JP2006062397A - Device for controlling vehicle behavior when contacting obstacle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a device for controlling vehicle behavior when contacting an obstacle, capable of securing the safety of a driver at a high level, in case where it is impossible to avoid contact with an obstacle and it is judged that no occupant on a front passenger seat exists. <P>SOLUTION: This vehicle is furnished with a contact avoidance judging means to judge whether the self vehicle can avoid the contact with the obstacle in accordance with a relative relation between the self vehicle and the obstacle and a contact time behavior controlling means to control contact time behavior against the obstacle of the self vehicle in the case when itv is judged that it is impossible for the self vehicle to avoid the contact with the obstacle, an assistant driver's seat occupant judging means to judge whether the occupant exists on the assistant driver's seat of the self vehicle or not is provided, and the contact time behavior controlling means is made into a means to generate a yaw moment on the vehicle so as to make contact with the obstacle from the assistant drive's seat side in the case when it is impossible for the self vehicle to avoid the contact with the obstacle and it is judged that no occupant of the assistance driver's seat exists. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention belongs to the technical field of an obstacle contact behavior control apparatus for a vehicle that controls the behavior of the own vehicle when it is in contact with an obstacle when it is impossible to avoid contact with the obstacle.

A device that automatically generates braking force when the vehicle is about to come into contact with an obstacle cannot be avoided by either braking or steering when it can be avoided by either steering or braking. When the first braking force is generated based on the estimated time required until the vehicle becomes incapable of being avoided by either braking or steering, the second braking force is stronger than the first braking force. Is generated. Thereby, when an obstacle can be avoided by one of braking and steering, it is possible to avoid generating an unnecessarily large braking force (see, for example, Patent Document 1).
Japanese Patent Laid-Open No. 2003-112618

  However, in the conventional vehicle behavior control device at the time of obstacle contact, when the vehicle and the obstacle are about to come into contact with each other, the behavior of the vehicle against the obstacle by the automatic braking force is automatically applied. Is controlled to decelerate. For this reason, although the energy at the time of contact between the vehicle and the obstacle can be reduced, if the vehicle comes into contact with the obstacle from the driver's seat side, there is still room for ensuring the safety of the driver. There was a problem that it was possible.

  The present invention has been made paying attention to the above problem, and when it is determined that contact with an obstacle cannot be avoided and the passenger in the passenger seat is absent, the safety of the driver is further improved. An object of the present invention is to provide a vehicle behavior control device at the time of obstacle contact that can be secured at a level.

In order to achieve the above object, in the present invention, contact avoidance determining means for determining whether or not the vehicle can avoid contact with the obstacle based on the relative relationship between the vehicle and the obstacle, and the vehicle is an obstacle. When it is determined that it is impossible to avoid contact with the vehicle, a vehicle having contact behavior control means for controlling the behavior at the time of contact with the obstacle of the own vehicle,
Providing a passenger seat occupant determination means for determining whether there are passengers in the passenger seat of the vehicle,
The behavior control means at the time of the contact is such that the vehicle is in contact with the obstacle from the passenger seat side when it is determined that the vehicle cannot avoid contact with the obstacle and the passenger in the passenger seat is absent. And generating a yaw moment.

  Therefore, in the obstacle contact behavior control device for a vehicle according to the present invention, if it is determined that the vehicle cannot avoid contact with the obstacle and the passenger in the passenger seat is absent, the contact In the hour behavior control means, control is performed to generate a yaw moment in the vehicle so as to contact the obstacle from the passenger seat side. That is, due to the generation of yaw moment at the time of contact with an obstacle, the kinetic energy is greatly reduced until the driver's seat comes into contact with the driver's seat, or the driver's seat is obstructed when it comes in contact with the vehicle contact angle. The phase is shifted to the offset side of the object, and the contact between the driver's seat side and the obstacle can be avoided. As a result, when it is determined that contact with an obstacle is unavoidable and the passenger in the passenger seat is absent, the driver's safety can be ensured at a higher level.

  BEST MODE FOR CARRYING OUT THE INVENTION The best mode for carrying out the obstacle contact behavior control device for a vehicle according to the present invention will be described below based on Example 1 and Example 2 shown in the drawings.

First, the configuration will be described.
FIG. 1 is an overall view showing a vehicle to which the obstacle contact behavior control apparatus of the first embodiment is applied, and FIG. 2 is a control block diagram showing the obstacle contact behavior control apparatus of the first embodiment.
As shown in FIG. 1, the behavior control apparatus for obstacle contact according to the first embodiment includes a left front wheel 1FL, a right front wheel 1FR, a left rear wheel 1RL, a right rear wheel 1RR, a left front wheel brake unit 2FL, Front wheel brake unit 2FR, left rear wheel brake unit 2RL, right rear wheel brake unit 2RR, laser radar 3, passenger seat belt sensor 4, yaw rate sensor 5, electronic control module (ECM) 6, hydro A unit (HU) 7 (braking force generating means), a left front wheel brake hydraulic pipe 8FL, a right front wheel brake hydraulic pipe 8FR, a left rear wheel brake hydraulic pipe 8RL, and a right rear wheel brake hydraulic pipe 8RR It is equipped with.

