator 13 based on a detection signal from a predetermined sensor in the sensor / operator 10 or operation input information by the operator. As the transmission-related actuator 13, there are provided various transmission-related actuators such as a control valve that performs shift control of an automatic transmission and a lockup actuator that locks up a lockup clutch.
For example, when the automatic shift mode is selected by the select lever described above, the transmission control unit 8 performs a shift control by outputting a shift signal to the control valve according to a predetermined shift pattern. In the case of this example, this shift pattern is variably set according to the travel mode set by the engine control unit 7.
In addition, when the manual shift mode is set, the transmission control unit 8 performs a shift control by outputting a shift signal according to a shift up / down instruction from the select lever to the control valve.

The brake control unit 9 controls various actuators provided as the brake-related actuators 14 based on detection signals from predetermined sensors in the sensors / operators 10 and operation input information by the operators. As the brake-related actuator 14, for example, various brake-related actuators such as a hydraulic pressure control actuator for controlling the hydraulic pressure output from the brake booster to the master cylinder and the hydraulic pressure in the brake fluid piping are provided.
For example, when an instruction to turn on the brake is issued from the driving support control unit 5, the brake control unit 9 controls the hydraulic pressure control actuator to brake the host vehicle. Further, the brake control unit 9 calculates a wheel slip ratio from detection information of a predetermined sensor (for example, an axle rotation speed sensor or a vehicle speed sensor), and increases or decreases the hydraulic pressure by the hydraulic pressure control actuator according to the slip ratio. By so doing, so-called ABS (Antilock Brake System) control is realized.

<2. Image processing executed in this embodiment>
The image processing executed in this embodiment will be described with reference to FIG.
In FIG. 2, in order to describe image processing, the internal configuration of the imaging unit 2 and the memory 4 shown in FIG. 1 are shown together with the configuration of the image processing unit 3. First, the imaging unit 2 for obtaining captured image data used for image processing will be briefly described.
The imaging unit 2 includes a first camera unit 20-1, a second camera unit 20-2, an A / D converter 21-1, an A / D converter 21-2, and an image correction unit 22. .
Each of the first camera unit 20-1 and the second camera unit 20-2 includes a camera optical system and an image sensor such as a charge coupled device (CCD) or a complementary metal oxide semiconductor (CMOS). A subject image is formed on the imaging surface of the imaging device by the optical system, and an electrical signal corresponding to the amount of received light is obtained in pixel units by the imaging device.
The first camera unit 20-1 and the second camera unit 20-2 are installed so as to enable distance measurement by a so-called stereo method. The first camera unit 20-1 and the second camera unit 20-2 in this example are arranged at a predetermined interval in the vehicle width direction in the vicinity of the upper part of the windshield of the host vehicle. The optical axes of the first camera unit 20-1 and the second camera unit 20-2 are parallel, and the focal lengths are the same. Also, the frame periods are synchronized and the frame rates are the same.

The electrical signal obtained by the image sensor of the first camera unit 20-1 is sent to the A / D converter 21-1, and the electrical signal obtained by the image sensor of the second camera unit 20-2 is sent to the A / D converter 21. -2 and A / D conversion is performed respectively. As a result, a digital image signal (image data) representing a luminance value with a predetermined gradation in pixel units is obtained.
The image correction unit 22 includes image data based on an image captured by the first camera unit 20-1 obtained through the A / D converter 21-1 (hereinafter referred to as “first captured image data”), A / D Image data (hereinafter referred to as “second captured image data”) based on the image captured by the second camera unit 20-2 obtained via the D converter 21-2 is input. For example, the image correction unit 22 corrects a deviation caused by an error in the attachment positions of the first camera unit 20-1 and the second camera unit 20-2 for each of the first captured image data and the second captured image data. Use affine transformation or the like. The image correction unit 22 also corrects the luminance value including noise removal for each of the first captured image data and the second captured image data.

  The first captured image data and the second captured image data obtained by the imaging unit 2 are recorded and held in the memory 4 by the image processing unit 3.

