JP6381069B2 - Vehicle driving support control device - Google Patents

Description

  The present invention relates to a driving support control device for a vehicle that assists driving by adding a yaw moment by a braking force to a vehicle when a driver avoids an obstacle on a lane.

  In recent years, in vehicles such as automobiles, various driving support control devices that recognize driving environments, improve safety, and support driver driving have been developed and put into practical use. For example, in Japanese Patent Application Laid-Open No. 2006-193156 (hereinafter referred to as Patent Document 1), when it is determined that the host vehicle is likely to depart from the traveling lane, and it is determined that the host vehicle is likely to depart from the traveling lane. Discloses a technology of a lane departure prevention device that generates a yaw moment in a direction to avoid departure based on a difference in braking force between left and right wheels.

JP 2006-193156 A

  By the way, in order to prevent the departure from the driving lane, it is possible to apply the technology of the lane departure prevention device disclosed in Patent Document 1 described above. However, the driving environment varies, for example, the obstacle ahead of the host vehicle. In the situation where there is an object and this obstacle is avoided by moving to an adjacent lane by steering, there is a problem that it cannot be dealt with only by the technology of the lane departure prevention device described above. The steering for avoiding the obstacle in the forward direction is the first steering performed to avoid the obstacle, the second steering performed so as not to go to the opposite side of the obstacle after avoiding the obstacle, and the original lane. This is performed by a third steering operation performed to return to step S2. In this series of steering operations, if the first steering is delayed, the steering wheel operation is too large, too small, or inappropriate, it is not only possible to effectively prevent a deviation from an adjacent lane, but also an obstacle. Is not properly performed, the vehicle behavior becomes unstable, and the subsequent second and third steering operations are delayed and difficult to perform smoothly.

  The present invention has been made in view of the above circumstances. Even if there is an obstacle ahead of the host vehicle and the obstacle is moved to an adjacent lane by steering, An object of the present invention is to provide a driving support control device for a vehicle that can prevent a departure from an adjacent lane and avoid an obstacle appropriately and smoothly in operation.

One aspect of the vehicle driving support apparatus according to the present invention is an environment information detecting unit that detects at least an obstacle, a lane, and own vehicle position information, and an understeer state that detects an understeer state of the vehicle in return steering from avoidance steering of a driver. A state detection means, an avoidance steering intention determination means for determining the driver's intention of avoidance steering with respect to the obstacle, and a prediction of an outward departure from the destination lane in which the host vehicle moves to avoid the obstacle Lane departure predicting means that performs the avoidance steering with respect to the obstacle in the understeer state of the vehicle in the return steering from the driver's avoidance steering, and the vehicle is expected to deviate from the destination lane to the outside. And a yaw moment adding means for calculating and adding a yaw moment for suppressing the understeer state of the vehicle to the vehicle. Understeer detecting means is a negative threshold below the value a value obtained by adding the multiplication value of the coefficient set in advance to the steering angle and the steering angular velocity obtained by subtracting the target yaw rate and from the actual yaw rate be greater than or equal to zero has been set in advance When an understeer state of the vehicle is detected, a value obtained by adding a multiplication value of the coefficient and the steering angular velocity to the steering angle is less than zero, and a value obtained by subtracting the target yaw rate from the actual yaw rate is When the value is equal to or greater than the set positive threshold value, the understeer state of the vehicle is detected.

  According to the vehicle driving support control device of the present invention, even if there is an obstacle in front of the host vehicle and the obstacle is moved to an adjacent lane by steering, During operation, it becomes possible to prevent deviation from adjacent lanes and avoid obstacles with good responsiveness and smoothness.