  The left front wheel brake unit 2FL, the right front wheel brake unit 2FR, and the left rear wheel brake unit 2RL are provided on the left front wheel 1FL, the right front wheel 1FR, the left rear wheel 1RL, and the right rear wheel 1RR, respectively. It is constituted by a disc brake device or a drum brake device having a wheel cylinder through which pressure is guided through each brake hydraulic pressure pipe 8FL, 8FR, 8RL, 8RR.

  The laser radar 3 is a scanning type inter-vehicle distance sensor, and is provided at a vehicle width center position where an obstacle such as a preceding vehicle or a structure in front of the vehicle can be detected. Based on the detection signal from the laser radar 3, the electronic control module 6 detects the relative relationship between the vehicle and the obstacle. In other words, the laser beam is periodically radiated in the forward direction while shifting in the horizontal direction by a certain angle, the reflected light reflected and returned from the obstacle in front is received, and the received timing of the reflected light from the emission timing Based on the time difference until, the distance to the obstacle at each angle is detected.

  The passenger seat belt sensor 4 is a sensor that outputs an ON signal when the passenger seat occupant wears the passenger seat belt and the belt is locked. Based on the sensor signal from the passenger seat belt sensor 4, the electronic control module 6 determines the presence or absence of a passenger in the passenger seat.

  The yaw rate sensor 5 is a sensor that detects the yaw rate (Yaw) around the center of gravity of the vehicle, and the electronic control module 6 integrates the detected yaw rate (Yaw) to calculate the vehicle contact angle Yawβ.

  The electronic control module 6 receives signals from the laser radar 3, the passenger seat belt sensor 4, and the yaw rate sensor 5, and determines that the vehicle cannot avoid contact with an obstacle. When it is determined that no occupant is present, a braking force difference between the left and right wheels that causes the vehicle to generate a yaw moment so as to come into contact with the obstacle from the passenger seat side is calculated. That is, as shown in FIG. 2, the electronic control module 6 includes a relative relationship detecting means 6 a that detects a relative relationship between the vehicle and the obstacle based on a signal from the laser radar 3, and a signal from the passenger seat belt sensor 4. Contact occupant presence / absence determination means 6b for determining presence / absence of a passenger on the front passenger seat and contact avoidance for determining whether or not the vehicle can avoid contact with an obstacle based on the relative relationship between the vehicle and the obstacle When it is determined that the determination means 6c and the vehicle cannot avoid contact with the obstacle and the passenger in the passenger seat is absent, the yaw moment is applied to the vehicle so as to contact the obstacle from the passenger seat side. Braking force calculation means 6d for calculating the braking force of each wheel having a difference in braking force for generating. The braking force calculation means 6d receives the yaw rate sensor signal from the yaw rate sensor 5, and calculates the braking force of each wheel so that the vehicle contact angle Yawβ calculated based on the yaw rate matches the target vehicle contact angle Targetβ. The

  The hydro unit 7 is a braking force generating means for generating a braking force on each wheel independently of the brake operation by generating a brake fluid pressure based on a command from the electronic control module 6. The hydro unit 7 includes, for example, an electric oil pump as a brake fluid pressure source, and is shared by a vehicle behavior control device (VDC), an anti-skid control device (ABS), and a traction control device (TCS). ABS / TCS brake fluid pressure unit is used.

Next, the operation will be described.
[Contact behavior control processing]
FIG. 3 is a flowchart showing the flow of the behavior control process at the time of contact executed by the electronic control module 6 of the first embodiment. Each step will be described below (corresponding to the behavior control means at the time of contact).

  In step S1, based on the signal from the scanning laser radar 3, it is determined whether there is an obstacle in front of the host vehicle. If it is determined that there is an obstacle in front of the host vehicle, the process proceeds to step S2. , Start behavior control at the time of contact. If it is determined that there is no obstacle ahead of the host vehicle, the determination in step S1 is repeated.

  In step S2, following the determination that there is an obstacle ahead of the host vehicle in step S1, it is determined based on the signal from the passenger seat belt sensor 4 whether there is an occupant in the passenger seat or not. If it is determined that there is an occupant in the seat, the process proceeds to return, and if it is determined that there is no occupant in the passenger seat, the process proceeds to step S3 (passenger seat occupant determination means).

