Vehicle control devices

Abstract

The present invention provides a vehicle control device capable of reliable automatic control, such as when an oncoming vehicle is overtaking. The vehicle control device comprises: an information acquisition unit that acquires surrounding information, including the relative speed between the vehicle and a front obstacle, the distance in the direction of travel, and the overlap ratio of the front obstacle with respect to the vehicle; a determination unit that, during travel, determines whether to execute automatic braking control using the collision margin time and overlap ratio calculated based on the relative speed and distance in the direction of travel; and an automatic braking control unit that performs braking control based on the determination made by the determination unit. Furthermore, when the overlap ratio of the front obstacle increases, the automatic braking control unit initiates braking control at an earlier time than when the overlap ratio does not increase.

Description

Technical Field

[0001] The present invention relates to a vehicle control device that performs automatic braking control and / or automatic steering control, etc. Background Art

[0002] In recent years, systems that use stereo cameras or the like to recognize obstacles and perform control for collision avoidance, such as automatic braking control and automatic steering control, have become widespread in automobiles.

[0003] Patent Document 1 describes a technology that determines whether to perform an evasive turn based on the overlap ratio of an oncoming vehicle that has crossed out of its lane. This technology satisfies a evasive turn condition when the overlap ratio is between 0 and 50%, but evasive turns are not performed at overlap ratios above this level to avoid a sideways collision.

[0004] Prior art literature

[0005] Patent Literature

[0006] Patent Document 1: Japanese Patent Application Publication No. 2018-97648 Summary of the Invention

[0007] Technical issues

[0008] However, it is conceivable that a two-wheeled vehicle approaching from the opposite lane may cross into the host vehicle's lane in order to overtake. In this case, the two-wheeled vehicle accelerates to overtake, increasing its relative speed while creating a relatively small overlap ratio with the host vehicle. This small overlap ratio may delay the collision risk assessment, and the increased relative speed may make collision avoidance using automatic braking difficult.

[0009] Therefore, an object of the present invention is to more appropriately execute control for collision avoidance even in such a situation.

[0010] Technical Solution

[0011] The vehicle control device of the present invention comprises: an information acquisition unit, which acquires surrounding information including the relative speed and the distance in the direction of travel between the vehicle and a front obstacle, and the overlap rate of the front obstacle relative to the vehicle; a determination unit, which, during driving, makes an execution determination of automatic braking control using a collision margin time calculated based on the relative speed and the distance in the direction of travel, and the overlap rate; and an automatic braking control unit, which performs braking control based on the execution determination of the determination unit, and performs processing to advance the start time of braking control of the automatic braking control unit when the overlap rate increases compared to when the overlap rate does not increase.

[0012] When the overlap rate of an oncoming vehicle, for example, a vehicle that becomes a front obstacle, increases, this means that the oncoming vehicle crosses the oncoming lane into the lane on the host vehicle's side in order to overtake or the like.

[0013] It should be noted that the traveling direction distance refers to the distance between the host vehicle and the obstacle ahead in the traveling direction.

[0014] The process of advancing the start timing of the braking control refers to a process of starting the braking control earlier than when the overlap ratio does not increase, when all conditions except the overlap change amount are the same.

[0015] In the vehicle control device, when the overlap ratio increases, the collision margin time for determining the start timing of the braking control may be corrected to a value that makes it easier to determine the start of the braking control than the actual collision margin time.

[0016] The collision margin time is the time until collision, calculated using the relative speed and the distance in the travel direction. Therefore, the collision margin time can be used to determine whether to start braking control. By correcting the collision margin time used for the braking control start determination, the braking control start determination can be made earlier.

[0017] In the vehicle control device, it is considered that when the overlap ratio increases, the correction is performed so that the relationship between the collision margin time and the relative speed at the time of determining the start of the braking control becomes the relationship represented by a quadratic curve.

[0018] Correction is performed to achieve a relationship in which, for example, the collision margin time is relatively greatly reduced even at a low relative speed.

[0019] In addition, another vehicle control device of the present invention includes: an information acquisition unit, which acquires surrounding information including the relative speed and the distance in the direction of travel between the vehicle and the obstacle in front, and the overlapping rate of the obstacle in front with respect to the vehicle; a determination unit, which, during driving, uses the collision margin time calculated based on the relative speed and the distance in the direction of travel, and the overlapping rate to perform an execution determination of automatic braking control; and an automatic braking control unit, which performs braking control based on the automatic braking control determination of the determination unit, and performs processing to advance the end time of the braking control based on the automatic braking control unit when the overlapping rate decreases compared to when the overlapping rate does not decrease.

[0020] When the overlap ratio of an oncoming vehicle, for example, a front obstacle, decreases, this means that the oncoming vehicle has crossed from the oncoming lane to the host vehicle's lane for overtaking and then returned to the oncoming lane.

[0021] The process of advancing the start timing of the braking control is a process of ending the braking control earlier than when the overlap ratio does not decrease, when all conditions except the overlap change amount are the same.

[0022] In addition, another vehicle control device of the present invention includes: an information acquisition unit, which acquires surrounding information including the relative speed and the distance in the traveling direction between the vehicle and the obstacle in front, and the overlapping rate of the obstacle in front with respect to the vehicle; a determination unit, which, during driving, uses the collision margin time calculated based on the relative speed and the distance in the traveling direction and the overlapping rate to perform execution determinations of automatic braking control and automatic steering control; an automatic braking control unit, which performs braking control based on the execution determination of the automatic braking control by the determination unit; and an automatic steering control unit, which performs steering control based on the execution determination of the automatic steering control by the determination unit, and performs processing that facilitates the transfer from the braking control of the automatic braking control unit to the steering control of the automatic steering control unit when the overlapping rate decreases compared to when the overlapping rate does not decrease.