1 is a schematic configuration diagram of a vehicle driving support control apparatus according to an embodiment of the present invention. It is a functional block of the control unit which concerns on one Embodiment of this invention. It is a flowchart of the driving assistance control program of the vehicle concerning one embodiment of the present invention. It is characteristic explanatory drawing of the 1st target yaw moment with respect to the absolute value of the yaw rate deviation which concerns on one Embodiment of this invention, and 1st target total braking force. It is characteristic explanatory drawing of the 2nd target yaw moment and the 2nd target total braking force with respect to lane departure prediction time concerning one embodiment of the present invention. FIG. 6A shows an example of control according to an embodiment of the present invention, and FIG. 6A shows a state in which a host vehicle traveling in a traveling lane moves to an adjacent lane, avoids an obstacle, and returns to the traveling lane again. FIG. 6 (b) is an explanatory diagram showing an example, and understeer state determination at the time of yaw rate return steering in consideration of the steering angular velocity according to this embodiment used in the control of FIG. 6 (a) and conventional control (normal target yaw rate and It is comparison explanatory drawing of the understeer state determination by the comparison of an actual yaw rate.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
In FIG. 1, reference numeral 1 denotes a vehicle such as an automobile (own vehicle), and a driving support control device 10 is mounted on the vehicle 1. The driving support control device 10 includes an image recognition device 21 that detects travel environment information (to be described later), a vehicle speed sensor 22 that detects a vehicle speed V, a yaw rate sensor 23 that detects an actual yaw rate (actual yaw rate) γ, and steering. A handle angle sensor 24 for detecting the angle θH is connected. The control signals set by the control unit 11 (brake fluid pressures Pfi, Pfo, Pri, Pro of each wheel: hereinafter, the suffix “fi” is the front wheel turning inner wheel side, “fo” is the front wheel turning outer wheel side, “ri”. Output the rear wheel turning inner wheel side and “ro” indicates the rear wheel turning outer wheel side) to the brake drive unit 12 composed of a hydraulic unit including a pressure source, a pressure reducing valve, a pressure increasing valve, etc. The brake fluid pressure to be generated is generated by a wheel cylinder of each wheel (not shown).

  Solid state imaging such as a charge coupled device (CCD) that is attached to the image recognition device 21 at a certain interval in front of the ceiling inside the vehicle interior, takes a stereo image of objects outside the vehicle from different viewpoints, and outputs the captured image information. Image information is input from a pair of left and right CCD cameras (stereo cameras) 21 a using the elements, and the vehicle speed V is input from the vehicle speed sensor 22. Based on these information, the image recognition device 21 recognizes forward information such as three-dimensional object data and white line (lane line) data in front of the host vehicle based on image information from the stereo camera 21a, and these recognition information. Based on the above, the traveling lane of the host vehicle 1 is estimated. Further, the image recognition device 21 checks whether or not a three-dimensional object exists on the traveling lane of the host vehicle 1, and if it exists, recognizes the latest one as an obstacle.

  Here, the image recognition device 21 performs processing of image information from the stereo camera 21a, for example, as follows. First, distance information is generated based on the principle of triangulation from a corresponding positional deviation amount for a pair of stereo images obtained by imaging the traveling direction of the host vehicle with the stereo camera 21a. Then, a known grouping process is performed on the distance information, and the distance information obtained by the grouping process is compared with preset three-dimensional road shape data, three-dimensional object data, etc. ) Extract data, side data such as guardrails and curbs that exist along the road, and three-dimensional object data such as vehicles.

  Furthermore, the image recognition device 21 estimates the travel lane of the host vehicle 1 based on white line (lane line) data, side wall data, the traveling direction of the host vehicle, and the like, and the nearest three-dimensional object existing in front of the traveling lane of the host vehicle 1. An object is extracted (detected) as an obstacle. When an obstacle is detected, as the obstacle information, the relative distance d between the own vehicle and the obstacle, the moving speed Vf of the obstacle (= (change ratio of the relative distance d) + the own vehicle speed V). ), Obstacle deceleration af (= differential value of obstacle movement speed Vf), lap ratio Rr in the width direction between the obstacle and the host vehicle (= the width of the host vehicle 1 overlaps the width of the obstacle) The ratio to the width of the host vehicle 1 (see FIG. 6A)) is calculated.

  Further, as shown in FIG. 6A, the image recognition device 21 moves the current vehicle 1 in order to avoid the obstacle and the current traveling direction of the own vehicle 1 (straight direction centered on the camera position). The angle formed by the outer lane line (hereinafter referred to as the outer lane line) of the destination lane (adjacent lane) is calculated as the intersection angle α. Further, the distance in the lane width direction from the current position of the host vehicle 1 to the outer lane marking is calculated as D.

  Thus, the obstacle data and lane data calculated by the image recognition device 21 are output to the control unit 11. Thus, the image recognition device 21 and the stereo camera 21a are provided as environment information detection means. In this embodiment, the shape of obstacle data and lane data is recognized based on an image from a stereo camera. However, other information is obtained based on image information from a monocular camera and a color camera. It may be.

