Vehicle driving control device

Abstract

To provide a vehicle travel control device which allows intervention of emergency steering control at appropriate timing when emergency brake control is performed.SOLUTION: A travel_ECU 22 calculates a prediction travel distance Dp to a time when a relative speed with an obstacle becomes 0 by secondary brake control during execution of the secondary brake control being strong brake control, permits steering intervention for avoiding collision with the obstacle when the prediction travel distance Dp is longer than a relative distance with the obstacle, calculates a collision prediction time TTCaes to a time of collision with the obstacle in the operation of the secondary brake control, and executes emergency steering control for avoiding collision with the obstacle when the steering intervention is permitted and the collision prediction time becomes equal to or less than a time threshold Tth.SELECTED DRAWING: Figure 5

Description

[Technical field]

[0001] The present invention relates to a vehicle travel control device capable of performing emergency brake control and steering control to avoid a collision with an obstacle. [Background technology]

[0002] In recent years, in vehicles such as automobiles, driving control devices have been put into practical use to assist the driver in driving operations, with the aim of reducing the burden of driving operations on the driver and improving safety. In this type of driving control device, various technologies have been developed for a driving control mode that performs steering assistance control and acceleration / deceleration control on the premise of the driver's proactive driving operation, and a driving control mode for driving the vehicle without the need for the driver's driving operation (so-called automatic driving mode) (for example, see Patent Document 1).

[0003] The driving control by the driving control device is basically realized by providing an adaptive cruise control (ACC) function, an active lane keep centering (ALKC) control function, etc. By using such driving control, the vehicle can automatically travel along the driving lane while maintaining the distance to the preceding vehicle.

[0004] In addition, in driving control devices, a technology has been put into practical use in which, when a driving environment recognition device using autonomous sensors such as cameras and radar recognizes an obstacle such as a vehicle or pedestrian in front of the vehicle, emergency braking (AEB (Autonomous Emergency Braking): collision damage mitigation brake) control is performed against the obstacle, and the vehicle is decelerated until the relative speed between the vehicle and the obstacle becomes "0".

[0005] Furthermore, in driving control devices, technology has been put into practical use that performs emergency steering (AES (Autonomous Emergency Steering)) control to avoid a collision with an obstacle when it is determined that a collision with the obstacle cannot be avoided by emergency braking control. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] JP 2019-172113 A Summary of the Invention [Problem to be solved by the invention]

[0007] Incidentally, in emergency steering control for avoiding a collision with an obstacle, it is desirable to suppress unnecessary operations and early operations as much as possible, based on the idea that driving operations by the driver should take priority.

[0008] However, as described above, if emergency steering control is intervened at the point when it is determined that a collision with an obstacle cannot be avoided by emergency braking control, there is a risk that emergency steering control will be intervened prematurely even though there is room for the driver to steer.

[0009] The present invention has been made in consideration of the above circumstances, and has an object to provide a vehicle driving control device that can intervene emergency steering control at an appropriate timing when emergency brake control is performed. [Means for solving the problem]

[0010] A vehicle driving control device according to one aspect of the present invention includes an autonomous sensor that recognizes an obstacle ahead of a host vehicle, a relative speed calculation means for calculating a relative speed between the host vehicle and the obstacle when the obstacle is detected; and an overlap ratio calculation means for calculating an overlap ratio of the obstacle in a vehicle width direction relative to the host vehicle when the obstacle is detected.a brake control means for determining a possibility of collision with the obstacle based on a relative distance and a relative speed between the host vehicle and the obstacle, and when it is determined that there is a high possibility of collision with the obstacle, executing a strong brake control to make the relative speed "0"; and a brake control means for performing a strong brake control until the relative speed with the obstacle becomes "0" by the strong brake control. The distance includes a certain margin. a steering intervention permission determination means for calculating a predicted travel distance and permitting steering intervention to avoid a collision with the obstacle when the predicted travel distance is longer than the relative distance; and a collision prediction time calculation means for calculating a predicted collision time until a collision with the obstacle when the strong brake control is activated. During execution of the strong brake control The steering intervention is permitted Then, a time threshold value that is a start time of the steering intervention is calculated from the relationship between the relative speed and the lap rate, The collision prediction time The above Time threshold is exceeded When it detects that and a steering control means for executing steering control for avoiding a collision with the obstacle. Effect of the Invention

[0011] According to the vehicle driving control device of the present invention, when emergency brake control is performed, emergency steering control can be intervened at an appropriate timing. [Brief description of the drawings]

[0012] [Figure 1] Overall configuration of the driving control system [Diagram 2] FIG. 1 is an explanatory diagram showing road-to-vehicle communication and vehicle-to-vehicle communication. [Diagram 3] FIG. 1 is an explanatory diagram showing a monitoring area of ​​a stereo camera and a radar device. [Figure 4] Flowchart showing emergency brake control routine [Diagram 5] Flowchart showing emergency steering control routine [Figure 6] FIG. 13 is an explanatory diagram showing an overlap ratio of an obstacle relative to the vehicle; [Figure 7] First map for setting the primary brake control start distance [Figure 8] Second map for setting the primary brake control start distance [Figure 9]Third map for setting the primary brake control start distance [Figure 10] The first map for setting the secondary brake control start distance [Figure 11] Second map for setting secondary brake control start distance [Figure 12] FIG. 11 is an explanatory diagram showing selection conditions of a map for setting a secondary brake control start distance. [Figure 13] FIG. 13 is an explanatory diagram showing a collision prediction time during secondary brake control. [Figure 14] Map for setting the time threshold for starting steering intervention [Figure 15] Flowchart showing a method for creating a map for setting the brake control start distance [Figure 16] Brake control start distance limit map [Figure 17] Schematic diagram of a map creation device for setting brake control start distance DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] Hereinafter, the embodiments of the present invention will be described with reference to the drawings. The drawings relate to one embodiment of the present invention, and FIG. 1 is an overall configuration diagram of a cruise control system. As shown in FIGS. 1 and 2, the cruise control system 1 in this embodiment is configured to include cruise control devices 10 mounted on a plurality of vehicles, and a plurality of control devices 100 provided in a network environment NW to which the plurality of cruise control devices 10 are connected via wireless communication. The control device 100 is provided as a server device in a network environment by cloud computing or edge computing, or a network environment by a roadside facility network, for example.

[0014] The control device 100 sequentially integrates and updates the road map information transmitted from the cruise control devices 10 of the vehicles, and transmits the updated road map information to the vehicles. For this reason, the control device 100 is configured to include a road map information integration_ECU 101 and a transceiver 102.

[0015] The road map boundary information integration_ECU 101 integrates road map information collected from multiple vehicles through the transceiver 102, and sequentially updates road map information surrounding a vehicle on a road. The road map information is, for example, a dynamic map, and has four layers of information: static information and quasi-static information that mainly constitute road information, and quasi-dynamic information and dynamic information that mainly constitute traffic information.

[0016] Static information is made up of information that needs to be updated within one month, such as roads, structures on roads, lane information, road surface information, and permanent traffic regulations.

