Vehicle driving control device

Abstract

To improve avoidance effect by taking positions of a precedent vehicle and of a following vehicle into consideration at the time of executing emergency avoidance control.SOLUTION: A vehicle travelling control device has a function of executing in-lane automatic travelling, while maintaining a set vehicle speed if there is no precedent vehicle on a travelling lane of an own vehicle and while maintaining a set inter-vehicle distance if there is the precedent vehicle, and an EM function of executing emergency avoidance control including actuation of an emergency brake if it is predicted that an own vehicle collides with the precedent vehicle travelling ahead on the travelling lane of the own vehicle or an obstacle on the lane, which determines a direction of steering for avoiding on the basis of a position in a lateral direction of the precedent vehicle or the obstacle on the travelling lane of the own vehicle during execution of the EM function, and executes the steering for avoiding together with the emergency brake.SELECTED DRAWING: Figure 8

Description

[Technical Field]

[0001] The present invention relates to a vehicle cruise control device, and more particularly to an emergency avoidance function when an automatic lane keeping system is operating. [Background technology]

[0002] Various driving control systems aimed at reducing the burden on drivers and supporting safe driving are being put into practical use and international standardization is underway. For example, driving control systems such as the already-in-use Acceleration Control System (ACCS) and Lane Keeping Assist System (LKAS), as well as a combination of these, the Partially Automated In-Lane Driving System (PADS), are being put into practical use. Of these, regulations have been formulated for the Automated Lane Keeping System (ALKS), which applies to automated driving within a single lane under specific conditions, such as when the vehicle is traveling at speeds below 60 km / h and on expressways with a physical separator between the oncoming lane and other lanes.

[0003] In such an automated lane keeping system, if a serious failure occurs in the system or if the driver is unable to respond to a request to take over control, the system will switch to risk minimization control (Minimal Risk Maneuver, MRM).On the other hand, if a collision with another vehicle is predicted, emergency avoidance control (EM) will be activated, and the system will avoid the collision by slowing down at maximum deceleration or stop the vehicle in its lane.

[0004] For example, Patent Document 1 discloses that when a predetermined condition is met while the vehicle is traveling that makes it difficult for the vehicle control system or the driver to continue traveling, an automatic stopping mode is executed to stop the vehicle within a predetermined stopping area, and the lateral distance from other vehicles traveling alongside is increased. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Publication No. 2020-158090 Summary of the Invention [Problem to be solved by the invention]

[0006] However, when stopping a vehicle, the movements of the preceding and following vehicles are not taken into consideration, which means that the following vehicle cannot avoid the vehicle that has slowed down and stopped, which may result in contact or collision.

[0007] The present invention has been made in consideration of the above-described circumstances, and its purpose is to improve the avoidance effect by taking into account the positions of preceding and following vehicles when emergency avoidance control is initiated. [Means for solving the problem]

[0008] In order to solve the above problems, the present invention provides: an environmental state estimation unit including a surroundings recognition function for recognizing the current lane, adjacent lanes, other vehicles on each lane, and the surrounding environment, and a function for acquiring the current vehicle motion state; a route generation unit that generates a target route based on information acquired by the environmental state estimation unit; a vehicle control unit that performs speed control and steering control so as to make the host vehicle follow the target route; A vehicle driving control device comprising: A function that maintains the set vehicle speed when there is no preceding vehicle in the vehicle's lane, and automatically drives within the lane while maintaining the set vehicle distance when there is a preceding vehicle. An EM function that performs emergency avoidance control, including emergency braking, when a collision with a preceding vehicle or obstacle in the vehicle's lane is predicted; In those having When the EM function is activated, the lateral position of a preceding vehicle or obstacle in the vehicle's own lane However, if the vehicle is deviated to the left or right with respect to its running position, the Determine the direction of evasive steering, When the EM function is activated, if the deviation of the lateral position of the preceding vehicle or obstacle is equal to or less than a predetermined value and there is no rear vehicle in the own lane, the direction of the avoidance steering is determined to be toward the road edge, and if there is a rear vehicle in the own lane and the lateral position of the rear vehicle is deviated to either the left or right with respect to the running position of the own vehicle, the direction of the avoidance steering is determined to be opposite to the deviation of the rear vehicle, It is characterized by performing evasive steering along with emergency braking. [Effects of the Invention]

[0009] As described above, when the EM function is activated, the vehicle driving control device of the present invention determines the direction of evasive steering based on the lateral position of the preceding vehicle or obstacle that caused the EM function to be activated, and performs evasive steering together with emergency braking.Therefore, even if the braking distance for an emergency stop is insufficient, the evasive steering has the advantage of improving the possibility of avoiding a collision with the preceding vehicle. [Brief explanation of the drawings]