  Then, the control unit 11 receives the above-described signals, and changes the understeer state of the vehicle in the return steering from the driver's avoidance steering according to the vehicle driving support control program described later to the steering angle θH and the steering angular velocity (dθH / dt) according to the case, the vehicle behavior is detected for each case, the driver's intention of avoidance steering with respect to the obstacle is determined, and the own vehicle 1 moves to avoid the obstacle, the outer section of the destination lane A driver deviates from the outer lane of the destination lane when the driver performs an evasive steering with respect to an obstacle in an understeer state of the vehicle in the return steering from the avoidance steering of the driver in anticipation of departure from the line. When the vehicle is expected to deviate, the yaw moment and braking force that suppress the understeer state of the vehicle are calculated and added to the host vehicle 1.

  Therefore, as shown in FIG. 2, the control unit 11 includes a target yaw rate calculation unit 11a, an understeer state determination unit 11b, a return steering determination unit 11c, an obstacle avoidance steering determination unit 11d, a predicted lane departure time calculation unit 11e, and an outer side. A lane marking departure determination unit 11f, a target yaw moment / target total braking force calculation unit 11g, and each wheel brake hydraulic pressure calculation unit 11h are mainly configured.

The target yaw rate calculation unit 11 a receives the vehicle speed V from the vehicle speed sensor 22 and the steering angle θH from the steering wheel angle sensor 24. Then, for example, the target yaw rate γref is calculated by the following equation (1) and output to the understeer state determination unit 11b and the target yaw moment / target total braking force calculation unit 11g.
γref = (1 / (1 + A · V ² )) · (V / l) · (θH / n) (1)
Here, A is a stability factor, l is a wheel base, and n is a steering gear ratio.

The understeer state determination unit 11b receives the actual yaw rate γ from the yaw rate sensor 23, the steering angle θH from the steering wheel angle sensor 24, and the target yaw rate γref from the target yaw rate calculation unit 11a. Then, the understeer state of the vehicle is determined by dividing into the following two formulas (2) and (3) according to the steering angle θH and the steering angular velocity (dθH / dt).
・ When θH + K・ (dθH / dt) ≧ 0,
When γ−γref ≦ −C1, the vehicle is determined to be in an understeer state. ... (2)
・ If θH + K・ (dθH / dt) <0,
When γ−γref ≧ + C2, the vehicle is determined to be in an understeer state. ... (3)
Here, C1 and C2 are positive values and are threshold values set in advance through experiments and calculations. K is a coefficient set in advance through experiments and calculations.

  That is, in order to determine each of the understeer, oversteer, and neutral steer states of the vehicle behavior at the current (current) steering angle θH, it is possible to determine by simply classifying the states according to the steering angle θH. However, in the present embodiment, the vehicle behavior is determined by considering the steering angular velocity (dθH / dt) of the driver (adding the steering angle θH and the steering angular velocity (dθH / dt)) and Considering the driver's steering operation, the occurrence of vehicle behavior can be detected early and with good response.

  Thus, the result determined by the understeer state determination unit 11b (result of determination of whether or not the understeer state is present) is output to the target yaw moment / target total braking force calculation unit 11g. Thus, the understeer state determination unit 11b is provided with the function of an understeer state detection unit.

  The return steering determination unit 11 c receives the steering angle θH from the handle angle sensor 24. Then, the signs of the steering angle θH and the steering angular velocity (dθH / dt) are compared. When the signs are different from each other, the return steering and the turnback steering are determined, and the determination result is a target yaw moment / target total braking force calculation unit. To 11g. Thus, the return steering determination unit 11c is provided with the function of the understeer state detection means.

  The obstacle avoidance steering determination unit 11d receives obstacle data (particularly, the presence / absence of an obstacle, the lap ratio Rr in the width direction between the obstacle and the host vehicle) from the image recognition device 21. Then, for example, when the lap rate Rr is 0, it is determined that sufficient avoidance steering with respect to the obstacle is performed and the driver has intention to avoid steering, and the determination result is calculated as the target yaw moment / target total braking force. To the unit 11g. Thus, the obstacle avoidance steering determination unit 11d is provided as an avoidance steering intention determination unit. When there is no obstacle, the lap rate Rr = 0, and it is determined that sufficient avoidance steering has been performed.

