JP5199205B2 - Vehicle control device - Google Patents

Description

  The present invention detects an obstacle (including a preceding vehicle) around a vehicle (own vehicle), supports the avoidance of the vehicle's contact with the detected obstacle, and stabilizes the behavior of the vehicle. The present invention relates to a vehicle control device having a function to

  Conventionally, by using a plurality of ultrasonic sensors arranged in an arc along the front bumper of the own vehicle and cameras arranged on the left and right sides of the own vehicle, obstacle data in front of the vehicle and obstacles on the side of the vehicle are used. A vehicle control device has been proposed that detects an area in which the vehicle can proceed by avoiding contact with the obstacle, that is, a contact avoidance area, from these data (Patent Document 1).

  Patent Document 2 discloses a vehicle control device (vehicle posture stabilization device) that stabilizes the behavior of a vehicle based on a yaw rate deviation calculated by comparing a reference yaw rate (also referred to as a reference yaw rate) and an actual yaw rate. Has been proposed.

JP 2008-49959 A (paragraph [0019]) JP 2007-276564 A (paragraph [0008])

  In the technique according to Patent Document 1, when the detected contact avoidance area is on the right side of the traveling direction of the host vehicle, the steering handle is operated to the right to avoid contact with the obstacle, When the contact avoidance area is on the left side of the traveling direction of the host vehicle, the traveling handle is operated to the left to avoid contact with an obstacle.

  In this case, the appropriate timing to start turning the steering wheel differs depending on whether the distance to the contact avoidance area is short or far. For this reason, an appropriate timing is set according to the distance to the contact avoidance area, and at the set timing, a warning means such as a lamp, chime, buzzer, speaker, etc. is used to avoid contact with the obstacle to the driver Outputs an alarm prompting spontaneous steering operation.

  In the above-mentioned Patent Document 2, as vehicle motion control, when oversteer or understeer occurs in a turning state, the brake on the turning outer wheel side or the inner wheel side is actuated so that the steering characteristic becomes neutral. A vehicle attitude stabilization support system for improving stability, a technology related to a so-called VSA (Vehicle Stability Assistant) system, and a motor for generating an assist steering force in a steering transmission mechanism that transmits a steering force of a steering handle to a wheel A technique related to a steering control system that adjusts the assist steering force of a motor so that the steering characteristic of an electric power steering apparatus provided with a motor is neutral is disclosed.

  By the way, the vehicle posture stabilization control function according to the vehicle posture stabilization support system can switch the on / off state of the function when the driver turns on / off the vehicle posture stabilization control function on / off switch or the like. ing. In some cases, the vehicle posture stabilization control function cannot be executed due to a failure, and the vehicle posture is substantially off.

  Timing for performing the contact avoidance support control function related to generation of an alarm or the like when the vehicle posture stabilization control function is on, and an alarm when the vehicle posture stabilization control function is off Nothing is disclosed in Patent Documents 1 and 2 regarding the relationship with the timing of performing the contact support control function related to the occurrence of the above.

  The present invention has been made in consideration of such problems, and provides a vehicle control device that can accurately perform the contact avoidance support control function regardless of whether the vehicle attitude stabilization control function is on or off. With the goal.

  The vehicle control device according to the present invention includes obstacle detection means for detecting obstacles around the vehicle, vehicle posture stabilization means for stabilizing the behavior of the vehicle by controlling braking force of wheels of the vehicle, Contact avoidance support means for performing a contact avoidance support control function of the vehicle for the obstacle detected by the obstacle detection means, and includes the following features 1 to 5.

  1. When the vehicle posture stabilization control function by the vehicle posture stabilization unit is turned off, and when the vehicle posture stabilization control function by the vehicle posture stabilization unit is turned on, the contact avoidance support unit The contact avoidance support control function is performed at a timing earlier than the above timing.