[0010] [Figure 1] FIG. 1 is a schematic diagram showing a vehicle cruise control system. [Figure 2] FIG. 2 is a schematic plan view showing a group of external sensors of the vehicle. [Figure 3] FIG. 1 is a block diagram showing a vehicle cruise control system. [Figure 4] FIG. 2 is a state transition diagram of control in the cruise control system. [Figure 5] 3 is a flowchart showing a control process according to an embodiment of the present invention. [Figure 6] FIG. 2 is a schematic plan view showing an example of the relative positional relationship between the host vehicle and a preceding vehicle when the EM is activated. [Figure 7] 1 is a schematic plan view showing an example of the relative positional relationship between a host vehicle and a following vehicle when an EM is activated. FIG. [Figure 8] 10 is a flowchart showing a process for determining the avoidance steering direction when the EM is activated. DETAILED DESCRIPTION OF THE INVENTION

[0011] Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In FIG. 1, a vehicle 1 equipped with a cruise control system according to the present invention includes, in addition to typical automobile components such as an engine and a body, external sensors 21 that detect the environment around the vehicle, internal sensors 22 that detect vehicle information, a group of controllers / actuators for speed control and steering control, an ACC controller 14 for controlling the distance between vehicles, an LKA controller 15 for lane keeping control, and an autonomous driving controller 10 that controls these components to perform partially automated driving within a lane (PADS), automated driving within a single lane (ALKS), and automated lane changing (PALS).

[0012] The controller / actuator group for speed control and steering control includes an EPS (electric power steering) controller 31 for steering control, an engine controller 32 for acceleration / deceleration control, and an ESP / ABS controller 33. ESP (registered trademark; Electronic Stability Program) includes ABS (anti-lock braking system) to form a stability control system (vehicle behavior stabilization control system).

[0013] The external environment sensor 21 consists of multiple detection means for inputting the presence and relative distance of road dividing lines that define the current lane and adjacent lanes, other vehicles, obstacles, people, etc. around the current vehicle as external environment data such as image data or point cloud data to the automatic driving controller 10.

[0014] 2, vehicle 1 is equipped with a millimeter-wave radar (211) and a camera (212) as forward detection means 211, 212, LIDAR (laser image detection / ranging) as front-side detection means 213 and rear-side detection means 214, and a camera (back camera) as rear detection means 215, which cover 360 degrees around the vehicle and can detect the positions and distances of vehicles and obstacles within a predetermined range in the front, rear, left and right directions of the vehicle, as well as the positions of lane markings in the vehicle's lane and adjacent lanes. Note that millimeter-wave radar (or LIDAR) can also be added as rear detection means.

[0015] The internal sensor 22 is composed of a plurality of detection means for measuring physical quantities that represent the vehicle's motion state, such as a vehicle speed sensor, a yaw rate sensor, and an acceleration sensor. As shown in FIG. 3, each measurement value is input to the autonomous driving controller 10, the ACC controller 14, the LKA controller 15, and the EPS controller 31, and is processed together with the input from the external sensor 21.

[0016] The autonomous driving controller 10 includes an environmental state estimation unit 11, a route generation unit 12, and a vehicle control unit 13, and is composed of a computer for performing the functions described below, namely, a ROM that stores programs and data, a CPU that performs arithmetic processing, a RAM that reads the programs and data and stores dynamic data and arithmetic processing results, and an input / output interface.

[0017] The environmental state estimation unit 11 acquires the absolute position of the vehicle by matching the vehicle position information obtained by a positioning means 24 such as a GPS with map information 23, and estimates the positions of the lane markings of the vehicle and adjacent lanes, and the positions and speeds of other vehicles, based on external data such as image data and point cloud data acquired by an external sensor 21. It also acquires the motion state of the vehicle from internal data measured by an internal sensor 22. It also acquires the state of the driver from a driver status monitor 25.

[0018] The route generation unit 12 generates a target route from the vehicle position to the destination estimated by the environmental state estimation unit 11. In addition, based on the adjacent lane marking positions, other vehicle positions and speeds, and the vehicle's motion state estimated by the environmental state estimation unit 11, the route generation unit 12 generates a target route from the vehicle position to the destination point during automated driving, such as lane keeping, lane changing, or course change.

[0019] The vehicle control unit 13 calculates a target vehicle speed and a target steering angle based on the target route generated by the route generation unit 12, and transmits a speed command for constant speed driving or vehicle-to-vehicle distance maintenance / following driving to the ACC controller 14, and transmits a steering angle command for route following to the EPS controller 31 via the LKA controller 15.

[0020] The vehicle speed is also input to the EPS controller 31 and the ACC controller 14. Because the steering reaction force changes depending on the vehicle speed, the EPS controller 31 refers to a steering angle-steering torque map for each vehicle speed and sends a torque command to the steering mechanism 41. The engine controller 32, the ESP / ABS controller 33, and the EPS controller 31 control the engine 42, the brakes 43, and the steering mechanism 41, thereby controlling the longitudinal and lateral movements of the vehicle 1.

[0021] (Outline of partially automated driving system within lanes) Next, we will provide an overview of the Partially Automated in-lane Driving System (PADS).