The image processing unit 3 is configured by, for example, a microcomputer, and executes various types of image processing based on the first captured image data and the second captured image data according to the activated program.
In FIG. 2, various types of image processing executed by the image processing unit 3 are shown in blocks for each function. As shown in the figure, the image processing unit 3 is roughly classified according to function. The distance image generation processing unit 3A, the lane detection processing unit 3B, the lane model formation processing unit 3C, the preceding vehicle detection processing unit 3D, and the sag detection unit 3E. And a gradient change point arrival detection processing unit 3F.

  The distance image generation process executed by the distance image generation processing unit 3A is a process of generating a distance image based on the first captured image data and the second captured image data held in the memory 4. Specifically, the distance image generation process detects the corresponding points between the first captured image data and the second captured image data (that is, a pair of image data captured in stereo) by pattern matching, and between the detected corresponding points. Is a process of generating distance image data in which the distance to the corresponding point in the real space is represented on the image based on the principle of triangulation using the parallax.

  The lane detection processing executed by the lane detection processing unit 3B is generated by a reference image (that is, image data set in advance among the first captured image data or the second captured image data) and the distance image generation processing described above. Based on the distance image data (distance information for each pixel as a corresponding point), the lane formed on the road surface on which the host vehicle travels is detected. Specifically, in the lane detection process, first, a lane candidate point is detected on the reference image based on the luminance value of each pixel of the reference image and the distance in the real space of each pixel, and the lane detection point is automatically detected based on the detected lane candidate point. The left and right lane positions of the vehicle are detected. For example, a search is performed by offsetting a horizontal line having a width of one pixel on the reference image by one pixel in the left-right direction, and the luminance differential value (= edge strength) of each pixel is a threshold value based on the luminance value of each pixel of the reference image. Pixels that satisfy the conditions that change greatly as described above are detected as lane candidate points. This process is sequentially performed while offsetting the horizontal line to be searched for by one pixel width upward, for example, from the lower side of the reference image. Thereby, a lane candidate point is detected in each of the right region and the left region of the host vehicle.

The lane model formation process executed by the lane model formation processing unit 3C is based on the information on the left and right lane candidate points detected by the above lane detection, and the X, Y, and Z axes (the X axis is the left and right direction, the Y axis Is a process for forming a lane model in a three-dimensional space defined by the height direction and the Z-axis the vehicle traveling direction). Specifically, the lane model in the three-dimensional space is formed by linearly approximating the position (X, Y, Z) of the lane candidate point detected by the lane detection unit in the real space by, for example, the least square method. .
With the lane model formed in this way, the height information of the road surface on which the host vehicle travels can also be obtained.

  Note that the method of the distance image generation process, the lane detection process, and the lane model formation process is the same as the technique disclosed in Japanese Patent Application Laid-Open No. 2008-33750.

The preceding vehicle detection process executed by the preceding vehicle detection processing unit 3D is a process for detecting a preceding vehicle existing ahead of the host vehicle based on the reference image and the distance image. In this preceding vehicle detection process, first, an object detection process is performed based on a distance image, and an object present in the image is detected including information on the distance to the object. For example, as this object detection processing, the distance image is divided into a plurality of vertical regions that divide the distance image in the vertical direction, and a distance histogram that represents a distance distribution in the image vertical direction (Y direction) is created for each vertical region, The distance of the position (corresponding point) where the frequency is maximum is set as the representative distance of the object existing in the vertical region. Then, for each corresponding point with the maximum frequency for which the representative distance is obtained, pixel ranges that are regarded as the same object are grouped from the relationship such as the distance and direction to each corresponding point adjacent to each other, and each existing in the image Specify the range of the object. Thereby, an object existing in the image is detected including information on the distance to the object.
Here, the distance image is sequentially generated for each frame. In the preceding vehicle detection process, information on the distance of the detected object is monitored over a plurality of frames, so that an object that exists on the traveling path of the own vehicle and moves at a predetermined speed in substantially the same direction as the own vehicle is preceded. Extract as a vehicle. At this time, in order to suppress erroneous detection of an object other than the vehicle, pattern matching using a reference image (for example, pattern matching based on a feature point of the vehicle such as a brake lamp) is also performed.
When the preceding vehicle is detected, the preceding vehicle detection information includes the preceding vehicle distance (= inter-vehicle distance), the preceding vehicle speed (= change ratio of the inter-vehicle distance + own vehicle speed), and the preceding vehicle acceleration (= differential of the preceding vehicle speed). Value).
Note that the method of the preceding vehicle detection process is the same as the method disclosed in Japanese Patent Application Laid-Open No. 2012-66759. For details, refer to this document.