[0017] Semi-static information is composed of information that needs to be updated within one hour, such as traffic regulation information due to road construction or events, wide-area weather information, and traffic congestion forecasts.

[0018] Semi-dynamic information consists of information that requires updates within one minute, such as actual traffic congestion conditions and driving restrictions at the time of observation, temporary driving impairments such as fallen objects and obstacles, actual accident conditions, and narrow-area weather information.

[0019] Dynamic information consists of information that must be updated within one second, such as information transmitted and exchanged between moving objects, information on currently displayed traffic signals, information on pedestrians and motorcycles within an intersection, and information on vehicles traveling straight through an intersection.

[0020] Such road map information is maintained and updated periodically until the next information is received from each vehicle, and the updated road map information is appropriately transmitted to each vehicle via the transceiver 102.

[0021] The driving control device 10 has a driving environment recognition unit 11 and a locator unit 12 as units for recognizing the driving environment outside the vehicle. The driving control device 10 also has a driving control unit (hereinafter referred to as "driving_ECU") 22, an engine control unit (hereinafter referred to as "E / G_ECU") 23, a power steering control unit (hereinafter referred to as "PS_ECU") 24, and a brake control unit (hereinafter referred to as "BK_ECU") 25. These control units 22 to 25 are connected to the driving environment recognition unit 11 and the locator unit 12 via an in-vehicle communication line such as a CAN (Controller Area Network).

[0022] The driving environment recognition unit 11 is fixed, for example, to the center of the upper part of the front part of the vehicle interior. The driving environment recognition unit 11 has an in-vehicle camera (stereo camera) consisting of a main camera 11a and a sub-camera 11b, an image processing unit (IPU) 11c, and a first driving environment recognition unit 11d.

[0023] The main camera 11a and the sub-camera 11b are, for example, autonomous sensors that sense the real space ahead of the vehicle M. The main camera 11a and the sub-camera 11b are, for example, arranged at symmetrical positions on either side of the center in the vehicle width direction, and capture stereo images of the area Af (see FIG. 3) ahead of the vehicle M from different viewpoints.

[0024] The IPU 11c processes the forward driving environment image information of the area in front of the vehicle M captured by both cameras 11a, 11b in a predetermined manner, and generates forward driving environment image information (distance image information) including distance information calculated from the amount of deviation between the positions of corresponding objects.

[0025] The first driving environment recognition unit 11d obtains lane markings that divide the roads around the host vehicle M based on distance image information received from the IPU 11c.

[0026] The first driving environment recognition unit 11d also obtains the road curvature [1 / m] of the dividing line dividing the left and right of the road (the vehicle's driving lane) on which the vehicle is driving, and the width between the left and right dividing lines (lane width). There are various known methods for obtaining the road curvature and lane width, but for example, the first driving environment recognition unit 11d recognizes the left and right dividing lines by binarization processing based on the brightness difference based on the forward driving environment image information, and obtains the curvature of the left and right dividing lines for each predetermined section by a curve approximation formula using the least squares method.

[0027] The first driving environment recognition unit 11d also performs predetermined pattern matching on the distance image information to recognize three-dimensional objects such as guardrails and curbs along the road, and pedestrians, motorcycles, and vehicles other than motorcycles that are on the road around the vehicle M. Here, when the first driving environment recognition unit 11d recognizes three-dimensional objects, it recognizes, for example, the type of the three-dimensional object, the distance to the three-dimensional object, the speed of the three-dimensional object, and the relative speed between the three-dimensional object and the vehicle M. Note that a three-dimensional object recognized based on an image from an on-board camera in this manner is referred to as a camera object (camera OBJ).

[0028] Furthermore, a plurality of radar devices (for example, a left front-side radar device 11fl, a right front-side radar device 11fr, a left rear-side radar device 11rl, and a right rear-side radar device 11rr) are connected to the first driving environment recognition unit 11d as autonomous sensors.

[0029] The left front side radar device 11fl and the right front side radar device 11fr are provided, for example, on the left and right sides of a front bumper, respectively. The left front side radar device 11fl and the right front side radar device 11fr monitor the areas Afl, Afr (see FIG. 3) diagonally forward and to the left and right of the vehicle M, which cannot be monitored by the images from the above-mentioned cameras 11a, 11b. The left front side radar device 11fl and the right front side radar device 11fr are disposed so that a part of each of the areas Afl, Afr overlaps with the area Af captured by the cameras 11a, 11b.

[0030] The left rear side radar device 11rl and the right rear side radar device 11rr are provided, for example, on the left and right sides of the rear bumper, respectively. The left rear side radar device 11rl and the right rear side radar device 11rr monitor areas Arl, Arr (see FIG. 3) from the left and right sides to the rear of the vehicle M, which cannot be monitored by the above-mentioned left front side radar device 11fl and right front side radar device 11fr. The left rear side radar device 11rl and the right rear side radar device 11rr are disposed such that the areas Arl, Arr partially overlap each other and overlap the areas Afl, Afr, respectively.

[0031] Each of the radar devices 11fl, 11fr, 11rl, and 11rr is configured to include a millimeter wave radar, a laser radar, a LIDAR (Light Detection and Ranging), and the like. Each of the radar devices 11fl, 11fr, 11rl, and 11rr emits radar waves (radio waves, laser beams, and the like) in the horizontal direction at each preset frame period, and receives the reflected waves of the emitted radar waves. As a result, each of the radar devices 11fl, 11fr, 11rl, and 11rr detects a plurality of reflection points on a three-dimensional object existing around the vehicle M. Then, each of the radar devices 11fl, 11fr, 11rl, and 11rr recognizes the three-dimensional object by analyzing the positions (relative positions with respect to the vehicle M) and the moving speeds of the detected plurality of reflection points and performing grouping processing. In addition, each of the radar devices 11fl, 11fr, 11rl, and 11rr sets the reflection point that is closest in linear distance to the vehicle M among the reflection points on the recognized three-dimensional object as the representative point of the three-dimensional object. Each of the radar devices 11fl, 11fr, 11rl, and 11rr recognizes, as information related to the representative point, for example, the position and relative speed Vr of the reflection point corresponding to the representative point, and recognizes the size of the three-dimensional object calculated from the distribution of the reflection points. Note that the three-dimensional object recognized in this manner by each of the radar devices 11fl, 11fr, 11rl, and 11rr is called a radar object (radar OBJ).

[0032] The information on the radar OBJ recognized in each of the radar devices 11fl, 11fr, 11rl, and 11rr in this manner is input to the first driving environment recognition unit 11d. As a result, the first driving environment recognition unit 11d is able to recognize various moving objects as three-dimensional objects, such as not only a preceding vehicle and the like in front of the vehicle M, but also a vehicle running parallel to the side of the vehicle M, a crossing vehicle approaching the vehicle M from a direction crossing the vehicle's travel path at an intersection, and a following vehicle behind the vehicle M.

