Vehicle posture control device during side impact

Abstract

To disperse and absorb with good efficiency an impact load at the time of side collision.SOLUTION: A side collision attitude control device has an under air cover 17r, an under cover 11, and a control unit 21. The under air bag 17r is located at a lower part of a floor panel 7 of an own vehicle, and the under cover 11 covers an undersurface of the under air bag 17r. In both sides of the under cover 11 in a width direction, a reinforcement 13r side is joined with weaker joining force than a side sill 4r side with respect to a side sill 4r and a reinforcement 13r which are provided in a vehicle width direction of the floor panel 7. The control unit 21 determines a time (collision prediction time) |ΔT| when an approaching vehicle S, which approaches the own vehicle M from the side, collides with the own vehicle, and immediately before reaching this collision prediction time |ΔT|, a part of the under cover 11, which is joined with weak joining force, is separated to inflate and expand the under air bag 17r.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present invention relates to a vehicle attitude control device for controlling the attitude of a host vehicle when subjected to a side collision. [Background technology]

[0002] Conventionally, when a vehicle approaching from the side of a vehicle (approaching vehicle) collides with a vehicle, a technology is known in which a side airbag, a curtain airbag, or the like is inflated and deployed between the occupant and the side of the vehicle body to mitigate the impact load at the time of the side collision. Alternatively, a technology is known in which a cross member is provided on the side door to disperse and absorb the impact load with this cross member.

[0003] In the event of a side collision, in order for the impact load to be efficiently absorbed by the inflation and deployment of side airbags or curtain airbags, or by the side members, the positional relationship between the host vehicle and an approaching vehicle at the time of the collision becomes important.

[0004] For example, if the approaching vehicle is taller than the vehicle itself, the front bumper of the approaching vehicle is likely to collide with the upper part of the vehicle's side that has a relatively high rigidity, such as the front side frame or side sill, causing the door to deform significantly. As a result, it becomes difficult to secure sufficient space for the side airbag or curtain airbag to inflate and deploy.

[0005] As a countermeasure to this, for example, Patent Document 1 (JP 2007-62447 A) discloses a technology in which, when an approaching vehicle (object) approaching the side of the vehicle is detected, a control device predicts whether or not there is an approaching vehicle, and if a collision is predicted, a vehicle height adjustment means is activated to raise the side of the vehicle on the side where the collision is predicted.

[0006] The technology disclosed in this document involves raising the side of the vehicle that is hit, thereby dissipating part of the collision energy of the approaching vehicle into energy for rolling the vehicle itself, thereby absorbing the impact load. [Prior art documents] [Patent documents]

[0007] [Patent Document 1] JP 2007-62447 A Summary of the Invention [Problem to be solved by the invention]

[0008] Incidentally, the raising of the side of the vehicle on the side that has been hit must be completed before the approaching vehicle collides with it. However, the technology disclosed in the above-mentioned document uses a shock absorber as a vehicle height adjustment means and operates this shock absorber with a hydraulic pump, which causes a problem in response and makes it difficult to complete the raising of the side of the vehicle on the side that has been hit before a collision.

[0009] SUMMARY OF THE PRESENT EMBODIMENT An object of the present invention is to provide a vehicle posture control device during a side collision that can disperse and efficiently absorb the impact load during a side collision. [Means for solving the problem]