The sag detection processing executed by the sag detection processing unit 3E is a process for detecting a sag that exists in front of the host vehicle.
Here, the sag portion means a concave portion that reaches from the downhill to the uphill, and in particular, on a road where a relatively gentle uphill follows a downhill as shown in FIGS. 3A and 3B. This refers to the part where the slope changes from a downward slope to an upward slope. In these drawings, a broken line indicated by “H” means a flat surface (gradient = 0%).
In FIG. 3A, the end point of the downhill coincides with the start point of the uphill, and in this case, the slope change point between the downhill and the uphill indicated by “Pc” in the figure is the sag portion. . In the example of FIG. 3B, a flat portion is interposed between the downhill and the uphill, and in this case, the flat portion is a sag portion. Hereinafter, the gradient change point to the uphill constituting the sag portion is referred to as “gradient change point Pc”.

In the case of this example, in the sag part detection process, a sag part existing in front of the host vehicle is detected based on the information of the lane model obtained by the lane model formation process described above. Specifically, in the sag detection processing in this case, when there is an uphill after a downhill and the gradient difference is 1.5% or more, it is detected that the sag is present in front of the host vehicle. Get results. Note that the slope difference is calculated with the downhill slope being minus and the uphill slope being plus.
In the sag detection process, when a sag is detected in front of the host vehicle, the sag detection flag is set to ON. Here, the sag detection flag is recorded in a predetermined area of the memory 4.

The gradient change point arrival detection processing executed by the gradient change point arrival detection processing unit 3F is performed at the gradient change point to the uphill gradient (that is, the starting point of the uphill) and the gradient change point from the uphill (uphill end point). This is a process for detecting that the host vehicle has arrived.
Specifically, in the gradient change point arrival detection process, the host vehicle reaches the gradient change point to the climb slope and the slope change point from the climb slope based on the result of monitoring the lane model information obtained in the lane model formation process. Detect that
In the gradient change point arrival detection process, when it is detected that the vehicle has reached the gradient change point to the climbing gradient, the gradient change point arrival flag is set to ON. Further, when it is detected that the host vehicle has reached the slope change point from the uphill, the uphill end point arrival flag is set to ON.
These gradient change point arrival flag and climbing end point arrival flag are also recorded in a predetermined area of the memory 4.

<3. Processing for speed recovery support>
With reference to the flowcharts of FIGS. 4 to 6, a specific processing procedure executed by the driving support control unit 5 illustrated in FIG. 1 as the speed recovery support processing unit 5 </ b> A will be described.
FIG. 4 shows a specific procedure of main processing executed by the speed recovery support processing unit 5A.
First, in step S101, the sag portion detection flag recorded in the memory 4 is confirmed, and in the subsequent step S102, it is determined whether or not the sag portion is detected, that is, whether or not the sag portion detection flag is ON. If the sag portion detection flag is not ON and the sag portion is not detected, the process returns to step S101. On the other hand, if it is determined that the sag portion detection flag is ON and the sag portion is detected, the process proceeds to step S103.

  In step S102, the microcomputer (CPU) as the driving support control unit 5 sets the sag detection flag to OFF when the sag detection flag is ON. This is to prevent the detection state of the sag portion from being maintained even after the sag portion is detected.