[0023] Automatic brake control refers to, for example, so-called AEB (Autonomous Emergency Braking), which performs brake control for avoiding a collision.

[0024] Automatic steering control is, for example, so-called AES (Autonomous Emergency Steering), and performs steering control and necessary braking control for avoiding a collision.

[0025] The process of facilitating the transition from the braking control of the automatic braking control unit to the steering control of the automatic steering control unit is a process of terminating braking and transitioning to the steering control earlier than when the overlap ratio does not decrease, when all conditions except the overlap variation are the same.

[0026] Technical Effects

[0027] According to the present invention, the timing of starting or ending automatic braking control or shifting to automatic steering control is adjusted based on the change in the overlap ratio, thereby realizing automatic control suitable for situations such as overtaking in the opposite lane. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 This is a block diagram of a vehicle control device according to an embodiment of the present invention.

[0029] Figure 2 This is a block diagram showing the functional configuration of a driving assistance control unit according to the embodiment.

[0030] Figure 3It is an explanatory diagram of a situation in which control according to the embodiment is performed.

[0031] Figure 4 This is a flowchart of the processing of AEB control and AES control according to the embodiment.

[0032] Figure 5 It is an explanatory diagram of correction for advancing the brake intervention timing in the embodiment.

[0033] Figure 6 It is an explanatory diagram of the overlap ratio correction coefficient according to the embodiment.

[0034] Explanation of symbols

[0035] 1 Vehicle Control Unit, 2 Imager, 3 Image Processing Unit, 4 Memory, 5 Driving Assistance Control Unit, 5a Information Acquisition Unit, 5b AEB Control Unit, 5c AES Control Unit, 5d Determination Unit, 6 Display Control Unit, 7 Engine Control Unit, 8 Transmission Control Unit, 9 Brake Control Unit, 10 Sensor Operation Device, 10a Vehicle Speed ​​Sensor, 10b Engine Speed ​​Sensor, 10c Accelerator Position Sensor, 10d Steering Angle Sensor, 10e Yaw Rate Sensor, 10f G Sensor, 10g Brake Switch, 10h Millimeter-Wave Radar, 11 Display Unit, 12 Engine-Related Actuator, 13 Transmission-Related Actuator, 14 Brake-Related Actuator, 15 Steering Control Unit, 16 Steering-Related Actuator, 17 Bus, 30 Host Vehicle, 31 Oncoming Vehicle, 32 Oncoming Overtaking Vehicle, 40 Driving Lane, 41 Driving Lane, 42 Oncoming Lane DETAILED DESCRIPTION

[0036] <Configuration of vehicle control system>

[0037] Figure 1 1 is a block diagram showing the general configuration of a vehicle control device 1 according to an embodiment of the present invention. Figure 1 In FIG. 1 , only the configuration of the main components of the present invention is extracted and shown in the configuration of the vehicle control device 1 .

[0038] The vehicle control device 1 is configured to include a shooting unit 2, an image processing unit 3, a memory 4, a driving assistance control unit 5, a display control unit 6, an engine control unit 7, a transmission control unit 8, a brake control unit 9, a sensor operating device 10, a display unit 11, an engine-related actuator 12, a transmission-related actuator 13, a brake-related actuator 14, a steering control unit 15, a steering-related actuator 16, and a bus 17.

[0039] Image processing unit 3 is comprised of a microcomputer equipped with, for example, a CPU (Central Processing Unit), ROM (Read Only Memory), and RAM (Random Access Memory). Image processing unit 3 performs predetermined image processing related to recognition of the external environment based on image data captured by imaging unit 2 in the direction of travel of the vehicle (in this example, the front). Image processing unit 3 performs image processing using memory 4, such as nonvolatile memory.

[0040] Two camera units are provided in the imaging unit 2. Each camera unit is configured to include a camera optical system and an imaging element such as a CCD (Charge Coupled Device) and / or a CMOS (Complementary Metal Oxide Semiconductor). The camera optical system forms an image of a subject on an imaging surface of the imaging element, and an electrical signal corresponding to the amount of received light is obtained on a pixel-by-pixel basis.

[0041] Each camera unit is configured to perform distance measurement based on a so-called stereo imaging method. Furthermore, the electrical signals obtained by each camera unit undergo A / D conversion and / or predetermined correction processing, and are then supplied to the image processing unit 3 as digital image signals (captured image data) representing a predetermined brightness level on a pixel-by-pixel basis.

[0042] The image processing unit 3 performs various image processing operations based on the image data obtained through stereoscopic imaging. It identifies forward information such as 3D object data and / or white line data in front of the vehicle and estimates the vehicle's travel path based on this identified information. Furthermore, the image processing unit 3 detects preceding and / or oncoming vehicles in the vehicle's travel path based on the identified 3D object data.

[0043] Specifically, the image processing unit 3 performs the following processing based on the stereoscopic image data. First, for each pair of image data, distance information is generated based on the deviation (parallax) between corresponding positions using the principle of triangulation. Then, the distance information is grouped and compared with pre-stored three-dimensional road shape data and / or three-dimensional object data to extract white line data, sidewall data such as guardrails and curbs along the road, three-dimensional object data such as vehicles, stop lines, traffic signals, intersections, crosswalks, lanes (driving lanes or oncoming lanes, etc.).

[0044] Furthermore, the image processing unit 3 estimates the vehicle's path based on white line data and / or sidewall data, and extracts (detects) any three-dimensional objects that are located in the vehicle's path and accelerate at a predetermined speed in a direction substantially similar to the vehicle's path as preceding vehicles. When a preceding vehicle is detected, the image processing unit 3 calculates the inter-vehicle distance (= the inter-vehicle distance from the vehicle), the relative speed (= the magnitude of the change in the inter-vehicle distance), the preceding vehicle speed (= the relative speed + the vehicle's speed), and the preceding vehicle acceleration (= the derivative of the preceding vehicle speed) as preceding vehicle information.