[0022] The partially automated driving system (PADS) is a system that combines an adaptive cruise control system (ACCS) and a lane keeping assistance system (LKAS), and can be executed when the ACC controller 14, which constitutes the adaptive cruise control system (ACC) together with the autonomous driving controller 10, and the LKAS controller 15, which constitutes the lane keeping assistance system (LKAS), are both operating.

[0023] At the same time as the in-lane partially automated driving system is activated, the automated driving controller 10 (route generation unit 12) generates a target route and target vehicle speed within a single lane based on external information (lane, vehicle position, position and speed of other vehicles traveling in the lane in which the vehicle is traveling and adjacent lanes) acquired by the environmental state estimation unit 11 through the external sensor 21, and internal information (vehicle speed, yaw rate, acceleration) acquired by the internal sensor 22.

[0024] The automatic driving controller 10 (vehicle control unit 13) calculates the yaw rate γ and lateral acceleration (d 2 y / dt 2 ) the vehicle speed, posture, and lateral displacement after Δt seconds are estimated from the relationship, and a steering angle command that will result in lateral displacement of yt after Δt seconds is given to the EPS controller 31 via the LKA controller 15, and a speed command that will result in speed Vt after Δt seconds is given to the ACC controller 14.

[0025] The ACC controller 14, LKA controller 15, EPS controller 31, engine controller 32, and ESP / ABS controller 33 operate independently of automatic steering, but can also be operated by command input from the automatic driving controller 10 when the partially automated driving system (PADS), automatic lane keeping system (ALKS), and partially automated lane change system (PALS) are in operation.

[0026] The ESP / ABS controller 33, which receives a deceleration command from the ACC controller 14, issues a hydraulic command to an actuator and controls the braking force of the brakes 43, thereby controlling the vehicle speed. Furthermore, the engine controller 32, which receives an acceleration / deceleration command from the ACC controller 14, controls the actuator output (throttle opening) to issue a torque command to the engine 42, thereby controlling the driving force and thereby controlling the vehicle speed.

[0027] The ACC function (ACCS) functions as a combination of hardware and software, such as a millimeter wave radar as forward detection means 211 constituting the external sensor 21, the ACC controller 14, the engine controller 32, and the ESP / ABS controller 33.

[0028] In other words, if there is no preceding vehicle, the vehicle will travel at a constant speed with the ACC set speed (set speed) as the target vehicle speed, and if the vehicle catches up with the preceding vehicle (if the preceding vehicle speed is below the ACC set speed), the vehicle will follow the preceding vehicle while maintaining a distance (set distance) according to the set time gap (time between vehicles = distance between vehicles / vehicle speed) in accordance with the speed of the preceding vehicle.

[0029] The LKA function (LKAS) detects lane markings and the vehicle's position using the environmental state estimation unit 11 of the autonomous driving controller 10 based on image data acquired by the external sensor 21 (cameras 212, 215), and performs steering control using the EPS controller 31 via the LKA controller 15 so that the vehicle can travel in the center of the lane.

[0030] That is, upon receiving a steering angle command from the LKA controller 15, the EPS controller 31 refers to a map of vehicle speed-steering angle-steering torque, issues a torque command to the actuator (EPS motor), and gives the steering mechanism 41 the target front wheel steering angle.

[0031] The partially automated driving system (PADS) is implemented by combining the longitudinal control (speed control, inter-vehicle distance control) by the ACC controller 14 and the lateral control (steering control, lane keeping control) by the LKA controller 15 as described above.

[0032] (System status monitoring) During operation of the partially automated driving system (PADS) within a lane, the environmental state estimation unit 11 constantly monitors whether the vehicle's driving state, surrounding environmental conditions, and driver state are maintained within the system's operational design domain (ODD), based on external information acquired through the external sensor 21, vehicle information acquired by the internal sensor 22, and the driver's state acquired by the driver status monitor 25.

[0033] If the environmental state estimation unit 11 determines that the system operating conditions have deviated, or if it detects an abnormality or failure in the system, and determines that automatic driving cannot be continued stably, a Transition Demand (TD) is notified to the driver.

[0034] If the driver takes over driving operations within a predetermined time (for example, 10 seconds) after the driver's takeover request (TD), the vehicle will transition from partially automated driving within the lane to manual driving. The driver's takeover is detected by a steering torque sensor and a steering wheel grip sensor. On the other hand, if the driver does not take over driving operations within the predetermined time, the Minimal Risk Maneuver (MRM) will be activated and risk minimization control will be implemented.

[0035] (Risk minimization control when operation handover is not carried out) Minimal Risk Maneuver (MRM) refers to a function that automatically transitions to a minimal risk condition when a change in the external driving environment or a system failure occurs and the driver is notified of a takeover request (TD) but is unable to take over. Specifically, it includes control (safe stop) by the autonomous driving controller 10 to decelerate and stop within the lane.

[0036] As mentioned above, the external sensor 21 is composed of multiple sensors, and the autonomous driving controller 10 is designed to be redundant so that if an abnormality occurs in any of the sensors or detection means, a minimal risk maneuver (MRM) can be performed using other sensors or detection means.