  According to the invention having the feature 1, when the vehicle posture stabilization control function by the vehicle posture stabilization means is in the off state, the contact avoidance support control function is performed at an earlier timing than when the vehicle posture stabilization control function is in the on state. As a result, even when the vehicle posture stabilization control function is in the OFF state, it is possible to accurately perform contact avoidance support. As a result, the contact avoidance support control function, the vehicle posture stabilization control function, Accurate coordinated control can be performed.

  2. In the invention having the above-described feature 1, the contact avoidance support unit includes an alarm generation unit, and the alarm generation unit avoids contact with the obstacle detected by the obstacle detection unit. It is preferable to generate an alarm prompting the contact avoidance operation.

  3. In the invention having the above feature 2, it is preferable that the alarm generation means delays the alarm generation timing as the vehicle speed of the vehicle decreases.

  4). In the invention having any one of the above characteristics 1 to 3, it is preferable that the contact avoidance support means has an automatic brake control means for performing automatic brake control.

  5). In the invention having any one of the above characteristics 1 to 4, the contact avoidance support means includes steering assist control means for assisting control of steering of the vehicle in a direction to avoid contact with the obstacle. It is preferable that

  According to the present invention, when the vehicle posture stabilization control function by the vehicle posture stabilization means is in the off state, the contact avoidance support control function is performed at an earlier timing than when the vehicle posture stabilization control function is in the on state. Even when the vehicle posture stabilization control function is in the OFF state, the contact avoidance support control function can be performed accurately. As a result, the contact avoidance support control function and the vehicle posture stabilization control function can be accurately performed. Coordinated control can be performed.

1 is a schematic block configuration diagram of a vehicle in which a vehicle control device according to an embodiment of the present invention is incorporated. It is relative position explanatory drawing, such as a lateral distance detected by a radar. It is a flowchart with which description of the contact avoidance assistance control operation | movement of a vehicle etc. with which the vehicle control apparatus was integrated is provided. It is explanatory drawing, such as a contact avoidance assistance control operation | movement of the vehicle incorporating a vehicle control apparatus.

  Embodiments of the present invention will be described below with reference to the drawings.

  FIG. 1 is a schematic block configuration diagram of a vehicle 10 (also referred to as a host vehicle) in which a vehicle control device according to an embodiment of the present invention is incorporated.

  The vehicle 10 includes an ECU (electronic control unit) 20 (functions as a vehicle control unit or the like) having various functional units (various functional units) realized by a CPU executing a program stored in a memory. The ECU 20 includes a VSA control unit 94 (vehicle posture stabilization unit, vehicle posture stabilization unit) and a contact avoidance support control unit 100 (contact avoidance support unit) as functional units.

  The VSA control unit 94 includes a reference yaw rate calculation unit 96 and a VSA function on / off state confirmation unit 98 (vehicle stabilization control function on / off state confirmation unit, vehicle stabilization control function on / off state confirmation unit).

  The VSA function on / off state confirmation unit 98 confirms the switching position (on state position or off state position) of the VSA on / off switch 83 and whether or not various sensors and actuators necessary for the VSA control are out of order. The function is in an on-state (state that is not faulty at the on-state position), or is in an off-state (off-state position or on-state) where the VSA control function is not selected or is faulty It is determined whether it is in a fault state even at the position.

  The contact avoidance assist control unit 100 includes a steering assist control unit 90 (steering assist control unit) and an automatic brake control unit 92 (automatic brake control unit).

  The vehicle 10 has four wheels 22 {front wheel right wheel (FRW) 22R, front wheel left wheel (FLW) 22L}, wheel 24 {rear wheel right wheel (RRW) 24R, rear wheel left wheel (RLW) 24L}, Wheel speed sensors 61 to 64 are respectively attached to the four wheels 22 and 24, and the wheel speeds Vw are taken into the ECU 20 from the wheel speed sensors 61 to 64. The ECU 20 constantly updates the average value of these four wheel speeds Vw as the vehicle speed Vs that is the speed of the vehicle 10.

  The four wheels 22 and 24 are provided with brake actuators 51 to 54 each constituted by a disc brake or the like that generates a braking force. Each braking force (braking hydraulic pressure) of the brake actuators 51 to 54 is independently controlled by four pressure regulators (not shown) in the hydraulic control device 44.