  In step S3, following the determination in step S2 that there is no passenger in the passenger seat, it is impossible to avoid contact between the vehicle and the obstacle even by braking based on the relative relationship between the vehicle and the obstacle, and steering. If it is possible to avoid contact between the vehicle and the obstacle by at least one of braking and steering, the process proceeds to return. If contact between the host vehicle and the obstacle cannot be avoided by using either braking or steering, the process proceeds to step S4 (contact avoidance determination means). A detailed determination method for determining whether or not the vehicle and the obstacle can avoid contact will be described later.

In step S4, the target vehicle contact angle Targetβ is fetched following the determination that contact between the host vehicle and the obstacle cannot be avoided by using either braking or steering in step S3, and the process proceeds to step S5. .
Here, the “target vehicle contact angle Targetβ” is determined by the structure of the vehicle, but is generally set within the range of ± 30 degrees left and right with respect to the front of the vehicle because the limit of airbag deployment is within the range of the angle. Good to do. For example, when there is no structural restriction, in order to generate the maximum yaw moment while ensuring the deployment of the airbag, the target vehicle contact angle Targetβ is set to 30 degrees, which is the airbag deployment limit angle ( (See FIG. 5).

  In step S5, following the capture of the target vehicle contact angle Targetβ in step S4, yaw rate (Yaw) is detected based on the sensor signal from the yaw rate sensor 5, and the process proceeds to step S6.

  In step S6, following the detection of the yaw rate (Yaw) in step S5, the vehicle contact angle Yawβ is calculated by integrating the yaw rate Yaw (yaw angular velocity), and the process proceeds to step S7.

  In step S7, following the calculation of the vehicle contact angle Yawβ in step S6, it is determined whether or not the vehicle contact angle Yawβ is less than the target vehicle contact angle Targetβ. If Yes, the process proceeds to step S8. If No, step S9 is performed. Migrate to

  In step S8, based on the determination that Yawβ <Targetβ in step S7, the brake fluid pressure that controls the differential pressure to the left and right wheels is controlled so that the driver seat side deceleration> the passenger seat side deceleration, and the process returns. Transition.

  In step S9, following the determination that the vehicle contact angle Yawβ is not less than the target vehicle contact angle Targetβ in step S7, it is determined whether the vehicle contact angle Yawβ exceeds the target vehicle contact angle Targetβ. The process proceeds to S10, and if No, the process proceeds to return.

  In step S10, based on the determination that Yawβ> Targetβ in step S9, the brake fluid pressure that gives the differential pressure to the left and right wheels is controlled so that the driver's seat side deceleration <the passenger seat side deceleration. Transition.

[Contact avoidance judgment between own vehicle and obstacle]
First, the detection signal of the laser radar 3 is read, the relative distance d and the relative speed Vr in the traveling direction of the own vehicle between the obstacle ahead of the own vehicle and the own vehicle are calculated, and the detection signal of the laser radar 3 is further calculated. Based on this, the distance and angle to the left and right edges of the obstacle ahead of the host vehicle are detected. Further, based on these, the lateral movement amount Y necessary for the own vehicle to avoid contact with an obstacle ahead is calculated.

The relative speed Vr is calculated, for example, by performing a differentiation operation or a band pass filter process on the relative distance d. Further, the lateral movement amount Y is detected based on the angle at the left and right edge positions by detecting the left and right edges of the obstacle based on the detection signal of the laser radar 3. That is, as shown in FIG. 4 (a), based on the detection signal of the laser radar 3 and its scanning angle, the angles θ1 and θ2 of the left and right edges of the obstacle relative to the traveling direction of the vehicle are detected. . Then, as shown in FIG. 4 (a), with respect to the obstacle ahead of the host vehicle, the smaller one of the angles θ1 and θ2 of the left and right edges of the obstacle (in the case of FIG. 4 (a), θ1 ) Is selected, and this is set as θ, and the lateral movement amount Y is calculated based on the following equation (1).
Y = d · sin (θ) + Lw / 2 (1)
In the formula, Lw is the width of the vehicle. In the first embodiment, the case where the laser radar 3 is provided at the center of the vehicle width of the vehicle has been described. However, the laser radar 3 is mounted offset in either the left or right direction from the center of the vehicle width. Therefore, it is necessary to consider the offset in the equation (1).

  In addition, when one of the left and right edge angles θ1 and θ2 cannot be detected, such as when the center position of the vehicle is relatively deviated from the center position of the obstacle, the edge is The lateral movement amount Y is calculated by the above formula (1), where θ is the edge angle on the detected side. Here, the case where a scanning laser radar is used as the laser radar 3 has been described in the above case. However, in the case of a beam type laser radar capable of outputting a plurality of beams having a certain width, As shown in FIG. 4 (b), based on the detection signal of the laser radar 3, the front obstacle is detected as existing in a range having a certain width. In the case of FIG. 4B, it is determined that there is an obstacle from the position shifted from the angle θ1 to θ2 in the right direction with respect to the traveling direction of the host vehicle and toward the left direction with respect to the traveling direction.