[0037] (Emergency avoidance control when a collision is predicted) On the other hand, if a collision with another vehicle is predicted for some reason while the partially automated driving system (PADS) is operating, the emergency maneuver (EM) will be activated and emergency avoidance control will be carried out. The emergency avoidance control (EM) includes the activation of automatic emergency braking (AEB) to mitigate collision damage.

[0038] That is, the environmental state estimation unit 11 constantly calculates the predicted time to collision (TTC) based on information (inter-vehicle distance, relative speed) of the preceding vehicle (or obstacle) detected by the external sensor 21 and the vehicle speed of the vehicle itself acquired by the internal sensor 22, and when it is determined that there is a high possibility of collision, such as when the predicted time to collision is less than a predetermined value, it issues a brake request (hydraulic command) to the actuator of the brake 43 and performs automatic braking (automatic emergency braking).

[0039] (Outline of partially automated driving system within lanes) Next, we will explain the outline of the Automatically Lane Keeping System (ALKS) assuming a situation where a vehicle is operating in partially automated driving mode (PADS) on a highway with a median strip.

[0040] The Automated Lane Keeping System (ALKS) is a system that combines an Acceleration Control System (ACCS) and a Lane Keeping Assist System (LKAS), similar to the Partially Automated Driving System (PADS), and is executed when the ACC controller 14 that constitutes the Acceleration Control System (ACCS) and the Lane Keeping Assist System (LKAS) are both operating together with the autonomous driving controller 10, but can only be executed at speeds of 60 km / h or less.

[0041] When the automatic lane keeping system (ALKS) is operating, the vehicle maintains a single lane and automatic driving is performed. In addition to the above, the automatic lane keeping system (ALKS) can be executed when the driver status monitor 25 confirms that the driver is ready to take over driving in response to a takeover request, and the driver is not required to pay close attention to the driving situation as long as the driver is seated in the driver's seat and has their seatbelt fastened.

[0042] Because the minimum speed on expressways is set at 50 km / h, if a vehicle is following a vehicle ahead using partially automated driving systems (PADS) and the expressway becomes congested and the vehicle's speed drops below 50 km / h, or if the vehicle catches up with a vehicle ahead that is traveling at less than 50 km / h due to congestion, the vehicle will switch from partially automated driving systems (PADS) to automated lane keeping systems (ALKS).

[0043] 4 shows the state transition of the control in the automated lane keeping system (ALKS). Even when the automated lane keeping system (ALKS) is operating (100), the environmental state estimation unit 11 constantly monitors the vehicle's driving state, the surrounding environmental conditions, and the driver's state. If it determines that the system activation conditions are not met or if a system fault (excluding a serious malfunction, which will be described later) is detected, the system notifies the driver of a request to take over (TD) (120). If the driver takes over driving operations within a predetermined time (for example, 10 seconds), the system transitions from automated lane keeping driving to manual driving (140).

[0044] On the other hand, if the driving operation is not taken over within a predetermined time, the Minimal Risk Maneuver (MRM) is activated and the risk minimization control (130) is executed. Note that if the environmental state estimation unit 11 determines that a serious malfunction has occurred in the system (such as a drop in engine oil pressure, an increase in engine water temperature, or a brake system abnormality that could cause an accident or fire) while the Automated Lane Keeping System (ALKS) is in operation, the operation takeover request (TD) is not made, and the Minimal Risk Maneuver (MRM) is immediately activated and the risk minimization control (130) is executed.

[0045] Furthermore, if a collision is predicted for some reason while the Automated Lane Keeping System (ALKS) is operating (100), such as another vehicle cutting in, a sudden deceleration or collision of a preceding vehicle, or an obstacle (falling object), and the conditions for operating the emergency avoidance control are met, the Emergency Maneuver (EM) is activated and the Automatic Emergency Braking (AEB) is executed as the emergency avoidance control (100).

[0046] In addition, the automated driving systems described above are capable of being overridden by driver intervention, not only when the automated lane keeping system (ALKS) is in operation, but also when the motorway risk minimization control (MRM) or emergency avoidance control (EM) is in operation. In other words, when an override is performed by the driver through acceleration / deceleration intervention (accelerator OR, brake OR) or steering intervention (steering OR), each of the automated driving functions described above is stopped and the system transitions to manual driving by the driver.

[0047] As described above, automatic emergency braking (AEB) is performed when emergency avoidance control (EM) is activated, but the braking distance may be insufficient depending on the activation situation, road surface conditions, etc. Even in such cases, collision damage can be expected to be mitigated, but the possibility of collision avoidance can be increased by performing avoidance steering while taking into account the driving positions (lateral positions) of the preceding vehicle (causing vehicle) and the following vehicle in the lane.

[0048] (Improved emergency avoidance control) Therefore, the automatic driving controller 10 according to the present invention constantly monitors the driving positions of the preceding vehicle (causing vehicle) and the following vehicle in order to perform avoidance steering simultaneously with automatic emergency braking (AEB) when emergency avoidance control (EM) is activated.