In step S103, the gradient change point arrival flag and the climbing end point arrival flag in the memory 4 are set to OFF.
In step S104, the gradient change point arrival flag is confirmed. In the subsequent step S105, it is determined whether or not the gradient change point has been reached. Here, the fact that the gradient change point arrival detection flag is ON at the time of step S105 after the sag portion is detected means that the detected gradient change point is the sag portion as shown in FIGS. 3A and 3B. Is the gradient change point Pc. That is, the process of step S105 is a process for determining whether or not the gradient change point Pc has been reached.

If it is determined that the gradient change point arrival flag is not ON and the gradient change point Pc has not been reached, the process returns to step S104.
On the other hand, if it is determined that the gradient change point arrival flag is ON and the gradient change point Pc has been reached, the vehicle speed, the inter-vehicle distance, the current time, and the accelerator opening information are recorded in, for example, the memory 4 in step S106. . The information on the own vehicle speed is obtained from the vehicle speed sensor described above, and the information on the inter-vehicle distance is obtained from the result of the preceding vehicle detection process by the image processing unit 3 described above. The current time information is obtained using, for example, a time keeping function of the driving support control unit 5, and the accelerator opening information is obtained from the accelerator opening sensor described above. The information on the host vehicle speed, the inter-vehicle distance, the current time, and the accelerator opening recorded in step S106 functions as information at the time when the host vehicle reaches the gradient change point Pc constituting the sag portion.

  When the recording process of step S106 is executed, a speed recovery support related process is executed in step S107.

  By the main process as described above, the process shown in FIG. 5 and FIG. 6 as the speed recovery support related process is started in response to the host vehicle reaching the gradient change point Pc.

5 and 6 show a specific processing procedure to be executed as the speed recovery support-related processing in step S107.
In FIG. 5, first, the processes of steps S201 to S203 are processes for waiting until a predetermined time elapses from the time of arrival at the gradient change point Pc.
First, in step S201, the host vehicle speed, the inter-vehicle distance, the current time, the accelerator opening, and the brake switch state are recorded in the memory 4, for example. In step S202, an elapsed time from the point of arrival at the gradient change point Pc is calculated. This elapsed time is calculated by calculating the difference between the current time recorded in step S106 of FIG. 4 and the current time recorded in step S201.
In step S203, it is determined whether or not a predetermined time has elapsed. That is, by determining whether or not the elapsed time calculated in step S202 is equal to or greater than a predetermined value, it is determined whether or not a predetermined time has elapsed since the point of arrival at the gradient change point Pc. If it is determined that the predetermined time has not elapsed, the process returns to step S201, and the determination process of step S203 is executed again through the recording process of each information such as the vehicle speed. Thus, a loop is formed that waits until a predetermined time elapses from the point of arrival at the gradient change point Pc.

On the other hand, if it is determined in step S203 that the predetermined time has elapsed, first, whether or not the speed recovery support control should be executed based on the vehicle speed, the accelerator opening, and the presence / absence of the brake operation by the determination processing in steps S204 to S206. It is determined whether or not.
Specifically, in step S204, it is determined whether or not the vehicle speed has continued to decrease for a predetermined time from the point of arrival at the gradient change point Pc. The determination process in step S204 is performed with reference to the information on the vehicle speed sequentially recorded in the memory 4 by the process in steps S106 and S201 during a predetermined time from the time when the gradient change point Pc is reached.
If it is determined that the vehicle speed has not decreased for a predetermined time, the process is terminated.

If it is determined in step S204 that the vehicle speed has continued to decrease for a predetermined time, it is determined in step S205 whether or not there is a history that the accelerator opening decrease rate is equal to or greater than a predetermined value. That is, the accelerator opening decrease rate is predetermined during the predetermined time based on the information of the accelerator opening sequentially recorded in the memory 4 by the processing of Steps S106 and S201 during the predetermined time from the time when the gradient change point Pc is reached. It is determined whether or not there is a history exceeding the value.
If it is determined that there is a history that the accelerator decrease rate is equal to or greater than a predetermined value, the process is terminated.
Here, if the accelerator opening reduction rate is equal to or greater than a predetermined value, it is estimated that the driver suddenly opened the accelerator pedal by detecting some danger. The discrimination process in step S205 is a process for confirming the presence or absence of such a sudden release history.