[0045] It should be noted that the vehicle speed is the running speed of the vehicle detected by a vehicle speed sensor 10 a described later.

[0046] Of course, the image processing unit 3 detects not only the preceding vehicle but also obstacles and / or oncoming vehicles ahead. In particular, oncoming vehicles crossing into the vehicle's lane are also detected as obstacles.

[0047] The image processing unit 3 also calculates the overlap ratio between the host vehicle and the obstacle ahead. The obstacle ahead may be a preceding vehicle, but also includes objects such as an oncoming vehicle entering the lane in which the host vehicle is traveling.

[0048] The overlap ratio is an indicator that indicates the positional relationship between the vehicle and the obstacle ahead in the lateral direction relative to the vehicle's direction of travel. For example, assuming the overlap ratio is 100% at the center of the vehicle in the lateral direction, the value representing the relative lateral position of the obstacle ahead with respect to the vehicle is used.

[0049] Furthermore, the image processing unit 3 also calculates the distance in the traveling direction between the host vehicle and the obstacle ahead.

[0050] The traveling direction distance is the distance between the host vehicle and the obstacle ahead in the traveling direction (longitudinal direction).

[0051] Thus, the image processing unit 3 can recognize surrounding objects based on the image captured by the imaging unit 2 and can also recognize the movement of the objects.

[0052] Furthermore, the image processing unit 3 calculates various kinds of surrounding environment information as described above for each frame of captured image data, and stores (holds) the calculated information one by one in the memory 4 .

[0053] The driving assistance control unit 5 is composed of a microcomputer having, for example, a CPU, ROM, RAM, etc., and the driving assistance control unit 5 performs various control processes for driving assistance (hereinafter referred to as "driving assistance control processes") based on the results of image processing performed by the image processing unit 3 stored in the memory 4, and / or detection information, operation input information, etc. obtained by the sensor operating device 10.

[0054] The driving assistance control unit 5 is connected to each of the control units, namely the display control unit 6, the engine control unit 7, the transmission control unit 8, and the brake control unit 9, which are also composed of microcomputers, via a bus 17, and can communicate data among these control units. The driving assistance control unit 5 instructs the necessary control units among these control units to perform driving assistance operations.

[0055] Assumed driving assistance control executed by the driving assistance control unit 5 are, for example, lane keeping control, automatic braking control (AEB) and / or automatic steering control (AES) for reducing collision damage, and adaptive cruise control (ACC) with inter-vehicle distance control.

[0056] It should be noted that AEB is a control that avoids collisions particularly through braking control (brake control), while AES is a control that avoids collisions through steering control and necessary braking control.

[0057] When the target acceleration and / or target stopping position (target deceleration) is set according to the driving assistance control being executed, the driving assistance control unit 5 calculates the requested torque for the engine control unit 7, the brake fluid pressure for the brake control unit 9, and the gear ratio for the transmission control unit 8 based on this information and outputs them.

[0058] Furthermore, when the target steering angle is set, the driving assistance control unit 5 instructs the steering control unit 15 on the steering amount corresponding to the target steering angle.

[0059] The driving assist operation is realized by operating the engine control unit 7 , the brake control unit 9 , the transmission control unit 8 , and the steering control unit 15 based on the requested torque, brake fluid pressure, gear ratio, steering amount, and the like.

[0060] The sensor operating device 10 generally represents the various sensors and operating elements installed in the vehicle. The sensors included in the sensor operating device 10 include: a vehicle speed sensor 10a that detects the vehicle's speed (vehicle speed); an engine speed sensor 10b that detects the engine's rpm; an accelerator opening sensor 10c that detects the accelerator opening based on the amount the accelerator pedal is depressed; a steering angle sensor 10d that detects the steering angle; a yaw rate sensor 10e that detects the yaw rate; a G-sensor 10f that detects acceleration; a brake switch 10g that turns on and off based on whether the brake pedal is operated; and a millimeter-wave radar 10h that can detect surrounding conditions.

[0061] The millimeter wave radar 10h can measure the distance, speed, and angular velocity to a distant object, and thus can detect, for example, the speed, acceleration, and steering conditions such as left and right turns of the preceding and / or oncoming vehicles.

[0062] It should be noted that, although not shown in the figure, the sensor operating part device 10 also has other sensors such as an intake air volume sensor for detecting the amount of intake air to the engine, a throttle opening sensor for detecting the opening of the throttle valve, a water temperature sensor for detecting the cooling water temperature indicating the engine temperature, an external air temperature sensor for detecting the air temperature outside the vehicle, and a slope sensor for detecting the slope of the vehicle's driving route. The throttle valve is installed in the intake passage and adjusts the amount of intake air supplied to each cylinder of the engine.

[0063] In addition, as operating elements, there are: an ignition switch for indicating the start / stop of the engine; an operating element for performing operations related to the above-mentioned driving assistance control; a selection lever for selecting the automatic transmission mode / manual transmission mode in the automatic transmission and / or indicating upshifting / downshifting in the manual transmission mode; and a display switching switch for switching the display information in the MFD (Multi Function Display) provided in the display unit 11 described later, etc.

[0064] The display unit 11 generally represents various instruments such as a speedometer and / or tachometer, an MFD, and other display devices for providing information to the driver, which are located in an instrument panel located in front of the driver. The MFD can display various information such as the total distance traveled by the vehicle and / or the outside temperature, instantaneous fuel consumption, etc., simultaneously or in a switching manner.