[0049] That is, the environmental state estimation unit 11 constantly detects the lateral position y2 (FIG. 6) of the leading vehicle 2 within the lane, as well as the lane markings and the vehicle's own position, based on image data acquired by the external sensor 21 (cameras 212, 215), and further constantly detects the lateral position y4 (FIG. 7) of a following vehicle 4 if it is present within a predetermined distance behind the vehicle's own lane.

[0050] 6, the lateral position y2 of the preceding vehicle 2 is detected as the lateral deviation amount (relative deviation amount) and the direction of deviation, either left or right, of the center 2c of the preceding vehicle 2 relative to the center line 212c of the forward detection area corresponding to the traveling direction of the vehicle 1. The lateral position of the preceding vehicle 2 can also be detected based on the lateral distances y2R, y2L from the lane markings 5R, 5L to the preceding vehicle 2.

[0051] On the other hand, as shown in Fig. 7, when a rear vehicle 4 is present within a predetermined distance behind the own vehicle lane, the lateral position y4 of the rear vehicle 4 is detected as the lateral deviation amount (relative deviation amount) and the deviation direction, either left or right, of the center 4c of the rear vehicle 4 relative to the center line 215c of the rear detection area of ​​the vehicle 1. The lateral position y4 of the rear vehicle 4 can also be detected based on the lateral distances y4R, y4L from the lane markings 5R, 5L to the rear vehicle 4. At night, the center 4c can be detected from the left and right headlights of the rear vehicle 4.

[0052] The specified distance behind the vehicle in the own lane is set based on the braking distance at maximum deceleration and the free running distance (reaction distance of the vehicle behind + braking recovery distance) at the same speed as the vehicle behind, assuming that the vehicle behind 4 is following the vehicle behind 1 at the same speed. However, if a distance measurement means (such as millimeter wave radar) is added as a rear detection means, the specified distance behind the vehicle behind 4 may be set based on the estimated vehicle speed of the vehicle behind 4.

[0053] Furthermore, the environmental state estimation unit 11 constantly detects obstacles such as fallen objects and stopped vehicles ahead in the vehicle lane based on image data acquired by the external sensor 21 (camera 212), and when an obstacle ahead is detected and emergency avoidance control (EM) is activated, the lateral position and width of the obstacle to be avoided are acquired in the same way as for the preceding vehicle described above.

[0054] Furthermore, the environmental state estimation unit 11 constantly monitors the presence of adjacent lanes and effective road shoulders that can serve as evacuation spaces, based on the detection information of the external sensor 21. Note that an effective road shoulder is, for example, a shoulder with a pavement structure that is 1.75 m or wider, such as those typically found on expressways, and does not include protected road shoulders without a pavement structure.

[0055] When the emergency avoidance control (EM) is activated, the automatic emergency braking (AEB) is activated and the avoidance steering is executed as follows.

[0056] Fig. 8 is a flowchart showing the avoidance direction determination when emergency avoidance control (EM) is activated, and corresponds to step 113 in Fig. 5. When emergency avoidance control (EM) is activated (step 112), it is first determined whether the lateral position (2c) of the preceding vehicle 2 is deviated (y2) to the left or right with respect to the traveling position (212c) of the vehicle 1 (step 1131).

[0057] If the lateral position (2c) of the preceding vehicle 2 is deviated (y2) to either the left or right relative to the traveling position (212c) of the vehicle 1 (step 1131; YES), the direction of the avoidance steering is determined to be in the opposite direction to the deviation (anti-deviation direction) (step 1141).

[0058] For example, as shown in Fig. 6, when the preceding vehicle 2 is deviated to the left relative to the vehicle 1, corrective steering is performed to the right, which ensures a relatively wide avoidance width within the lane. The steering amount of this corrective steering can be set to a steering amount that imparts a lateral displacement equivalent to the difference between the width of the vehicle 1 and the deviation y2 of the preceding vehicle 2 within the braking distance due to the automatic emergency braking, and a corrective steering angle command is given to the EPS controller 31 via the LKA controller 15.

[0059] On the other hand, when the emergency avoidance control (EM) is activated, if it is determined that the lateral deviation (y2) of the leading vehicle 2 is less than a predetermined value and that a sufficient avoidance width cannot be secured within the lane to the side of the leading vehicle 2 (FIG. 8, step 1131; NO), and if a rear vehicle 4 is present (step 1132; YES), the lateral position (y4) of the rear vehicle 4 is referenced (step 1133), and if the rear vehicle 4 is deviated (y4) to either the left or right (step 1133; YES), the direction of the avoidance steering is determined to be in the opposite direction to the deviation (counter-deviation direction) (step 1142).

[0060] For example, as shown in FIG. 7, if the rear vehicle 4 is deviated to the left relative to the vehicle 1, corrective steering is performed to the right, in the opposite direction to the deviation, so that the rear vehicle 4 can avoid the host vehicle 1 with less steering and the avoidance width of the rear vehicle 4 is increased.