  In this case, it is assumed that the right edge position of the front obstacle is θ1, which is the minimum value, and this is set to θ, and the lateral movement amount Y is calculated based on the equation (1). Also in this case, when the edge of the obstacle is detected only in the right direction or the left direction with respect to the traveling direction of the own vehicle, the edge angle on the side where the edge can be detected is θ, The lateral movement amount Y is calculated based on the above equation (1).

  Also in this case, when the laser radar 3 is not disposed in the center of the vehicle and is mounted with an offset to the left or right, the equation (1) is corrected in consideration of the offset. . In this way, by calculating the lateral movement amount Y, even when the offset amount of the obstacle with respect to the own vehicle is different, the lateral movement amount for avoiding the steering necessary for each case is calculated and the steering is performed. It is possible to calculate with high accuracy whether or not avoidance is possible.

Next, it is determined whether or not contact with an obstacle ahead of the host vehicle can be avoided by performing a braking operation. This determination condition is set as follows. As shown in FIG. 4A, it is assumed that the distance between the host vehicle and the obstacle ahead of the host vehicle is d, and the relative speed is Vr. At this time, the deceleration that occurs when contact is avoided by braking is a (for example, 8.0 [m / s ² ]), and the dead time until deceleration occurs when the driver depresses the brake pedal. Assuming Td (for example, 0.2 seconds), in order to avoid contact with an obstacle by braking, the relationship between the relative speed Vr and the distance d to the obstacle should satisfy the following equation (2).
d <−Vr · Td + (Vr) ² / (2 · a) (2)
Therefore, whether or not contact with an obstacle ahead of the host vehicle can be avoided by performing a braking operation is determined by the distance d to the obstacle and the relative speed Vr satisfying the equation (2). Depending on whether or not.

Subsequently, it is determined whether or not contact with an obstacle can be avoided by performing a steering operation. First, a time Ty required to move laterally by a lateral movement amount Y necessary to avoid contact with an obstacle is calculated. Here, the steering characteristic of the vehicle can be expressed as follows.
m · v · (r + dB / dt) = 2 · YF + 2 · YR (3)
IZ ・ dr / dt = 2 ・ 1F ・ YF-2 ・ 1R ・ YR (4)
YF = fF [β + (lF / v) · r−θF]
YR = fR [β- (lR / v) · r]
In equations (3) and (4), m is the vehicle weight, IZ is the moment of inertia in the vehicle yaw direction, v is the vehicle speed, r is the yaw rate, β is the vehicle contact angle, and lF is the distance from the vehicle center of gravity to the front wheels. , LR is the distance from the center of gravity of the vehicle to the rear wheel, and YF and YR are lateral forces generated at the front wheel and the rear wheel, respectively. Also, θF is the front wheel steering angle, and it is assumed that the driver steers at a certain steering speed and steers at a certain steering amount maximum value, for example, as shown in FIG. . In FIG. 4 (c), the horizontal axis represents time, the vertical axis represents the steering angle, and the steering angle increases with a certain inclination as time elapses. In other words, the steering angle reaches the maximum steering amount at a certain steering speed. It has come to increase.

  Further, fF and fR are functions representing the correspondence between the tire slip angle and the tire lateral force, and are set as shown in FIG. 4 (d), for example. In FIG. 4 (d), the horizontal axis represents the tire slip angle, the vertical axis represents the tire lateral force, the tire lateral force increases as the tire slip angle increases, and the tire slip angle decreases as the tire slip angle decreases. It is set so that the amount of change in the tire lateral force with respect to the change in is large.

Here, the lateral movement amount Y can be expressed by the following equation (5) from the vehicle speed v, the yaw rate r, and the vehicle body contact angle β.
Y = ∫ [v · sin (∫rdt + β)] dt (5)
Therefore, the time required for the vehicle to move laterally by the lateral movement amount Y necessary for avoidance can be calculated from the equations (3) to (5).

  In addition, since it takes a long time to execute the calculations of equations (3) to (5) online, the calculation is performed offline in advance, and the calculation result is, for example, as shown in FIG. It may be mapped to. In FIG. 4 (e), the horizontal axis represents the amount of lateral movement necessary for steering avoidance, and the vertical axis represents the time required for steering avoidance. The time required for steering avoidance increases as the lateral movement amount necessary for operation avoidance increases, and the time related to operation avoidance increases as the vehicle speed decreases. Therefore, when calculating the time required to move laterally by the lateral movement amount Y necessary to avoid the obstacle, that is, the required time Ty required to avoid contact by the steering operation, the vehicle speed v and the lateral movement amount are calculated. What is necessary is just to search the value of the map corresponding to Y.