  The hydraulic control device 44 generates a braking hydraulic pressure corresponding to the depression amount θb of the brake pedal 40 detected by the depression amount sensor 42 and does not depend on the brake pedal 40 output from the automatic brake control unit 92 constituting the ECU 20. The four pressure regulators (not shown) generate braking hydraulic pressures according to the braking force command value Fb (so-called braking force command value by so-called brake-by-wire), and output it to the brake actuators 51 to 54. .

  When the depression amount θb is input from the depression amount sensor 42 and the braking force command value Fb is input from the automatic brake control unit 92 based on the depression operation of the brake pedal 40 by the driver, the hydraulic control device 44 The brake hydraulic pressure is generated in accordance with whichever is greater.

  Therefore, when the vehicle 10 turns {including, for example, any case where the vehicle 10 slips and steers, or is steered (steered) by operating the steering handle 70. }, If the braking hydraulic pressure transmitted to the brake actuators 51 to 54 is independently controlled by the braking force command value Fb, a difference is generated between the braking forces of the left and right wheels 22L, 24L, 22R, 24R, and the yaw moment of the vehicle 10 is increased. Can be controlled arbitrarily and accurately, avoiding the occurrence of understeering at the time of turning, and avoiding oversteering and spins, thereby stabilizing the behavior of the vehicle. Further, if the braking hydraulic pressure transmitted to each of the brake actuators 51 to 54 is controlled independently during braking (automatic braking when the brake pedal 40 is not depressed or when the brake pedal 40 is depressed), the wheels 22, 24 are controlled. Anti-lock brake control can be performed to suppress the lock.

  On the other hand, the driving force is transmitted from the engine 34 through the transmission (T / M) 36 to the front wheels 22 (22R, 22L) among the four wheels 22, 24. The rear wheels 24 (24R, 24L) function as driven wheels that rotate as the vehicle 10 travels.

  The engine 34 has its rotational speed (engine rotational speed) controlled through a throttle actuator 32 that adjusts the throttle opening of a throttle valve 33 provided in the engine 34.

  The throttle opening of the throttle valve 33 is adjusted through the engine ECU 30 and the throttle actuator 32 according to the operation angle (accelerator angle, operation amount) θa of the accelerator pedal 26 detected by the operation amount sensor 28.

  The steering device 88 of the vehicle 10 basically includes a steering handle 70 (steering wheel) that is rotated (steered) by a driver, a steering angle sensor 72 that detects a steering angle θs of the steering handle 70, A steering actuator 76 constituting an electric power steering device (EPS device) and a steering mechanism 74 having a rack and pinion mechanism for steering the front wheels 22 (front left and right wheels) are configured.

  In this case, in the steering device 88, the rotation operation of the steering handle 70 by the driver is transmitted to the pinion constituting the steering mechanism 74 through the steering shaft and the connecting shaft, and the rack reciprocates due to the rotation of the pinion. The movement is transmitted to the front wheels 22 through the tie rods, so that the vehicle 10 is steered.

  When the steering of the vehicle 10 is executed, the steering angle θs associated with the rotation operation of the steering handle 70 by the driver is input to the steering actuator 76, so that the driving force of the steering actuator 76, that is, steering is performed. A steering assist force depending on the operation of the handle 70 is transmitted to the front wheels 22 through the rack of the steering mechanism 74.

  On the other hand, a steering assist command value Fs (herein, a steering assist command value by steer-by-wire, also referred to as an avoidance steering assist command value Fs) output from a steering assist control unit 90 constituting the ECU 20 is input to the steering actuator 76. Thus, a steering assist torque (steer torque) corresponding to the steering assist command value Fs is output to the steering mechanism 74. Note that the steering assist is not limited to processing by steer-by-wire, and may be processing for changing the gear ratio of the steering mechanism 74 or processing for changing the assist value of the EPS device.

  The steering mechanism 74 outputs a steering assist force corresponding to the steering assist torque corresponding to the steering assist command value Fs to the front wheels 22, so that the front wheels 22 steer the front wheels 22 by a steering amount corresponding to the steering assist force. Can be made.