[0061] Furthermore, if the lateral deviation (y4) of the rear vehicle 4 is below a predetermined value and the evasive action of the rear vehicle 4 cannot be identified (step 1133; NO), a check is made to see if there is an adjacent lane or a shoulder on the road edge side based on the detection information of the external sensor 21 (step 1134), and if there is an adjacent lane or an effective shoulder on either the left or right side of the own lane (step 1134; YES), the direction of evasive steering is determined to be on the opposite side (towards the central reservation) from the adjacent lane or shoulder in order to widen the evasive width of the rear vehicle 4 on those sides (step 1143).

[0062] Furthermore, if there is no rear vehicle 4 (FIG. 8, 1132; NO), or if there is a rear vehicle 4 but there is no adjacent lane or valid shoulder (step 1134; NO), the direction of the evasive steering is determined to be toward the road edge within the lane so that an evasive width for the rear vehicle 4 is secured on the side opposite the road edge (step 1144).

[0063] Through the process described above, the direction and steering amount of avoidance steering when emergency avoidance control (EM) is activated are determined, and when emergency avoidance control (EM) is activated, avoidance steering is executed simultaneously with activation of automatic emergency braking (AEB). Because this avoidance steering is basically executed within the lane, the steering amount is minimal, and even if avoidance steering is executed simultaneously with braking at maximum deceleration, the effect on the posture of vehicle 1 is small, and this can be handled by behavior stabilization control by ESP / ABS controller 33.

[0064] (Control flow when the automatic lane keeping system is operating) Next, the control flow (FIG. 5) during operation of the automatic lane keeping system will be described.

[0065] (1) Automatic Lane Keeping System (ALKS) operation When the vehicle is following a preceding vehicle using partially automated driving within a lane (PADS driving) and the vehicle speed drops below 60 km / h, the system switches to the automated lane keeping system (ALKS) (step 100).

[0066] (2) Collision possibility determination While the Automated Lane Keeping System (ALKS) is operating, collision possibility determination is always performed (step 101). That is, if the collision prediction time (TTC) becomes equal to or less than a predetermined value due to sudden braking of a preceding vehicle, sudden cutting in of another vehicle, or the appearance of a stopped vehicle or obstacle due to a preceding vehicle changing lanes (steerage avoidance), and it is determined that there is a collision possibility, the system transitions to emergency avoidance control (EM) (step 110).

[0067] (3) Emergency Avoidance Control When the emergency avoidance control (EM) is started, the collision determination flag is set (step 111) and the automatic emergency brake (AEB) is activated as emergency avoidance control (step 112). At the same time, the avoidance steering direction is determined based on the lateral position of the preceding vehicle (or forward obstacle) that caused the emergency avoidance control to be activated, and, if a rear vehicle is present within a predetermined distance behind, the lateral position of that vehicle (step 113; Figure 8, steps 1131 to 1144).

[0068] (4) Turn signal operation The direction indicator corresponding to the determined avoidance steering direction is activated to notify the vehicle behind of the steering intention (step 114).

[0069] (5) Avoidance steering and maximum deceleration braking Corrective steering is performed in the direction of the steering wheel determined within the lane in which the vehicle is traveling, and at the same time, the maximum deceleration (5 m / s 2 Automatic emergency braking is performed (step 114).

[0070] (6) Determining whether an override is present during EM operation The determination of whether an override is present or absent continues even while emergency avoidance control (automatic emergency braking) is in operation (step 116), and if steering intervention equal to or greater than a predetermined steering override threshold, accelerator operation intervention equal to or greater than a predetermined accelerator override threshold, or brake operation intervention equal to or greater than a predetermined brake override threshold is detected, the automated lane keeping system (ALKS) stops and the vehicle transitions to manual driving (step 140).

[0071] (5) Emergency avoidance control completion determination It is determined whether the emergency avoidance control (EM) has been completed based on the vehicle state and the surrounding environment (step 117). That is, if the imminent risk of a collision has disappeared (due to an emergency stop or a change in the surrounding environment) or if the system has been deactivated by the driver, it is determined that the emergency avoidance control has been completed, the hazard lights are flashed (step 118), and the automated lane keeping system (ALKS) is stopped (step 140).

[0072] (6) Serious failure determination While the Automated Lane Keeping System (ALKS) is operating, the vehicle's self-diagnosis function constantly determines whether a serious malfunction has occurred (step 102). Serious malfunctions include a drop in engine oil pressure, an increase in engine water temperature, and a brake system abnormality, which can lead to an accident or fire. If a serious malfunction is determined to have occurred, a serious malfunction flag is set (step 131), and the system transitions to risk minimization control (MRM) (130).