[0010] The present invention relates to a vehicle posture control device for a side collision, the vehicle posture control device having an under-airbag disposed under a floor panel of the vehicle, an under-cover for covering a lower surface of the under-airbag, and an airbag control unit for controlling the operation of the under-airbag, The under-airbag and the under-cover are disposed on the lower surface of the floor panel in a pair at symmetrical positions across a center in a width direction of the vehicle, or integrally disposed across the width direction, Both sides of the under-cover in the vehicle width direction are joined to at least a pair of frames provided in the vehicle width direction of the floor panel with different joining strengths such that the side with a relatively weaker joining strength is separated when the under-airbag is inflated and deployed, and the airbag control unit includes a collision prediction time calculation unit that calculates a predicted time of collision of the approaching vehicle with a side of the host vehicle based on a traveling state of the host vehicle and an approaching vehicle approaching the host vehicle from the side, and a deployment command calculation unit that inflates and deploys the under-airbag immediately before the predicted collision time calculated by the collision prediction time calculation unit is reached. and a collision position prediction unit that predicts the height of the collision position of the approaching vehicle relative to the host vehicle, and the deployment command calculation unit deploys an under-airbag on the impacted side when it predicts that the impacted side will sink based on the collision position of the approaching vehicle predicted by the collision position prediction unit, and deploys an under-airbag on the non-impacted side immediately after the collision when it predicts that the impacted side will rise. . Effect of the Invention

[0011] According to the present invention, the airbag control unit predicts the time of collision of an approaching vehicle with the side of the vehicle, and just before this predicted collision time is reached, inflates and deploys the under-airbag, separating the side of the under-cover that is joined with a relatively weak joining strength to increase the vehicle height, and so that the impact load from the approaching vehicle is received by the lower part of the vehicle.As a result, the impact load during a side collision can be distributed from the lower part of the vehicle and efficiently absorbed. [Brief description of the drawings]

[0012] [Figure 1] FIG. 2 is an explanatory diagram showing an approaching state of an approaching vehicle relative to a host vehicle; [Diagram 2] Underside view of the vehicle [Diagram 3] A vehicle equipped with a side impact posture control device, [Figure 4] Enlarged view of part IV in Figure 3 [Diagram 5] A cross-sectional view equivalent to FIG. 3 showing the right under-airbag inflated and deployed. [Figure 6] Flowchart showing the attitude control routine during side impact (part 1) [Figure 7] Flowchart showing the attitude control routine during side impact (part 2) [Figure 8] FIG. 1 is an explanatory diagram showing a first collision pattern in which an approaching vehicle collides with the vicinity of a side sill of a host vehicle; [Figure 9] FIG. 13 is an explanatory diagram showing a second collision pattern in which an approaching vehicle collides with the upper portion of the side sill of the host vehicle. [Figure 10] FIG. 11 is an explanatory diagram showing a third collision pattern in which an approaching vehicle collides with a host vehicle having a high center of gravity. [Figure 11] FIG. 11 is an explanatory diagram showing a fourth collision pattern in which an approaching vehicle collides with a position lower than the side sill of the host vehicle. [Figure 12] FIG. 5 is an explanatory diagram showing a fifth collision pattern in which an approaching vehicle collides with a part of the host vehicle above the side sill, which has a low center of gravity. [Figure 13A]FIG. 2 is an explanatory diagram showing a state immediately before a vehicle approaching the host vehicle collides with the host vehicle; [Figure 13B] FIG. 13 is an explanatory diagram showing the state immediately after an approaching vehicle collides with the host vehicle; [Figure 13C] FIG. 13 is an explanatory diagram showing the state after an approaching vehicle collides with the host vehicle; DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. In Fig. 1, M is a vehicle, S is a vehicle approaching the vehicle M from the side (a vehicle approaching from the side), and P is a vehicle traveling in the oncoming lane (an oncoming vehicle). In this embodiment, a road where traffic is restricted to the right is used as an example. Therefore, the left and right are reversed for roads where traffic is restricted to the left.

[0014] FIG. 2 shows the vehicle body underside 1 of the vehicle M. Front tires 2l, 2r are provided on the left and right sides of the front of the vehicle body underside 1, and rear tires 3l, 3r are provided on the left and right sides of the rear. Side sills 4l, 4r are provided as frames on the outside between the left front and rear tires 2l, 3l and between the right front and rear tires 2r, 3r. Furthermore, in order to reduce air resistance, the front and rear of the vehicle body underside 1 are covered by a front undercover 5 and a rear undercover 6, respectively. The left and right side sills 4l, 4r are connected via a floor panel 7 (see FIG. 3), and a floor tunnel 7a is formed in the center of the floor panel 7 in the vehicle width direction.

