Vehicle driving assistance device

Abstract

To provide an operation support device for a vehicle which can avoid interference with peripheral vehicles in a new traffic lane after changing lane.SOLUTION: A traveling_ECU14 keeps, when an own vehicle M starts changing lane to a traveling lane during traveling with following travel control, target vehicle speed Vt at the time of starting changing lane at least until completing changing lane, and then sets a specified vehicle speed Vs as new target vehicle speed Vt and sets target acceleration at based on the new target vehicle speed Vt to accelerate the own vehicle M.SELECTED DRAWING: Figure 5

Description

[Technical Field]

[0001] The present invention relates to a driving assistance device for a vehicle equipped with an adaptive vehicle-following distance control function. [Background technology]

[0002] BACKGROUND ART In recent years, driving assistance devices for assisting drivers in driving operations have been put into practical use in vehicles such as automobiles, with the aim of reducing the burden of driving operations on drivers and improving safety.

[0003] Such driving assistance devices are configured with various modes, such as a manual driving mode in which steering and acceleration / deceleration are performed according to the driver's proactive driving operations, a driving assistance mode in which steering assistance control and acceleration / deceleration control are performed based on the driver's proactive driving operations, and a driving assistance mode (so-called automatic driving mode) in which the vehicle is driven without the need for driver operation.

[0004] Specifically, the driving assistance control in each driving assistance mode is realized by providing an adaptive cruise control (ACC) function, an active lane keep centering (ALKC) function, etc. Such driving assistance control enables the vehicle to automatically travel along the lane while maintaining a safe distance from the vehicle ahead.

[0005] In adaptive cruise control (cruise control), for example, when a preceding vehicle is detected ahead in the lane in which the host vehicle is traveling, adaptive cruise control is performed to follow the preceding vehicle. In adaptive cruise control, a target acceleration is calculated based on the relative speed and inter-vehicle distance between the host vehicle and the preceding vehicle, and the adaptive cruise control is performed to reduce the deviation between a preset target inter-vehicle distance and the current inter-vehicle distance to zero. Then, acceleration / deceleration control is performed according to the target acceleration, so that the adaptive cruise control can make the host vehicle follow the preceding vehicle while maintaining the target inter-vehicle distance.

[0006] On the other hand, in the adaptive cruise control, when no preceding vehicle is detected ahead in the lane in which the host vehicle is traveling, constant speed cruise control is performed. In the constant speed cruise control, a target acceleration is calculated to make the speed difference between the host vehicle's current speed and a set speed zero. Then, acceleration / deceleration control is performed according to the target acceleration, so that the host vehicle can travel at the set speed.

[0007] Such adaptive vehicle distance control can also be applied when the host vehicle changes lanes. When the host vehicle is following a preceding vehicle, the vehicle speed is generally lower than a set vehicle speed. Furthermore, a lane change is generally performed on the assumption that there is no preceding vehicle within a set distance of the adjacent lane into which the host vehicle will change lanes. Therefore, when the host vehicle changes lanes while following a preceding vehicle, the vehicle speed of the host vehicle is generally accelerated to the set vehicle speed by adaptive vehicle distance control as the host vehicle changes lanes. [Prior art documents] [Patent documents]

[0008] [Patent Document 1] Japanese Patent Application Laid-Open No. 2007-186097 Summary of the Invention [Problem to be solved by the invention]

[0009] However, when the host vehicle changes lanes to an adjacent lane, the relative relationship between the host vehicle and surrounding vehicles changes in various ways. Therefore, if acceleration accompanying a lane change is uniformly performed by adaptive inter-vehicle distance control, the host vehicle speed may not be appropriate for avoiding interference with surrounding vehicles. In such a case, further acceleration or deceleration may be required to avoid interference with surrounding vehicles.

[0010] The present invention has been made in consideration of the above circumstances, and aims to provide a vehicle driving assistance device that can appropriately avoid interference with surrounding vehicles in a new lane after a lane change. [Means for solving the problem]

[0011] A driving assistance device for a vehicle according to one aspect of the present invention includes a driving environment recognition unit that recognizes driving environment information outside the vehicle, and a driving environment recognition unit that, when a preceding vehicle is recognized ahead of the host vehicle based on the driving environment information, calculates a vehicle speed of the preceding vehicle. is lower than the set vehicle speed input by the driver, and performing a follow-up running control to cause the host vehicle to follow the preceding vehicle at a target vehicle speed that is set in accordance with the target vehicle speed, and when a preceding vehicle is not recognized ahead of the host vehicle, The aforementioned and a following vehicle distance control means for performing constant speed traveling control to cause the host vehicle to travel at a constant speed by setting a set vehicle speed to the target vehicle speed, wherein when the host vehicle starts to change lanes into a traveling lane while traveling under the following traveling control, the following vehicle distance control means set according to the speed of the preceding vehicle After maintaining the target vehicle speed at least until the lane change is completed After the set time has elapsed, to , the target vehicle speed The set vehicle speed in new Tani Along with setting Set New target vehicle speed and the speed difference between the vehicle speed of the host vehicle Based on tree A target acceleration is set and the host vehicle is accelerated. [Effects of the Invention]

[0012] According to the vehicle driving assistance device of the present invention, it is possible to appropriately avoid interference with surrounding vehicles in the new lane after a lane change. [Brief explanation of the drawings]

[0013] [Figure 1] Overall configuration of the driving assistance device [Figure 2] FIG. 1 is an explanatory diagram showing the monitoring areas of a stereo camera and a radar; [Figure 3] Flowchart showing lane change control routine [Figure 4] Flowchart showing a vehicle speed control routine with lane changes during adaptive cruise control (part 1) [Figure 5]Flowchart showing a vehicle speed control routine with lane changes during adaptive cruise control (part 2) [Figure 6] Flowchart showing a vehicle speed control routine with lane changes during adaptive cruise control (part 3) [Figure 7] A time chart illustrating steering angle and vehicle speed characteristics when changing lanes to a driving lane [Figure 8] A time chart illustrating steering angle and vehicle speed characteristics when changing lanes to an overtaking lane [Figure 9] FIG. 10 is an explanatory diagram showing a vehicle following a preceding vehicle in an overtaking lane. [Figure 10] An explanatory diagram showing a vehicle changing lanes into a driving lane [Figure 11] An explanatory diagram showing the vehicle after changing lanes into the driving lane [Figure 12] FIG. 1 is an explanatory diagram showing a vehicle following a preceding vehicle in a driving lane; [Figure 13] An explanatory diagram showing the vehicle changing lanes into the passing lane [Figure 14] An explanatory diagram showing the vehicle after changing lanes into the passing lane DETAILED DESCRIPTION OF THE INVENTION

[0014] An embodiment of one aspect of the present invention will be described in detail below with reference to the drawings. Note that in the drawings used in the following description, each component is shown at a different scale so that it can be recognized. Therefore, the present invention is not limited to the number of components, the shapes of the components, the size ratios of the components, and the relative positional relationships of the components shown in these drawings.