  The steering assist command value Fs is basically determined that avoidance steering is not sufficient due to the rotation operation of the steering handle 70 by the driver when trying to avoid contact with an obstacle ahead of the vehicle 10. When it happens, it occurs to assist this.

  Note that when the avoidance steering assist force is generated, when the steering assist command value Fs is output to the steering actuator 76, the braking force that does not depend on the brake pedal 40 from the VSA control unit 94 and the automatic brake control unit 92 together or independently. The command value Fb is output to the hydraulic control device 44 and the braking hydraulic pressure transmitted to the brake actuators 51 to 54 is independently controlled, and a difference is generated between the braking forces of the left and right wheels 22L, 24L, 22R, 24R. The avoidance steering assist force may be generated by generating a yaw moment.

  The vehicle 10 further includes a yaw rate sensor 82 that detects a yaw rate Yr generated in the vehicle 10 (rotational force about the central axis when the vehicle 10 is viewed from directly above), and a lateral force generated in the vehicle 10. A lateral G sensor 84 for detecting G (lateral acceleration) is provided.

  Furthermore, the vehicle 10 is provided with an alarm device 86 that generates an alarm, and generates an alarm that prompts the driver to depress the brake pedal 40 (brake operation) or to rotate the steering handle 70 (steering operation). . The alarm for the driver is generated using alarm means such as a lamp, chime, buzzer, speaker, etc. of the alarm device 86. Although an alarm may be generated by the alarm device 86, a reaction force is applied to the steering handle 70 and a reaction force is applied to the accelerator pedal 26 with or without an alarm from the alarm device 86. An alarm can also be generated by applying or applying a reaction force to the brake pedal 40.

  Further, the vehicle 10 is provided with a radar 80 in a front grill portion or the like. The radar 80 transmits an electromagnetic wave such as a millimeter wave toward the front of the vehicle 10 as a transmission wave, detects the size of an obstacle (for example, a preceding vehicle, etc.) based on the reflected wave, and the obstacle vehicle. The direction from 10 (own vehicle) is detected, and at the same time, the relative distance L between the obstacle and the own vehicle (inter-vehicle distance if the obstacle is a vehicle), the relative speed Vr between the obstacle and the own vehicle. It operates as a relative position detecting means for detecting the like. Note that a laser radar, a stereo camera, or the like can be employed instead of the millimeter wave radar as a relative position detecting means for detecting a relative position with respect to an obstacle.

  The contents such as the relative position detected by the radar 80 will be described with reference to FIG.

  As is well known, the radar 80 can first detect the relative distance L from the vehicle 10 (the vehicle is depicted in two places at different positions in FIG. 2) to the vehicle 12 ahead. . Further, the vehicle width Wo of the vehicle 12 ahead can be detected. Note that the vehicle width Wm of the host vehicle 10 is stored in advance in a memory (storage unit) in the ECU 20 and the radar 80. Next, the relative speed Vr of the vehicle 10 with respect to the vehicle 12 can be detected. Furthermore, a contact margin time TTC (Time To Contact) as a contact margin value can be calculated as TTC = L / Vr from the relative distance L from the vehicle 10 to the vehicle 12 ahead and the relative speed Vr.

  The contact margin value is a parameter for determining the possibility of contact between an obstacle (here, the vehicle 12) in front of the host vehicle (vehicle 10) and the host vehicle. On the contrary, the smaller the contact margin value, the higher the possibility of contact. The contact margin value includes the contact margin time TTC and the relative distance L to the obstacle.