[0015] A propeller shaft 8, an exhaust pipe 9, etc. are disposed in this floor tunnel 7a. Furthermore, a saddle-shaped fuel tank 10 is disposed in front of the rear undercover 6. The space between this fuel tank 10 and the front undercover 5 is covered by a pair of center undercovers 11 that are formed in a line-symmetrical shape with the floor tunnel 7a in between. Since the left and right center undercovers 11 are line-symmetrical, the same reference numerals will be used in the following description.

[0016] 3, side frames 12l, 12r extending in the front-rear direction are fixed to the underside of the floor panel 7 on the left and right side sills 4l, 4r sides. Furthermore, reinforcements 13l, 13r extending in the front-rear direction are provided on the left and right sides of the floor tunnel 7a. The side sills 4l, 4r and the reinforcements 13l, 13r form a pair of left and right frames.

[0017] The left and right center undercovers 11 are formed by processing a steel plate. As shown in Fig. 3, the left and right center undercovers 11 are each formed with a first contact surface 11a that contacts the left and right side sills 4l, 4r, a second contact surface 11b that contacts the side frames 12l, 12r, and a third contact surface 11c that contacts the reinforcements 13l, 13r. Furthermore, as shown in Fig. 4, a weak portion 11d that opens and deforms when under airbags 17l, 17r, which will be described later, are inflated and deployed is formed on the inside of the first contact surface 11a formed on the center undercover 11 in the vehicle width direction.

[0018] The contact surfaces 11a-11b formed on the left and right center undercovers 11 are joined and fixed to the left and right side sills 4l, 4r, side frames 12l, 12r, and reinforcements 13l, 13r by using the first to third clips 14a-14c, which are support members. The first clip 14a joins the contact surface 11a to the side sills 4l, 4r with a relatively strong joining force, and is not removed (separated) even when the under airbags 17l, 17r, which will be described later, are inflated and deployed. In contrast, the second and third clips 14b, 14c join the contact surfaces 11a, 11b to the side frames 12l, 12r, and reinforcements 13l, 13r with a weaker joining force than the first clip 14a.

[0019] Instead of the first to third clips 14a to 14c, a joining means such as spot welding, arc welding, or laser welding that adjusts the joining strength by adjusting the joining interval may be used to achieve the same function. Alternatively, screws or rivets may be used as the joining means, and the joining strength may be adjusted by the strength of the screws, the fastening interval, or the crimping strength and interval of the rivets. Alternatively, a metal adhesive may be used as the joining means, and the joining strength may be adjusted by the adhesive strength of the metal adhesive or the interval at which it is applied.

[0020] As shown in Figure 3, when the contact surfaces 11a to 11c of the left and right center undercovers 11 are joined to the side sills 4l, 4r, side frames 12l, 12r, and reinforcements 13l, 13r via the first to third clips 14a to 14c, first and second spaces 15a, 15b are formed between the floor panel 7 and the center undercover 11, respectively.

[0021] Reference numerals 16l and 16r denote a pair of under airbag units disposed on the left and right sides in the vehicle width direction. The left and right under airbag units 16l and 16r each include an under airbag 17l, 17r and an inflator 18l, 18r. The under airbag 17l, 17r is folded like a bellows and accommodated in a second space 15b provided in the lower part of the floor panel 7 so as to be able to deploy downward. The inflator 18l, 18r generates high-pressure gas to be supplied to the under airbag 17l, 17r, and is fixed to the floor panel 7 exposed in the second space 15b.