If it is determined in step S205 that there is no history in which the accelerator opening reduction rate has reached or exceeded a predetermined value, it is determined in step S206 whether there is a brake ON history. That is, there is a history that the brake is turned on during the predetermined time based on the information of the brake switch state sequentially recorded in the memory 4 by the process of step S201 during the predetermined time from the time when the gradient change point Pc is reached. It is determined whether or not.
If it is determined that there is a brake ON history, the process ends.

  As can be understood from the processing of these steps S204 to S206, in the present embodiment, “the vehicle speed is not continuously decreased” “accelerator pedal is not continuously reduced for a predetermined time from the time when the vehicle reaches the gradient change point Pc. The speed recovery support control is not executed in the case of any of “there is a history of sudden release” and “there is a history of brake operation”.

If it is determined in step S206 that there is a brake ON history, the process proceeds to step S207. In step S207, it is determined whether or not a preceding vehicle exists. This process is performed based on the result of the preceding vehicle detection process described above.
If it is determined that there is no preceding vehicle, speed recovery support control A (high level) is executed in step S210. Specifically, the engine control unit 7 is instructed to set the travel mode to “power mode”, and the display control is performed so that the alarm display as “high level” is displayed on the display unit 11 (MFD). The unit 6 is instructed. Here, the alarm display as “high level” is performed by causing the MFD to display “flashing” text information such as “speed reduction”. The alerting level can be increased by the blinking display.

On the other hand, if it is determined that a preceding vehicle exists, it is determined in step S208 whether the inter-vehicle distance is greater than the predetermined inter-vehicle distance. That is, information on the inter-vehicle distance from the preceding vehicle obtained by the preceding vehicle detection process described above is acquired, and the value of the inter-vehicle distance indicated by the information on the inter-vehicle distance is a predetermined inter-vehicle distance value (for example, 100 m ) Is determined.
If it is determined that the inter-vehicle distance is greater than the predetermined inter-vehicle distance, the process proceeds to step S210 and the speed recovery support control A described above is executed.

If it is determined that the inter-vehicle distance is not greater than the predetermined inter-vehicle distance, it is determined in step S209 whether the inter-vehicle distance has been continuously increased for a predetermined time. That is, the inter-vehicle distance continuously increases during the predetermined time based on the information on the inter-vehicle distance sequentially recorded in the memory 4 by the process of step S106 or S201 during the predetermined time from the point of arrival at the gradient change point Pc. It is determined whether or not it was.
If it is determined that the inter-vehicle distance has not increased for a predetermined time, the speed recovery support control is not executed and the process ends.

  On the other hand, if it is determined that the inter-vehicle distance is continuously increasing for a predetermined time, the speed recovery support control B (weak level) is executed in step S211. Specifically, the engine control unit 7 is instructed to set the travel mode to “normal mode”, and the display control is performed so that an alarm “low level” is displayed on the display unit 11 (MFD). Instruct the unit 6. The alarm display as “low level” is performed by, for example, displaying “lit” on the MFD with text information such as “speed reduction”. By being lit, the alert level is weaker than in the blinking display.

After the speed recovery support control is executed in step S210 or step S211, the process proceeds to step S212 shown in FIG.
The process shown in FIG. 6 is a process for canceling the operation executed in association with the speed recovery support control. First, in step S212, the accelerator opening is recorded in the memory 4, for example, and in the subsequent step S213, it is determined whether or not the accelerator opening decrease rate is equal to or greater than a predetermined value. That is, the accelerator opening reduction rate is calculated using a plurality of accelerator opening values recorded within a predetermined unit time in the past based on the current time, and whether or not the calculated accelerator opening reduction rate is equal to or greater than a predetermined value. Is determined.
If it is determined that the accelerator opening decrease rate is equal to or greater than the predetermined value, a release process for the operation executed in association with the speed recovery support process control is executed in step S218. Specifically, as the release processing, the display control unit 6 is instructed to stop the alarm display while instructing the engine control unit 7 to return the traveling mode to the mode before the speed recovery support control is executed in step S210 or S211. Instructions.
After executing the release process in step S218, the process ends.