[0015] As shown in FIGS. 1 and 2, the driving assistance device 1 includes a camera unit 10 fixed to the center of the upper front part of the interior of a vehicle (host vehicle) M, for example.

[0016] The camera unit 10 includes a stereo camera 11, an image processing unit (IPU) 12, an image recognition unit (image recognition_ECU) 13, and a driving control unit (driving_ECU) 14.

[0017] The stereo camera 11 has a main camera 11a and a sub-camera 11b. The main camera 11a and the sub-camera 11b are configured with, for example, a CMOS, and are arranged at symmetrical positions across the center of the vehicle in the width direction. The main camera 11a and the sub-camera 11b capture stereo images of the driving environment in an area Af (see FIG. 2) outside the vehicle from different viewpoints at a predetermined imaging cycle that is synchronized with each other.

[0018] The IPU 12 processes the driving environment images captured by the stereo camera 11 in a predetermined manner to detect the edges of various objects, such as three-dimensional objects and road markings, displayed in the images. The IPU 12 then calculates distance information from the positional deviation of corresponding edges in the left and right images. As a result, the IPU 12 generates image information (distance image information) that includes distance information.

[0019] Based on distance image information received from the IPU 12, the image recognition_ECU 13 calculates the road curvature [1 / m] of the marking lines that divide the left and right lanes (the lane on which the vehicle M is traveling) and the width between the left and right marking lines (lane width). The image recognition_ECU 13 also calculates the road curvature and the width between the left and right marking lines of lanes adjacent to the lane on which the vehicle M is traveling. Various methods are known for calculating the road curvature and lane width. For example, the image recognition_ECU 13 recognizes the left and right marking lines by binarizing the road curvature based on the driving environment information using brightness differences, and calculates the curvature of the left and right marking lines for each predetermined section using a curve approximation formula based on the least squares method. Furthermore, the image recognition_ECU 13 calculates the lane width from the difference in curvature between the left and right marking lines.

[0020] Then, the image recognition_ECU 13 calculates the lane center and the lateral position deviation of the host vehicle M based on the curvature of the left and right lane markings and the lane width. Here, the lateral position deviation of the host vehicle M is the distance from the lane center to the center of the host vehicle M in the vehicle width direction.

[0021] Furthermore, the image recognition_ECU 13 performs predetermined pattern matching on the distance image information, thereby recognizing three-dimensional objects such as guardrails, curbs, and surrounding vehicles that extend along the road. Here, the recognition of three-dimensional objects by the image recognition_ECU 13 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 host vehicle M.

[0022] The various pieces of information recognized by the image recognition_ECU 13 are output to the traveling_ECU (traveling_ECU) 14 as traveling environment information.

[0023] In this manner, in this embodiment, the image recognition_ECU 13, together with the stereo camera 11 and the IPU 12, corresponds to a specific example of a driving environment recognition means that recognizes driving environment information outside the vehicle.

[0024] The traveling_ECU 14 is a control unit for controlling the driving assistance device 1 in an integrated manner.

[0025] This traveling_ECU 14 is connected to various control units, such as a cockpit control unit (CP_ECU) 21, an engine control unit (E / G_ECU) 22, a transmission control unit (T / M_ECU) 23, a brake control unit (BK_ECU) 24, and a power steering control unit (PS_ECU) 25, via an in-vehicle communication line such as a CAN (Controller Area Network).

[0026] Furthermore, the travel_ECU 14 includes various sensors, such as a locator unit 36, a left front side sensor 37lf, a right front side sensor 37rf, and a left rear side sensor 37l. rand the right rear side sensor 37rr are connected.

[0027] A human-machine interface (HMI) 31 disposed near the driver's seat is connected to the CP_ECU 21. The HMI 31 includes, for example, an operation switch for executing and setting various driving assistance controls, a mode selector switch for switching driving assistance modes, a steering touch sensor for detecting the driver's steering state, a turn signal switch, a driver monitoring system (DMS) for detecting the driver's face recognition and line of sight, a touch panel display, a combination meter, a speaker, and the like.

[0028] When the CP_ECU 21 receives a control signal from the driving_ECU 14, it appropriately notifies the driver of various information regarding various warnings for preceding vehicles, the implementation status of driving assistance control, and the driving environment of the vehicle M, by displaying or audibly displaying via the HMI 31.

[0029] In addition, the CP_ECU 21 outputs various input information to the driving_ECU 14, such as the on / off operation status of various driving assistance controls input by the driver through the HMI 31, the set vehicle speed (set vehicle speed) Vs for the vehicle M, and the operation status of the turn signal switch.

[0030] The output side of the E / G_ECU 22 is connected to a throttle actuator 32 of an electronically controlled throttle, etc. The input side of the E / G_ECU 22 is connected to various sensors such as an accelerator sensor (not shown).

[0031] The E / G_ECU 22 controls the operation of the throttle actuator 32 based on a control signal from the travel_ECU 14 or detection signals from various sensors. In this way, the E / G_ECU 22 adjusts the amount of intake air into the engine to generate a desired engine output. The E / G_ECU 22 also outputs signals such as the accelerator opening detected by the various sensors to the travel_ECU 14.

[0032] An output side of the T / M_ECU 23 is connected to a hydraulic control circuit 33. Furthermore, various sensors such as a shift position sensor (not shown) are connected to an input side of the T / M_ECU 23. The T / M_ECU 23 performs hydraulic control for the hydraulic control circuit 33 based on an engine torque signal estimated by the E / G_ECU 22 and detection signals from various sensors. As a result, the T / M_ECU 23 operates friction engagement elements, pulleys, and the like provided in the automatic transmission, and shifts the engine output at a desired gear ratio. Furthermore, the T / M_ECU 23 outputs signals such as the shift position detected by the various sensors to the travel_ECU 14.

[0033] A brake actuator 34 is connected to the output side of the BK_ECU 24. The brake actuator 34 adjusts the brake fluid pressure output to the brake wheel cylinders provided on each wheel. In addition, various sensors such as a brake pedal sensor, a yaw rate sensor, a longitudinal acceleration sensor, and a vehicle speed sensor (not shown) are connected to the input side of the BK_ECU 24.

[0034] The BK_ECU 24 performs drive control on the brake actuator 34 based on control signals from the travel_ECU 14 or detection signals from various sensors. As a result, the BK_ECU 24 appropriately generates braking force on each wheel to perform forced braking control, yaw rate control, etc. on the host vehicle M. In addition, the BK_ECU 24 outputs signals of the brake operation state, yaw rate, longitudinal acceleration, vehicle speed (host vehicle speed), etc. detected by the various sensors to the travel_ECU 14.