[0073] (7) System startup conditions not met or failure determination While the automated lane keeping system (ALKS) is operating, the environmental state estimation unit 11 constantly determines whether the vehicle's driving state and the surrounding environmental conditions are being maintained within the operational design domain (ODD) of the system, the driver status monitor 25 determines whether the driver is ready to take over driving, and the vehicle's self-diagnosis function determines whether any of the components of the automated lane keeping system have a failure or malfunction (step 103). In addition to road conditions and vehicle speed, the ODD of the automated lane keeping system includes environmental conditions such as strong winds, and system failures and external sensor failures also fall under these conditions.

[0074] If the system activation conditions are not met or a malfunction is determined, a warning to stop the automated lane keeping system (ALKS) and a request to take over (TD) are sent (step 120), and a predetermined time (for example, 10 seconds) is started to count (step 121). (8) Driving transfer decision In step 122, if the takeover of driving operations is confirmed by detecting steering torque or the like within a predetermined time (e.g., 10 seconds), the automated lane keeping system (ALKS) is stopped and the system transitions to manual driving (step 140). On the other hand, if the takeover of driving operations is not confirmed within the predetermined time, the system transitions to risk minimization control (MRM) (130).

[0075] (9) Risk minimization control When the system shifts to risk minimization control (MRM), the hazard lights are turned on (step 132) and at the same time, the minimal risk maneuver (MRM) is activated (step 133). The automatic driving controller 10 maintains the lane while decelerating at a predetermined rate (for example, 4.0 m / s 2 The vehicle is decelerated to a stop by the following control.

[0076] (10) Determining whether or not an override is present during MRM operation The determination of whether or not an override has occurred continues even while the risk minimization control (MRM) is operating (step 134). If a steering intervention equal to or greater than a predetermined steering override threshold, an accelerator operation intervention equal to or greater than a predetermined accelerator override threshold, or a brake operation intervention equal to or greater than a predetermined brake override threshold is detected, the automated lane keeping system (ALKS) is stopped and the vehicle transitions to manual driving (step 140).

[0077] (11) Risk minimization control completion determination It is determined whether or not the risk minimization control (MRM) is complete based on the vehicle state (step 135). That is, if the system is deactivated or the system has stopped the vehicle, it is determined that the risk minimization control is complete, and the automatic lane keeping system (ALKS) is stopped (step 140), the hazard lamps are kept flashing, and all other vehicle systems are stopped.

[0078] (Action and effect) As described above in detail, the vehicle driving control device according to the present invention determines the direction of avoidance steering based on the lateral position (y2) of the preceding vehicle 2 (or obstacle) in the own lane when emergency avoidance control (EM) is activated, and performs avoidance steering together with emergency braking, thereby offering the advantage that even if the braking distance for an emergency stop is insufficient due to an unforeseen event, the possibility of avoiding a collision can be improved by avoidance steering.

[0079] For example, as shown in Figure 6, if the lateral position 2c of the preceding vehicle 2 is displaced y2 to the left relative to the running position (212c) of vehicle 1, by performing the minimum avoidance steering given by the difference between the vehicle width and the displacement y2 to the right (opposite displacement direction) where a relatively wide avoidance width can be secured, in a situation where the vehicle is closest to the preceding vehicle 2, as shown by symbol 1', it is possible to avoid a collision with the preceding vehicle 2 even if the braking distance is insufficient.

[0080] In this case, since the avoidance steering is performed within the lane in which the vehicle 1 is traveling, there is no need to consider the movement of vehicles in adjacent lanes, and there is also the advantage that control can be performed immediately regardless of the movement of vehicles in adjacent lanes.

[0081] At this time, if another vehicle is traveling behind vehicle 1, emergency braking will be performed automatically or manually in response to the activation of vehicle 1's emergency brakes, but since vehicle 1 moves to the right of leading vehicle 2 by evasive steering, an evasive width will be secured on the left side of vehicle 1, i.e., on the side of leading vehicle 2.

[0082] When emergency avoidance control (EM) is activated, a time gap of about twice the time gap between vehicle 1 and leading vehicle 2 is secured between leading vehicle 2 and the following vehicle, so if the following vehicle can avoid a collision with vehicle 1 immediately ahead, it is highly likely to be able to brake and stop before reaching the stopping position of leading vehicle 2. Therefore, the above-mentioned avoidance steering is also advantageous in that it can prepare an avoidance width for the following vehicle to reduce the possibility of vehicle 1 being rear-ended by the following vehicle.

[0083] In addition, when the emergency avoidance control (EM) is activated, if the lateral displacement y2 of the leading vehicle 2 is less than a predetermined value, the direction of avoidance steering is determined based on the lateral position of the rear vehicle, thereby reducing the possibility of vehicle 1 being rear-ended by the rear vehicle.

[0084] For example, as shown in Figure 7, when the leading vehicle 2 is located directly in front of the vehicle 1, if the lateral position 4c of the rear vehicle 4 is displaced y4 to the left relative to the running position 215c of the vehicle 1, the rear vehicle 4 can be steered to the right (opposite the displacement direction) to ensure a relatively wide avoidance width, thereby reducing the possibility of the vehicle 1 being rear-ended by the rear vehicle 4 (4'), and increasing the possibility of avoiding a collision with the leading vehicle 2' by performing evasive steering.

