JP6060112B2 - Vehicle control device - Google Patents

Description

  The present invention relates to a vehicle control device including an automatic brake control unit that performs automatic brake control that automatically generates braking force on wheels without depending on a brake operation in the event of a vehicle collision.

  For example, Patent Document 1 describes a technical idea in which a predetermined braking force that is set in advance is automatically generated on a wheel when the airbag is deployed due to a vehicle collision to stop the vehicle.

JP 2012-001091 A

  By the way, when the vehicle collides on the downhill, the vehicle is accelerated by gravity, and when the vehicle collides on the uphill, the vehicle is decelerated by the gravity. However, in the conventional technique such as Patent Document 1 described above, a constant braking force is generated on the wheels regardless of whether the vehicle is located on a downhill or an uphill at the time of a vehicle collision.

  Therefore, for example, if the braking force is set to be relatively small, the vehicle may not be efficiently decelerated when the vehicle collides on a downhill. On the other hand, if the braking force is set to be relatively large, an occupant may receive an excessive load from the seat belt when the vehicle collides on an uphill.

  The present invention has been made in consideration of such a problem. When a vehicle collides on a downhill, the vehicle can be efficiently decelerated after the vehicle collision, and when the vehicle collides on an uphill, An object of the present invention is to provide a vehicle control device capable of suppressing a load received from a seat belt.

  A vehicle control apparatus according to the present invention includes an inclination detection unit that detects an inclination of a road surface on which a vehicle is located at the time of a vehicle collision, and an automatic brake control that automatically generates a braking force on wheels without depending on a brake operation at the time of the vehicle collision. The automatic brake control unit includes a braking force of the wheel when the vehicle is located on a downhill at the time of a vehicle collision, and the vehicle is located on an uphill at the time of a vehicle collision. In this case, the braking force is larger than the braking force of the wheel.

  According to the vehicle control device of the present invention, when the vehicle collides on a downhill, a relatively large braking force is generated on the wheels, so that the vehicle can be efficiently decelerated after the vehicle collision. In addition, when the vehicle collides on an uphill, a relatively small braking force is generated on the wheels, so that the load that the occupant receives from the seat belt can be suppressed.

  In the above vehicle control device, the automatic brake control unit may be configured such that the braking force of the wheel when the vehicle is rearwardly impacted on a downhill is greater than the braking force of the wheel when the vehicle is forwardly impacted on a downhill. It may be small.

  According to such a configuration, even when the vehicle is accelerated after the vehicle is collided after being impacted rearward on a downhill, the braking force of the wheels at this time is relatively small, so that the occupant can The load received from the belt can be suppressed.

  In the above vehicle control device, the automatic brake control unit continues to generate braking force on the wheels until a predetermined braking continuation time has elapsed since the vehicle stopped after a vehicle collision, and the vehicle was rearwardly bumped on a downhill. In this case, the braking duration time may be longer than the braking duration time when the vehicle is bumped uphill.

  According to such a configuration, it is possible to effectively avoid the movement of the vehicle due to the creep phenomenon after the vehicle has stopped after a rear impact on a downhill.

  ADVANTAGE OF THE INVENTION According to this invention, when a vehicle collides on a downhill, a vehicle can be decelerated efficiently after a vehicle collision, and the load which a passenger | crew receives from a seatbelt when a vehicle collides on an uphill can be suppressed.

It is a block diagram of the vehicle provided with the vehicle control apparatus which concerns on one Embodiment of this invention. It is a 1st flowchart explaining the automatic brake control by the vehicle control apparatus shown in FIG. FIG. 4 is a second flowchart illustrating automatic brake control by the vehicle control device shown in FIG. 1.

  DESCRIPTION OF EMBODIMENTS Hereinafter, a vehicle control apparatus according to the present invention will be described with reference to the accompanying drawings by giving preferred embodiments in relation to a vehicle equipped with the same.