[0022] Each of the inflators 18l, 18r is individually operated by an operation signal from an under-airbag control unit (U / AB_ECU) 21 serving as an airbag control unit, and high-pressure gas is generated by this operation signal. The U / AB_ECU 21 is composed of a microcontroller having a CPU, RAM, ROM, rewritable non-volatile memory (flash memory or EEPROM), and peripheral devices.

[0023] The ROM stores programs and fixed data (particularly, in this embodiment, the specification data of the vehicle M) necessary for the CPU to execute each process. The RAM is provided as a work area for the CPU, and temporarily stores various data for the CPU. The CPU is also called an MPU (Microprocessor) or a processor.

[0024] Travel data of the host vehicle M, information on the vehicle S approaching from the side, and side impact (side collision) pre-crash information are input to the input side of this U / AB_ECU 21. The specification data of the host vehicle M includes the vehicle width, the center of gravity position at the time of shipment, the ground clearance (median value of the width in the height direction) of the side sills 4l, 4r, the time required for the under airbags 17l, 17r to fully inflate after the U / AB_ECU 21 outputs an operation instruction signal to the inflators 18l, 18r (deployment delay time), and the like.

[0025] The center of gravity position may be corrected by detecting changes due to the number of passengers or cargo using a sensor that detects the amount of expansion and contraction of the suspension mounted on each wheel (which may be a suspension arm), a sensor that detects each acceleration during driving, a sensor that detects the inclination state of the vehicle, etc. The deployment delay time is a fixed value (for example, 0.03 to 0.1 [sec]) previously obtained through experiments, etc.

[0026] The travel data of the host vehicle M input to the U / AB_ECU 21 includes the vehicle speed (host vehicle speed) detected by a car navigation system (not shown), the host vehicle position (latitude, longitude, altitude), the host vehicle travel direction, etc. In this embodiment, the position of the center of gravity of the host vehicle M is used as the reference for the host vehicle position.

[0027] Furthermore, the information on the side approaching vehicle S input to the U / AB_ECU21 includes the height of the bumper Sb, etc., and is obtained based on lateral environment information detected by omnidirectional recognition sensors and side recognition sensors mounted on the host vehicle M.

[0028] The side impact pre-crash information also includes information indicating the relative traveling state of the vehicle S approaching from the side with respect to the host vehicle M, which is acquired from a side impact pre-crash sensor provided in a well-known side airbag device (not shown) or the like. This side impact pre-crash sensor may be a millimeter wave radar or LiDAR (Light Detection and Ranging) provided near the side door. Alternatively, the above-mentioned omnidirectional recognition sensor or lateral recognition sensor may be used as the side impact pre-crash sensor. Alternatively, the side impact pre-crash information regarding the vehicle S approaching from the side may be acquired from vehicle-to-vehicle communication or road-to-vehicle communication.

[0029] The U / AB_ECU21 predicts the possibility that the side approaching vehicle S will collide with the side of the vehicle M based on side impact pre-crash information (the relative distance between the side door of the vehicle M and the front end of the vehicle S approaching from the side, the relative speed with respect to the vehicle S, etc.).

[0030] When the U / AB_ECU 21 determines from the side impact pre-crash information that a side collision cannot be avoided, it checks the collision pattern based on the input travel data and specification data of the host vehicle M and information on the side approaching vehicle S. Then, it determines which of the under airbag units 16l, 16r should be activated, or neither should be activated.

[0031] Then, when it is determined that either of the under airbag units 16l, 16r should be activated, an activation signal is output at a predetermined timing to the inflator 18l or 18r of the under airbag unit 16l or 16r that is to be activated, thereby inflating and deploying the under airbag 17l or 17r, thereby stabilizing the posture of the vehicle M immediately before the collision.

[0032] The posture control of the host vehicle M during a side collision executed by the U / AB_ECU 21 is specifically performed according to the routines shown in FIG. 6 and FIG.