[0065] The display control unit 6 controls the display operation of the display unit 11 based on detection signals from predetermined sensors in the sensor operation device 10 and / or operation input information performed through the operating elements. For example, based on instructions from the driving assistance control unit 5, predetermined caution information can be displayed on the display unit 11 (for example, in a predetermined area of ​​the MFD) as part of driving assistance.

[0066] The engine control unit 7 controls various actuators provided as the engine-related actuators 12 based on detection signals from predetermined sensors in the sensor operation device 10 and / or operation input information through operating elements.

[0067] As the engine-related actuator 12 , 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.

[0068] For example, the engine control unit 7 controls the start / stop of the engine based on the operation of the ignition switch. Furthermore, the engine control unit 7 controls the fuel injection timing, fuel injection pulse width, throttle opening, and the like based on detection signals from predetermined sensors such as the engine speed sensor 10b and / or the accelerator opening sensor 10c.

[0069] In addition, the engine control unit 7 calculates a target throttle opening based on the requested torque and the gear ratio of the automatic transmission, for example, according to a mapping, and controls the throttle actuator (engine output control) based on the calculated throttle opening. The requested torque is the torque calculated and output by the driving assistance control unit 5 based on the target acceleration.

[0070] The transmission control unit 8 controls various actuators provided as transmission-related actuators 13 based on detection signals from predetermined sensors in the sensor-operator device 10 and / or operation input information through operating elements.

[0071] As the transmission-related actuator 13 , for example, an actuator for performing shift control of an automatic transmission is provided.

[0072] For example, when the automatic shift mode is selected by the selector lever, the transmission control unit 8 outputs a shift signal to the actuator according to a predetermined shift pattern to control the shifting. Alternatively, when the manual shift mode is selected, the transmission control unit 8 outputs a shift signal to the actuator based on an upshift / downshift instruction from the selector lever to control the shifting.

[0073] When the automatic transmission is a CVT (Continuously Variable Transmission), control for continuously changing the speed ratio is performed as the speed change control when the automatic speed change mode is set.

[0074] The brake control unit 9 controls various actuators provided as the brake-related actuator 14 based on detection signals from predetermined sensors in the sensor operation device 10 and / or operation input information through an operating element.

[0075] As the brake-related actuator 14 , various brake-related actuators such as a hydraulic control actuator for controlling the output hydraulic pressure from the brake booster to the master cylinder and / or the hydraulic pressure in the brake fluid pipe are provided.

[0076] For example, the brake control unit 9 controls the hydraulic control actuator based on the hydraulic pressure instruction information output from the driving assistance control unit 5 to brake the vehicle.

[0077] The steering control unit 15 obtains a required torque steering based on the target steering amount given by, for example, the driving assistance control unit 5 , and controls the steering-related actuator 16 to achieve the required automatic steering.

[0078] exist Figure 2 3 shows the functional configuration of the driving assistance control unit 5, which is provided by software, for example, specifically for performing the processing of this embodiment. The driving assistance control unit 5 includes an information acquisition unit 5a, an AEB control unit (automatic braking control unit) 5b, an AES control unit (automatic steering control unit) 5c, and a determination unit 5d.

[0079] The information acquisition unit 5a acquires information about obstacles around the vehicle. Specifically, the information acquisition unit 5a uses information about the surrounding environment recognized by the image processing unit 3 and information detected by the millimeter-wave radar 10h to acquire or interpret the surrounding environment, obstacles (including preceding and / or oncoming vehicles), and road conditions.

[0080] In particular, the information acquisition unit 5a also acquires or calculates the relative speed between the host vehicle and a front obstacle (eg, a preceding vehicle and / or an oncoming vehicle), the distance in the traveling direction, and the overlap ratio of the front obstacle with respect to the host vehicle.

[0081] During travel, the determination unit 5d uses the TTC (Time to Collision) calculated from the relative speed and the distance in the travel direction, and the overlap ratio, to determine whether to execute AES control (automatic braking control). Note that TTC (Time to Collision) is the value obtained by dividing the distance in the travel direction by the relative speed.

[0082] Furthermore, the determination unit 5 d uses the collision margin time and the overlap ratio to determine whether to execute AES control (automatic steering control) (including determination of switching from AEB control to AES control) during driving.

[0083] The AEB control unit 5 b has a function of performing automatic braking control based on obstacle information to prevent a collision with an obstacle during travel.

[0084] The AES control unit 5 c has a function of automatically performing steering and, if necessary, automatic braking control in order to prevent a collision with an obstacle during travel based on obstacle information.

[0085] <Handling Example>

[0086] The processing of the embodiment implemented in the vehicle control device 1 having the above configuration will be described.

[0087] The processing of the embodiment assumes a situation in which an oncoming vehicle, particularly due to overtaking in the oncoming lane, crosses into the driving lane of the host vehicle, and implements appropriate AEB control and / or AES control in such a situation.

[0088] Figure 3 The diagram shows a host vehicle 30 traveling in a driving lane 41 and opposing vehicles 31 and 32 traveling in opposite directions in an opposing lane 42. The host vehicle 30 is traveling on a road having two lanes, the driving lane 40 and the driving lane 41.

[0089] At this moment, for example, an oncoming vehicle 32, which is a motorcycle, wants to overtake the oncoming vehicle 31, which is a passenger car. In the following description, the oncoming vehicle 32 will be referred to as an "oncoming overtaking vehicle 32."

[0090] In order to overtake the oncoming vehicle 31, the oncoming overtaking vehicle 32 first moves out of the oncoming lane 42 to the driving lane 41. The oncoming overtaking vehicle 32 then continues to accelerate while moving out and overtakes the oncoming vehicle 31, and then returns to the oncoming lane 42 which is the original lane.