  If it is determined that the accelerator opening decrease rate is not equal to or greater than the predetermined value, after checking the brake switch state in step S214, whether or not the brake is ON in step S215, that is, whether or not the brake operation has been performed. If it is determined that the brake is ON, the release process of step S218 is executed.

On the other hand, if it is determined that the brake is not ON, after confirming the climbing end point arrival flag in step S216, it is determined whether or not the climbing is finished in step S217. That is, it is determined whether or not the uphill end point arrival flag is ON.
When it is determined that the climbing is finished, the cancellation process of step S218 is executed, and when it is determined that the climbing is not finished, the process returns to step S212.

  Through the series of processes shown in FIG. 6, the actions executed in accordance with the speed recovery support control are “the vehicle has reached the end of the climbing slope”, “the accelerator pedal has been suddenly released”, and “the brake operation has been performed”. Canceled when either condition is met.

  Here, in the above description, as an example of the speed recovery support control, the case where the same level of control can be performed when the preceding vehicle exists and when the preceding vehicle does not exist is illustrated. From the viewpoint of switching the control level of support control, the control level may be simply switched between when the preceding vehicle exists and when it does not exist. Specifically, in that case, the determination processing in steps S207 and S208 in FIG. 5 may be omitted.

  In the above description, it has been confirmed whether the speed decrease or the inter-vehicle distance tends to increase during a predetermined time after reaching the gradient change point Pc. In this way, the time after the gradient change point Pc is reached is used as a reference. Instead, a decrease in speed and an increase in the inter-vehicle distance may be confirmed during traveling a predetermined distance after reaching the gradient change point Pc.

<4. Summary>
As described above, in the present embodiment, the condition that the host vehicle speed decreases and the inter-vehicle distance tends to increase after the host vehicle passes the slope change point as the uphill starting point. When the above is satisfied, as speed recovery support control, control for adjusting the output torque to the increase side with respect to the relationship between the accelerator opening and the output torque is executed.
According to such a configuration, since the speed recovery support control is executed in consideration of the presence of the preceding vehicle, the control is performed in consideration of the surrounding traffic environment.
In addition, the control for actually recovering the speed is not the automatic adjustment of the accelerator opening or the automatic cruise control as in the conventional case, but the control for adjusting the relationship between the accelerator opening and the output torque. The driver's will intervenes and does not give the driver a sense of incongruity.
Further, since the speed recovery support control is performed when the inter-vehicle distance with the preceding vehicle is increasing, when the own vehicle speed is decreasing and the inter-vehicle distance with the preceding vehicle is decreasing, that is, the own vehicle speed When the decrease is caused by the deceleration of the preceding vehicle, the speed recovery support control is not executed. Therefore, the speed recovery support control is not executed in the case where the driver does not desire acceleration, and the driver does not feel uncomfortable in this respect.
From these points, according to the present embodiment, it is possible to realize speed recovery support for speed reduction unintended by the driver so as not to give the driver a sense of incongruity while adapting to the surrounding traffic environment.

In the present embodiment, the engine output characteristic is changed to the torque-oriented engine output characteristic as the speed recovery support control while the engine output characteristic can be changed and set stepwise according to the operation. I am doing so.
According to this, since the existing engine output characteristic adjustment function can be used for speed recovery support control, there is no need to have special control information for speed recovery support control as control information for realizing the engine output characteristics. . When the driver wants to change the engine output characteristic set by the speed recovery support control, the desired engine output characteristic can be set by operation.