[0033] This routine is executed at a predetermined calculation cycle after the system is started. First, in step S1, data of the host vehicle M is read. The data of the host vehicle M includes driving data (the road on the road map on which the host vehicle M is driving (the host vehicle driving path), the host vehicle speed, the vehicle acceleration, the host vehicle position, the host vehicle travel direction, etc.) detected by the car navigation system, which indicates the driving state of the host vehicle M, and specification data (vehicle width, center of gravity position at the time of shipment, ground clearance of the side sills 4l, 4r, deployment delay time of the under airbags 17l, 17r, etc.) written in the ROM. The ground clearance of the side sills 4l, 4r is the center position in the height direction.

[0034] Next, the process proceeds to step S2, where information on the vehicle S approaching from the side is read. The information on the vehicle S approaching from the side is acquired based on side environment information detected by an omnidirectional recognition sensor or a side recognition sensor mounted on the vehicle M, or information from vehicle-to-vehicle communication or road-to-vehicle communication. The information on the vehicle S approaching from the side includes the presence or absence of the vehicle S approaching from the side, the ground height of the bumper Sb provided on the vehicle S approaching from the side, etc. The ground height of the bumper Sb is the value at the center in the height direction.

[0035] Next, the process proceeds to step S3, where it is checked from the read information on the vehicle S approaching from the side whether or not the vehicle S approaching from the side has been detected within a predetermined range from the vehicle M, and if not, the process exits the routine. If the vehicle S approaching from the side has been detected, the process proceeds to step S4. The predetermined range is a distance within which a side collision can be avoided by steering control or braking control, and is set in advance through experiments, etc.

[0036] When the process proceeds to step S4, a predicted time (collision prediction time) for determining whether or not the side approaching vehicle S will collide with the side of the vehicle M is calculated, and the process proceeds to step S5. The process in step S4 corresponds to the collision prediction time calculation unit of the present invention.

[0037] This collision prediction time is calculated from, for example, the well-known TTC (Time To Collision) where collision prediction time = (relative distance / relative speed). More specifically, first, from the running state of the side approaching vehicle S, the time Ts at which the side approaching vehicle S (more precisely, the bumper Sb) enters the intersection (at the position indicated by the dashed line in FIG. 1) is obtained. Also, from the running state of the host vehicle M, the time Tm at which the side of the host vehicle M passes through the intersection (at the position indicated by the dashed line in FIG. 1). Then, the absolute value |ΔT| of the difference ΔT between these two times Ts and Tm is set as the collision prediction time.

[0038] Here, the time Ts when the side approaching vehicle S (the bumper Sb) enters the intersection is calculated based on the side impact pre-crash information. Also, the time Tm when the side of the host vehicle M passes through the intersection is calculated based on the driving data of the host vehicle M. Note that the "intersection" referred to here is not limited to road intersections such as crossroads and T-junctions, but also includes roads where the exit of a parking lot intersects with a general road.

[0039] Next, the process proceeds to step S5, where the collision prediction time |ΔT| is compared with the collision avoidance judgment threshold time To. In this case, the closer the collision prediction time |ΔT| is to 0, the higher the probability of a side collision, and conversely, the greater the collision prediction time |ΔT| is from 0, the lower the probability of a collision. In this step S5, the collision prediction time |ΔT| is compared with the collision avoidance judgment threshold time To to determine whether or not it is difficult to avoid a side collision. This collision avoidance judgment threshold time To is set as the upper limit of the time when it becomes difficult to avoid a side collision based on experiments, etc.

[0040] If |ΔT|≦To, it is determined that avoidance is difficult, and the process proceeds to step S6. On the other hand, if |ΔT|>To, it is determined that the collision can be avoided by braking or steering, and the routine is terminated.

[0041] In step S6, the collision position of the vehicle S approaching from the side relative to the host vehicle M is examined based on the ground heights of the side sills 4l, 4r and center of gravity of the host vehicle M, and the ground height of the bumper Sb of the vehicle S approaching from the side. Then, the behavior of the host vehicle M when the bumper Sb of the vehicle S approaching from the side collides with the side of the host vehicle M is predicted.