[0091] In the description, the period during which the oncoming overtaking vehicle 32 crosses the travel lane 41 is referred to as period TS1, and the period during which the oncoming overtaking vehicle 32 returns to the original lane is referred to as period TS2.

[0092] In such a situation where overtaking is being performed, the oncoming overtaking vehicle 32 is recognized as an obstacle ahead of the host vehicle 30 .

[0093] Here, during the period TS1 during which the oncoming overtaking vehicle 32 crosses into the driving lane 41 of the host vehicle 30, the overlap ratio of the oncoming overtaking vehicle 32 with respect to the host vehicle 30 gradually increases. Furthermore, at this time, since the oncoming overtaking vehicle 32 is assumed to be accelerating in order to overtake, the relative speed between the host vehicle 30 and the oncoming overtaking vehicle 32 increases.

[0094] This situation increases the risk of collision for the host vehicle 30. However, the driver of the oncoming overtaking vehicle 32 drives to return to their original lane after overtaking and also avoids collision with the host vehicle 30 (the lateral position of the oncoming overtaking vehicle 32 rarely reaches directly opposite the host vehicle 30). Therefore, although the overlap ratio gradually increases, it often remains relatively small. When the overlap ratio is low, the risk of collision may not be determined, and the start of AEB control may be delayed.

[0095] Furthermore, during period TS2, when oncoming overtaking vehicle 32 has passed oncoming vehicle 31 and is returning to oncoming lane 42, the overlap ratio of oncoming vehicle 32 with host vehicle 30 gradually decreases. While this situation reduces the risk of collision, braking control of host vehicle 30 can negatively impact passenger comfort. Furthermore, the risk of a rear-end collision with a following vehicle cannot be eliminated.

[0096] Therefore, in the present embodiment, even in such a situation where overtaking occurs on the opposite lane side, appropriate driving assistance control can be performed.

[0097] exist Figure 4 2 shows an example of processing performed by the driving assistance control unit 5 .

[0098] This processing is done using Figure 2 This is an example of a process of the driving assistance control unit 5 executed by using the functions of the information acquisition unit 5a, the AEB control unit 5b, the AES control unit 5c, and the determination unit 5d.

[0099] The driving assistance control unit 5 repeatedly executes the following operations while the vehicle 30 is traveling: Figure 4 processing.

[0100] In step S101, the driving assistance control unit 5 acquires information about the surrounding environment. Specifically, the position and relative speed of an obstacle ahead of the host vehicle 30 in the driving lane 41 are acquired. The position of the obstacle ahead is determined by both its longitudinal position (measured as the distance in the obstacle's travel direction as viewed from the host vehicle 30) and its lateral position (measured as the overlap direction).

[0101] In step S102 , the driving assistance control unit 5 determines whether the TTC exceeds a predetermined threshold value th1 .

[0102] TTC is the margin time until a collision, which is calculated using the longitudinal position (distance in the travel direction) and relative speed of a front obstacle.

[0103] The threshold value th is a threshold value for determining whether to activate the AEB control or the AES control.

[0104] It should be noted that the threshold value th may be common to the AEB control and the AES control, or may be set individually for the AEB control and the AES control.

[0105] Since AES control also includes whether it is possible to safely avoid obstacles using steering and braking as a working condition, it also confirms, for example, the relationship between the width of the driving lane 41 and the overlap rate, the condition of the driving lane 40, the condition of surrounding vehicles and / or obstacles, etc.

[0106] Regarding AES control, the TTC confirmation mentioned here is used to confirm whether the TTC is in a state where it should operate when other conditions are met.

[0107] Furthermore, although it is possible to confirm whether the AEB control is in a situation where it should be activated based on TTC, it is also possible to confirm other conditions.

[0108] In step S102 , the threshold th may be set to be common for AEB control and AES control to determine whether TTC meets the operating conditions. For example, the threshold th may be compared with the threshold th1 for AEB control and with the threshold th2 for AES control to make a determination.

[0109] exist Figure 4 In the processing example, the above various conditions are simplified. In step S102, although it is determined in terms of TTC whether at least one of the AEB control and the AES control is in operation, various examples can actually be considered based on the operating algorithms of the AEB control and the AES control.

[0110] If the TTC is greater than the threshold value th (if the collision margin time is sufficiently long), the driving assistance control unit 5 proceeds to step S112, stores the obstacle overlap ratio and lateral position data, and returns to the processing state. In other words, at this point in time, the vehicle has not yet entered a state of performing braking control and / or steering control as part of AEB or AES control.

[0111] It should be noted that by storing the overlap ratio in step S112, it is possible to confirm the change in the overlap ratio of the obstacle ahead. The increase in the overlap ratio is a situation where the obstacle ahead enters the driving lane 41 of the vehicle 30, that is, Figure 3 The overlap ratio decreases and changes can be judged as a situation where the front obstacle leaves the driving lane 41 of the vehicle 30, that is, Figure 3 The situation in which the oncoming overtaking vehicle 32 returns to the original oncoming lane 42 as in the period TS2 is shown.

[0112] If it is determined in step S102 at a certain point in time that TTC>threshold th is not satisfied, the driving assistance control unit 5 proceeds to step S103 and determines to enter the activation state of AEB control and AES control.

[0113] Then, in step S104, the driving assistance control unit 5 determines the state of the front obstacle. Here, the relative speed between the front obstacle and the host vehicle 30 is compared with the speed of the host vehicle 30 (host vehicle speed), and the acceleration of the target front obstacle (target acceleration) is determined.

[0114] If the relative speed is greater than the vehicle speed and the target acceleration is greater than 0, the driving assistance control unit 5 proceeds to step S108 . If these conditions are not met, the driving assistance control unit 5 proceeds to step S105 .