[0035] An electric power steering motor 35 is connected to the output side of the PS_ECU 25. The electric power steering motor 35 applies steering torque to the steering mechanism by the rotational force of the motor. In addition, various sensors such as a steering torque sensor and a steering angle sensor are connected to the input side of the PS_ECU 25.

[0036] The PS_ECU 25 controls the drive of the electric power steering motor 35 based on control signals from the travel_ECU 14 or detection signals from various sensors. As a result, the PS_ECU 25 generates a steering torque for the steering mechanism. The PS_ECU 25 also outputs signals of the steering torque, steering angle, etc. detected by the various sensors to the travel_ECU 14.

[0037] The locator unit 36 ​​includes a GNSS sensor 36a and a high-precision road map database (road map DB) 36b.

[0038] The GNSS sensor 36a receives positioning signals transmitted from a plurality of positioning satellites to determine the position (latitude, longitude, altitude, etc.) of the vehicle M.

[0039] The road map DB 36b is a large-capacity storage medium such as an HDD. High-precision road map information (dynamic map) is stored in this road map DB 36b. The road map information includes, for example, lane data required for autonomous driving, such as lane width data, lane center position coordinate data, lane travel azimuth data, and speed limit data. The lane data is stored at intervals of several meters for each lane on the road map. For example, based on a request signal from the traveling_ECU 14, the road map DB 36b outputs road map information of a set range based on the vehicle position measured by the GNSS sensor 36a to the traveling_ECU 14 as traveling environment information.

[0040] Thus, in this embodiment, the road map DB 36b, together with the GNSS sensor 36a, corresponds to a specific example of a driving environment recognition means that recognizes driving environment information outside the vehicle.

[0041] The left front side sensor 37lf and the right front side sensor 37rf are configured by, for example, millimeter-wave radars. These left front side sensor 37lf and right front side sensor 37rf are disposed, for example, on the left and right sides of the front bumper, respectively. The left front side sensor 37lf and the right front side sensor 37rf detect, as driving environment information, three-dimensional objects present in areas Alf, Arf (see FIG. 2) diagonally forward and to the left and right of the vehicle M, which are difficult to recognize in the image from the stereo camera 11.

[0042] The left rear side sensor 37lr and the right rear side sensor 37rr are configured by, for example, millimeter wave radars. The left rear side sensor 37lr and the right rear side sensor 37rr are disposed, for example, on the left and right sides of the rear bumper, respectively. r The right rear side sensor 37rf detects, as driving environment information, three-dimensional objects present in the areas Alr, Arr (see Figure 2) diagonally to the left and right and behind the vehicle M, which are difficult to recognize with the left front side sensor 37lf and the right front side sensor 37rf.

[0043] Here, when each radar is configured as a millimeter wave radar, the millimeter wave radar mainly detects three-dimensional objects such as adjacent vehicles and following vehicles by analyzing the waves reflected from the objects in response to the output radio waves. Specifically, each radar detects information about the three-dimensional object, such as the width of the three-dimensional object, the position of a representative point of the three-dimensional object (the relative position with respect to the vehicle M), and the speed.

[0044] Thus, in this embodiment, the left front side sensor 37lf, the right front side sensor 37rf, the left rear side sensor 37lr, and the right rear side sensor 37rr correspond to a specific example of a driving environment recognition means that recognizes driving environment information outside the vehicle.

[0045] The driving environment information recognized by the image recognition ECU 13, the driving environment information recognized by the locator unit 36, the driving environment information recognized by the left front side sensor 37lf, the driving environment information recognized by the right front side sensor 37rf, the driving environment information recognized by the left rear side sensor 37l rThe coordinates of each object outside the vehicle included in the driving environment information recognized by the right rear side sensor 37rr and the driving environment information recognized by the right rear side sensor 37rr are converted in the driving_ECU 14 into coordinates of a three-dimensional coordinate system (see Figure 2) with the center of the vehicle M as the origin, for example.

[0046] The driving modes set in the travel_ECU 14 include a manual driving mode, a first driving control mode and a second driving control mode for driving control, and an evacuation mode. These driving modes can be selectively switched in the travel_ECU 14 based on, for example, the operation status of a mode selector switch provided in the HMI 31.

[0047] Here, the manual driving mode is a driving mode that requires the driver to maintain steering, i.e., the manual driving mode is 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] The first driving control mode is also 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 while reflecting the driving operation by the driver. This first driving control mode is realized, for example, by the driving_ECU 14 outputting various control signals to the E / G_ECU 22, the BK_ECU 24, and the PS_ECU 25. In the first driving control mode, mainly, adaptive cruise control (ACC), active lane keep centering (ALKC), active lane keep bouncing (ALKC), lane change control, etc. are appropriately combined. This enables the host vehicle M to travel along a target driving route. Furthermore, in the first driving control mode, lane change control can also be performed when the driver operates a turn signal switch.

[0049] Here, the following inter-vehicle distance control is basically performed based on the traveling environment information input from the image recognition_ECU 13 and the like.

[0050] Specifically, when a preceding vehicle is recognized in front of the host vehicle M by the image recognition_ECU 13 or the like, the traveling_ECU 14 performs follow-up traveling control as part of the follow-up inter-vehicle distance control. In this follow-up traveling control, the traveling_ECU 14 detects the vehicle speed of the preceding vehicle, Vf The target inter-vehicle distance Lt and the target vehicle speed Vt are set based on the above. Then, the travel_ECU 14 performs acceleration / deceleration control on the host vehicle M based on the target inter-vehicle distance Lt and the target vehicle speed Vt. As a result, the travel_ECU 14 basically maintains the inter-vehicle distance L at the target inter-vehicle distance Lt, Vehicle M's The host vehicle M is caused to travel following the preceding vehicle while maintaining the vehicle speed V at the target vehicle speed Vt.

[0051] On the other hand, when, for example, the image recognition_ECU 14 or the like does not recognize a preceding vehicle ahead of the host vehicle M, the travel_ECU 14 performs constant speed traveling control as part of the follow-up inter-vehicle distance control. In this constant speed traveling control, the travel_ECU 14 sets the set vehicle speed Vs input by the driver as the target vehicle speed Vt. Then, the travel_ECU 14 performs acceleration / deceleration control on the host vehicle M based on the target vehicle speed Vt. In this way, the travel_ECU 14 maintains the vehicle speed V of the host vehicle M at the set vehicle speed Vs.

[0052] Furthermore, the lane centering control and lane departure prevention control are basically performed based on the driving environment information input from at least one of the image recognition_ECU 13 and the locator unit 36. That is, the driving_ECU 14 performs the lane centering control and the lane departure prevention control for the lane in which the host vehicle M is traveling, based on, for example, lane marking information included in the driving environment information. In this way, the driving_ECU 14 keeps the host vehicle M in the center of the lane.