The ECU 20 determines, for example, the vehicle 10 (own vehicle) from the vehicle width Wm of the vehicle 10 (own vehicle) itself, the vehicle width Wo of the vehicle 12 in front detected by the radar 80, and a predetermined margin width α (margin lateral distance). The target lateral avoidance distance Dt required when the vehicle is overtaking while avoiding contact with the vehicle 12 ahead is calculated by the following equation (1).
Dt = (Wo / 2) + α + (Wm / 2) (1)

  The lateral avoidance distance (referred to as lateral distance, offset or offset amount) D increases because the vehicle 10 (own vehicle) avoids contact with the preceding vehicle 12 and overtakes it on the own vehicle center axis 10c. This is a case where the other vehicle center axis 12c of the front vehicle 12 overlaps, that is, a case where the front vehicle 12 exists in front of the vehicle 10 (own vehicle).

  Even when the vehicle 12 ahead is present in front of the vehicle 10 (own vehicle), when the vehicle 10 catches up with another vehicle 12 traveling on the same route on the road 200, the vehicle 10 If the vehicle 10 moves in the vehicle width direction (lateral direction) by the above-mentioned target lateral avoidance distance Dt when passing the side of the vehicle 12 ahead of the vehicle by changing the course and exiting ahead of the vehicle 12, It is possible to pass through the side of the vehicle 12 ahead, leaving a lateral distance corresponding to the margin width α. In addition, the distance (deviation) in the vehicle width direction between the own vehicle center axis 10c and the other vehicle center axis 12c of the vehicle 12 ahead is referred to as an offset D as described above.

  The vehicle 10 incorporating the vehicle control apparatus according to the embodiment of the present invention is basically configured as described above. Next, the operation of the vehicle 10 by the VSA control unit 94 will be described first. Examples of operating conditions of the posture stabilization control function will be described, second, examples of operating conditions of contact avoidance automatic brake control by the automatic brake control unit 92 will be described, and third, contact avoidance by the steering assist control unit 90 will be described An example of operating conditions of steering assist control (avoidance steering assist control) will be described, and fourthly, an example of operating conditions of the alarm device 86 will be described.

  First, the VSA control unit 94 is configured to operate when the vehicle 10 is in a turning state and there is a certain difference between the reference yaw rate Ys and the actual yaw rate Yr.

  When the vehicle 10 turns, the VSA control unit 94 calculates a reference yaw rate Ys indicating how much the driver is going to turn from the steering angle θs and the vehicle speed Vs by the reference yaw rate calculation unit 96 based on the vehicle motion model and the like. To do. The reference yaw rate Ys is set as a target value and compared with the actual yaw rate Yr detected by the yaw rate sensor 82 in real time.

  When the actual yaw rate Yr is larger than the reference yaw rate Ys (Yr> Ys), it is determined that there is a possibility of oversteering, in other words, there is a possibility that the vehicle will spin too much due to a sudden handle or the like. Automatic braking is applied to the inner and outer wheels to generate outward force. For example, when turning left, the front wheel right wheel 22R is braked via the brake actuator 51 through the automatic brake control unit 92 to generate a force in the right turning direction.

  On the other hand, if the actual yaw rate Yr is smaller than the reference yaw rate Ys (Yr <Ys), it may be understeered. In addition, the throttle opening of the throttle valve 33 is reduced through the throttle actuator 32 to suppress the engine output, and an inward force for bending the vehicle 10 is generated by braking the inner wheel in the rear wheel 24 as necessary. For example, when turning left, the rear left wheel 24L is braked via the brake actuator 51 through the automatic brake control unit 92 to generate a force in the left turning direction.

  As described above, if the braking hydraulic pressure transmitted to the brake actuators 51 to 54 when the vehicle 10 turns is controlled independently under the control of the VSA control unit 94, the difference between the braking forces of the left and right wheels 22L, 24L, 22R, 24R. And the yaw moment of the vehicle 10 is arbitrarily controlled to avoid the occurrence of understeer during turning and the occurrence of oversteer and spin, thereby stabilizing the behavior of the vehicle.

  Secondly, the operation of the automatic brake control by the automatic brake control unit 92 is determined based on a contact margin time TTC (TTC = L / Vr) as a contact margin value for an obstacle ahead of the vehicle 10. You may judge based on the relative distance L with the obstacle (a front vehicle is also included) ahead of the vehicle 10. FIG.