  The vehicle 12 is configured as a four-wheel vehicle having a pair of left and right front wheels and a pair of left and right rear wheels. As shown in FIG. 1, the vehicle control device 10 performs various controls including automatic brake control of each wheel 14. It has.

  The vehicle control device 10 controls the brake pressure (braking hydraulic pressure) provided corresponding to the four brake parts 16 constituted by disc brakes and the like for generating a braking force on each wheel 14 and the brake parts 16. And a general control unit 20.

  The brake actuator 18 generates a brake pressure having a magnitude corresponding to the amount of operation of the brake pedal 34. The brake actuator 18 generates a brake pressure having a magnitude corresponding to the automatic brake control signal output from the overall control unit 20 without depending on the operation (brake operation) of the brake pedal 34.

  The overall control unit 20 includes various sensors such as a vehicle speed detection unit (vehicle speed detection unit) 22, a collision detection sensor 24, a tilt detection unit (tilt detection unit) 26, an accelerator pedal operation amount sensor 28, and a brake pedal operation amount sensor 30. It is connected.

  The vehicle speed detection part 22 can use the wheel speed sensor provided in each wheel 14, for example. In this case, the average value of the wheel speeds detected by the four wheel speed sensors is detected as the vehicle speed. The collision detection sensor 24 detects a vehicle collision, and is provided in a pair of left and right frontal collision detection sensors provided in the front frame, a pair of left and right side collision detection sensors provided in the center frame, and a rear frame. And a pair of left and right rear collision detection sensors. However, the number or location of the collision detection sensor 24 can be arbitrarily set. For example, an acceleration sensor (G sensor) can be used as the collision detection sensor 24.

  The inclination detection unit 26 detects the inclination (inclination state) of the road surface on which the vehicle 12 is located. For example, the inclination detection unit 26 is disposed in front of and behind the vehicle and detects an inclination angle in the front-rear direction of the vehicle 12, or A navigation device or the like can be used. The accelerator pedal operation amount sensor 28 detects the operation amount of the accelerator pedal 32, and the brake pedal operation amount sensor 30 detects the operation amount of the brake pedal 34.

  The overall control unit 20 includes an ECU (Electronic Control Unit). As is well known, the ECU is a computer including a microcomputer, and includes a memory 36 such as a CPU (Central Processing Unit), a ROM (Read Only Memory), and a RAM (Random Access Memory), an A / D converter, and a D / A. An input device such as a converter and a timer (timer) 38 as a clock unit are provided. The ECU functions as various function realization units (function realization means), for example, a control unit, a calculation unit, a processing unit, and the like when the CPU reads and executes a program recorded in the ROM.

  The memory 36 stores a first braking duration time ta, a second braking duration time tb, a third braking duration time tc, and a fourth braking duration time td. The first to fourth braking continuation times ta to td are times during which braking force is continuously generated on each wheel 14 after the vehicle has stopped after a vehicle collision. In the present embodiment, the second braking duration time tb is set longer than the first braking duration time ta, and the fourth braking duration time td is set longer than the third braking duration time tc. Further, the first braking duration time ta is set longer than the third braking duration time tc, and the second braking duration time tb is set longer than the fourth braking duration time td. However, the first to fourth braking durations ta to td can be arbitrarily set. The timer 38 measures the elapsed time after stopping after a vehicle collision.

  The overall control unit 20 is provided with an acceleration sensor (not shown) such as an orthogonal three-axis G sensor, a roll rate sensor, and a yaw rate sensor. These sensors can sense the posture and behavior of the host vehicle 12.

  The overall control unit 20 includes a collision determination unit 40, a ramp determination unit 42, a time determination unit 44, and an automatic brake control unit 46.

  The collision determination unit 40 determines whether there is a vehicle collision based on the output signal from the collision detection sensor 24. Specifically, the collision determination unit 40 determines the presence or absence of a vehicle collision by comparing the output signal of the collision detection sensor 24 with the output signal of the orthogonal three-axis G sensor, and the collision mode (front collision, side collision). , Rear collision).