[0042] As the behavior of the vehicle M in the event of a side collision, for example, the first to fifth collision patterns shown in Fig. 8 to Fig. 12 are assumed, and it is checked which collision pattern it corresponds to. However, these collision patterns are merely examples, and other collision patterns may be added, or different collision patterns may be newly set. The process in step S6 includes the collision position prediction unit of the present invention.

[0043] The characteristics of each collision pattern are described below. Note that the figure illustrates a collision pattern in which a vehicle S approaches from the side collide with the right side of the vehicle M, and the left and right are reversed in the case of a collision with the left side.

[0044] 1) First impact pattern (Fig. 8) The center of gravity of the host vehicle M is at approximately the same height as the side sills 4l, 4r, and the bumper Sb of the vehicle S approaching from the side is at approximately the same height as the side sills 4l, 4r of the host vehicle M. In this collision pattern, the bumper Sb of the vehicle S approaching from the side collides with the side surface of the side sill (4r in the figure) of the host vehicle M, so the host vehicle M is pushed almost horizontally. Therefore, the side sill 4r side of the host vehicle M, which is the hit side, does not sink or rise, so there is no need to increase the vehicle height on the right side.

[0045] 2) Second impact pattern (Fig. 9) The center of gravity of the host vehicle M is slightly higher than the side sills 4l, 4r, and the ground clearance of the bumper Sb of the vehicle S approaching from the side is near the upper ends of the side sills 4l, 4r of the host vehicle M. In this collision pattern, the bumper Sb of the vehicle S approaching from the side rides up onto the side sill 4r of the host vehicle M during a collision, and a force acts on the right side sill 4r to push it downward. Therefore, the vehicle height of the right side of the host vehicle M is increased, and the collision load is received by the side surface of the right side sill 4r, suppressing sinking of the right side.

[0046] 3) Third impact pattern (Fig. 10) The center of gravity of the host vehicle M is located relatively higher than the side sills 4l, 4r, and the height of the bumper Sb of the vehicle S approaching from the side is near the side of the side sills 4l, 4r. In this collision pattern, when the bumper Sb of the vehicle S approaching from the side collides with the side of the host vehicle M, the side sill 4r side tends to rotate in a sinking direction due to a moment because the center of gravity of the host vehicle M is high. Therefore, the vehicle height of the right side, which is the side that is hit by the host vehicle M, is increased to suppress the rotation acting in the sinking direction.

[0047] 4) Fourth impact pattern (Fig. 11) The height of the bumper Sb of the vehicle S approaching from the side is lower than the side sills 4l, 4r. In this collision pattern, when the bumper Sb of the vehicle S approaching from the side collides with the side of the host vehicle M, the bumper Sb of the vehicle S approaching from the side slides under the side sill 4r of the host vehicle M. As a result, a force acts on the side sill 4r to lift it up. Therefore, the vehicle height of the left side, which is the non-collision side of the host vehicle M, is increased to balance the lifting of the side sill 4r.

[0048] 5) Fifth impact pattern (Figure 12) The center of gravity of the host vehicle M is located at approximately the same position as the side sills 4l, 4r, and the height of the bumper Sb of the vehicle S approaching from the side is higher than the side sills 4l, 4r. In this collision pattern, when the bumper Sb of the vehicle S approaching from the side collides with the side of the host vehicle M, the center of gravity of the host vehicle M is low and the bumper Sb presses the side surface above the side sill 4r, so the right side is likely to rotate in a lifting direction due to the moment. Therefore, by raising the vehicle height of the left side, which is the non-collision side, the rotation of the host vehicle M toward the side sill 4l is offset or suppressed.