  In this case, the threshold of the contact allowance time TTC is, for example, a fixed time (1 [s] to 3 [when the vehicle posture stabilization control function by the VSA control unit 94 is on, regardless of the vehicle speed Vs. s] is a threshold Tth at which the automatic brake control and / or avoidance steering assist control is activated. The threshold of the relative distance L is a smaller distance (shorter distance) as the vehicle speed Vs is smaller. 70 [m] to around 30 [m]). Of course, the threshold value Tth of the contact allowance time TTC may be changed according to the vehicle speed Vs, the steering state of the steering handle 70 by the driver, or the like.

  Specifically, the automatic brake control unit 92 calculates a braking force command value Fb that gives an appropriate braking force to the brake actuators 51 to 54 and outputs the braking force command value Fb to the hydraulic control device 44 in order to generate the necessary deceleration. . As a result, a braking hydraulic pressure corresponding to the braking force command value Fb is generated by the hydraulic control device 44, and the braking force is applied to the wheels 22 and 24 through the brake actuators 51 to 54 by the generated braking hydraulic pressure.

  When the automatic brake control unit 92 determines that the accelerator pedal 26 is depressed from the operation amount θa of the accelerator pedal 26, the automatic brake control unit 92 simultaneously controls the throttle actuator 32 and operates the throttle valve 33 in the closing direction by a predetermined amount. (Throttle-by-wire) may be used (see the dotted arrow line from the ECU 20 to the throttle actuator 32 in FIG. 1).

  Third, in addition to the contact allowance time TTC, the steering assist control unit 90 determines from the midpoint (steering angle θ when the vehicle 10 is considered to travel linearly for a predetermined time) obtained from the steering angle sensor 72. The steering angle θs, the steering angular velocity dθs / dt obtained by time differentiation of the steering angle θs, the lateral G detected by the lateral G sensor 84, and the yaw rate (actual yaw rate) Yr detected by the yaw rate sensor 82 are determined. . That is, SE = SE (θs, dθs / dt) in which the driver's avoidance steering operation state determination value SE is a predetermined function with the steering angle θs, the steering angular velocity dθs / dt, the lateral G, the yaw rate Yr, and the like as variables. , Lateral G, Yr) (assuming that the greater the SE, the greater the avoidance steering operation is determined by the driver). When it is determined that the necessary value (threshold value SEth) or a value lower than the necessary value (threshold value SEth), avoidance steering assist control is activated.

  When the avoidance steering assist control is activated, the reference yaw rate Ys calculated according to the steering angle θs and the vehicle speed Vs is changed to the assist yaw rate Ya.

  When calculating the assist yaw rate Ya, the difference between the above-described target lateral avoidance distance Dt and the lateral distance D (the amount of deviation between the vehicle center axis 10c and the other vehicle center axis 12c) is multiplied by a predetermined gain to assist. Calculate the lateral acceleration. Further, the assist yaw rate Ya is calculated by dividing the assist lateral acceleration by the vehicle speed Vs.

  The steering assist control unit 90 outputs a steering assist command value Fs for generating the calculated assist yaw rate Ya to the steering actuator 76.

  Accordingly, a steering assist torque corresponding to the steering assist command value Fs is applied from the steering actuator 76 to the steering mechanism 74, whereby the turning behavior of the vehicle 10 is controlled and assisted by the assist yaw rate Ya.

  In the avoidance steering assist control, the steering mechanism 74 is controlled to assist the steering, and as described above, the VSA control unit 94 and the automatic brake control unit 92 are controlled together to generate the yaw moment in the vehicle 10. You may make it assist.

  As described above, an example of the operation condition of the vehicle posture stabilization control by the VSA control unit 94, an example of the operation condition of the contact avoidance automatic brake control by the automatic brake control unit 92, and the contact avoidance steering assist control by the steering assist control unit 90 ( Although an example of the operation condition of (steering assist control) has been described, the steering assist control unit 90 performs steering by controlling the steering angle of the front wheels 22 that are the steering wheels through the steering actuator 76 and the steering mechanism 74, whereas When the steering angle is controlled, the VSA control unit 94 controls the spin caused by oversteer and the bulge caused by understeer by generating a yaw moment in the reverse direction. As a result, the steering and brake are controlled. The automatic brake control unit 92, the steering assist control unit 90, and the VSA control unit 94 are the same. In some cases to operate in.