[0115] When relative speed>host vehicle speed and target acceleration>0, it can be estimated that the target obstacle ahead is an oncoming vehicle and is accelerating.

[0116] The process proceeds to step S105 if the relative speed is not greater than the vehicle speed, or if the target acceleration is not greater than 0. In these cases, the target obstacle ahead is determined to be the preceding vehicle.

[0117] In this case, the driving assistance control unit 5 then calculates parameters for AEB control or AES control corresponding to the preceding vehicle in step S106. For example, for AEB control, the braking intervention timing is determined and, if necessary, the deceleration corresponding to the target stopping position is calculated as a parameter. For AES control, the steering intervention timing is determined and, if necessary, the steering amount, steering direction, deceleration, and other parameters are calculated as parameters.

[0118] In step S107 , the driving assistance control unit 5 performs braking control based on AEB control or steering control and braking control based on AES control based on the determination and / or parameter setting in step S106 , thereby performing braking or steering corresponding to the preceding vehicle, for example.

[0119] In step S104 , when relative speed>host vehicle speed and target acceleration>0 and the process proceeds to step S108 , the driving assistance control unit 5 determines that the target front obstacle is the oncoming overtaking vehicle 32 (a vehicle attempting to overtake the oncoming vehicle 31 ).

[0120] In this case, in step S109, the driving assistance control unit 5 checks the actual overlap ratio of the target front obstacle with respect to the host vehicle 30. This can be determined using the information stored in the previous step S112. It should be noted that the "actual overlap ratio" is the actual overlap ratio and is used to distinguish it from the corrected overlap ratio described later.

[0121] Here, when the actual overlap ratio increases (the amount of change is +), the oncoming overtaking vehicle 32 crosses into the driving lane 41 of the host vehicle 30 , which is shown as a period TS1 .

[0122] In this case, the driving assistance control unit 5 proceeds to step S110 and performs processing to advance the braking intervention timing. Specifically, the braking intervention timing under AEB control is advanced compared to the braking intervention timing under normal control.

[0123] exist Figure 5 In FIG. 1 , the horizontal axis shows the relative speed, and the vertical axis shows the TTC for brake intervention determination.

[0124] The TTC for brake intervention determination is a TTC used to determine the brake intervention timing, and is usually the above-mentioned TTC.

[0125] The brake intervention timing under AEB control, that is, the time to start braking, can be mainly determined by TTC. Then, during AEB control, when TTC becomes less than a predetermined value, it is determined that it is the brake intervention timing.

[0126] Here, in step S110, the driving assistance control unit 5 corrects the TTC itself, for example, by making the TTC with respect to the relative speed a smaller value as shown by the dotted line.

[0127] After correcting the TTC for brake intervention determination in this manner, the driving assistance control unit 5 proceeds to step S106 to calculate parameters for AEB control.

[0128] In step S106 , whether or not it is the brake intervention timing is also determined. However, since the TTC for brake intervention determination is corrected (to a shorter time value than the original value), it is more likely to be determined as the brake intervention timing.

[0129] It should be noted that the corrected TTC used in step S110 is used only for determining the timing of brake engagement. In step S106, the TTC is also used to calculate the target stopping position and / or parameters such as the brake fluid pressure corresponding to the target stopping position, but the TTC used at this time is the original, uncorrected TTC.

[0130] Thereafter, the driving assistance control unit 5 performs AEB control (or AES control) in step S107 .

[0131] It should be noted that although it is assumed that after the TTC for brake engagement determination is corrected in step S110, the process continues to proceed to step S110 during period TS1. However, the actual TTC at that point in time is corrected each time to obtain the TTC for brake engagement determination, thereby determining the timing of brake engagement. However, since the correction value is not required for determination once brake engagement has already begun, the correction calculation can be omitted even when the process proceeds to step S110.

[0132] On the other hand, the case where the actual overlap ratio change amount is not > 0 in step S109 , that is, the case where the actual overlap ratio decreases, for example, is a case where the oncoming overtaking vehicle 32 attempts to return to the original lane (oncoming lane 42 ), as shown in period TS2 .

[0133] In this case, the driving assistance control unit 5 proceeds to step S111 and corrects the actual overlap ratio based on the amount of change in the lateral position of the target front obstacle.

[0134] It should be noted that there may be a case where the actual change in the overlap ratio is 0. Figure 6 In the example, when the change in the actual overlap ratio is 0, it is considered that the actual overlap ratio has stopped increasing and the oncoming overtaking vehicle 32 has started to return to the original lane (considered equivalent to a decrease in the change) and the process proceeds to step S111.

[0135] However, it can also be considered that when the actual amount of change in the overlap ratio is 0, it is considered equivalent to the case where the actual amount of change in the overlap ratio increases and the process proceeds to step S110.

[0136] Figure 6 The horizontal axis shows the change in the lateral position of the target obstacle ahead, and the vertical axis shows the overlap correction coefficient. Specifically, the overlap correction coefficient is selected based on the change in lateral position, and the current overlap ratio (actual overlap ratio) is corrected to obtain a corrected overlap ratio. For example, the overlap correction coefficient is selected so that the greater the change in the lateral position of the target obstacle ahead, the smaller the overlap ratio.

[0137] The overlap ratio correction in step S111 facilitates the termination of AEB control. A low overlap ratio reduces the likelihood of collision, making it easier to determine that AEB control brake intervention is unnecessary. Therefore, correcting the overlap ratio to minimize the risk of collision makes it easier to determine that AEB control has terminated.