The estimated lane departure time calculation unit 11e receives a lane, a lane line, and own vehicle position information (specifically, a destination lane (adjacent to which the host vehicle 1 moves to avoid an obstacle) from the image recognition device 21. ), The intersection angle α of the vehicle 1 with the outer lane line, the distance D) in the lane width direction from the current position of the host vehicle 1 to the outer lane line, and the vehicle speed V are input from the vehicle speed sensor 22. Then, in order to avoid the obstacle, the vehicle 1 moves and predicts a departure from the outside lane line of the destination lane to the outside. For example, the estimated lane departure time Tttlc is calculated by the following equation (4). The calculated value is output to the outer lane marking departure determination unit 11f and the target yaw moment / target total braking force calculation unit 11g.
Tttlc = D / (V · sin (α)) (4)

  The outer lane departure determination unit 11f receives the predicted lane departure time Tttlc from the predicted lane departure time calculation unit 11e. Then, the predicted lane departure time Tttlc is compared with the set time Tc set in advance through experiments and calculations. When the estimated lane departure time Tttlc is less than or equal to the set time Tc, the host vehicle 1 moves from the destination lane. It is determined that there is a possibility of deviating outward, and the determination result is output to the target yaw moment / target total braking force calculation unit 11g. As described above, the predicted lane departure time calculation unit 11e and the outer lane departure determination unit 11f are provided as lane departure prediction means.

  The target yaw moment / target total braking force calculation unit 11g receives the actual yaw rate γ from the yaw rate sensor 23, the target yaw rate γref from the target yaw rate calculation unit 11a, and the understeer state determination result of the vehicle from the understeer state determination unit 11b. Is input, the determination result of the return steering and the turnback steering is input from the return steering determination unit 11c, and the determination result of the driver's avoidance steering intention (sufficient avoidance steering) is input from the obstacle avoidance steering determination unit 11d, The predicted lane departure time Tttlc is input from the predicted lane departure time calculation unit 11e, and the determination result of whether or not the host vehicle 1 is likely to deviate from the destination lane is input from the outer lane departure determination unit 11f. Then, when the driver performs avoidance steering on the obstacle in the understeer state of the vehicle in the return steering from the avoidance steering of the driver, and the own vehicle 1 is expected to deviate outward from the outer lane line of the destination lane. In addition, for example, as shown in FIG. 4, a map of the first target yaw moment Mzt1 with respect to the absolute value | Δγ | (= | γ−γref |) of the yaw rate deviation of the characteristic set in advance by experiment / calculation or the like To set the first target yaw moment Mzt1. Similarly, for example, referring to a map of the second target yaw moment Mzt2 with respect to the predicted lane departure time Tttlc having characteristics set in advance by experiment / calculation as shown in FIG. Set Mzt2.

Thus, the final target yaw moment Mzt is calculated by adding the set first target yaw moment Mzt1 and second target yaw moment Mzt2.
Mzt = Mzt1 + Mzt2 (5)

  In addition, the target yaw moment / target total braking force calculating unit 11g performs avoidance steering with respect to the obstacle in the vehicle understeer state in the return steering from the avoidance steering of the driver, so that the own vehicle 1 is in the destination lane. When a deviation from the outer lane line is expected, for example, as shown in FIG. 4, the first target for the absolute value | Δγ | of the yaw rate deviation of the characteristic set in advance by experiment / calculation or the like The first target total braking force Fdt1 is set with reference to the map of the total braking force Fdt1. Similarly, for example, referring to a map of the second target total braking force Fdt2 with respect to the predicted lane departure time Tttlc having characteristics set in advance by experiment / calculation as shown in FIG. Set the braking force Fdt2.

Thus, the final target total braking force Fdt is calculated by adding the set first target total braking force Fdt1 and second target total braking force Fdt2.
Fdt = Fdt1 + Fdt2 (6)
Here, the characteristics of the map of the first target yaw moment Mzt1 and the first target total braking force Fdt1 with respect to the absolute value | Δγ | of the yaw rate deviation in FIG. 4 will be described. Both the first target yaw moment Mzt1 and the first target total braking force Fdt1 are set to increase as the absolute value | Δγ | of the yaw rate deviation increases, and the vehicle behavior deviated from the steering of the driver can be corrected.