When the following equation (6) is established between the estimated time d / Vr until contact and the time Ty required for steering avoidance, it is determined that the contact with the obstacle due to the steering operation cannot be avoided.
d / Vr <Ty (6)
Here, based on the formulas (3) to (6), by determining whether or not contact avoidance by the steering operation is possible, the steering avoidance time is calculated according to the difference in the steering characteristics of the vehicle, Whether the steering avoidance is possible or not is accurately calculated regardless of the different steering characteristics for each vehicle and different steering characteristics in the vehicle speed range. Further, by calculating the vehicle steering avoidance time in consideration of the driver's emergency steering operation characteristics, the emergency steering avoidance time can be calculated more accurately.

[Behavior control action during contact]
If it is determined that no passenger in the passenger seat is present and contact avoidance with the obstacle is impossible by any of the steering operation and the braking operation, in the flowchart of FIG. 3, step S1 → step S2 → step S3 -> Go to Step S4-> Step S5-> Step S6-> Step S7-> Step S8, automatically generate braking force, reduce the contact speed to the obstacle, and contact the driver side slower than the passenger side A vehicle contact angle (yaw moment) is generated in the direction to be generated.

  That is, in step S4, as shown in FIG. 5, the target vehicle contact angle Targetβ set to 30 degrees, which is the limit angle within the range in which the airbag is deployed, is captured. In step S5, the yaw rate (Yaw) is obtained from the yaw rate sensor 5. In step S6, the yaw rate (Yaw) is integrated to calculate the vehicle contact angle Yawβ. In step S7, the vehicle contact angle Yawβ is compared with the target vehicle contact angle Targetβ (30 degrees), and step S8 is performed. Then, the braking force is distributed so that Yawβ = Targetβ, that is, driver seat side deceleration> passenger seat side deceleration.

  As the braking force distribution, for example, when the braking force that maximizes the braking force on the driver's seat side is G1, the braking force on the passenger seat side is set to 80% of G1, so that the driver's seat side deceleration> Set the passenger side deceleration. FIG. 6 is a schematic diagram when the braking force on the passenger seat side is set to G1 × 0.8 with respect to the braking force G1 on the driver seat side, and a yaw moment is generated in the vehicle by giving a braking force difference between the left and right wheels. I can see that Conversely, the braking force on the passenger seat side is further increased beyond the maximum braking force G1 on the driver's seat side so that the wheel on the passenger seat side tends to lock, so that the driver's seat deceleration> passenger's seat deceleration is set. May be.

  If the yaw rate becomes excessive and Yawβ> Targetβ, the process proceeds from step S7 to step S9 to step S10. In step S10, the braking force is distributed so that the driver's seat side deceleration <the passenger's seat side deceleration. Reverse. Thereafter, this is repeated and feedback control is performed so that Yawβ = Targetβ.

As described above, when it is determined that there is no passenger in the passenger seat and it is impossible to avoid contact with an obstacle by either the steering operation or the braking operation, the braking force is automatically generated. By reducing the contact speed to the obstacle and automatically generating a yaw moment so as to come in contact with the obstacle from the passenger side, the following effects are exhibited when the vehicle is in contact with the obstacle.
(a) When only the braking force is automatically generated to reduce the contact speed to the obstacle, as shown in FIG. At the same time. On the other hand, when the control for automatically generating the yaw moment is made so as to come into contact with the obstacle from the passenger seat side, as shown in FIG. Since the yaw moment in the direction is generated, the kinetic energy is reduced by the contact from the passenger seat side to the driver seat side contact (due to the contact speed reduction on the driver seat side), compared with the case of Fig. 7 (a) It is possible to ensure the driver's safety when touching an obstacle.
(b) When only the braking force is automatically generated to reduce the contact speed to the obstacle, as shown in FIG. 8 (a), the contact with the obstacle is on the driver side and the passenger side. At the same time. On the other hand, when control for automatically generating a yaw moment so as to come in contact with an obstacle from the passenger seat side is applied, as shown in FIG. Since the phase is shifted to the side where the side is offset from the obstacle, contact on the driver's seat side can be avoided, and the driver's safety can be ensured when contacting the obstacle.

Next, the effect will be described.
With the obstacle contact behavior control device for a vehicle according to the first embodiment, the following effects can be obtained.

  (1) Contact avoidance judging means for judging whether or not the vehicle can avoid contact with the obstacle based on the relative relationship between the vehicle and the obstacle, and the vehicle cannot avoid contact with the obstacle. A passenger seat that determines whether or not a passenger is present in the passenger seat of the own vehicle in a vehicle having a contact behavior control means for controlling the behavior at the time of contact with the obstacle of the own vehicle. An occupant determination unit is provided, and the contact behavior control unit is configured to detect an obstacle from the passenger side when it is determined that the vehicle cannot avoid contact with an obstacle and the passenger in the passenger seat is absent. The vehicle generates a yaw moment to contact the vehicle so that it is impossible to avoid contact with obstacles and it is determined that the passenger in the passenger seat is absent. Can be secured.