[0138] Furthermore, the overlap ratio correction in step S111 also facilitates initiation of AES control. A high overlap ratio makes it difficult to determine whether AES steering is enabled, even if steering is attempted within the same lane, as there is no available position for avoidance. In contrast, a low overlap ratio makes it easier to determine whether steering within the lane is enabled, thus easily meeting the AES steering intervention conditions. Therefore, correcting for a low overlap ratio makes AES steering intervention easier.

[0139] After correcting the overlap ratio in this manner, the driving assistance control unit 5 proceeds to step S106 to calculate parameters for the AEB control or the AES control.

[0140] During the AEB control process, the AEB control termination determination is also performed in step S106, but in this case, the corrected overlap ratio is referenced. The corrected overlap ratio makes it easier to determine that the target is not a front obstacle, thereby making it easier to determine the AEB control termination.

[0141] Furthermore, using the corrected overlap ratio for AES control facilitates the decision to initiate control. Specifically, if the corrected overlap ratio is set lower than the actual overlap ratio, it is easier to determine that a collision is easily avoidable using steering, making it easier to determine when to initiate steering intervention using AES control. For example, if a steering intervention decision is made during AEB control, switching to AES control is possible.

[0142] Note that, in this case, the corrected overlap ratio corrected in step S111 is used only for the AEB termination determination and the AES-based steering intervention start determination.

[0143] The actual overlap ratio is used to calculate parameters for the actual steering intervention, for example, to calculate a target steering angle or the like.

[0144] Thereafter, in step S107 , the driving assistance control unit 5 performs braking intervention based on the AEB control or steering intervention based on the AES control, etc., using the parameter calculation in step S106 .

[0145] Furthermore, when the driving assistance control unit 5 determines that the AEB is terminated, it terminates the AEB control in step S107 .

[0146] Furthermore, when the driving assistance control unit 5 determines that the AES steering intervention has started, it executes steering control and the like based on the AES control in step S107 .

[0147] Furthermore, when the driving assistance control unit 5 has performed the determination of the end of the AEB control and the start of the steering intervention by the AES control, it switches from the AEB control to the steering intervention by the AES control in step S107 .

[0148] <Effects of implementation>

[0149] As described above, the vehicle control device 1 of the embodiment includes: an information acquisition unit 5a that acquires surrounding information including the relative speed, travel distance, and overlap ratio of the front obstacle with the host vehicle 30; a determination unit 5d that determines whether to execute automatic braking control during driving using the collision margin time and overlap ratio calculated based on the relative speed and travel distance; and an AEB control unit 5b (automatic braking control unit) that performs braking control based on the execution determination made by the determination unit 5d. Furthermore, when the overlap ratio increases, the AEB control unit 5b performs processing to advance the timing of brake intervention (the start time of braking control) compared to when the overlap ratio does not increase (step S110).

[0150] For example, if an oncoming overtaking vehicle 32, such as a two-wheeled vehicle approaching from the oncoming lane 42, moves into the driving lane 41 of the host vehicle 30 in order to overtake, the oncoming overtaking vehicle 32 accelerates, and the relative speed between the host vehicle 30 and the oncoming overtaking vehicle 32 increases. In such a case, there may be a case where the overlap ratio is relatively small, so there is a possibility that the AEB braking intervention will be delayed. In the embodiment, it is noted that in this case, the overlap ratio is small but increasing. If Figure 4 If such a phenomenon is detected in the process of the brake control, the start time of the brake control is advanced in step S110. Thus, the possibility of avoiding the collision caused by the overtaking vehicle 32 can be improved.

[0151] Furthermore, in the embodiment, as the overlap ratio increases, the TTC (Time Before Collision) used to determine the timing of brake intervention (the start of brake control) is corrected to a value that makes it easier to determine the start of brake intervention compared to the actual TTC. Since brake intervention determination is primarily based on the TTC, correcting the TTC used for brake intervention determination can advance the brake intervention timing. Specifically, by shortening the TTC, the AEB control system can be operated earlier than usual. This allows the brake intervention timing to be advanced as the overlap ratio increases, while maintaining the same standard AEB control algorithm.

[0152] Note that such TTC correction targets only the TTC used for determining the brake intervention timing. The TTC used in the subsequent calculation of AEB control parameters and AES control parameters can be used to calculate appropriate parameters by using uncorrected values.

[0153] In the embodiment, when the overlap ratio increases, the relationship between the TTC for determining the braking intervention time and the relative speed changes from Figure 5 Correction is performed so that the linear relationship shown by the solid line becomes the relationship shown by the quadratic curve shown by the dotted line.

[0154] Specifically, when the overlap ratio increases, the TTC value is significantly shortened (corrected toward a time margin before collision) even at a relatively low relative speed. This TTC correction allows for early braking intervention.

[0155] Especially when the relative speed is high, since the initial TTC is short, the start of the braking intervention is determined early even without a major correction. However, when the relative speed is relatively low and the TTC is long, the braking intervention timing may be delayed (even if there is enough time for normal collision avoidance, it is considered as a delay in processing the oncoming overtaking vehicle 32). Figure 5By making such correction, the handling for the oncoming overtaking vehicle 32 is appropriate regardless of the relative speed.

[0156] The vehicle control device 1 of the embodiment performs processing to advance the end timing of the braking control by the AEB control unit 5 b when the overlap ratio decreases, compared to when the overlap ratio does not decrease (step S111 ).

[0157] For example, if an oncoming overtaking vehicle 32, such as a two-wheeled vehicle approaching from the oncoming lane 42, crosses into the host vehicle's lane 41 to overtake and then returns to the oncoming lane 42, the risk of collision is reduced. In this situation, continued braking control would affect passenger comfort due to unnecessary braking action and increase the risk of rear-end collisions with following vehicles due to excessive braking. Therefore, if overtaking is completed and a collision with the oncoming overtaking vehicle 32 is avoided, AEB control is terminated early. This improves comfort and safety against rear-end collisions.