  At this time, the area until the absolute value of the yaw rate deviation | Δγ | reaches Pγ0 is only the first target yaw moment Mzt1, and the vehicle behavior is optimized (see Pγ1). In a region where the absolute value of deviation | Δγ | exceeds Pγ0, in addition to the first target yaw moment Mzt1, the first target total braking force Fdt1 is also added to decelerate the vehicle so that the vehicle behavior can be stabilized. (See Pγ2).

  The characteristics of the map of the second target yaw moment Mzt2 and the second target total braking force Fdt2 with respect to the predicted lane departure time Tttlc in FIG. 5 will be described. Both the second target yaw moment Mzt2 and the second target total braking force Fdt2 are set to a larger value as the predicted lane departure time Tttlc becomes smaller and the risk of departure becomes higher. The deviation of the moving lane from the outside lane to the outside is surely prevented.

  At this time, in the region where the predicted lane departure time Tttlc until the predicted lane departure time Tttlc reaches Pt0 is large, the second target yaw moment Mzt2 alone prevents the departure from the lane (Pt1). In the region where the predicted lane departure time Tttlc is shorter than Pt0 and the risk of lane departure increases, the vehicle is operated with the second target total braking force Fdt2 in addition to the second target yaw moment Mzt2. The vehicle decelerates and can reliably prevent deviation from the lane (see Pt2).

  The final target yaw moment Mzt and target total braking force Fdt calculated by the target yaw moment / target total braking force calculation unit 11g are output to each wheel brake hydraulic pressure calculation unit 11h.

Each wheel brake hydraulic pressure calculation unit 11h receives the final target yaw moment Mzt and the target total braking force Fdt from the target yaw moment / target total braking force calculation unit 11g. Then, for example, the brake fluid pressure Pfi on the front wheel turning inner wheel side is calculated by the following equation (7), the brake fluid pressure Pfo on the front wheel turning outer wheel side is calculated by the equation (8), and the rear wheel turning is calculated by the equation (9). The brake fluid pressure Pri on the inner wheel side is calculated, the brake fluid pressure Pro on the rear wheel turning outer wheel side is calculated by the equation (10), and is output to the brake drive unit 12.
Pfi = (Mzt · 2 · (Dm / df) + Fdt · (Df / 2)) · Cf (7)
Pfo = Fdt · (Df / 2) · Cf (8)
Pri = (Mzt · 2 · ((1-Dm) / dr)
+ Fdt · ((1-Df) / 2)) · Cr (9)
Pro = Fdt. ((1-Df) / 2) .Cr (10)
Here, Dm is the front shaft distribution ratio of the yaw moment, Df is the front shaft distribution ratio of the total braking force, df is the front shaft tread, dr is the rear shaft tread, and Cf is the brake fluid pressure / braking force coefficient (predetermined value) of the front wheels. ), Cr is the rear wheel brake fluid pressure / braking force coefficient (predetermined value).

  That is, the braking wheel that generates the target yaw moment Mzt for correcting the vehicle behavior in the understeer state is performed by applying a braking force to the turning inner wheel side. In this way, the yaw moment adding means is configured by the target yaw moment / target total braking force calculating unit 11g and each wheel brake hydraulic pressure calculating unit 11h.

  Hereinafter, the driving support control executed by the driving support control device 10 will be described based on the flowchart of FIG.

  First, in step (hereinafter, abbreviated as “S”) 101, the target yaw rate calculation unit 11a calculates the target yaw rate γref by, for example, the above-described equation (1).

  Next, proceeding to S102, the understeer state determination unit 11b determines the understeer state in consideration of the steering angular velocity (dθH / dt) by the above-described equations (2) and (3).

  Then, the process proceeds to S103, and the control unit 11 proceeds to S104 if the determination by the understeer state determination unit 11b is the understeer state, and if it is not the understeer state, the control unit 11 directly exits the routine.

  When the understeer state is determined in S103 and the process proceeds to S104, it is determined whether the return steering determination unit 11c determines the return steering or the reverse steering. If the return steering or the reverse steering is determined, the process proceeds to S105. If it is not determined that the return steering or the return steering is performed, the routine is directly exited.

  When it is determined in S104 that the steering is a return steering or a turning-back steering and the process proceeds to S105, the obstacle avoidance steering determination unit 11d has a lap rate Rr of, for example, 0 and sufficient avoidance steering for the obstacle is performed. It is determined whether or not there is an intention to avoid steering.