[0033] Here, the first driving environment recognition unit 11d converts the positions of the recognized camera OBJ and radar OBJ into coordinates of an orthogonal coordinate system (a coordinate system in which the longitudinal direction of the vehicle M is the Z axis and the width direction of the vehicle M is the X axis: see FIG. 3) with the center of the vehicle M as the origin O. Furthermore, the first driving environment recognition unit 11d compares the camera OBJ with the radar OBJ, and recognizes a combination of the camera OBJ and the radar OBJ that matches based on a preset condition as a fusion object (fusion OBJ).

[0034] Locator unit 12 estimates the vehicle's position on a road map, and includes locator calculation unit 13 that estimates the vehicle's position. Sensors required for estimating the position of vehicle M (vehicle position) are connected to the input side of locator calculation unit 13, such as longitudinal acceleration sensor 14 that detects longitudinal acceleration of vehicle M, wheel speed sensor 15 that detects the rotational speed of each of the front, rear, left and right wheels, gyro sensor 16 that detects the angular velocity or angular acceleration of vehicle M, and GNSS receiver 17 that receives positioning signals transmitted from a plurality of positioning satellites. Also, transceiver 18 is connected to locator calculation unit 13 for transmitting and receiving information to and from control device 100 (road-to-vehicle communication: see dashed line in FIG. 2) and transmitting and receiving information to and from other vehicles (vehicle-to-vehicle communication: see dashed line in FIG. 2).

[0035] Further, the locator calculation unit 13 is connected to a high-precision road map database 19. The high-precision road map database 19 is a large-capacity storage medium such as an HDD, and stores high-precision road map information (dynamic map). This high-precision road map information has, for example, the same information as the road map information sequentially updated in the above-mentioned road map information integration_ECU 101, as information required for performing driving control of the host vehicle M. That is, the high-precision road map information has four layers of information consisting of static information and quasi-static information that mainly constitute road information, and quasi-dynamic information and dynamic information that mainly constitute traffic information.

[0036] Locator calculation unit 13 includes map information acquisition unit 13a, host vehicle position estimation unit 13b, and second driving environment recognition unit 13c.

[0037] The map information acquisition unit 13a acquires route map information from the current location to the destination from the map information stored in the high-precision road map database 19, based on the destination set by the driver during automatic driving, for example.

[0038] Furthermore, the map information acquisition unit 13a transmits the acquired route map information (lane data on the route map) to the vehicle position estimation unit 13b. The vehicle position estimation unit 13b acquires the position coordinates of the vehicle M based on the positioning signal received by the GNSS receiver 17. The vehicle position estimation unit 13b also performs map matching of the acquired position coordinates on the route map information to estimate the vehicle position on the road map, recognizes the left and right lane dividing lines that divide the vehicle's driving path (driving lane), and acquires the road curvature of the center of the driving lane stored in the road map data.

[0039] In addition, in an environment where a valid positioning signal from a positioning satellite cannot be received due to reduced sensitivity of the GNSS receiver 17, such as when driving inside a tunnel, the vehicle position estimation unit 13b switches to autonomous navigation, which estimates the vehicle position based on the vehicle speed calculated based on the wheel speed detected by the wheel speed sensor 15, the angular velocity detected by the gyro sensor 16, and the longitudinal acceleration detected by the longitudinal acceleration sensor 14, and estimates the vehicle position on a road map.

[0040] Furthermore, when the vehicle position estimation unit 13b estimates the vehicle position on a road map based on the positioning signal received by the GNSS receiver 17 or information detected by the gyro sensor 16, etc., as described above, it determines the road type, etc. of the road on which the vehicle M is traveling based on the estimated vehicle position on the road map.

[0041] The second driving environment recognition unit 13c updates the road map information stored in the high-precision road map database 19 to the latest state by using road map information acquired by external communication (road-to-vehicle communication and vehicle-to-vehicle communication) via the transceiver 18. This information update is performed not only for static information but also for quasi-static information, quasi-dynamic information, and dynamic information. As a result, the road map information is composed of road information and traffic information acquired by communication with the outside of the vehicle, and information on moving bodies such as vehicles traveling on roads is updated in approximately real time.

[0042] In addition, the second driving environment recognition unit 13c verifies the road map information based on the driving environment information recognized by the driving environment recognition unit 11, and updates the road map information stored in the high-precision road map database 19 to the latest state. This information update is performed not only on static information, but also on quasi-static information, quasi-dynamic information, and dynamic information. As a result, information on moving objects such as vehicles traveling on roads recognized by the driving environment recognition unit 11 is updated in real time.

[0043] The road map information thus updated is then transmitted to the control device 100 and surrounding vehicles of the host vehicle M by road-to-vehicle communication and vehicle-to-vehicle communication via the transceiver 18.

[0044] The second driving environment recognition unit 13c recognizes, from among the updated road map information, road map information within a set range centered on the vehicle position estimated by the vehicle position estimation unit 13b as the second driving environment information. Here, the range of the second driving environment information recognized by the second driving environment recognition unit 13c is wider than the first driving environment information recognized by the first driving environment recognition unit 11d, and for example, road map information within a 1 km radius centered on the vehicle position is recognized as the second driving environment information.

[0045] The first driving environment information recognized by the first driving environment recognition section 11d of the driving environment recognition unit 11 and the second driving environment information recognized by the second driving environment recognition section 13c of the locator unit 12 are read by the driving_ECU 22. Also, various switches and sensors are connected to the input side of the driving_ECU 22 (none of which are shown), such as a mode changeover switch for the driver to switch on / off the automatic driving (driving control), a steering torque sensor for detecting a steering torque as a driving operation amount by the driver, a brake sensor for detecting an amount of depression of a brake pedal as a driving operation amount by the driver, an accelerator sensor for detecting an amount of depression of an accelerator pedal as a driving operation amount by the driver, and a yaw rate sensor for detecting a yaw rate acting on the host vehicle M.

[0046] The driving modes set in the traveling_ECU 22 are a manual driving mode, a first driving control mode and a second driving control mode for driving control, and an evacuation mode. Each of these driving modes can be selectively switched in the traveling_ECU 22 based on the operation status of a mode change switch, etc.

[0047] Here, the manual driving mode is a driving mode that requires the driver to maintain steering, for example, a driving mode in which the host vehicle M is driven according to driving operations such as steering, accelerator, and brake operations by the driver.

[0048] Similarly, the first driving control mode is a driving mode that requires the driver to maintain steering. That is, the first driving control mode is a so-called semi-automatic driving mode in which the host vehicle M is driven along a target driving route by appropriately combining mainly a preceding vehicle following control (ACC: Adaptive Cruise Control), a lane centering control (ALKC: Active Lane Keep Centering) control, and a lane departure suppression control (Active Lane Keep Bouncing) control through control of the E / G_ECU 23, the PS_ECU 24, the BK_ECU 25, etc. while reflecting the driving operation by the driver.