[0158] During driving, the determination unit 5d of the vehicle control device 1 of the embodiment uses the collision margin time and overlap ratio calculated based on the relative speed and the distance in the travel direction to determine whether to execute AEB control or AES control. Furthermore, the vehicle control device 1 includes an AEB control unit 5b that performs braking control based on the determination unit 5d's determination of whether to execute automatic braking control, and an AES control unit 5c that performs steering control based on the determination unit 5d's determination of whether to execute automatic steering control. In this case, when the overlap ratio decreases, a process that facilitates the transition from AEB control to AES control is performed (step S111), compared to when the overlap ratio does not decrease.

[0159] For example, if an oncoming overtaking vehicle 32, such as a two-wheeled vehicle approaching from the oncoming lane 42, crosses into the host vehicle's lane 41 to overtake and then returns to the oncoming lane 42, the risk of collision is reduced and the likelihood of avoiding the collision through steering is increased. Therefore, AES transition is performed early. This also makes it possible to avoid the collision through steering. Furthermore, early switching from AEB control to AES control means an early transition from braking-based avoidance to primarily steering-based avoidance, and this is also related to minimizing emergency braking.

[0160] In addition, the overlap ratio is used to estimate the situation in which the oncoming overtaking vehicle 32 returns to the original lane (oncoming lane 42) after overtaking, and control is performed accordingly. Therefore, steering avoidance and deceleration corresponding to the action of the oncoming overtaking vehicle 32 returning to the original lane can be performed.

[0161] It should be noted that, although the overlap ratio is corrected, the steering amount and steering direction may also be corrected.

[0162] The configuration and processing examples of the embodiment are just an example. Figure 1 、 Figure 2 Example of configuration and / or Figure 4 Various modifications are considered for the processing examples.

[0163] exist Figure 4 In the processing of , although it is described that both AEB control and AES control are performed, a processing example of only AEB control or a processing example of only AES control can also be considered.

Claims

1. A vehicle control device, characterized in that: have: an information acquisition unit that acquires surrounding information including a relative speed and a distance in a traveling direction between the host vehicle and a front obstacle, and an overlap ratio of the front obstacle with respect to the host vehicle; a determination unit that determines whether to execute automatic braking control during travel by using a collision margin time calculated based on the relative speed and the distance in the traveling direction and the overlap ratio; and an automatic brake control unit that performs brake control based on the execution determination of the determination unit, The information acquisition unit stores the overlap ratio within a predetermined period and calculates an overlap ratio change amount. The determination unit performs processing to advance the start timing of the braking control by the automatic braking control unit when the overlap ratio change amount is greater than zero compared to when the overlap ratio change amount is not greater than zero. When the overlap ratio change amount is not greater than zero, the determination unit determines the start time of the braking control based on an actual collision margin time. When the overlap ratio change amount is greater than zero, the determination unit determines the start timing of the braking control based on the corrected collision margin time corrected to a value that makes it easier to make a braking control start determination than the actual collision margin time.

2. The vehicle control device according to claim 1, wherein: The vehicle control device performs the correction so that the corrected collision margin time becomes a value such that the relationship between the corrected collision margin time and the relative speed is represented by a quadratic curve.

3. A vehicle control device, characterized in that: have: an information acquisition unit that acquires surrounding information including a relative speed and a distance in a traveling direction between the host vehicle and a front obstacle, and an overlap ratio of the front obstacle with respect to the host vehicle; a determination unit that determines whether to execute automatic braking control during travel by using a collision margin time calculated based on the relative speed and the distance in the traveling direction and the overlap ratio; and an automatic brake control unit that performs brake control based on the execution determination of the determination unit, The information acquisition unit stores the overlap ratio within a predetermined period and calculates an overlap ratio change amount. The determination unit performs processing to advance the end timing of the braking control by the automatic braking control unit when the overlap ratio change amount is not greater than zero, compared to when the overlap ratio change amount is greater than zero. When the overlap ratio change amount is greater than zero, the determination unit determines the end time of the braking control based on the actual overlap ratio. When the overlap ratio change amount is not greater than zero, the determination unit determines the end timing of the braking control based on the overlap ratio corrected to a value that makes it easier to determine the end of the braking control than the actual overlap ratio.

4. A vehicle control device, characterized in that: have: an information acquisition unit that acquires surrounding information including a relative speed and a distance in a traveling direction between the host vehicle and a front obstacle, and an overlap ratio of the front obstacle with respect to the host vehicle; a determination unit that, during travel, determines whether to execute automatic braking control and automatic steering control using a collision margin time calculated based on the relative speed and the distance in the traveling direction and the overlap ratio; an automatic braking control unit that performs braking control based on the automatic braking control execution determination made by the determination unit; and an automatic steering control unit that performs steering control based on the automatic steering control execution determination made by the determination unit, The information acquisition unit stores the overlap ratio within a predetermined period and calculates an overlap ratio change amount. The determination unit performs processing that makes it easier to determine whether to start steering control by the automatic steering control unit when the overlap ratio change amount is not greater than zero than when the overlap ratio change amount is greater than zero. When the overlap ratio change is greater than zero, the determination unit determines the start of the steering control based on the actual overlap ratio. When the overlap ratio change is not greater than zero, as the processing, the determination unit determines the start of the steering control based on the corrected overlap ratio that is corrected to a value that makes it easier to make a start determination of the steering control than the actual overlap ratio.

5. The vehicle control device according to claim 3 or 4, characterized in that: The vehicle control device selects an overlap ratio correction coefficient and performs correction so that the corrected overlap ratio becomes a value that decreases as the amount of change in the lateral position of the front obstacle increases.

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