[0053] The lane change control is basically performed based on driving environment information input from the image recognition_ECU 13, the left front side sensor 37lf, the right front side sensor 37rf, the left rear side sensor 37lr, and the right rear side sensor 37rr. This lane change control is executed, for example, when the driver operates the turn signal switch. That is, the driving_ECU 14 recognizes an adjacent lane that exists in the direction of operation of the turn signal switch based on the driving environment information. The driving_ECU 14 also recognizes whether or not there is a vehicle or the like on the adjacent lane that may obstruct the lane change. Then, when the driving_ECU 14 determines that there is space on the adjacent lane where a lane change is possible, it performs a lane change to the adjacent lane. This lane change control is performed in coordination with the following vehicle distance control.

[0054] The second driving control mode is a driving mode in which the host vehicle M is driven without the driver needing to maintain steering, operate the accelerator, or operate the brakes. In other words, the second driving control mode is a so-called automatic driving mode in which the host vehicle M is driven autonomously without the driver needing to perform any driving operation. This second driving control mode is realized, for example, by the driving_ECU 14 outputting various control signals to the E / G_ECU 22, the BK_ECU 24, and the PS_ECU 25. In the second driving control mode, a preceding vehicle following control, a lane centering control, a lane departure prevention control, and the like are mainly performed in appropriate combination. This enables the host vehicle M to drive according to a target route (route map information). Furthermore, in the second driving control mode, lane change control can also be performed. Note that in the second driving control mode, lane change control is automatically performed as appropriate in accordance with the driving environment information of the host vehicle M, even when the driver does not operate the turn signal switch.

[0055] The evacuation mode is a mode for automatically stopping the vehicle M on a roadside or the like, for example, when, 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 manual driving mode or the first driving control mode).

[0056] In addition, in each of the above-mentioned driving modes, the travel_ECU 14 appropriately performs emergency braking (AEB (Autonomous Emergency Braking): collision damage mitigation brake) control against obstacles such as vehicles that are highly likely to collide with the host vehicle M.

[0057] Furthermore, when the traveling_ECU 14 determines that it is difficult to avoid a collision with an obstacle by emergency brake control, it is also possible to perform emergency steering control to avoid a collision with an obstacle instead of or in combination with emergency brake control.

[0058] Next, the lane change control in the driving assistance device 1 will be specifically described.

[0059] In this lane change control, the driving_ECU 14 determines whether or not a lane change is necessary. For example, the driving_ECU 14 determines that a lane change is necessary when the driver operates a turn signal switch during execution of the first driving control mode or the second driving control mode. Alternatively, the driving_ECU 14 determines that a lane change is necessary during execution of the second driving control mode when the host vehicle M is following a preceding vehicle and the vehicle speed of the preceding vehicle is Vf is lower than the set vehicle speed Vs of the host vehicle M by a predetermined amount. Alternatively, the travel_ECU 14 determines that a lane change is necessary when, for example, the second travel control mode is being executed and the vehicle speed V is higher than the set vehicle speed Vs of the host vehicle M by a predetermined amount. Vr When a following vehicle traveling at a speed approaching the rear of the vehicle M, it is determined that a lane change is necessary.

[0060] Furthermore, when it is determined that a lane change is necessary, the traveling_ECU 14 determines whether or not the lane change is possible. For example, the traveling_ECU 14 comprehensively determines various conditions, such as whether or not the section of the road on which the vehicle M is currently traveling is a section where lane changes are permitted, and whether or not there is another vehicle or the like within a set distance (for example, 45 m forward or backward) from the vehicle M in the adjacent lane to which the lane will be changed, to determine whether or not the lane change is possible.

[0061] If it is determined that a lane change is necessary and that a lane change to an adjacent lane is possible, the travel_ECU 14 sets, for example, the center of the adjacent lane to which the lane is to be changed as the target lateral position.

[0062] Furthermore, the traveling_ECU 14 sets a target route for causing the host vehicle M to reach the target lateral position within a set time (for example, within 3 seconds). When setting this target route, the traveling_ECU 14 divides, for example, a section from the lateral position (start lateral position) of the host vehicle M to the target lateral position into, for example, an extraction section (first section) and a steering-back section (second section). The extraction section is, for example, a section from the start lateral position to an intermediate lateral position (an intermediate lateral position between the start lateral position and the target lateral position). This extraction section is mainly a section for moving the host vehicle M to an adjacent lane. The steering-back section is, for example, a section from the intermediate lateral position to the target lateral position. This steering-back section is mainly a section for moving the host vehicle M to the center of the adjacent lane and eliminating a lane-to-lane yaw angle that occurs as a result of the lane change.

[0063] Furthermore, the travel_ECU 14 sets a target route for each divided section using, for example, a preset jerk (rate of change in acceleration) characteristic or the like.

[0064] Then, the traveling_ECU 14 drives the electric power steering motor 35 via the PS_ECU 25 to cause the host vehicle M to travel along the target route.

[0065] Next, we will explain the following inter-vehicle distance control (vehicle speed control) when the host vehicle M following the preceding vehicle starts lane change control. The following inter-vehicle distance control during lane change control differs depending on whether the host vehicle M changes lanes from the driving lane to the passing lane or from the passing lane to the driving lane.

[0066] Here, the term "driving lane" refers to, for example, a lane other than the rightmost lane on a road where vehicles legally drive on the left and there are multiple lanes. The term "passing lane" refers to, for example, a lane on a road where vehicles legally drive on the left and there are multiple lanes. Therefore, on a road with three lanes on each side, as shown in Figure 9-14, the first and second lanes counting from the left are driving lanes, and the third lane is the passing lane. Note that on roads where vehicles legally drive on the right, the definitions of driving lane and passing lane are reversed.

[0067] When the host vehicle M starts to change lanes to the driving lane during following travel, the travel_ECU 14 maintains the target vehicle speed Vt at the time of starting the lane change at least until the lane change is completed. The target vehicle speed Vt can also be maintained for a predetermined time (for example, several seconds) after the lane change is completed.

[0068] Then, after the host vehicle M has finished changing lanes to the driving lane, the travel_ECU 14 basically sets the set vehicle speed Vs as the new target vehicle speed Vt. Furthermore, the travel_ECU 14 sets the target acceleration at by referring to a pre-set map or the like based on the newly set target vehicle speed Vt (and the current vehicle speed V of the host vehicle M). Then, the travel_ECU 14 accelerates the host vehicle M to the target vehicle speed Vt based on the target acceleration at. Note that the map for this target acceleration at is set, for example, so that the target acceleration at increases as the speed difference between the vehicle speed V of the host vehicle M and the target vehicle speed Vt increases.