Furthermore, in the present embodiment, the host vehicle speed continuously decreases and the inter-vehicle distance from the preceding vehicle continues for a predetermined time or during a predetermined distance travel after the host vehicle passes the climbing slope start point. The speed recovery support control is executed when the condition of increasing tendency is satisfied.
As a result, the driving support control is not executed when the host vehicle speed is temporarily decreased or the inter-vehicle distance from the preceding vehicle is temporarily increased. It is not preferable in terms of drivability to execute the speed recovery support control when the host vehicle speed is temporarily decreased or the inter-vehicle distance from the preceding vehicle is temporarily increased. Also, if the decrease in the vehicle speed is temporary, the possibility of inducing traffic jams is low. Therefore, it is possible to achieve appropriate control by executing the speed recovery support control when the host vehicle speed is continuously decreasing or the inter-vehicle distance from the preceding vehicle is continuously increasing.

Furthermore, in the present embodiment, the speed recovery support control is executed when the above condition is satisfied after the host vehicle passes through the gradient change point Pc constituting the sag portion.
As a result, the speed recovery support control is executed for the driving state after passing through the gradient changing point Pc constituting the sag portion, that is, the driving state in the case where the probability of occurrence of the traffic jam is high, so that the traffic jam is prevented. It is suitable for.

In addition, in the present embodiment, it is executed by the speed recovery support control when the own vehicle reaches the end point of the uphill, the brake operation is performed, or the accelerator pedal is suddenly released. Operation release processing is performed.
As a result, when there is no risk of a decrease in the vehicle speed due to the uphill, or when the driver wants to consciously decrease the vehicle speed, the operation for speed recovery support is automatically canceled. The Therefore, excessive speed recovery support is prevented, and safety is improved.

<5. Modification>
Although the embodiments according to the present invention have been described above, the present invention should not be limited to the specific examples illustrated above, and various modifications can be considered.
For example, in the description so far, the example in which the speed recovery support related process is executed in response to the arrival at the gradient change point Pc (the uphill start point constituting the sag portion) has been described. It is also possible to execute speed recovery support related processing in accordance with the arrival at the starting point of the uphill.

In addition, the arrival of the slope change point as the starting point of the uphill is detected based on the image processing based on the image captured in front of the host vehicle, specifically, the result of forming the lane model. The arrival time of can also be detected based on the result of image detection of markers provided near the road surface at the gradient change point. Alternatively, the present invention is not limited to these image processing methods. For example, position information indicating an uphill starting point is prepared in advance, and the position information is matched with current position detection information by a GPS (Global Positioning System) sensor. It is also possible to detect based on As described above, various specific methods for detecting an uphill starting point in the present invention are conceivable, and should not be limited to a specific method.
Similarly, the detection method of the sag part can be a method using a marker formed on the road surface or a method using position information in addition to the detection based on the lane model, and should be limited to a specific method. is not.

  In addition, the detection method of the preceding vehicle is not limited to the method exemplified above, and other methods such as a method using a millimeter wave radar may be employed.

  The speed recovery support control is executed only when the driver selects the “save mode” with the most fuel-efficient engine output characteristics, and when “normal mode” or “power mode” is selected. It may not be executed.

  In addition, although the case where the engine output characteristic is changed to the torque-oriented type is illustrated for the speed recovery support, the output torque may be adjusted to the increasing side by executing a shift down instead. As the engine speed increases due to the downshift, the output torque tends to increase even if the accelerator opening is the same (especially when the speed decreases due to the uphill as the subject of the present invention). In this case, the output control unit in the present invention corresponds to the transmission control unit 8. The output torque adjusting unit of the present invention may be any specific means as long as it can adjust the relationship between the accelerator opening and the output torque.

  In addition, the determination as to whether or not the inter-vehicle distance with the preceding vehicle is continuously increasing is made based on the history information of the inter-vehicle distance, but instead, the deceleration of the preceding vehicle and the reduction of the own vehicle are performed. The speed is sequentially calculated and recorded, and it is determined whether the deceleration of the host vehicle is continuously greater than the deceleration of the preceding vehicle based on the deceleration history information obtained thereby. May be. Even if such processing based on deceleration is employed, it is still determined whether or not the distance between the preceding vehicle and the preceding vehicle is continuously increasing.