[0049] In this way, in step S6, the behavior of the host vehicle M due to a side collision is predicted, one of the first to fifth collision patterns is set, and the process proceeds to step S7. In the above-mentioned first to fifth collision patterns, it may be possible to determine which collision pattern applies based on the heights of the side sills 4l, 4r of the host vehicle M and information on the vehicle S approaching from the side without considering the center of gravity position of the host vehicle M.

[0050] In step S7, it is determined whether or not the under airbag of the under airbag unit on the impacted side (16r in Figs. 8 to 12) needs to be deployed, based on the collision pattern set in step S6 above. That is, in the second and third collision patterns (Figs. 9 and 10), it is determined that the under airbag of the under airbag unit on the impacted side (16r in Figs. 9 and 10) needs to be deployed, and the process proceeds to step S8. In addition, in the first, fourth, and fifth collision patterns, it is determined that the under airbag of the under airbag unit on the impacted side (16r in Figs. 8, 11, and 12) does not need to be deployed, and the process jumps to step S14.

[0051] In step S8, the system subtracts the deployment delay time td required for the airbag to deploy from the time when the collision prediction time |ΔT| is reached, i.e., the time Tm when the host vehicle M passes through the intersection, to calculate the airbag deployment instruction time Ta (Ta=Tm-td), and then proceeds to step S9. Then, in step S9, the system starts timing the timer, and proceeds to step S10 to wait until the airbag deployment instruction time Ta is reached. After that, when the airbag deployment instruction time Ta is reached, the system proceeds to step S11, and checks from which direction the side approaching vehicle S is approaching, left or right, based on the side impact pre-crash information, etc.

[0052] If it is determined that the side approaching vehicle S is approaching from the right, the process proceeds to step S12. If it is determined that the side approaching vehicle S is approaching from the left, the process proceeds to step S13. If it proceeds to step S12, a deployment command signal is output to the right under airbag unit 16r, and the process proceeds to step S14. If it proceeds to step S13, a deployment command signal is output to the left under airbag unit 16l, and the process proceeds to step S14.

[0053] When the U / AB_ECU 21 outputs a deployment command signal to the right under airbag unit 16r in step S12, the right under airbag unit 16r ejects high-pressure gas from the inflator 18r to the under airbag 17r. On the other hand, when the U / AB_ECU 21 outputs a deployment command signal to the left under airbag unit 16l in step S13, the left under airbag unit 16l ejects high-pressure gas from the inflator 18l to the under airbag 17l.

[0054] In the following, the operation of the right under airbag unit 16r will be described. Note that the operation of the left under airbag unit 16l is the same as that of the right under airbag unit 16r, and therefore will be described together in parentheses.

[0055] The under-airbag 17r (17l) is housed in a second space 15b formed by the center undercover 11 and the floor panel 7.

[0056] When the under airbag 17r (17l) is inflated and deployed by the high-pressure gas, in the process, it first pushes down the center undercover 11. Then, the second and third clips 14b, 14c that join the contact surfaces 11b, 11c of the center undercover 11 to the side frame 12r (12l) and the reinforcement 13r (13l) with a weak joining force are removed (separated).

[0057] On the other hand, the contact surface 11a of the center undercover 11 is joined to the side sill 4r (4l) by the first clip 14a having a relatively strong joining force. Therefore, even if the under airbag 17r (17l) is suddenly inflated and deployed, the first clip 14a is not removed and the contact surface 11a remains joined to the side sill 4r (4l).

[0058] As a result, the center under-cover 11 is supported at one end by the contact surface 11a, and the free end is pushed down by the inflation and deployment of the under airbag 17r (17l). Then, as shown in Figure 5, the weakened portion 11d (see Figure 4) deforms in the opening direction, causing the free end of the center under-cover 11 to open widely downward and be pressed against the road surface.

[0059] Next, as shown in FIG. 13A, as the under airbag 17r (17l) further inflates and deploys, the reaction force from the road surface causes the under airbag 17r (17l) to push upward the right side of the vehicle M, as indicated by the arrow, and the under airbag 17r (17l) becomes fully inflated and deployed.