[0085] In addition, when the emergency avoidance control (EM) is activated, if the lateral deviation y4 of the rear vehicle 4 is below a predetermined value, a check is made to see if there is an adjacent lane or effective shoulder on the road edge side of the own lane that can provide an avoidance space for the rear vehicle 4, and if there is an adjacent lane or effective shoulder that can provide an avoidance space for the rear vehicle 4, avoidance steering is performed in the opposite direction (towards the central reservation) to increase the avoidance width for the rear vehicle 4 and reduce the possibility of vehicle 1 being rear-ended by the rear vehicle 4.

[0086] On the other hand, if there is no adjacent lane or effective shoulder that can provide avoidance space for the rear vehicle 4, by performing avoidance steering toward the road edge, the avoidance width for the rear vehicle 4 can be increased toward the adjacent lane on the opposite side of the road edge (the side of the central reservation), thereby reducing the possibility of vehicle 1 being rear-ended by the rear vehicle 4.

[0087] (Other Examples) In the above embodiment, the case where avoidance steering is performed within the lane in which the vehicle 1 is traveling when the emergency avoidance control (EM) is activated has been mainly described, but avoidance steering may also be performed across the dividing lines 5L, 5R between the vehicle 1 and an adjacent lane or road shoulder. Therefore, avoidance steering may be performed by at least partially moving the vehicle 1 from the lane in which the vehicle 1 is traveling to the adjacent lane or road shoulder. In particular, if the relative lateral deviation of the leading vehicle or the rear vehicle is equal to or less than a predetermined value, avoidance steering may also be performed by changing lanes to the adjacent lane or road shoulder, provided that it is confirmed that no other vehicles or obstacles exist within a predetermined range before or after the adjacent lane or road shoulder.

[0088] In addition, in the above embodiment, the control state transition during operation of the Automated Lane Keeping System (ALKS) has been mainly described, but the avoidance steering control according to the present invention may also be executed when Emergency Avoidance Control (EM) is activated during operation of other automated driving functions, such as a Partially Automated Driving System (PADS) or a Partially Automated Lane Changing System (PALS).

[0089] Although several embodiments of the present invention have been described above, it should be noted that the present invention is not limited to the above-described embodiments, and various modifications and variations are possible within the scope of the present invention. [Explanation of symbols]

[0090] 10 Autonomous Driving Controller 11 Environmental state estimation unit 12 Route generation unit 13 Vehicle control unit 14 ACC controller 15 LKA controller 21 External Sensor 22 Internal Sensors 25 Driver Status Monitor 31 EPS controller 32 Engine Controller 33 ESP / ABS controller 34 Manual steering (steering wheel)

Claims

1. an environmental state estimation unit including a surroundings recognition function for recognizing the current lane, adjacent lanes, other vehicles on each lane, and the surrounding environment, and a function for acquiring the current vehicle motion state; a route generation unit that generates a target route based on information acquired by the environmental state estimation unit; a vehicle control unit that performs speed control and steering control so as to make the host vehicle follow the target route; A vehicle driving control device comprising: A function that maintains the set vehicle speed when there is no preceding vehicle in the vehicle's lane, and automatically drives within the lane while maintaining the set vehicle distance when there is a preceding vehicle. An EM function that executes emergency avoidance control, including the application of emergency brakes, when a collision with a preceding vehicle or obstacle in the vehicle's lane is predicted; In those having When the EM function is activated, if the lateral position of a preceding vehicle or an obstacle in the own lane is deviated to either the left or right with respect to the traveling position of the own vehicle, the direction of avoidance steering is determined to be opposite to the deviation; When the EM function is activated, if the deviation of the lateral position of the preceding vehicle or obstacle is equal to or less than a predetermined value and no rear vehicle is present in the own lane, the direction of the avoidance steering is determined to be toward the road edge, and if a rear vehicle is present in the own lane and the lateral position of the rear vehicle is deviated to either the left or right with respect to the running position of the own vehicle, the direction of the avoidance steering is determined to be opposite to the deviation of the rear vehicle, A vehicle driving control device that performs avoidance steering in conjunction with emergency braking.

2. A vehicle driving control device as described in claim 1, characterized in that if a rear vehicle is present in the vehicle's lane but the deviation of the rear vehicle's lateral position is less than a predetermined value and there is no adjacent lane or shoulder on the road edge side, the direction of the evasive steering is determined to be toward the road edge side, and if there is an adjacent lane or shoulder on the road edge side, the direction of the evasive steering is determined to be toward the central reservation strip side.

3. 3. The vehicle driving control device according to claim 1, wherein the avoidance steering when the EM function is activated is performed within the lane in which the vehicle is traveling.

4. 4. A vehicle driving control device according to claim 1, wherein the avoidance steering when the EM function is activated includes at least a partial movement from the lane in which the vehicle is traveling to an adjacent lane or a shoulder of the road.

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