  The ramp determination unit 42 determines whether the host vehicle 12 is located on an uphill or a downhill at the time of a vehicle collision based on an output signal from the tilt detection unit 26. The time determination unit 44 determines whether or not the measurement time t of the timer 38 has passed the first to fourth braking durations ta to td.

  The automatic brake control unit 46 outputs a brake control signal (automatic brake control signal) to the brake actuator 18 at the time of a vehicle collision, so that a predetermined braking force is applied to the wheels 14 without depending on the operation of the brake pedal 34 by the driver. Performs automatic brake control that occurs automatically.

  The vehicle 12 including the vehicle control device 10 according to the present embodiment is basically configured as described above. Next, brake control by the vehicle control device 10 will be described.

  As shown in FIG. 2, first, the collision determination unit 40 determines the presence or absence of a vehicle collision based on the output signal of the collision detection sensor 24 (step S1). If the collision determination unit 40 determines that there is no vehicle collision (step S1: NO), the process of step S1 is repeated.

  If the collision determination unit 40 determines that a vehicle collision has occurred (step S1: YES), the ramp determination unit 42 determines whether the vehicle is located on an uphill or a downhill at the time of the vehicle collision. (Step S2).

  When the slope determination unit 42 determines that the vehicle is a downhill, the collision determination unit 40 determines whether the collision mode is a normal collision (frontal collision) or a rear collision (rear collision) ( Step S3). If the collision determination unit 40 determines that the collision is normal, the automatic brake control unit 46 performs the first automatic brake control (step S4).

  Specifically, the automatic brake control unit 46 outputs a first automatic brake control signal to the brake actuator 18. Then, the brake actuator 18 outputs a first brake pressure having a magnitude corresponding to the magnitude of the first automatic brake control signal to each brake unit 16, so that a first braking force is generated on each wheel 14. Accordingly, the vehicle 12 is automatically decelerated at the predetermined first deceleration without depending on the driver's operation of the brake pedal 34.

  When the vehicle collides normally on the downhill, the vehicle 12 is accelerated by gravity, and therefore, the vehicle 12 is likely to be at a higher speed than when the vehicle collides on the uphill. For this reason, the first braking force is set to be larger than a third braking force and a fourth braking force described later when the vehicle collides on an uphill. Thereby, the vehicle 12 can be decelerated efficiently when it hits normally on the downhill.

  Then, the overall control unit 20 determines whether or not the host vehicle 12 has stopped based on the output signal from the vehicle speed detection unit 22 (step S5). When the overall control unit 20 determines that the host vehicle 12 is not stopped (step S5: NO), the process returns to step S4, and the automatic brake control unit 46 continues the first automatic brake control.

  When it is determined by the overall control unit 20 that the host vehicle 12 has stopped (step S5: YES), the time determination unit 44 determines whether or not the measurement time t of the timer 38 has passed the first braking duration time ta. Is determined (step S6).

  When the time determination unit 44 determines that the measurement time t of the timer 38 has not passed the first braking duration time ta (step S6: NO), the process returns to step S4 and the automatic brake control unit 46 performs the first operation. Continue automatic brake control. Thereby, it is avoided that the vehicle 12 moves against the driver's intention immediately after stopping.

  When the time determination unit 44 determines that the measurement time t of the timer 38 has passed the first braking duration time ta (step S6: YES), the automatic brake control unit 46 stops the first automatic brake control. (Step S7). That is, the automatic brake control unit 46 stops the output of the first automatic brake control signal to the brake actuator 18 and releases the first braking force of each wheel 14. Thus, the driver can operate the vehicle 12 and retreat it to a safe place. At this stage, the current flowchart ends.

  In step S3, when it is determined by the collision determination unit 40 that there is a rear collision, the automatic brake control unit 46 performs the second automatic brake control (step S8).