[0069] However, when setting the new target vehicle speed Vt, the traveling_ECU 14 sets a reference vehicle speed V1 based on a speed in accordance with the traffic flow surrounding the host vehicle M (for example, an average vehicle speed of surrounding vehicles). If the new target vehicle speed Vt is higher than the reference vehicle speed V1, the traveling_ECU 14 corrects the new target vehicle speed Vt to a lower value. Specifically, the traveling_ECU 14 reduces the new target vehicle speed Vt to, for example, the reference vehicle speed V1.

[0070] This allows the host vehicle M to travel at a speed in line with the flow of traffic without being accelerated to an excessive speed even after changing lanes.

[0071] Furthermore, it is possible to delay the time until the host vehicle M, after changing lanes, travels alongside the vehicle that was the preceding vehicle before the lane change. Therefore, it is possible to make the preceding vehicle accurately aware that the host vehicle M has changed lanes. Furthermore, even if the preceding vehicle changes lanes into the driving lane without noticing the presence of the host vehicle M, it is possible to ensure that the host vehicle M has time to apply emergency braking or the like to avoid a collision with the vehicle that has changed lanes.

[0072] The average vehicle speed of the surrounding vehicles can be calculated based on the driving environment information, or can be obtained through road-to-vehicle communication with infrastructure installed on the road.

[0073] In addition, when the new target vehicle speed Vt is equal to or less than the reference vehicle speed V1, the travel_ECU 14 calculates the new target vehicle speed Vt and the vehicle speed of the preceding vehicle. Vf Then, when the speed difference ΔV is equal to or greater than a first threshold value ΔVth1 set in advance, the travel_ECU 14 corrects at least one of the new target vehicle speed Vt and the target acceleration at based on the new target vehicle speed Vt to a decreasing side.

[0074] This makes it possible to delay the time until the host vehicle M, after changing lanes, travels alongside the vehicle that was the preceding vehicle before the lane change. Therefore, it is possible to make the preceding vehicle accurately aware that the host vehicle M has changed lanes. Furthermore, even if the preceding vehicle changes lanes into the driving lane without noticing the presence of the host vehicle M, it is possible to ensure that the host vehicle M has time to apply emergency braking or the like to avoid a collision with the vehicle that has changed lanes.

[0075] In this manner, in this embodiment, when the host vehicle M changes lanes to the driving lane, vehicle speed control is performed to avoid interference with the vehicle that was the preceding vehicle before the lane change.

[0076] After the vehicle speed of the host vehicle M is accelerated to the new target vehicle speed Vt (including after correction) by such vehicle speed control accompanying a lane change to the driving lane, normal following inter-vehicle distance control is performed. That is, when a preceding vehicle is newly recognized ahead of the host vehicle M in the lane after the lane change, the traveling_ECU 14 causes the host vehicle M to travel following the preceding vehicle. Alternatively, when a preceding vehicle is not recognized ahead of the host vehicle M in the lane after the lane change, the traveling_ECU 14 causes the host vehicle M to travel at a constant speed at the set vehicle speed Vs.

[0077] On the other hand, when the host vehicle M starts changing lanes to an overtaking lane while following a preceding vehicle, the traveling_ECU 14 basically sets the set vehicle speed Vs as a new target vehicle speed Vt. Furthermore, the traveling_ECU 14 sets the target acceleration at based on the newly set target vehicle speed Vt (and the current vehicle speed V of the host vehicle M) by referring to a pre-set map or the like. As a result, the traveling_ECU 14 accelerates the host vehicle M to the target vehicle speed Vt based on the target acceleration at. That is, the traveling_ECU 14 accelerates the vehicle speed V of the host vehicle M to the newly set target vehicle speed Vt in parallel with the lane change.

[0078] When changing lanes to an overtaking lane, it is desirable for the host vehicle M to accelerate quickly to overtake the preceding vehicle. Also, when changing lanes to an overtaking lane, even if a following vehicle approaches at high speed from a distance on the overtaking lane, it is desirable for the host vehicle M to accelerate quickly to a vehicle speed that allows it to avoid interference with the following vehicle.

[0079] Therefore, the travel_ECU 14 calculates the new target vehicle speed Vt and the vehicle speed of the preceding vehicle. Vf The travel_ECU 14 calculates a speed difference ΔV between the target vehicle speed Vt and the target acceleration at. If the speed difference ΔV is a predetermined small value, the travel_ECU 14 corrects the new target vehicle speed Vt to an increasing value. The travel_ECU 14 also sets the target acceleration at by referring to a preset map or the like based on the corrected new target vehicle speed Vt. That is, when the target vehicle speed Vt is corrected to an increasing value, the target acceleration at is also corrected to an increasing value.

[0080] However, it is desirable that the upper limit of the upward correction of the new target vehicle speed Vt is the legal speed set for the road. Therefore, when the new target vehicle speed Vt (set vehicle speed Vs) is set to the legal speed, it is desirable to correct only the target acceleration at to the upward side.

[0081] The correction amount for correcting the target vehicle speed Vt and target acceleration at to the increasing side is set based on a pre-set map, etc., so that the smaller the speed difference ΔV, the larger the correction amount, with the upper limit being a value at which the vehicle M can safely change lanes (for example, a value that satisfies the jerk characteristics when changing lanes).

[0082] Incidentally, when a following vehicle is detected during a lane change, it is desirable to accelerate more quickly than when the following vehicle is not detected. In other words, when a following vehicle is detected, it is desirable to accelerate more quickly even when the speed difference ΔV is relatively small than when the following vehicle is detected.

[0083] Therefore, the threshold values ​​for determining whether to correct the target vehicle speed Vt and the target acceleration at to the increasing side are set to different values ​​when a following vehicle is not recognized and when a following vehicle is recognized. That is, the second threshold value Vth2 for the speed difference ΔV when a following vehicle is not recognized is set to a larger value than the third threshold value Vth3 for the speed difference ΔV when a following vehicle is recognized.

[0084] In addition, from the above viewpoint, it is desirable that the correction amount for correcting the target vehicle speed Vt and target acceleration at to the increasing side is set to be relatively larger when a following vehicle is recognized than when a following vehicle is not recognized.

[0085] In this way, in this embodiment, when the host vehicle M changes lanes to the overtaking lane, at least if a following vehicle is recognized on the overtaking lane, vehicle speed control is performed to avoid interference with the following vehicle.

[0086] After the vehicle speed of the host vehicle M is accelerated to the new target vehicle speed Vt (including the corrected target vehicle speed Vt) by the vehicle speed control accompanying the lane change to the driving lane, normal following inter-vehicle distance control is performed. That is, when a preceding vehicle is newly recognized ahead of the host vehicle M in the lane after the lane change, the traveling_ECU 14 causes the host vehicle M to travel following the preceding vehicle. Alternatively, when a preceding vehicle is not recognized ahead of the host vehicle M in the lane after the lane change, the traveling_ECU 14 causes the host vehicle M to travel at a constant speed at the set vehicle speed Vs.