  (2) A hydro unit 7 for generating a braking force on each wheel independently of the brake operation is provided, and the contact behavior control means is provided on the passenger seat side due to the braking force difference between the left and right wheels given by the hydro unit 7. In order to generate a yaw moment in the vehicle so as to come into contact with the obstacle from the vehicle, a vehicle equipped with a hydro unit 7 that guides the brake fluid pressure to each wheel independently uses the existing hydro unit 7 to A yaw moment can be generated in the vehicle at the time of contact.

  (3) The contact behavior control means generates a braking force to decelerate the host vehicle when it is determined that the host vehicle is unable to avoid contact with an obstacle and the passenger in the passenger seat is absent. Since the yaw moment is generated in the vehicle so as to contact the obstacle from the passenger side, the kinetic energy is reduced by the deceleration, and the contact position until the contact started from the passenger side moves to the driver side. Due to the synergistic effect of the kinetic energy reduction effect due to movement, the impact force applied to the driver at the time of contact with the obstacle can be greatly reduced.

  (4) The contact behavior control means controls the yaw moment of the vehicle with the maximum value of the vehicle contact angle at which the airbag operates as a limit. The damage done can be minimized.

  (5) The passenger seat occupant determination means determines whether or not an occupant is present in the passenger seat of the own vehicle based on the sensor signal from the passenger seat belt sensor 4, so that the switch structure is simple and low cost. The presence or absence of a passenger in the passenger seat can be determined with high accuracy while using a simple sensor.

  The first embodiment is an example in which the vehicle contact angle (yaw moment) is controlled by a hydraulic brake, while the second embodiment is an example in which the vehicle contact angle (yaw moment) is controlled by an electric steering.

First, the configuration will be described.
FIG. 9 is an overall view showing a vehicle to which the obstacle contact behavior control apparatus of the second embodiment is applied, and FIG. 10 is a control block diagram showing the obstacle contact behavior control apparatus of the second embodiment.
As shown in FIG. 9, the behavior control apparatus for obstacle contact according to the second embodiment includes a left front wheel 1FL, a right front wheel 1FR, a left rear wheel 1RL, a right rear wheel 1RR, a left front wheel brake unit 2FL, Front wheel brake unit 2FR, left rear wheel brake unit 2RL, right rear wheel brake unit 2RR, laser radar 3, passenger seat belt sensor 4, yaw rate sensor 5, electronic control module (ECM) 6, hydro A unit (HU) 7 (braking force generating means), a left front wheel brake hydraulic pipe 8FL, a right front wheel brake hydraulic pipe 8FR, a left rear wheel brake hydraulic pipe 8RL, and a right rear wheel brake hydraulic pipe 8RR The steering mechanism 9 and a steering motor (M) 10 (steering force generating means) are provided.
That is, a steering mechanism 9 having a steering motor 10 for turning the left and right front wheels 1FL and 1FR independently of the steering operation is added between the left and right front wheels 1FL and 1FR to the apparatus of the first embodiment shown in FIG. It is configured.

  Then, as shown in FIG. 10, the electronic control module 6 includes a relative relationship detection means 6 a that detects a relative relationship between the vehicle and the obstacle based on a signal from the laser radar 3, and a signal from the passenger seat belt sensor 4. Contact occupant presence / absence determination means 6b for determining presence / absence of a passenger on the front passenger seat and contact avoidance for determining whether or not the vehicle can avoid contact with an obstacle based on the relative relationship between the vehicle and the obstacle When it is determined that the determination means 6c and the own vehicle cannot avoid contact with an obstacle and the passenger in the passenger seat is absent, the braking force applied to each wheel is calculated, and from the passenger seat side Braking force / steering force calculating means 6d ′ for calculating a steering force for generating a yaw moment in the vehicle so as to come into contact with an obstacle. The braking force / steering force calculation means 6d ′ receives the yaw rate sensor signal from the yaw rate sensor 5, and calculates the steering force so that the vehicle contact angle Yawβ calculated based on the yaw rate matches the target vehicle contact angle Targetβ. Is done. Since other configurations are the same as those of the first embodiment, the corresponding components are denoted by the same reference numerals and description thereof is omitted.

Next, the operation will be described.
[Contact behavior control processing]
FIG. 11 is a flowchart showing the flow of the contact behavior control process executed by the electronic control module 6 of the second embodiment. Each step will be described below (corresponding to the contact behavior control means). Steps S21 to S27 are the same as steps S1 to S7 of the first embodiment shown in FIG.

  In step S28, based on the determination that Yawβ <Targetβ in step S27, control is performed to apply brake fluid pressure to each of the four wheels so as to automatically generate a braking force by a control command to the hydro unit 7. And go to step S29.

  In step S29, following the application of the brake fluid pressure in step S28, control is performed to give the steering angle to the left and right front wheels 1FL, 1FR in the direction of increasing the steering vehicle contact angle Yawβ by a control command to the steering motor 10. Move to return.