  Specifically, the automatic brake control unit 46 outputs a second automatic brake control signal to the brake actuator 18. Then, the brake actuator 18 outputs a second brake pressure having a magnitude corresponding to the magnitude of the second automatic brake control signal to each brake unit 16, so that a second braking force is generated on each wheel 14. Here, since the second automatic brake control signal is smaller than the first automatic brake control signal, the second braking force is smaller than the first braking force. Accordingly, the vehicle 12 is decelerated at the second deceleration smaller than the first deceleration without depending on the driver's operation of the brake pedal 34.

  When the vehicle 12 is impacted on the downhill, the vehicle 12 is accelerated by gravity, so that the vehicle 12 is likely to be at a higher speed than when the vehicle collides on the uphill. For this reason, the second braking force is set to be larger than a third braking force and a fourth braking force described later when the vehicle collides on an uphill. Thereby, the vehicle 12 can be decelerated efficiently when it is made a rear-end collision.

  Further, when the vehicle crashes on the downhill, the vehicle 12 is accelerated by receiving the collision energy, and therefore, the vehicle 12 is likely to be at a higher speed than when the vehicle 12 collides normally on the downhill. Therefore, for example, if the second braking force in the case of a rearward impact on a downhill is made larger than the first braking force in the case of a forward impact on a downhill, a large inertial force based on the second braking force acts on the occupant. For this reason, the load applied to the occupant from the seat belt increases and the occupant's posture is likely to be disturbed (prone to become a forward leaning posture).

  However, in the present embodiment, the second braking force in the case of a rearward impact on a downhill is made smaller than the first braking force in the case of a forward impact on a downhill, so the load on the occupant from the seat belt is reduced. And disturbance of the posture of the occupant can be suppressed. Thereby, when the airbag is deployed, the impact absorbing effect of the airbag on the occupant can be efficiently exhibited.

  Thereafter, the overall control unit 20 determines whether or not the host vehicle 12 has stopped based on the output signal from the vehicle speed detection unit 22 (step S9). If the overall control unit 20 determines that the host vehicle 12 is not stopped (step S9: NO), the process returns to step S8 and the automatic brake control unit 46 continues the second automatic brake control.

  When it is determined by the overall control unit 20 that the host vehicle 12 has stopped (step S9: YES), the time determination unit 44 determines whether or not the measurement time t of the timer 38 has passed the second braking duration time tb. Is determined (step S10).

  When the time determination unit 44 determines that the measurement time t of the timer 38 has not passed the second braking duration time tb (step S10: NO), the process returns to step S8, and the automatic brake control unit 46 2 Continue automatic brake control. Thereby, for example, it is avoided that the vehicle 12 moves downhill due to a creep phenomenon immediately after stopping. Further, a secondary collision due to an erroneous vehicle operation by the driver immediately after stopping is avoided.

  When the time determination unit 44 determines that the measurement time t of the timer 38 has passed the second braking duration time tb (step S10: YES), the automatic brake control unit 46 stops the second automatic brake control. (Step S11). That is, the automatic brake control unit 46 stops the output of the second automatic brake control signal to the brake actuator 18 and releases the second braking force of each wheel 14. Thus, the driver can operate the vehicle 12 and retreat it to a safe place. At this stage, the current flowchart ends.

  If it is determined in step S2 that the vehicle is located on the uphill at the time of the vehicle collision, the collision determination unit 40 determines whether the vehicle collision is a normal collision or a rear collision. Determination is made (step S12 in FIG. 3). If the collision determination unit 40 determines that the vehicle has a normal collision, the automatic brake control unit 46 performs the third automatic brake control (step S13).

  Specifically, the automatic brake control unit 46 outputs a third automatic brake control signal to the brake actuator 18. Then, the brake actuator 18 outputs a third brake pressure having a magnitude corresponding to the magnitude of the third automatic brake control signal to each brake unit 16, so that a third braking force is generated on each wheel 14. Here, since the third automatic brake control signal is smaller than the second automatic brake control signal, the third braking force is smaller than the second braking force. Accordingly, the vehicle 12 is decelerated at the third deceleration smaller than the second deceleration without depending on the driver's operation of the brake pedal 34.