[0087] Thus, in this embodiment, the travel_ECU 14 corresponds to a specific example of a following inter-vehicle distance control means.

[0088] Next, the above-mentioned lane change control will be described with reference to the flowchart of the lane change control routine shown in Fig. 3. This lane change control routine is repeatedly executed by the travel_ECU 14 at set time intervals, for example, while the second travel control mode is selected.

[0089] When the routine starts, the driving_ECU 14 checks in step S101 whether or not there is a need to change lanes at present. That is, the driving_ECU 14 checks, for example, whether or not the driver has operated the turn signal switch, the vehicle speed of the preceding vehicle, Vf is slower than the set vehicle speed Vs of the host vehicle M by a predetermined amount, or is a vehicle speed higher than the vehicle speed V of the host vehicle M by a predetermined amount. Vr Based on whether or not the following vehicle is approaching the host vehicle M, the system determines whether or not it is necessary to change lanes.

[0090] Then, in step S101, if it is determined that there is no need to change lanes (step S101: NO), the traveling_ECU 14 exits the routine.

[0091] On the other hand, if it is determined in step S101 that a lane change is necessary (step S101: YES), the traveling_ECU 14 proceeds to step S102.

[0092] In step S102, the traveling_ECU 14 recognizes the adjacent lane to which the vehicle is to change lanes. That is, the traveling_ECU 14 recognizes the lane markings that separate the adjacent lanes based on the traveling environment information. Furthermore, the traveling_ECU 14 also recognizes whether or not there is another vehicle or the like in the adjacent lane.

[0093] In the next step S103, the traveling_ECU 14 checks whether the lane change condition is satisfied. That is, the traveling_ECU 14 determines whether a lane change is possible based on whether the section of the road on which the host vehicle M is traveling is a section where lane changes are permitted, and whether there is another vehicle in the adjacent lane to which the host vehicle M is to change lanes.

[0094] Then, in step S103, if it is determined that the lane change condition is not met (step S103: NO), the traveling_ECU 14 exits the routine.

[0095] On the other hand, if it is determined in step S103 that the lane change condition is met (step S103: YES), the traveling_ECU 14 proceeds to step S104.

[0096] In step S104, the traveling_ECU 14 sets a target lateral position when the host vehicle M changes lanes. That is, the traveling_ECU 14 sets the center of the adjacent lane calculated based on the left and right lane dividing lines that separate the adjacent lane as the target lateral position.

[0097] In the following step S105, the traveling_ECU 14 sets a target route for the host vehicle M to change lanes to the target lateral position.

[0098] In the following step S106, the traveling_ECU 14 drives the electric power steering motor 35 via the PS_ECU 25 to perform steering control according to the target route.

[0099] When the process proceeds from step S106 to step S107, it is checked whether the host vehicle M has reached the target lateral position.

[0100] Then, in step S107, if it is determined that the host vehicle M has not reached the target lateral position (step S106: NO), the travel_ECU 14 returns to step S106.

[0101] On the other hand, if it is determined in step S107 that the host vehicle M has reached the target lateral position (step S107: YES), the travel_ECU 14 exits the routine.

[0102] Next, vehicle speed control accompanying lane changes during follow-up cruise control will be described with reference to the flowchart showing a vehicle speed control routine shown in Figures 4 to 6. This routine is repeatedly executed at set time intervals by the travel_ECU 14 during follow-up cruise control.

[0103] When the routine starts, the driving_ECU 14 checks in step S201 whether a lane change has started.

[0104] Then, in step S201, if it is determined that a lane change has not started (step S201: NO), the traveling_ECU 14 proceeds to step S202. In step S202, the traveling_ECU 14 continues the control for following the preceding vehicle, and then exits the routine.

[0105] On the other hand, if it is determined in step S201 that a lane change has started (step S201: YES), the traveling_ECU 14 proceeds to step S203. In step S203, the traveling_ECU 14 checks whether the lane to which the host vehicle M is to change lanes is the traveling lane.

[0106] Then, in step S203, if it is determined that the lane to which the lane is to be changed is the driving lane (step S203: YES), the traveling_ECU 14 proceeds to step S204. In step S204, the traveling_ECU 14 performs vehicle speed control to maintain the target vehicle speed Vt at the time of starting the lane change.

[0107] In the following step S205, the traveling_ECU 14 checks whether or not the lane change to the traveling lane of the host vehicle M has been completed.

[0108] Then, in step S205, if it is determined that the lane change has not been completed (step S205: NO), the traveling_ECU 14 returns to step S204.

[0109] On the other hand, if it is determined in step S205 that the lane change has been completed (step S205: YES), the traveling_ECU 14 proceeds to step S206. In step S206, the traveling_ECU 14 checks whether a set time (for example, several seconds) has elapsed since the lane change.

[0110] Then, in step S206, The set time has elapsed If it is determined that the vehicle has not yet reached the predetermined speed (step S206: NO), the traveling_ECU 14 returns to step S204.

[0111] On the other hand, in step S206, The set time has elapsed If it is determined that the target vehicle speed Vt has been reached (step S206: YES), the traveling_ECU 14 proceeds to step S207. In step S207, the traveling_ECU 14 sets, for example, the set vehicle speed Vs as the new target vehicle speed Vt. The traveling_ECU 14 also sets the target acceleration at based on the new target vehicle speed Vt.

[0112] In the following step S208, the traveling_ECU 14 sets a reference vehicle speed V1 based on the average vehicle speed of the surrounding vehicles and the like.

[0113] When the process proceeds from step S208 to step S209, the traveling_ECU 14 checks whether the target vehicle speed Vt is equal to or less than the reference vehicle speed V1.

[0114] Then, in step S209, when it is determined that the target vehicle speed Vt is greater than the reference vehicle speed V1 (step S209: NO), the traveling_ECU 14 proceeds to step S210. In step S210, the traveling_ECU 14 corrects the target vehicle speed Vt to the decreasing side by a predetermined decrease amount, and then proceeds to step S214.

[0115] On the other hand, if it is determined in step S209 that the target vehicle speed Vt is equal to or less than the reference vehicle speed V1, the travel_ECU 14 proceeds to step S211. In step S211, the travel_ECU 14 calculates the speed difference ΔV by subtracting the vehicle speed Vf of the preceding vehicle from the target vehicle speed Vt.

[0116] In the following step S212, the traveling_ECU 14 checks whether the speed difference ΔV is less than a preset first threshold value ΔVth1.