  In step S30, following the determination in step S27 that the vehicle contact angle Yawβ is not less than the target vehicle contact angle Targetβ, it is determined whether the vehicle contact angle Yawβ exceeds the target vehicle contact angle Targetβ. The process proceeds to S31, and if No, the process proceeds to return.

  In step S31, based on the determination that Yawβ> Targetβ in step S30, control is performed to apply brake fluid pressure to each of the four wheels so as to automatically generate a braking force by a control command to the hydro unit 7. And go to step S32.

  In step S32, following the application of the brake fluid pressure in step S31, a control command is given to the left and right front wheels 1FL, 1FR in a direction to decrease the steering vehicle contact angle Yawβ by a control command to the steering motor 10, Move to return.

[Behavior control action during contact]
If it is determined that there is no passenger in the passenger seat and contact avoidance with the obstacle is impossible by any of the steering operation and the braking operation, step S21 → step S22 → step S23 in the flowchart of FIG. -> Step S24-> Step S25-> Step S26-> Step S27-> Step S28-> Step S29, the brake force is automatically generated, the contact speed to the obstacle is reduced, and the driver seat side is moved from the passenger seat side. The vehicle contact angle (yaw moment) is generated in the direction in which the contact is made later.

  That is, in step S24, as shown in FIG. 12, the target vehicle contact angle Targetβ set to 30 degrees, which is the limit angle within the range in which the airbag is deployed, is captured. In step S25, the yaw rate (Yaw) is obtained from the yaw rate sensor 5. In step S26, the yaw rate (Yaw) is integrated to calculate the vehicle contact angle Yawβ. In step S27, the vehicle contact angle Yawβ is compared with the target vehicle contact angle Targetβ (30 degrees), and step S28 is performed. Then, for example, the brake fluid pressure is applied to the four wheels so that the maximum braking force is generated, and in step S29, the front wheel steering angle is applied so that Yawβ = Targetβ, that is, the vehicle contact angle Yawβ is increased. Is done.

  As the front wheel steering angle, for example, the maximum front wheel steering angle with the driver's seat on the inside of the turn is given. As a result, the vehicle contact angle Yawβ (yaw rate) becomes excessive and Yawβ> Targetβ. From step S27, the process proceeds from step S30 to step S31 to step S32. In step S31, for example, brake hydraulic pressure is applied to the four wheels so that the maximum braking force is generated, and in step S32, the vehicle contact angle Yawβ is decreased. The front wheel rudder angle is given in the direction to go. Thereafter, this is repeated and feedback control is performed so that Yawβ = Targetβ.

Next, the effect will be described.
In addition to the effects of (1), (3), (4), and (5) of Example 1, the effects listed below are obtained in the behavior control device for obstacle contact of the vehicle of Example 2. be able to.

(6) A steering motor 10 that steers the left and right wheels independently of the steering operation is provided, and the contact behavior control means uses the turning angle of the left and right wheels given by the steering motor 10 to determine the passenger seat. In order to generate a yaw moment in the vehicle so as to contact the obstacle from the side, a vehicle equipped with a steering mechanism 9 having a steering motor 10 in advance uses the existing steering motor 10 to A yaw moment can be generated in the vehicle at the time of contact.
As in the second embodiment, when automatic braking is used when it is determined that contact avoidance is impossible, the braking force generating means and the yaw moment generating means are independent means. The yaw moment can be effectively generated by the steering angle control while the power is output.

  As described above, the behavior control device for an obstacle contact of the vehicle according to the present invention has been described based on the first embodiment and the second embodiment, but the specific configuration is not limited to these embodiments, and Design changes and additions are permitted without departing from the spirit of the invention according to each claim of the scope.

  In the first embodiment, an example using a hydro unit that controls the brake fluid pressure independently for each wheel is shown as a system for obtaining a braking force difference. If so, it is not limited to the first embodiment. For example, a brake hydraulic unit used in a brake-by-wire system or a semi-brake-by-wire system may be used, and a regenerative brake, an electric motor caliper brake, an electric motor drum brake that does not use hydraulic pressure may be used. You may use things like these.

  In the second embodiment, an example in which an electric steering that steers the front wheels independently of the steering operation is used is shown. However, the front wheels and the rear wheels are steered independently of the steering operation, or the rear wheels are steered. A four-wheel steering system (4WS) that performs steering control independently of the operation can also be used.

  In the first embodiment, an example in which the vehicle contact angle is controlled by a brake is shown. In the second embodiment, an example in which the vehicle contact angle is controlled by a steering is shown, but the vehicle contact angle (yaw moment) is set by using both the brake and the steering. You may make it control.

  In the first and second embodiments, an example in which a passenger seat belt sensor is used as a sensor for determining passengers in the passenger seat is shown, but the present invention is not limited to this. For example, a pressure sensor is installed in the passenger seat. Then, other sensors and switches may be used such as detecting the occupant's seating, or installing an infrared sensor facing the passenger seat to detect the occupant's seating.