[0049] The second driving control mode is an autonomous driving mode in which the host vehicle M is driven along a target route (route map information) by performing an appropriate combination of preceding vehicle following control, lane center keeping control, and lane departure prevention control, for example, through control of the E / G_ECU23, PS_ECU24, BK_ECU25, etc., without requiring the driver to maintain steering, operate the accelerator, or operate the brakes.

[0050] The evacuation mode is a mode for automatically stopping the vehicle M on a roadside or the like when, for example, while driving in the second driving control mode, driving in that mode cannot be continued and the driver is unable to take over driving operations (i.e., when it is not possible to transition to the manual driving mode or the first driving control mode).

[0051] Furthermore, in each of the above-mentioned driving modes, the travel_ECU 22 appropriately performs emergency braking (AEB (Autonomous Emergency Braking): collision damage mitigation brake) control for obstacles such as vehicles that are highly likely to collide with the host vehicle M. This emergency braking control is basically an interruption control that is performed based on the first traveling environment information.

[0052] This emergency brake control is basically performed based on the camera OBJ recognized by the stereo camera, and is performed in two stages, for example, a primary brake control and a secondary brake control.

[0053] The primary brake control is a warning brake control for prompting the driver to take action to avoid a collision with an obstacle, and is a gentle brake control for decelerating the host vehicle M using a relatively small deceleration a0.

[0054] The secondary brake control is a type of brake control that is performed when the driver does not perform appropriate collision avoidance operations in response to the primary brake control, and is a strong brake control that decelerates the vehicle M using a deceleration rate ap greater than that of the primary brake control until the relative speed between the vehicle and the obstacle becomes "0".

[0055] These brake controls are executed when the relationship between the relative speed Vrel and the relative distance dcam between the host vehicle M and the obstacle becomes equal to or smaller than a threshold value.

[0056] In this embodiment, specifically, the travel_ECU 22 calculates brake control start distances D1 and D2, which are distance thresholds, from the relationship between the relative speed Vrel between the host vehicle M and the obstacle and the overlap ratio R (see FIG. 6). In order to calculate these distance thresholds, a map for setting a primary brake control start distance and a map for setting a secondary brake control start distance are set in advance and stored in the travel_ECU 22 based on experiments, simulations, and the like. These maps are basically set so that the lower the relative speed Vrel, the smaller the distance threshold is set to delay the deceleration start timing, and the lower the overlap ratio R, the smaller the distance threshold is set to delay the deceleration start timing. That is, each map is set so that the lower the relative speed Vrel and the lower the overlap ratio R, the more room is left for the driver to avoid a collision with the obstacle by his / her own driving operation.

[0057] In addition, the collision prediction time TTC (Time To Collision) calculated by dividing the relative distance dcam by the relative speed Vrel is a parameter that is substantially synonymous with the relative distance dcam in brake control. Therefore, it is also possible to use the collision prediction time TTC as a parameter that indicates the relationship between the relative speed Vrel and the relative distance dcam, and set a map for calculating a time threshold value Tth for the collision prediction time TTC based on the relative speed Vrel and the relative distance dcam.

[0058] As maps for setting the primary brake control start distance, the traveling_ECU 22 stores first to third maps for calculating a different distance threshold (primary brake control start distance D1) depending on the traveling scene or the like.

[0059] The first map for setting the primary brake control initiation distance is a basic map for setting the intervention timing of the primary brake control (see FIG. 7).

[0060] The second map for setting the primary brake control initiation distance is, for example, a map set so that the timing of intervention of the primary brake control in the high speed range is delayed compared to the first map (see FIG. 8).

[0061] The third map for setting the primary brake control initiation distance is, for example, a map that is set so that the timing of intervention of the primary brake control in the high speed range is generally earlier than the second map (see FIG. 9).

[0062] As maps for setting the secondary brake control start distance, the traveling_ECU 22 stores first and second maps for calculating different threshold values ​​(secondary brake control start distance D2) depending on the driving scene and the like.

[0063] The first map for setting the secondary brake control start distance is a basic map for setting the timing of intervention of the secondary brake control (see FIG. 10). This first map for setting the secondary brake control start distance is basically selected in all driving scenes except for driving scenes in which the second map described later is selected (see FIG. 12).

[0064] The second map for setting the secondary brake control start distance is, for example, a map that is set so that the timing of intervention of the secondary brake control in a high speed range is earlier than that of the first map. The second map for setting the secondary brake control start distance is selected, for example, when the obstacle is a vehicle and the host vehicle M is traveling on a main lane of an expressway. More specifically, the second map for setting the secondary brake control start distance is selected when the obstacle is a vehicle, the host vehicle M is traveling on a main lane of an expressway, and the road shape of the host vehicle's traveling path recognized by the stereo camera is equal to or higher than a preset reliability for road map information (see FIG. 12).

[0065] The travel_ECU 22 selectively uses these maps to set a primary brake control start distance D1 and a secondary brake control start distance D2 with complementary calculation. Then, when the relative distance dcam becomes equal to or shorter than the primary brake control opening start distance D1, the travel_ECU 22 performs primary brake control at a preset deceleration a0. Furthermore, during the primary brake control, when the relative distance dcam becomes equal to or shorter than the secondary brake control start distance D2, the travel_ECU 22 performs secondary brake control at a preset deceleration ap.

[0066] Furthermore, when the traveling_ECU 22 determines that a collision with an obstacle cannot be avoided even if the secondary brake control is performed, the traveling_ECU 22 performs an emergency steering (AES (Autonomous Emergency Steering)) control to avoid a collision with the obstacle. Note that this emergency brake control is basically an interruption control performed based on the first traveling environment information, and in this embodiment, it is appropriately performed in parallel with the secondary brake control.

[0067] This emergency steering control is basically performed based on the camera OBJ recognized by the stereo camera.

[0068] In this emergency steering control, the traveling_ECU 22 calculates a travel distance (predicted travel distance Dp) from when the secondary brake control is started until the relative speed Vrel becomes "0". Then, when the predicted travel distance Dp is equal to or greater than the relative distance dcam, the traveling_ECU 22 determines that a collision with an obstacle cannot be avoided by the secondary brake control, and permits the intervention of the emergency steering control.

[0069] The calculation of the predicted travel distance Dp takes into consideration, for example, the travel distance during the control delay time of the cruise control device 10, the travel distance when the deceleration increases, the travel distance after the deceleration stabilizes, and a margin.

[0070] That is, for example, as shown in FIG. 13, in calculating the predicted travel distance Dp, the travel_ECU 22 calculates the distance that the host vehicle M will travel during a recognition delay time from when the traveling environment recognition unit 11 captures an image of an obstacle until the present time, and a control delay time such as a brake pressure increase delay time in the brake actuator 29 described later (control delay time travel distance d delay ) is calculated, for example, based on the following formula (1).

[0071] d delay =v0·(t rocn +t pres )+d v …(1) Here, in equation (1), t rocn is the recognition delay time, t pres is the brake fluid pressure rise delay time (see A and B in FIG. 13), both of which are constants specific to the host vehicle M. Also, v0 is the current relative speed Vrel. d v is the correction term for the relative speed change in the recognition delay time, and a p If the predicted stable deceleration (target deceleration for secondary brake control) is d v =(1 / 2)·a p t rcon 2 It is.