[0117] Then, in step S212, when it is determined that the speed difference ΔV is equal to or greater than the first threshold value ΔVth1 (step S212: NO), the traveling_ECU 14 proceeds to step S213. In step S213, the traveling_ECU 14 corrects the target vehicle speed Vt to a decreasing side by a predetermined decreasing amount. The traveling_ECU 14 can also further correct the target acceleration at based on the corrected target vehicle speed Vt to a decreasing side by a predetermined decreasing amount.

[0118] On the other hand, if it is determined in step S212 that the speed difference ΔV is less than the first threshold value ΔVth1 (step S212: YES), the traveling_ECU 14 proceeds to step S214 without correcting the target vehicle speed Vt (and the target acceleration at).

[0119] When the process proceeds from step S210, step S212, or step S213 to step S214, acceleration control is performed using the new target acceleration at (including the corrected value).

[0120] In the following step S215, the travel_ECU 14 checks whether the vehicle speed V of the host vehicle M has reached the new target vehicle speed Vt (including the corrected speed).

[0121] Then, in step S215, if it is determined that the vehicle speed V of the host vehicle M has not reached the new target vehicle speed Vt, the travel_ECU 14 returns to step S214.

[0122] On the other hand, if it is determined in step S215 that the vehicle speed V of the host vehicle M has reached the new target vehicle speed Vt, the traveling_ECU 14 exits the routine.

[0123] Furthermore, in step S203, if it is determined that the lane to which the vehicle is to change lanes is an overtaking lane (step S203: NO), the traveling_ECU 14 proceeds to step S216.

[0124] In step S216, the traveling_ECU 14 sets, for example, the set vehicle speed Vs as the new target vehicle speed Vt. The traveling_ECU 14 also sets the target acceleration at based on the new target vehicle speed Vt.

[0125] In the following step S217, the traveling_ECU 14 calculates the speed difference ΔV by subtracting the vehicle speed Vf of the preceding vehicle from the target vehicle speed Vt.

[0126] When the process proceeds from step S217 to step S218, the traveling_ECU 14 checks whether or not a following vehicle has been detected in the passing lane to which the lane has been changed.

[0127] Then, in step S218, if it is determined that a following vehicle has not been detected (step S218: NO), the traveling_ECU 14 proceeds to step S219. In step S219, the traveling_ECU 14 checks whether the speed difference ΔV is less than a preset second threshold value ΔVth2.

[0128] If it is determined in step S219 that the speed difference ΔV is less than the second threshold value ΔVth2 (step S219: YES), the traveling_ECU 14 proceeds to step S220. In step S220, the traveling_ECU 14 corrects the target vehicle speed Vt to the increasing side, for example, with the legal speed as the upper limit. In addition, the traveling_ECU 14 corrects the target acceleration at to the increasing side in accordance with the correction of the target vehicle speed Vt to the increasing side. Here, if the legal speed and the target vehicle speed Vt match, or if the speed difference between the legal speed and the target vehicle speed Vt is small, it is difficult to sufficiently correct the target vehicle speed Vt to the increasing side. In such cases, the traveling_ECU 14 individually corrects the target acceleration at to the increasing side.

[0129] On the other hand, if it is determined in step S219 that the speed difference ΔV is equal to or greater than the second threshold value ΔVth2 (step S219: NO), the traveling_ECU 14 proceeds to step S223 without correcting the target vehicle speed Vt and the target acceleration at.

[0130] Furthermore, if it is determined in step S218 that a following vehicle has been detected (step S218: YES), the traveling_ECU 14 proceeds to step S221. In step S221, the traveling_ECU 14 checks whether the speed difference ΔV is less than a preset third threshold value ΔVth3.

[0131] Then, in step S221, when it is determined that the speed difference ΔV is less than the third threshold value ΔVth3 (step S221: YES), the traveling_ECU 14 proceeds to step S222. In step S222, the traveling_ECU 14 corrects the target vehicle speed Vt to the increasing side, for example, with the legal speed as the upper limit. Furthermore, the traveling_ECU 14 corrects the target acceleration at to the increasing side in accordance with the correction of the target vehicle speed Vt to the increasing side. Here, if the legal speed and the target vehicle speed Vt match, or if the speed difference between the legal speed and the target vehicle speed Vt is small, it is difficult to sufficiently correct the target vehicle speed Vt to the increasing side. In such cases, the traveling_ECU 14 individually corrects the target acceleration at to the increasing side.

[0132] On the other hand, if it is determined in step S221 that the speed difference ΔV is equal to or greater than the third threshold value ΔVth3 (step S221: NO), the traveling_ECU 14 proceeds to step S223 without correcting the target vehicle speed Vt and the target acceleration at.

[0133] When the process proceeds from step S219, step S220, step S221, or step S222 to step S223, the travel_ECU 14 calculates the newly set target vehicle speed Vt (including the corrected target vehicle speed Vt) and the newly set target acceleration Acceleration control of the host vehicle M is performed using at (including after correction).

[0134] In the following step S224, the travel_ECU 14 checks whether the vehicle speed V of the host vehicle M has been accelerated to the target vehicle speed Vt.

[0135] Then, in step S224, when it is determined that the vehicle speed V of the host vehicle M has not been accelerated to the target vehicle speed Vt (step S224: NO), the travel_ECU 14 returns to step S218.

[0136] On the other hand, if it is determined in step S224 that the vehicle speed V of the host vehicle M has been accelerated to the target vehicle speed Vt (step S224: YES), the traveling_ECU 14 proceeds to step S225. In step S225, the traveling_ECU 14 checks whether the host vehicle M has completed changing lanes to the overtaking lane.

[0137] Then, in step S225, if it is determined that the lane change has not been completed (step S225: NO), the travel_ECU 14 waits as is.

[0138] On the other hand, if it is determined in step S225 that the lane change has been completed (step S225: YES), the traveling_ECU 14 exits the routine.

[0139] According to this embodiment, when the host vehicle M starts to change lanes into the driving lane while traveling under follow-up travel control, the travel_ECU 14 maintains the target vehicle speed Vt at the start of the lane change at least until the lane change is completed, and then sets the set vehicle speed Vs to a new target vehicle speed Vt and sets a target acceleration at based on the new target vehicle speed Vt, thereby accelerating the host vehicle M (see the solid line in Figure 7).

[0140] This makes it possible to delay the time until host vehicle M, after changing lanes, travels alongside vehicle A, which was the preceding vehicle before changing lanes (see the relationship between host vehicle M and vehicle A in FIGS. 9 and 10). Therefore, it is possible to make the preceding vehicle A accurately aware that host vehicle M has changed lanes. Furthermore, even if the preceding vehicle A changes lanes into the driving lane without noticing the presence of host vehicle M (see FIG. 11), it is possible to ensure that host vehicle M has time to apply emergency braking or the like to avoid a collision with vehicle A that has changed lanes.