  In the first and second embodiments, the behavior control device at the time of obstacle contact in the right-hand drive vehicle is shown, but it can of course be applied to the left-hand drive vehicle.

1 is an overall view showing a vehicle to which an obstacle contact behavior control device according to a first embodiment is applied. It is a control block diagram which shows the behavior control apparatus at the time of the obstacle contact of Example 1. FIG. It is a flowchart which shows the flow of the behavior control process at the time of the contact performed by the electronic control module of Example 1. FIG. It is explanatory drawing for the contact avoidance determination of the own vehicle and an obstruction in Example 1. FIG. It is explanatory drawing which shows the target vehicle contact angle in Example 1. FIG. FIG. 5 is an operation explanatory diagram showing a behavior at the time of contact when one of the left and right wheels is set to the maximum braking force and the other is set to 80% of the maximum braking force in the first embodiment. FIG. 6 is an operation explanatory diagram when the contact moves from the passenger seat side to the driver seat side when the own vehicle and the obstacle are in contact in the first embodiment. FIG. 6 is an operation explanatory diagram when the traveling direction is shifted by the vehicle contact angle and contact on the driver's seat side is avoided in the first embodiment when the own vehicle and the obstacle are in contact with each other. It is a general view which shows the vehicle to which the behavior control apparatus at the time of the obstacle contact of Example 2 was applied. It is a control block diagram which shows the behavior control apparatus at the time of the obstacle contact of Example 2. It is a flowchart which shows the flow of the behavior control process at the time of the contact performed by the electronic control module of Example 2. FIG. In Example 2, it is an operation explanatory view in case the target vehicle contact angle is obtained by front wheel rudder angle control at the time of contact with the own vehicle and an obstacle.

Explanation of symbols

1FL Left front wheel 1FR Right front wheel 1RL Left rear wheel 1RR Right rear wheel 2FL Left front wheel brake unit 2FR Right front wheel brake unit 2RL Left rear wheel brake unit 2RR Right rear wheel brake unit 3 Laser radar 4 Passenger seat belt sensor 5 Yaw rate sensor 6 Electronic Control module (ECM)
7 Hydro unit (braking force generating means)
8FL Left front wheel brake hydraulic pipe 8FR Right front wheel brake hydraulic pipe 8RL Left rear wheel brake hydraulic pipe 8RR Right rear wheel brake hydraulic pipe 9 Steering mechanism 10 Steering motor (steering force generating means)

Claims (6)

Contact avoidance determination means for determining whether or not the vehicle can avoid contact with an obstacle based on the relative relationship between the vehicle and the obstacle;
When it is determined that the vehicle is unable to avoid contact with the obstacle, the behavior control means during contact that controls the behavior of the vehicle when in contact with the obstacle;
In vehicles equipped with
Providing a passenger seat occupant determination means for determining whether there are passengers in the passenger seat of the vehicle,
The behavior control means at the time of the contact is such that the vehicle is in contact with the obstacle from the passenger seat side when it is determined that the vehicle cannot avoid contact with the obstacle and the passenger in the passenger seat is absent. A vehicle behavior control device upon contact with an obstacle characterized by generating a yaw moment. In the vehicle obstacle control operation control device according to claim 1,
A braking force generating means for generating a braking force on each wheel independently of the brake operation is provided,
The contact behavior control means causes the vehicle to generate a yaw moment so as to come into contact with an obstacle from the passenger's seat side based on the braking force difference between the left and right wheels given by the braking force generation means. Obstacle contact behavior control device. In the vehicle obstacle control operation control device according to claim 1,
A steering force generating means for steering the left and right wheels independently of the steering operation is provided.
The contact behavior control means generates a yaw moment so that the vehicle comes into contact with an obstacle from the passenger seat side by the turning angle of the left and right wheels given by the steering force generation means. Obstacle contact behavior control device. In the vehicle obstacle contact behavior control device according to any one of claims 1 to 3,
The behavior control means at the time of contact generates a braking force for decelerating the host vehicle when it is determined that the host vehicle is unable to avoid contact with an obstacle and the passenger in the passenger seat is absent, An obstacle contact behavior control apparatus for a vehicle, wherein a yaw moment is generated in the vehicle so as to contact the obstacle from the passenger side. In the vehicle obstacle contact behavior control device according to any one of claims 1 to 4,
The vehicle behavior control device at the time of obstacle contact of the vehicle, wherein the behavior control device at the time of contact controls the yaw moment of the vehicle with a maximum value of a vehicle contact angle at which the airbag operates as a limit. In the vehicle obstacle contact behavior control device according to any one of claims 1 to 5,
The passenger seat occupant determination means determines whether or not an occupant is present in the passenger seat of the vehicle based on a sensor signal from a passenger seat belt sensor. apparatus.

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