[0072] In addition, in calculating the predicted travel distance Dp, the travel_ECU 22 determines whether the deceleration is equal to or smaller than the target deceleration a p A travel distance d1 until the deceleration increases to 0 (when the deceleration increases) is calculated based on, for example, the following formula (2).

[0073] d1=(1 / 6)·j·t1 3 -(1 / 2)·a p t1 2 -v p t1…(2) In equation (2), j is the maximum deceleration jerk, a p is the target deceleration, a0 is the currently achieved speed a, t1 is the time it takes for the deceleration to increase (see C in FIG. 13), t1=(a p -a0) / j vp is the predicted relative velocity at the end of the deceleration increase, v p =(1 / 2) j t1 2 -a p t1+v0 It is.

[0074] In addition, in calculating the predicted travel distance Dp, the travel_ECU 22 calculates the travel distance d2+3 after the deceleration becomes stable based on the following formula (3).

[0075] d 2+3 =(1 / 2)·a p t 2+3 2 -v p t 2+3 …(3) Here, in equation (3), t 2+3 is the time it takes for the deceleration to stabilize until the relative speed becomes "0" (see D, E, and F in Figure 13), t 2+3 =v p / a p It is.

[0076] Then, the traveling_ECU 22 calculates a predicted traveling distance Dp until the relative speed Vrel becomes "0" as a result of the secondary brake control, based on, for example, the following equation (4).

[0077] Dp=d delay +d1+d 2+3 +d margin …(4) where d margin is a preset margin distance.

[0078] In addition, the traveling_ECU 22 calculates a collision prediction time TTC from the current time until the host vehicle M collides with an obstacle. Then, when the collision prediction time TTC becomes equal to or less than a time threshold Tth, the traveling_ECU 22 executes emergency steering control to avoid a collision with the obstacle.

[0079] Specifically, the travel_ECU 22 calculates, for example, a brake boost delay time t pres The collision prediction time TTC is calculated taking into account the travel time t1 of the deceleration increasing portion and the travel time t2 after the deceleration has stabilized.

[0080] That is, the traveling_ECU 22 calculates the traveling time from the current time until the target distance becomes 0 as the collision prediction time TTC, for example, using the following equation (5).

[0081] TTC=t pres +t1+t2…(5) Here, t2 is the travel time from when the deceleration stabilizes to when the margin is exceeded, t2=t 2+3 -t3 Furthermore, t3 is calculated as follows: t3=(2(Dp-dcam) / -a p ) 1 / 2 In addition, since the above-mentioned predicted travel distance Dp is used to calculate t3, the recognition delay time by the autonomous sensor is also taken into account in the calculation of the collision prediction time TTC.

[0082] In addition, the deceleration stable section running time t 2+3 In the calculation of the deceleration, when the deceleration is in the stable area, p and relative velocity v p The actual deceleration a and the current relative velocity Vrel are used.

[0083] In addition, the traveling_ECU 22 sets the time threshold value Tth with a supplementary calculation using, for example, a preset map (a map for setting the time threshold value for starting steering intervention).

[0084] This map for setting the time threshold for starting steering intervention is set based on experiments and simulations. For example, as shown in FIG. 14, the map is set so that the lower the relative speed Vrel, the smaller the time threshold is set to delay the steering start timing, and the lower the overlap rate R, the smaller the time threshold is set to delay the steering start timing.

[0085] When the collision prediction time TTC is equal to or shorter than the time threshold Tth, the travel_ECU 22 sets, for example, a position where the overlap rate R with the obstacle is "0" plus a predetermined margin as the target lateral position. The travel_ECU 22 generates a target trajectory using an estimated vehicle speed calculated from a model of the secondary brake control instead of the actual vehicle speed, and performs steering increase control and steering return control for the target lateral position. In this way, by using the estimated vehicle speed instead of the actual vehicle speed, the discrepancy between the target trajectory and the actual behavior during emergency steering control is eliminated.

[0086] In this manner, in the present embodiment, the traveling_ECU 22 Relative speed calculation means, overlap ratio calculation means, The device realizes the functions of a brake control means, a threshold setting means, a steering intervention permission determination means, a collision prediction time calculation means, and a steering control means.

[0087] A throttle actuator 35 is connected to the output side of the E / G_ECU 23. This throttle actuator 35 opens and closes a throttle valve of an electronically controlled throttle provided in a throttle body of the engine, and generates a desired engine output by opening and closing the throttle valve in response to a drive signal from the E / G_ECU 23 to adjust the intake air flow rate.

[0088] An electric power steering motor 36 is connected to the output side of the PS_ECU 24. This electric power steering motor 36 applies steering torque to the steering mechanism by the rotational force of the motor, and in autonomous driving, lane centering control for maintaining driving in the current driving lane and lane change control for moving the host vehicle M to an adjacent lane (lane change control for overtaking control, etc.) are performed by controlling the operation of the electric power steering motor 36 by a drive signal from the PS_ECU 24.

[0089] A brake actuator 37 is connected to the output side of the BK_ECU 25. This brake actuator 37 adjusts the brake hydraulic pressure supplied to the brake wheel cylinders provided on each wheel, and when the brake actuator 37 is driven by a drive signal from the BK_ECU 25, the brake wheel cylinders generate braking force on each wheel, forcibly decelerating the wheel.

[0090] Next, the emergency brake control executed in the travel_ECU 22 will be described with reference to a flowchart of an emergency brake control routine shown in Fig. 4. This routine is repeatedly executed at set time intervals.

[0091] When the routine starts, the driving_ECU 22 acquires information (subject vehicle information) regarding the host vehicle M in step S101, and then acquires the driving environment information (surrounding information) recognized by the first driving environment recognition unit 11d and the second driving environment recognition unit 13c in step S102.

[0092] In the following step S103, the travel_ECU 22 checks whether or not an obstacle is present ahead on the travel path of the host vehicle.

[0093] Then, in step S103, if it is determined that no obstacle is present ahead on the vehicle's travel path, the travel_ECU 22 exits the routine.

[0094] On the other hand, if it is determined in step S103 that an obstacle exists ahead on the travel path of the host vehicle, the travel_ECU 22 proceeds to step S104 and calculates the relative speed Vrel between the host vehicle M and the obstacle.

[0095] In the following step S105, the travel_ECU 22 calculates an overlap ratio R of the obstacle with respect to the host vehicle M (see FIG. 6).

[0096] In the following step S106, the traveling_ECU 22 selects a map for setting a primary brake control start distance and a map for setting a secondary brake control start distance from among a plurality of preset maps, based on preset conditions.

[0097] That is, the traveling_ECU 22 selects one of the first to third maps for setting the primary brake control start distance that are preset in advance, depending on the obstacle information (recognition information) obtained from the surrounding information, the vehicle information, etc.