[0141] Furthermore, after changing lanes to the driving lane, if the new target vehicle speed Vt is higher than the average vehicle speed (reference vehicle speed V1) of the vehicles surrounding the host vehicle M, the traveling_ECU 14 corrects the new target vehicle speed Vt to a lower side.

[0142] This allows the host vehicle M to travel at a vehicle speed V in line with the flow of traffic without being accelerated to an excessive speed even after changing lanes (see the dashed line in Figure 7).

[0143] In addition, after changing lanes to the driving lane, the driving_ECU 14 the goal Vehicle speed Vt is equal to or less than the average vehicle speed (reference vehicle speed V1), and the goal When the speed difference ΔV between the vehicle speed Vt and the speed of the preceding vehicle is equal to or greater than a predetermined first threshold ΔVth1, at least one of the new target vehicle speed Vt or the target acceleration at based on the new target vehicle speed Vt is corrected to a decreasing side (see the dashed line and the dashed double-dashed line in Figure 7).

[0144] This allows a delay in the time it takes for the host vehicle M, after changing lanes, to travel alongside the vehicle that was the preceding vehicle before the lane change. Therefore, the preceding vehicle can be made to accurately recognize that the host vehicle M has changed lanes. Furthermore, even if the preceding vehicle changes lanes into the driving lane without noticing the presence of the host vehicle M, the host vehicle M can have enough time to avoid a collision with the vehicle that changed lanes by applying emergency braking or the like.

[0145] In addition, when the host vehicle M starts to change lanes to an overtaking lane while traveling under the following travel control, the travel_ECU 14 Vs is set as a new target vehicle speed, and a target acceleration at based on the new target vehicle speed is set, and the host vehicle M is accelerated in parallel with the lane change (see the solid line in FIG. 8).

[0146] As a result, when changing lanes to the passing lane, the vehicle can quickly accelerate and overtake the preceding vehicle, vehicle A (see Figures 12 and 13).

[0147] In this case, the travel_ECU 14 calculates the new target vehicle speed Vt and the vehicle speed of the preceding vehicle. Vf When the speed difference ΔV between the target vehicle speed Vt and the set vehicle speed Vt is smaller than a predetermined value, the travel_ECU 14 Vs The vehicle speed is corrected to the above value, and the target acceleration at is corrected to an increasing value.

[0148] This makes it possible to accurately achieve rapid acceleration. At this time, by making the correction amounts for the new target vehicle speed Vt and the new target acceleration at larger when a following vehicle is detected (see the two-dot chain line in FIG. 8) than when no following vehicle is detected (see the one-dot chain line in FIG. 8), it is possible to accurately prevent interference with the following vehicle B (see FIG. 14).

[0149] In the above-described embodiment, the image recognition_ECU 13, the driving_ECU 14, the CP_ECU 21, the E / G_ECU 22, the T / M_ECU 23, the BK_ECU 24, the PS_ECU 25, etc. are configured by well-known microcomputers equipped with a CPU, RAM, ROM, a non-volatile storage unit, etc., and their peripheral devices. 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 by logic circuits or analog circuits, and the processing of various programs may be realized by electronic circuits such as FPGAs.

[0150] The invention described in the above embodiments is not limited to these 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 multiple constituent elements.

[0151] For example, the above-described vehicle speed control is not limited to when the second driving control mode is selected, but can also be performed when the first driving control mode is selected.

[0152] Furthermore, for example, if the stated problem can be solved and the stated effect can be obtained even if some of the constituent elements are deleted from all the constituent elements shown in the above form, the configuration from which these constituent elements are deleted can be extracted as an invention. [Explanation of symbols]

[0153] 1. Driving assistance devices 10...Camera unit 11...Stereo camera 11a ... Main camera 11b ... Sub camera 12 … IPU 13...Image Recognition_ECU 14 … Driving_ECU 21 … CP_ECU 22 ... E / G_ECU 23 ... Transmission ECU 24 … BK_ECU 25 … PS_ECU 31...HMI 32 ... Throttle actuator 33... Hydraulic control circuit 34... Brake actuator 35... Electric power steering motor 36 ... Locator unit 36a … GNSS sensor 36b ... Road map DB 37lf ... Left front side sensor 37lr ... Left rear side sensor 37rf ... Right front side sensor 37rr ... Right rear side sensor M: Vehicle (own vehicle)

Claims

1. a driving environment recognition means for recognizing driving environment information outside the vehicle; and a following vehicle distance control means for performing a following control to make the host vehicle follow the preceding vehicle at a target vehicle speed set in accordance with the vehicle speed of the preceding vehicle when a preceding vehicle is recognized ahead of the host vehicle based on the driving environment information and the vehicle speed of the preceding vehicle is lower than a set vehicle speed input by the driver, and for performing a constant speed traveling control to make the host vehicle travel at a constant speed by setting the set vehicle speed as the target vehicle speed when a preceding vehicle is not recognized ahead of the host vehicle, The following vehicle distance control means, when the host vehicle starts to change lanes into a driving lane while traveling under the following travel control, maintains the target vehicle speed set in accordance with the vehicle speed of the preceding vehicle at least until the lane change is completed, and then, after a set time has elapsed, newly sets the target vehicle speed to the set vehicle speed, and sets a target acceleration based on the speed difference between the newly set target vehicle speed and the vehicle speed of the host vehicle, thereby accelerating the host vehicle.

2. The vehicle driving assistance device of claim 1, characterized in that, after changing lanes into the driving lane, when the new target vehicle speed is higher than the average vehicle speed of vehicles surrounding the host vehicle, the following vehicle distance control means corrects the new target vehicle speed to a lower side, and sets the target acceleration based on the speed difference between the corrected new target vehicle speed and the vehicle speed of the host vehicle.

3. 2. The vehicle driving assistance device according to claim 1, wherein the following vehicle distance control means corrects at least one of the new target vehicle speed or the target acceleration based on the new target vehicle speed to a decreasing side when, after changing lanes to the driving lane, the new target vehicle speed is equal to or lower than the average vehicle speed of the vehicles surrounding the subject vehicle and the speed difference between the new target vehicle speed and the speed of the preceding vehicle is equal to or higher than a predetermined first threshold value.

4. 4. A vehicle driving assistance device as claimed in claim 1, wherein the following vehicle distance control means sets the set vehicle speed to a new target vehicle speed when the host vehicle starts changing lanes to an overtaking lane while traveling under the following travel control, and sets the target acceleration based on the new target vehicle speed, thereby accelerating the host vehicle in parallel with the lane change.

5. 5. A vehicle driving assistance device according to claim 4, wherein the following vehicle distance control means sets the new target vehicle speed to be equal to or higher than the set vehicle speed when a following vehicle is recognized in the passing lane after starting a lane change to the passing lane.

Images