  When the vehicle collides normally on the uphill, the vehicle 12 is decelerated by gravity, so the vehicle 12 is likely to be at a lower speed than when the vehicle collides on the downhill. Therefore, the third braking force is smaller than the first braking force and the second braking force when the vehicle collides on a downhill. As a result, when the vehicle crashes uphill, the vehicle 12 can be efficiently decelerated, the load applied to the occupant from the seat belt can be reduced, and the pose disturbance of the occupant can be suppressed.

  Subsequently, the overall control unit 20 determines whether or not the host vehicle 12 has stopped based on the output signal from the vehicle speed detection unit 22 (step S14). If the overall control unit 20 determines that the host vehicle 12 is not stopped (step S14: NO), the process returns to step S13 and the automatic brake control unit 46 continues the third automatic brake control.

  If it is determined by the overall control unit 20 that the host vehicle 12 has stopped (step S14: YES), the time determination unit 44 determines whether or not the measurement time t of the timer 38 has passed the third braking duration time tc. Is determined (step S15).

  When the time determination unit 44 determines that the measurement time t of the timer 38 has not passed the third braking duration time tc (step S15: NO), the process returns to step S13, and the automatic brake control unit 46 3 Continue automatic brake control. Thereby, the secondary collision by the driver's incorrect vehicle operation immediately after stopping is avoided.

  When the time determination unit 44 determines that the measurement time t of the timer 38 has passed the third braking duration time tc (step S15: YES), the automatic brake control unit 46 stops the third automatic brake control. (Step S16). That is, the automatic brake control unit 46 stops outputting the third automatic brake control signal to the brake actuator 18 and releases the third braking force of each wheel 14. Thus, the driver can operate the vehicle 12 and retreat it to a safe place. At this stage, the current flowchart ends.

  If it is determined in step S12 that the collision determination unit 40 is a rear collision, the automatic brake control unit 46 performs the fourth automatic brake control (step S17).

Specifically, the automatic brake control unit 46 outputs a fourth automatic brake control signal to the brake actuator 18. Then, the brake actuator 18 outputs a fourth brake pressure having a magnitude corresponding to the magnitude of the fourth automatic brake control signal to each brake unit 16, so that a fourth braking force is generated on each wheel 14. Here, since the fourth automatic brake control signal is larger than the third automatic brake control signal, the fourth braking force is larger than the third braking force. For example, the fourth braking force can be set to a braking force (brake pressure) such that the vehicle deceleration is 0.5G. 1G is 9.8 m / s ² . However, the fourth braking force can be arbitrarily set. Accordingly, the vehicle 12 is decelerated at the fourth deceleration larger than the third deceleration without depending on the driver's operation of the brake pedal 34.

  When the vehicle crashes on the uphill, the vehicle 12 is decelerated by gravity, and therefore, the vehicle 12 tends to be at a lower speed than the case where the vehicle collides on the downhill. Therefore, the fourth braking force is smaller than the first braking force and the second braking force when the vehicle collides on a downhill. Further, when the vehicle 12 collides rearward on the uphill, the vehicle 12 is accelerated by receiving the collision energy, so that the vehicle 12 is likely to be at a higher speed than when the vehicle 12 collides normally on the uphill. Therefore, the 4th braking force is made larger than the 3rd braking force at the time of a normal collision on an uphill. As a result, when the vehicle crashes uphill, the vehicle 12 can be efficiently decelerated, the load applied to the occupant from the seat belt can be reduced, and the pose disturbance of the occupant can be suppressed.

  Subsequently, the overall control unit 20 determines whether or not the host vehicle 12 has stopped based on the output signal from the vehicle speed detection unit 22 (step S18). If the overall control unit 20 determines that the host vehicle 12 is not stopped (step S18: NO), the process returns to step S17 and the automatic brake control unit 46 continues the fourth automatic brake control.