  Fourth, as will be described in detail later, the alarm generation timing of the alarm device 86 is determined by the threshold value Tth + βt when the vehicle 10 adds the margin βt (time) to the threshold value Tth of the contact margin time TTC {or relative distance L It is assumed that the vehicle approaches the obstacle such as the vehicle 12 up to the threshold value Lth + position of βd (distance) added to the threshold value Lth. In other words, the alarm is set to be generated at a timing before the automatic brake control and the avoidance steering assist control are activated.

  The alarm generation timing of the alarm device 86 is such that when the vehicle posture stabilization control function by the VSA control unit 94 is in the off state (when VSA = OFF), the vehicle posture stabilization function is in the on state (when VSA = ON). ) Is controlled so as to generate an alarm at a timing earlier than the operation start timing.

  Next, refer to the flowchart of FIG. 3 and the operation schematic diagram of FIG. 4 for cooperative control of the contact avoidance support control function and the vehicle stabilization control function of the vehicle 10 in which the vehicle control apparatus according to one embodiment of the present invention is incorporated. To explain. In the following description, turning on the control flag is different from operating (executing) the control. Control will not operate unless the control flag is on.

  In step S1, the vehicle 10 traveling on the road 200 confirms whether or not the vehicle posture stabilization control function is turned off by the VSA function on / off state confirmation unit 98 based on the on / off state of the VSA on / off switch 83 or the like. To do.

  If the VSA function is not turned off, that is, if the VSA function is turned on (when VSA = ON), the determination in step S1 is negative, and in step S2, the timing control of alarm generation at the normal timing is performed. Is set to a threshold value Tth + βt1 [time] (or Lth + βd1 [distance]).

  On the other hand, if it is in the off state (when VSA = OFF), the determination in step S1 is affirmative, and in step S3, the threshold value Tth + βt2 (corresponding to the timing control of alarm generation at a timing earlier than the normal timing) Or Lth + βd2) is set (βt1 <βt2, βd1 <βd2). Note that, as the vehicle speed Vs of the vehicle 10 is smaller, the alarm generation frequency can be suppressed when the vehicle 10 is traveling at a low speed by delaying the alarm generation timing.

  Next, in step S4, the vehicle 10 traveling on the road 200 uses the radar 80 to detect the relative position (relative distance L, vehicle width Wo, relative speed Vr, contact margin) of the vehicle 12 ahead of the vehicle 10 (own vehicle). Time TTC) is detected. At this time, the ECU 20 calculates a target lateral avoidance distance Dt. The relative position detection process is always performed by timer interruption in the ms order.

  Next, in step S5, it is determined whether or not the contact margin time TTC detected in step S4 is smaller than the threshold value Tth + βt2.

  As shown between time points t0 and t1 in FIG. 4, when the contact margin time TTC is greater than the threshold value Tth + βt2, the determination in step S5 is negative, and in step S6, the automatic brake control flag fb and the steering assist flag are determined. Both fs are turned off (fb → OFF, fs → OFF).

  On the other hand, when the contact margin time TTC is smaller than the threshold value Tth + βt2, as shown in the positional relationship between the vehicle 10 and the vehicle 12 such as between the time points t1 and t2 in FIG. Both the automatic brake control flag fb and the steering assist flag fs are turned on (fb → ON, fs → ON).

  Next, in step S8, when VSA = ON, an alarm is generated through the alarm device 86 at time t2 (TTC = Tth + βt1) in FIG. 4 to prompt the driver to operate the brake pedal 40 or the steering handle 70. . In step S8, when VSA = OFF, the alarm is generated through the alarm device 86 at time t1 (TTC = Tth + βt2), which is earlier than time t2.

  If it is determined in the next step S9 that the contact allowance time TTC is not smaller than the threshold value Tth (TTC ≧ Tth), the processes after step S1 are repeated.