  As a result of the determination in S105, if it is determined that sufficient avoidance steering is performed, the process proceeds to S106, and if it is determined that sufficient avoidance steering is not performed, the routine is directly exited. .

  When it is determined in S105 that sufficient avoidance steering is performed and the process proceeds to S106, the lane departure prediction time calculation unit 11e uses the vehicle 1 to avoid an obstacle according to, for example, the above equation (4). The predicted lane departure time Tttlc is calculated in anticipation of a departure from the outer lane of the destination lane to which the vehicle moves.

  Next, in S107, the outside lane departure judgment unit 11f compares the predicted lane departure time Tttlc with the set time Tc set in advance through experiments and calculations, and the predicted lane departure time Tttlc is set to the set time. It is determined whether or not it is determined that there is a possibility that the host vehicle 1 will deviate from the destination lane at Tc or less (Tttlc ≦ Tc).

  As a result of the determination in S107, if there is a possibility that the own vehicle 1 may deviate from the destination lane, the process proceeds to S108, and if there is no possibility of deviating, the routine is directly exited.

  If it is determined in S107 that the host vehicle 1 may deviate from the destination lane and the process proceeds to S108, the target yaw moment / target total braking force calculation unit 11g calculates the following equation (5): A target yaw moment Mzt is calculated.

  Next, the process proceeds to S109, and the target yaw moment / target total braking force calculation unit 11g calculates the target total braking force Fdt by the above-described equation (6).

  Then, the process proceeds to S110, where each wheel brake fluid pressure calculation unit 11h calculates the brake fluid pressure Pfi on the front wheel turning inner wheel side by the above-described equation (7), and the brake fluid on the front wheel turning outer wheel side by the equation (8), for example. The pressure Pfo is calculated, the brake fluid pressure Pri on the rear wheel turning inner wheel side is calculated by the equation (9), the brake fluid pressure Pro on the rear wheel turning outer wheel side is calculated by the equation (10), and output to the brake drive unit 12. And exit the program.

  As described above, according to the present embodiment, the vehicle understeer state in the return steering from the avoidance steering of the driver is detected by dividing the vehicle behavior according to the steering angle θH and the steering angular velocity (dθH / dt). Then, the driver's intention of avoidance steering with respect to the obstacle is determined, and the driver's avoidance steering is predicted by predicting a departure from the outer lane line of the destination lane in which the host vehicle 1 moves to avoid the obstacle. When the driver performs avoidance steering with respect to the obstacle in the understeer state of the vehicle in the return steering from the vehicle, and the vehicle 1 is expected to deviate from the outside lane line of the destination lane, the vehicle understeer state is changed. The yaw moment and braking force to be suppressed are calculated and added to the host vehicle 1. For this reason, even if there is an obstacle in front of the host vehicle and the obstacle is moved to an adjacent lane by steering to avoid the obstacle, the first steering performed to avoid the obstacle, From the adjacent lane in a series of steering operations performed by the second steering performed so as not to go too far to the opposite side of the obstacle after avoiding the obstacle, and the third steering performed to return to the original lane Thus, it is possible to smoothly avoid the obstacles and avoid the obstacles with good responsiveness and smoothly, and it is possible to bring out the danger avoidance performance to the limit.

  For example, as shown in FIG. 6A, a case will be described in which the host vehicle 1 traveling in a traveling lane moves to an adjacent lane, avoids an obstacle, and returns to the traveling lane again.