  When it is determined by the overall control unit 20 that the host vehicle 12 has stopped (step S18: YES), the time determination unit 44 determines whether or not the measurement time t of the timer 38 has passed the fourth braking duration time td. Is determined (step S19).

  When the time determination unit 44 determines that the measurement time t of the timer 38 has not passed the fourth braking duration time td (step S19: NO), the process returns to step S17, and the automatic brake control unit 46 4 Continue automatic brake control. Thereby, the secondary collision by the driver's incorrect vehicle operation immediately after stopping is avoided.

  When the time determination unit 44 determines that the measurement time t of the timer 38 has passed the fourth braking duration time td (step S19: YES), the automatic brake control unit 46 stops the fourth automatic brake control. (Step S20). That is, the automatic brake control unit 46 stops the output of the fourth automatic brake control signal to the brake actuator 18 and releases the fourth braking force of each wheel 14. Thus, the driver can operate the vehicle 12 and retreat it to a safe place. At this stage, the current flowchart ends.

  According to the present embodiment, the braking force (first braking force and second braking force) of the wheel 14 when the vehicle collides on the downhill is the braking force (third braking force) of the wheel 14 when the vehicle collides on the uphill. And the fourth braking force). That is, when the vehicle collides on a downhill, a relatively large braking force is generated on the wheels 14, so that the vehicle 12 can be efficiently decelerated after the vehicle collision. In addition, when a vehicle collides on an uphill, a relatively small braking force is generated on the wheels 14, so that the load that the occupant receives from the seat belt can be suppressed.

  In addition, the second braking force of the wheel 14 in the case of a rear impact on a downhill is made smaller than the first braking force of the wheel 14 in the case of a forward impact on a downhill. For this reason, even if the vehicle 12 is accelerated after the vehicle is collided by being impacted rearward on a downhill, the load received by the occupant from the seat belt can be suppressed.

  Further, the second braking duration tb that continues to generate the second braking force after stopping when the vehicle is impacted on the downhill is the fourth braking force after stopping when the vehicle is impacted on the uphill. Is longer than the fourth braking duration time td. Therefore, it is possible to avoid the vehicle 12 moving due to the creep phenomenon when the vehicle 12 is rearwardly impacted on a downhill.

  The vehicle control device according to the present invention is not limited to the above-described embodiment, but can of course adopt various configurations without departing from the gist of the present invention.

DESCRIPTION OF SYMBOLS 10 ... Vehicle control apparatus 12 ... Vehicle 14 ... Wheel 20 ... Overall control unit 22 ... Vehicle speed detection part 24 ... Collision detection sensor 26 ... Inclination detection part 40 ... Collision judgment part 42 ... Inclination road judgment part 44 ... Time judgment part 46 ... Automatic Brake control unit

Claims (3)

Inclination detecting means for detecting the inclination of the road surface on which the vehicle is located at the time of a vehicle collision;
An automatic brake control unit that automatically generates a braking force on a wheel without depending on a brake operation at the time of a vehicle collision, and a vehicle control device comprising:
The automatic brake control unit makes the braking force of the wheel when the vehicle is located on a downhill at the time of a vehicle collision larger than the braking force of the wheel when the vehicle is located on an uphill at the time of a vehicle collision,
The vehicle control apparatus characterized by the above-mentioned. The vehicle control device according to claim 1,
The automatic brake control unit makes the braking force of the wheel when the vehicle is rearwardly impacted on a downhill smaller than the braking force of the wheel when the vehicle is normally impacted on a downhill. Vehicle control device. In the vehicle control device according to claim 1 or 2,
The automatic brake control unit continues to generate a braking force on the wheel until a predetermined braking duration time has elapsed since the vehicle stopped after a vehicle collision,
The vehicle control device according to claim 1, wherein a braking continuation time when the vehicle is rearwardly impacted on a downhill is longer than a braking continuation time when the vehicle is rearwardly impacted on an uphill.

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