[0098] The travel_ECU 22 also selects one of the first and second maps for setting the secondary brake control start distance according to the driving scene, etc. For example, as shown in FIG. 12, when at least one of the following conditions is not satisfied: the obstacle is a vehicle, the vehicle M is traveling on a main line of a highway, or the road shape, etc. of the vehicle's driving path recognized by the stereo camera is equal to or higher than a preset reliability level for road map information, the travel_ECU 22 selects the first map for setting the secondary brake control start distance. Also, when all of the following conditions are satisfied: the obstacle is a vehicle, the vehicle M is traveling on a main line of a highway, or the road shape, etc. of the vehicle's driving path recognized by the stereo camera is equal to or higher than a preset reliability level for road map information, the travel_ECU 22 selects the second map for setting the secondary brake control start distance.

[0099] Then, when proceeding to step S107, the travel_ECU 22 sets the primary brake control start distance D1 and the secondary brake control start distance D2 based on the map for setting the primary brake control start distance and the map for setting the secondary brake control start distance selected in step S106. That is, the travel_ECU 22 sets the primary brake control start distance D1 and the secondary brake control start distance D2 by referring to the map for setting the primary brake control start distance and the map for setting the secondary brake control start distance, using the relative speed Vrel between the host vehicle M and the obstacle and the overlap ratio R as parameters.

[0100] When proceeding from step S107 to step S108, the traveling_ECU 22 checks whether or not a cancellation condition for the emergency brake control is not satisfied. The cancellation condition includes, for example, a case where the first traveling environment recognition unit 11d is unable to recognize the traveling environment due to weather or the like, or various failures such as a failure of each ECU or the like.

[0101] Then, if it is determined in step S108 that the cancellation condition is satisfied, the traveling_ECU 22 exits the routine as is.

[0102] On the other hand, if it is determined in step S108 that the cancellation condition is not satisfied, the traveling_ECU 22 proceeds to step S109 and checks whether the relative speed Vrel is equal to or less than "0", i.e., whether the obstacle is moving at a speed moving away from the host vehicle M.

[0103] Then, in step S109, if it is determined that the relative speed Vrel is equal to or less than "0" and the obstacle is moving at a speed moving away from the host vehicle M, the travel_ECU 22 exits the routine.

[0104] On the other hand, if in step S109 it is determined that the relative speed Vrel is greater than "0" and the obstacle is moving at a speed approaching the host vehicle M, the travel_ECU 22 proceeds to step S110 and checks whether the distance (camera distance) dcam from the host vehicle M to the obstacle recognized by the stereo camera is less than or equal to the primary brake control start distance D1.

[0105] Then, in step S110, when it is determined that the camera distance dcam is greater than the primary brake control start distance D1, the traveling_ECU 22 exits the routine.

[0106] On the other hand, when it is determined in step S110 that the camera distance dcam is equal to or shorter than the primary brake control start distance D1, the traveling_ECU 22 proceeds to step S111 and checks whether or not the camera distance dcam is equal to or shorter than the secondary brake control start distance D2.

[0107] Then, in step S111, when it is determined that the camera distance dcam is greater than the secondary brake control start distance D2, the traveling_ECU 22 proceeds to step S112, executes the primary brake control, and then exits the routine.

[0108] On the other hand, if it is determined in step S112 that the camera distance dcam is equal to or shorter than the secondary brake control start distance D2, the traveling_ECU 22 proceeds to step S113, executes the secondary brake control, and then exits the routine.

[0109] Next, the emergency steering control executed in the travel_ECU 22 will be described with reference to a flowchart of an emergency steering control routine shown in Fig. 5. This routine is repeatedly executed at set time intervals.

[0110] When the routine starts, the driving_ECU 22 checks in step S201 whether or not the secondary brake control is currently being executed.

[0111] Then, when it is determined in step S201 that the secondary brake control is not being executed, the traveling_ECU 22 exits the routine.

[0112] On the other hand, if it is determined in step S201 that secondary braking is being performed, the traveling_ECU 22 proceeds to step S202 and calculates a predicted travel distance Dp until the relative speed between the vehicle M and the obstacle becomes "0" through secondary braking control.

[0113] In the following step S203, the traveling_ECU 222 checks whether the calculated predicted traveling distance Dp is equal to or greater than the camera distance dcam.

[0114] Then, in step S203, when it is determined that the predicted travel distance Dp is less than the camera distance dcam, the travel_ECU 22 exits the routine.

[0115] On the other hand, when it is determined in step S203 that the predicted travel distance Dp is equal to or less than the camera distance dcam, the travel_ECU 22 proceeds to step S204, permits steering intervention, and then proceeds to step S205.

[0116] In step S205, the traveling_ECU 22 calculates a collision prediction time TTC with an obstacle based on the current traveling state of the host vehicle M. In calculating the collision prediction time TTC, the traveling_ECU 22 uses, for example, a brake boost delay time t pres The collision prediction time TTC is calculated taking into account the travel time t1 of the deceleration increasing portion and the travel time t2 after the deceleration has stabilized.

[0117] In the next step S206, the travel_ECU 22 calculates a time threshold value Tth for the collision prediction time TTC based on a map for setting a time threshold value for starting steering intervention that is set in advance. That is, the travel_ECU 22 sets the time threshold value Tth by referring to the map for setting a time threshold value for starting steering intervention, using the relative speed Vrel between the host vehicle M and the obstacle and the overlap ratio R as parameters.

[0118] In the following step S207, the traveling_ECU 22 checks whether the calculated collision prediction time TTC is equal to or less than a time threshold value Tth.

[0119] Then, in step S207, if it is determined that the collision prediction time TTC is greater than the time threshold value Tth, the traveling_ECU 22 exits the routine.

[0120] On the other hand, if it is determined in step S207 that the collision prediction time TTC is equal to or less than the time threshold value Tth, the traveling_ECU 22 proceeds to step S208, and executes emergency steering control for the obstacle, and then exits the routine.

[0121] In the above example, the determination is made based on the camera distance dcam, but it is also possible to make the determination based on the relative distance between the host vehicle M and the obstacle calculated by a radar device.

[0122] Incidentally, the above-mentioned maps for setting the brake control initiation distances are generated, for example, by the following method.

[0123] This map generation method includes the steps of creating a map of brake control start distance for each generation condition based on experiments and simulations conducted under generation conditions such as preset driving conditions, verifying the generated map by comparing it with a limit value map of the brake control start distance, and correcting the brake control start distance of the generated map.

[0124] Here, the limit value of the brake control start distance is a limit value set in order to leave the avoidance of a collision with an obstacle in an emergency to the driver's proactive driving operation as much as possible. In other words, the limit value of the brake control start distance is an upper limit value for preventing excessive control intervention even at a timing when the collision with an obstacle can be avoided by the driver's driving operation.

[0125] Here, the limit value map of the brake control initiation distance is preset based on the normal steering avoidance limit distance ds and the normal braking avoidance limit distance db, for example, as shown below.

[0126] The normal steering avoidance limit distance ds is the distance required for the driver to perform a standard steering avoidance operation in relation to each relative speed Vrel between the vehicle M and the obstacle and each overlap rate R, and is set, for example, based on the following equation (6).