  In the process of FIG. 5, when there is a history that the accelerator opening decrease rate is equal to or greater than a predetermined value, when there is a history of brake operation, the speed recovery support control is not executed. Even if there is such a history, it may be preferable to perform the speed recovery support control if the event of returning the accelerator or stepping on the brake is instantaneous. Therefore, in response to the above history, it is determined whether or not the accelerator is returned within a predetermined time and whether or not the brake is turned off within a predetermined time, respectively, and the accelerator is returned within the predetermined time. If the brake is turned off within a predetermined time, the process may proceed to step S207.

Further, in the process of FIG. 5, a situation such as a continuous decrease in the host vehicle speed or an increase in the inter-vehicle distance is confirmed only during a predetermined time from the point of arrival at the uphill starting point, and the speed recovery support control is performed based on the result. However, even after the predetermined time has elapsed from the point of arrival at the starting point of the uphill, the situation during the “predetermined time” that has been traced back from the current time is confirmed, and the speed recovery is based on the result. It is good also as what performs support control.
This is particularly effective for long climbs.

  In addition, the cancellation process of the operation executed in accordance with the speed recovery support control is performed in response to the arrival at the climbing end point. The cancellation process is performed when the inter-vehicle distance from the preceding vehicle reaches the climbing start point. It may be executed in response to returning to the inter-vehicle distance or returning to the speed at the time when the vehicle speed reaches the uphill starting point.

Moreover, although the case where the visual information presentation as a character was illustrated as an example of the speed recovery | restoration assistance by information presentation, auditory information presentation by an announcement sound etc. can also be performed, for example.
Moreover, although the example which applies this invention with respect to AT vehicle was given, this invention can be applied suitably also to MT (manual transmission mission) vehicle.

  DESCRIPTION OF SYMBOLS 1 ... Vehicle control system, 3 ... Image processing part, 3D ... Prior vehicle detection processing part, 3E ... Sag part detection processing part, 3F ... Gradient change point arrival detection processing part, 5 ... Driving assistance control part, 5A ... Speed recovery assistance Processing unit 6 ... Display control unit 7 ... Engine control unit 8 ... Transmission control unit 10 ... Sensor / operator 10A ... Vehicle speed sensor 10B ... Brake switch 10C ... Accelerator opening sensor 10D ... Mode selection switch

Claims (5)

A host vehicle speed detection unit for detecting the host vehicle speed as the traveling speed of the host vehicle;
A gradient change point detection unit that detects a gradient change point as a starting point of an uphill;
A preceding vehicle detection unit for detecting a preceding vehicle;
An output torque adjustment unit for adjusting the relationship between the accelerator opening and the output torque;
When the condition that the host vehicle speed decreases and the inter-vehicle distance tends to increase after the host vehicle passes the gradient change point is satisfied, the output torque adjusting unit is used as the speed recovery support control. And a control unit that executes control for adjusting the output torque to the increase side. The output torque adjuster is
It is possible to change and set the engine output characteristics step by step according to the operation.
The controller is
The driving support control device according to claim 1, wherein the speed recovery support control is performed by changing the engine output characteristic to a torque-oriented engine output characteristic. The controller is
A condition that the host vehicle speed continuously decreases and the inter-vehicle distance from the preceding vehicle continuously increases during a predetermined time or a predetermined distance after the host vehicle passes the gradient change point. The driving support control device according to claim 1 or 2, wherein the speed recovery support control is executed when the condition is satisfied. A sag detection unit for detecting a sag part present in front of the host vehicle;
The controller is
The driving support control according to any one of claims 1 to 3, wherein the speed recovery support control is executed when the condition is satisfied after the host vehicle passes through the slope changing point constituting the sag portion. apparatus. The gradient change point detector is
It is possible to detect the slope change point as the end point of the uphill,
The controller is
The action executed by the speed recovery support control when the own vehicle has reached the slope change point as the end point of the uphill, the brake operation is performed, or the accelerator pedal is suddenly released. The driving support control device according to any one of claims 1 to 4, wherein a release process is performed.

Images