  When the driver is driving in the driving lane, sufficient avoidance steering is performed so that the lap rate Rr becomes 0 in an attempt to avoid the obstacle, and when the driver performs return steering, the vehicle behavior at this time The determination of the understeer state is not a determination based on the target yaw rate based on the steering angle θH, which is indicated by the solid line in FIG. 6B, but a yaw rate (dθH / dt) taking into account the steering angular velocity (dθH / dt). Since this is performed by the broken line in FIG. 6B, the understeer state is detected earlier than normal (point P1 → point P′1 in FIG. 6B). Then, when the deviation from the moving lane to avoid the obstacle is determined by the estimated lane departure time Tttlc, the absolute value of the yaw rate deviation | Δγ | and the estimated lane departure time Tttlc at that time, The yaw moment and braking force that suppress the understeer state of the vehicle are calculated and applied to the host vehicle 1 (the right wheel side brake in FIG. 6B, the yaw moment M1 in FIG. 6A). Thus, the operation of the brake control for the second steering performed so as not to go too far to the opposite side of the obstacle is accelerated. Then, after the second steering, when the driver performs the third steering to return to the original traveling lane of the host vehicle 1 again, the brake control operation for the second steering is accelerated, In addition, the determination of the understeer state using the yaw rate in consideration of the steering angular velocity (dθH / dt) as the steering angle θH, the obstacle in the traveling lane to which the host vehicle 1 is going to return, the situation of departure from the lane, and the steering angle θH (FIG. 6 ( b), point P2 → point P′2), the brake control operation for the third steering is also accelerated by the steering state of the driver (the left wheel side brake in FIG. 6B, the yaw in FIG. 6A). Moment M2). In FIG. 6B, the alternate long and short dash line indicates the actual yaw rate with respect to the normal target yaw rate (target yaw rate based on the steering angle θH).

DESCRIPTION OF SYMBOLS 1 Own vehicle 10 Driving assistance control apparatus 11 Control unit 11a Target yaw rate calculation part 11b Understeer state determination part (understeer state detection means)
11c Return steering determination unit (understeer state detection means)
11d Obstacle avoidance steering determination unit (avoidance steering intention determination means)
11e Lane departure prediction time calculation unit (lane departure prediction means)
11f Outer lane marking departure determination unit (lane departure prediction means)
11g Target yaw moment / target total braking force calculation unit 11h Brake hydraulic pressure calculation unit for each wheel (yaw moment adding means)
12 Brake drive (yaw moment adding means)
21 Image recognition device (environmental information detection means)
21a Stereo camera (environmental information detection means)
22 Vehicle speed sensor 23 Yaw rate sensor 24 Handle angle sensor

Claims (4)

Environmental information detecting means for detecting at least obstacles, lanes and own vehicle position information;
Understeer state detection means for detecting an understeer state of the vehicle in return steering from avoidance steering of the driver;
Avoidance steering intention determination means for determining a driver's intention of avoidance steering with respect to the obstacle,
Lane departure prediction means for predicting a departure from the destination lane, in which the host vehicle moves to avoid the obstacle,
When the driver performs avoidance steering on the obstacle while the vehicle is understeering from return steering from avoidance steering of the driver, and the own vehicle is expected to deviate from the destination lane, the vehicle A yaw moment adding means for calculating and adding a yaw moment to suppress the understeer state to the vehicle,
The understeer state detecting means is such that a value obtained by adding a multiplication value of a coefficient set in advance to the steering angle and the steering angular velocity is not less than zero, and a value obtained by subtracting the target yaw rate from the actual yaw rate is not more than a preset negative threshold value. At some time, an understeer state of the vehicle is detected, and a value obtained by adding a multiplication value of the coefficient and the steering angular velocity to the steering angle is less than zero, and a value obtained by subtracting the target yaw rate from the actual yaw rate is A vehicle driving support control device that detects an understeer state of the vehicle when a predetermined positive threshold value or more is reached.   The vehicle driving support control according to claim 1, wherein the avoidance steering intention determination unit determines an intention of the driver to avoid avoiding the obstacle according to a lap rate between the host vehicle and the obstacle. apparatus.   The yaw moment adding means generates the yaw moment based on the difference between the inner and outer wheels of the braking force of the vehicle according to at least the deviation between the actual yaw rate of the vehicle and the yaw rate calculated from the motion model, and the yaw rate deviation In the region where the absolute value of the yaw rate is lower than the set value, only the yaw moment is added to the vehicle, and in the region where the absolute value of the yaw rate deviation exceeds the set value, a deceleration is added in addition to the yaw moment. The vehicle driving support control device according to claim 1 or 2.   The lane departure prediction means predicts a predicted lane departure time until the vehicle moves to avoid the obstacle, and deviates outward from the destination lane, and the yaw moment addition means includes at least the lane The yaw moment is generated by the difference between the inner and outer wheels of the braking force of the vehicle according to the expected departure time. In the region where the expected lane departure time exceeds the set time, only the yaw moment is added to the vehicle, and the set time is set. The vehicle driving support control device according to any one of claims 1 to 3, wherein a deceleration is added to the yaw moment in a shorter region.

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