[0127] Ds=(0.0067·R+1.13)·Vrel…(6) The normal braking avoidance limit distance db is the distance required for the driver to perform a standard steering avoidance operation at each relative speed Vrel between the vehicle M and the obstacle, and is set, for example, regardless of the overlap ratio R based on the following equation (7).

[0128] Db=(0.00167·Vrel+1.00)·Vrel …(7) Then, a limit value map of the brake control start distance is generated by selecting the smaller of each set normal steering avoidance limit distance Ds and each set normal braking avoidance limit distance Db as the limit value of the brake control start distance in relation to the relative speed Vrel and the overlap ratio R (see FIG. 16). As a result, the limit value map of the brake control start distance is a map that also takes into consideration the avoidance of a collision with an obstacle by emergency steering control.

[0129] Next, a method for generating maps for setting each brake control start distance will be specifically described with reference to the flowchart showing the map generation procedure shown in Fig. 16. In this map generation method, for example, first to third maps are generated as maps for setting the primary brake control start distance, and first and second maps are generated as maps for setting the secondary brake control start distance.

[0130] In this map generating method, in step S301, a preset limit value map of the brake control initiation distance is obtained.

[0131] In the next step S302, a map for setting a primary brake control start distance is generated based on a preset generation condition. That is, for example, based on the result of an experiment or simulation performed under a selected generation condition using a vehicle carrying the maximum load of luggage, a map for setting a primary brake control start distance under the generation condition is generated.

[0132] In the following step S303, it is determined whether each value of the map for setting the primary brake control start distance generated in step S302 is within each corresponding value of the limit value map of the brake control start distance acquired in step S301.

[0133] Then, if it is determined in step S303 that at least one of the values ​​in the map for setting the primary brake control start distance is not within the corresponding value in the limit value map for the brake application start distance, the process proceeds to step S304, where the map for setting the primary brake control start distance is corrected, and then the process returns to step S303.

[0134] On the other hand, if it is determined in step S303 that each value of the map for setting the primary brake control start distance is within the corresponding value of the brake braking start distance limit value map, the process proceeds to step S305, where it is determined whether all patterns of maps (maps 1 to 3) have been generated as maps for setting the primary brake control start distance.

[0135] Then, in step S305, if it is determined that maps for all patterns have not been generated, the process returns to step S302, and a map for setting the primary brake control initiation distance is generated based on new generation conditions.

[0136] On the other hand, if it is determined in step S305 that maps for all patterns have been generated, the process proceeds to step S306, where a map for setting the secondary brake control start distance is generated based on a preset generation condition. That is, for example, based on the results of an experiment or simulation performed under a selected generation condition using a vehicle carrying the maximum load of luggage, a map for setting the secondary brake control start distance under the generation condition is generated.

[0137] In the following step S307, it is determined whether or not each value of the map for setting the secondary brake control start distance generated in step S305 is within each value of the limit value map of the braking start distance acquired in step S301.

[0138] If it is determined in step S307 that at least one of the values ​​in the map for setting the secondary brake control start distance is not within the corresponding value in the limit value map for the brake application start distance, the process proceeds to step S309.

[0139] On the other hand, if it is determined in step S307 that each value in the map for setting the secondary brake control start distance is within each value in the limit value map for the brake braking start distance, the process proceeds to step S308, where it is determined whether each value in the map for setting the secondary brake control start distance is less than the corresponding value in each map for setting the primary brake control start distance.

[0140] Then, in step S308, if it is determined that each value in the map for setting the secondary brake control start distance is less than the corresponding value in the map for setting each primary brake control start distance, the process proceeds to step S310, and if it is determined that at least one of the values ​​in the map for setting the secondary brake control start distance is not less than the corresponding value in the map for setting each primary brake control start distance, the process proceeds to step S309.

[0141] When the process proceeds from step S307 or step S308 to step S309, the map for setting the secondary brake control start distance is corrected, and then the process returns to step S307.

[0142] On the other hand, when the process proceeds from step S308 to step S310, it is determined whether or not all patterns of maps (first and second maps) have been generated as maps for setting the secondary brake control initiation distance.

[0143] Then, in step S310, if it is determined that maps for all patterns have not been generated, the process returns to step S306, and a map for setting the primary brake control initiation distance is generated based on new generation conditions.

[0144] On the other hand, if it is determined in step S310 that maps have been generated for all patterns, the map generation procedure is terminated.

[0145] It should be noted that such map generation can be performed by, for example, a map generation device 51 shown in Fig. 17, for all or part of each procedure. The map generation device 51 shown in Fig. 17 is configured, for example, by a computer device. This map generation device 51 is mainly configured with a computer main body 52 equipped with a central processing unit (hereinafter abbreviated as CPU) 52a and a storage device 52b that stores various data and programs, a keyboard 53 as a key input device, a mouse 54 as a pointing device, and a monitor 55 as a display device, all of which are connected to the computer main body 52.

[0146] According to this embodiment, the travel_ECU 22 is provided with a first map that sets the threshold based on the relative speed Vrel between the host vehicle M and an obstacle, and a second map that sets the threshold at high speeds of the relative speed Vrel to a value greater than that of the first map, as maps for setting the threshold for starting the secondary brake control, which is a strong brake control.By setting the threshold based on the second map when the host vehicle M is traveling on a highway and the obstacle is a vehicle, and setting the threshold based on the first map when at least one of the requirements that the host vehicle M is traveling on a highway or the obstacle is a vehicle is not met, it is possible to expand the cases in which a collision with an obstacle can be avoided even at high speeds while suppressing early intervention of emergency brake control.

[0147] That is, when at least one of the conditions that the host vehicle M is traveling on an expressway or the obstacle is a vehicle is not met, the secondary brake control is executed at a start timing based on the secondary brake control start distance set by the first map in which the intervention timing is suppressed, thereby suppressing early intervention of the secondary brake control. On the other hand, when the host vehicle M is traveling on an expressway and the obstacle is a vehicle, the secondary brake control is executed at a start timing based on the secondary brake control start distance set by the second map in which the intervention timing in the high speed range is made earlier than that in the first map, thereby expanding the cases in which a collision with an obstacle can be avoided even in the high speed range.

[0148] In addition, in the primary brake control, by using different maps (first to third maps) according to the driving scene, etc., it is possible to suppress early intervention of the primary brake control and execute the primary brake control at an appropriate timing.

[0149] In this case, each map sets the threshold value to a smaller value as the overlap ratio R of the obstacle relative to the vehicle M decreases, thereby delaying the timing of control intervention, thereby enabling emergency brake control to be performed at an appropriate timing that also takes into account the avoidance of a collision with the obstacle through steering.

[0150] In addition, each map sets a threshold value that is lower than the limit value of a preset brake control start distance limit value map based on the standard steering timing for the driver to avoid a collision with an obstacle by steering and the standard braking timing for the driver to avoid a collision with an obstacle by braking, so that emergency brake control can be executed at the appropriate timing while leaving room for the driver to perform obstacle avoidance operations.