  On the other hand, when the determination in step S9 becomes affirmative, that is, as shown at time t2b as an example, the contact allowance time TTC for the vehicle 12 positioned in front of the vehicle 10 (own vehicle) becomes smaller than the threshold Tth. If the distance L between the vehicle 12 and the preceding vehicle 12 is smaller than the threshold value Lth, it is detected in step S10 whether or not there is avoidance steering by the steering handle 70 by the driver. If the operation of the handle 70 is not detected, the automatic brake control is immediately activated at the time t2 in step S11.

  On the other hand, in step S10, when avoidance steering by the steering handle 70 by the driver is detected by a change in the steering angle θs from the steering angle sensor 72 under the condition of TTC <Tth, in step S12, When the avoidance steering situation determination value SE for evaluating the avoidance operation by the steering handle 70 is determined to be equal to or less than a threshold value SEth that requires avoidance steering assist control, and SE ≦ SEth, In step S13, the avoidance steering assist control is immediately activated.

  As described above, according to the above-described embodiment, the radar 80 serving as the obstacle detection unit detects the vehicle 12 or the like that is an obstacle around the vehicle 10, and the contact avoidance support control unit 100 detects the radar 80. The avoidance of contact between the vehicle 12 and the like and the vehicle 10 is supported.

  Then, the contact avoidance support control unit 100 is more in the on state (when VSA = ON) when the vehicle posture stabilization control function by the VSA control unit 94 is in the off state (when VSA = OFF). An alarm is generated at an early timing.

  Thus, when the control function by the VSA control unit 94 is in the OFF state (when VSA = OFF), contact avoidance support control by the contact avoidance support control unit 100 at an earlier timing, for example, a steering handle by an alarm Since the driver is prompted to perform the operation 70, the contact avoidance support control function can be performed accurately, and as a result, the accurate cooperation control of the contact avoidance support control function and the vehicle attitude stabilization control function is performed. be able to.

  More specifically, when the VSA control unit 94 is in an off state (including when it is out of control and cannot be controlled), if the obstacle avoidance operation is delayed, the vehicle behavior may become unstable. Therefore, in other words, since the contact avoidance support control function is performed from a farther point, the avoidance action can be surely performed.

  Note that the present invention is not limited to the above-described embodiment, and it is needless to say that various configurations can be adopted based on the contents described in this specification.

DESCRIPTION OF SYMBOLS 10 ... Vehicle 22, 24 ... Wheel 20 ... ECU 80 ... Radar 90 ... Steering assist control part 92 ... Automatic brake control part 94 ... VSA control part 96 ... Reference yaw rate calculation part 98 ... VSA function on / off state confirmation part 100 ... Contact avoidance support Control unit

Claims (5)

Obstacle detection means for detecting obstacles around the vehicle;
Vehicle posture stabilization means for stabilizing the behavior of the vehicle by controlling the braking force of the wheels of the vehicle;
Contact avoidance support means for performing a contact avoidance support control function of the vehicle with respect to the obstacle detected by the obstacle detection means;
With
The contact avoidance support means has a timing earlier than a timing when the vehicle attitude stabilization control function is on when the vehicle attitude stabilization control function by the vehicle attitude stabilization means is off. The vehicle control device performs the contact avoidance support control function. The vehicle control device according to claim 1,
The contact avoidance support means has an alarm generation means, and the alarm generation means generates an alarm for prompting a contact avoidance operation for avoiding contact with the obstacle detected by the obstacle detection means. A vehicle control device. The vehicle control device according to claim 2,
The alarm generation means delays the alarm generation timing as the vehicle speed of the vehicle decreases. In the vehicle control device according to any one of claims 1 to 3,
The contact avoidance support means includes
A vehicle control device comprising an automatic brake control means for performing automatic brake control. In the vehicle control device according to any one of claims 1 to 4,
The contact avoidance support means includes
A vehicle control device comprising steering assist control means for assisting the steering of the vehicle in a direction to avoid contact with the obstacle.

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