[0151] Furthermore, according to this embodiment, the travel_ECU 22 calculates a predicted travel distance Dp until the relative speed with respect to the obstacle becomes "0" due to the secondary brake control, which is a strong brake control, while the secondary brake control is being executed, and allows steering intervention to avoid various collisions with the obstacle when the predicted travel distance Dp is longer than the relative distance dcam with the obstacle, and calculates a predicted collision time TTC until a collision with the obstacle occurs when the secondary brake control is activated, and executes emergency steering control to avoid a collision with the obstacle when steering intervention is permitted and the predicted collision time becomes equal to or less than the time threshold value Tth, thereby allowing emergency steering control to intervene at an appropriate timing when the secondary brake control is executed.

[0152] In other words, instead of immediately executing emergency steering control when it is determined that the predicted traveling distance Dp immediately after the secondary brake control is activated is longer than the relative distance dcam from the obstacle, emergency steering control is executed when a separately calculated collision prediction time TTC falls below a time threshold value, thereby making it possible to suppress early intervention of emergency steering control, and even when emergency brake control is executed, emergency steering control can be executed at an appropriate timing while leaving room for the driver to steer away from the obstacle, etc.

[0153] In this case, the predicted travel distance Dp is calculated by taking into account the recognition delay time by the autonomous sensor, the brake pressure increase delay time in the secondary brake control, and the distance traveled by the vehicle M during the increase time of deceleration to the target deceleration in the secondary emergency brake control, thereby making it possible to make a more precise decision on whether to allow steering intervention.

[0154] In addition, the calculation of the collision prediction time TTC takes into account the recognition delay time by the autonomous sensor, the brake pressure increase delay time in the secondary brake control, and the increase time of the deceleration to the target deceleration in the secondary emergency brake control, thereby enabling the intervention of emergency steering control with more precise timing.

[0155] In the above embodiment, the driving environment recognition unit 11, the locator unit 12, the driving_ECU 22, the E / G_ECU 23, the PS_ECU 24, the BK_ECU 25, the road map information integration_ECU 101, and the computer main body 52 are configured with a well-known microcomputer equipped with a CPU, RAM, ROM, a non-volatile storage unit, etc., and its peripheral devices, and the ROM stores programs to be executed by the CPU and fixed data such as data tables in advance. Note that all or part of the functions of the processor may be configured with a logic circuit or an analog circuit, and the processing of various programs may be realized by an electronic circuit such as an FPGA.

[0156] The invention described in the above embodiments is not limited to those embodiments, and various modifications can be made in the implementation stage without departing from the gist of the invention. Furthermore, the above embodiments include inventions at various stages, and various inventions can be extracted by appropriate combinations of the disclosed constituent elements.

[0157] For example, if some of the constituent elements shown in the embodiment can be deleted and the problem described can be solved and the effect described can be obtained, the configuration from which the constituent elements have been deleted can be extracted as an invention. [Explanation of symbols]

[0158] 1 … Driving control system 10 ... Driving control device 11 … Driving environment recognition unit 11a ... Main camera 11b … Sub camera 11c … IPU 11d … First driving environment recognition section 11fl … Left front side radar device 11fr … Right front side radar device 11rl ... Left rear side radar device 11rr … Right rear side radar device 12 … Locator unit 13 ... Locator calculation section 13a … Map information acquisition section 13b ... Vehicle position estimation unit 13c … Second driving environment recognition section 14 ... Front and rear acceleration sensor 15 ... Wheel speed sensor 16 ... Gyro sensor 17 … GNSS receiver 18 … Transmitter / Receiver 19 … High-precision road map database 22 … Driving_ECU 23 … E / G_ECU 24 … PS_ECU 25 … BK_ECU 35 ... Throttle actuator 36 ... Electric power steering motor 37 ... Brake actuator 100 … control device 101 ... Road map information integration_ECU 102 ... Transmitter / Receiver

Claims

1. An autonomous sensor that recognizes obstacles ahead of the vehicle; a relative speed calculation means for calculating a relative speed between the host vehicle and the obstacle when the obstacle is detected; an overlap ratio calculation means for calculating an overlap ratio of the obstacle in a vehicle width direction relative to the host vehicle when the obstacle is detected; a brake control means for determining a possibility of collision with the obstacle based on a relative distance and a relative speed between the host vehicle and the obstacle, and for executing a strong brake control to make the relative speed "0" when it is determined that there is a high possibility of collision with the obstacle; a steering intervention permission determination means for calculating a predicted travel distance including a predetermined margin from a distance until the relative speed with respect to the obstacle becomes "0" by the hard brake control, and permitting steering intervention to avoid a collision with the obstacle when the predicted travel distance is longer than the relative distance; a collision prediction time calculation means for calculating a collision prediction time until a collision with the obstacle occurs when the strong brake control is activated; a steering control means for calculating a time threshold value that is a start time of the steering intervention from the relationship between the relative speed and the lap rate when the steering intervention is permitted during execution of the hard brake control, and for executing a steering control for avoiding a collision with the obstacle when it is detected that the collision prediction time is equal to or shorter than the time threshold value; A vehicle driving control device comprising:

2. 2. The vehicle driving control device according to claim 1, wherein the collision prediction time calculation means calculates the collision prediction time by taking into account a recognition delay time by the autonomous sensor, a brake pressure increase delay time in the hard braking control, and a time required for the deceleration to increase to a target deceleration in the hard braking control.

3. 3. The vehicle driving control device according to claim 1, wherein the steering intervention permission determination means calculates the predicted travel distance by taking into account the recognition delay time by the autonomous sensor, the brake pressure increase delay time in the hard braking control, and the distance traveled by the vehicle during the time it takes for the deceleration to increase to the target deceleration in the hard braking control.

4. 4. The vehicle travel control device according to claim 1, wherein the brake control means delays the activation timing of the strong brake control as the overlap ratio of the obstacle to the vehicle width direction of the host vehicle decreases.

5. The steering control means The time threshold is set to be smaller as the relative speed decreases and as the lap ratio decreases, thereby leaving a margin for the driver of the host vehicle to avoid a collision with the obstacle by a driving operation.

2. The vehicle travel control device according to claim 1.

6. The steering control means When the steering intervention is permitted during the execution of the strong brake control, the time threshold value that is an upper limit value for waiting for a steering operation by the driver of the host vehicle to avoid a collision with the obstacle is calculated from the relationship between the relative speed and the lap ratio; When it is detected that the collision prediction time is equal to or less than the time threshold, an operation control for avoiding the collision with the obstacle is executed.

2. The vehicle travel control device according to claim 1.

7. The steering control means A preset value is used as the time threshold value so as to be smaller as the relative speed decreases and as the overlap ratio decreases, When a steering operation for avoiding a collision with the obstacle by the driver of the host vehicle is detected before the time threshold is reached, the steering operation is prioritized and the steering control is interrupted.

2. The vehicle travel control device according to claim 1.

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