[0060] 13B, the bumper Sb of the vehicle S approaching from the side collides with the right side (left side) of the host vehicle M. At that time, because the hit side of the host vehicle M is pushed upward, the bumper Sb of the vehicle S approaching from the side collides near the side sill 4r, pushing and moving the host vehicle M toward the non-hit side as shown by the arrow, and the impact energy at the time of the collision can be dispersed in the front-rear direction and the pushing direction of the host vehicle M, and efficiently absorbed.

[0061] In addition, since the bumper Sb of the vehicle S approaching from the side collides with the side sill 4r (4l) having high rigidity, the side door on the impact side is prevented from being significantly bent into the vehicle interior. As a result, a space for deploying a side airbag or curtain airbag can be secured between the occupant in the vehicle interior and the side door. In addition, the under airbag 17r (17l) is gradually deflated after being fully inflated. At that time, the center under cover 11 is interposed between the road surface and the side sill 4r (4l) to function like a jack, so that the impact side can be kept lifted.

[0062] Thereafter, when the process proceeds from step S7, step S12, or step S13 to step S14, the deployment conditions for the under airbag on the non-crash side are read.

[0063] That is, in the above-mentioned step S6, the fourth and fifth collision patterns (see Figs. 11 and 12) apply. In this case, for example, when the possibility of rollover of the host vehicle M is predicted based on the roll angle, roll rate, etc. received by the host vehicle M after the side collision of the vehicle S approaching from the side, the under airbag on the non-collision side may be deployed immediately after the collision even in the first to third collision patterns. Alternatively, the under airbag on the non-collision side may be deployed uniformly in the first to third collision patterns.

[0064] Then, the process proceeds to step S15, where it is determined whether or not the under airbag of the under airbag unit on the collision side (16l in Figs. 8 to 12) needs to be deployed based on the deployment conditions read in step S14. If it is determined that deployment of the under airbag is not required, the routine ends. If it is determined that deployment of the under airbag is required, the process proceeds to step S16 after a predetermined delay time has elapsed, where the U / AB_ECU 21 outputs a deployment instruction signal to the under airbag unit on the non-collision side (16l in Figs. 8 to 12) and ends the routine. The processes in steps S6 to S16 correspond to the deployment instruction calculation unit of the present invention.

[0065] Then, as shown in Fig. 13C, high pressure gas is ejected from the inflator 18l (18r) of the under airbag unit 16l (16r) on the non-crash side to the under airbag 17l (17r), causing it to inflate and deploy. Note that the operation of the under airbag 17l (17r) after it is inflated and deployed is the same as that of the crashed side described above, and therefore a description thereof will be omitted.

[0066] When the under airbag 17l (17r) on the non-collision side is deployed, the non-collision side is lifted up, and this action generates a resistance force against the rotational moment acting on the vehicle M toward the collided side, preventing rollover.

[0067] In this case, for example, in the second collision pattern shown in Fig. 9 or the third collision pattern shown in Fig. 10, when it is predicted that the struck side of the vehicle M will sink a predetermined amount or more and roll over to the non-struck side due to the reaction based on at least any information such as the collision position of the vehicle S approaching from the side relative to the vehicle M, the collision speed, and the size of the vehicle body of the approaching vehicle S, the under airbag on the non-struck side may be deployed after at least the upper airbag on the struck side is deployed. This makes it possible to prevent the vehicle from rolling over to the non-struck side.

[0068] Similarly, in the fourth collision pattern shown in Fig. 11 and the fifth collision pattern shown in Fig. 12, when it is predicted that the struck side of the vehicle M will be lifted to a predetermined level or more and roll over to the non-struck side based on at least any of information such as the collision position of the vehicle S approaching from the side relative to the vehicle M, the collision speed, and the size of the vehicle body of the approaching vehicle S, the under airbag on the non-struck side may be deployed after the collision. This makes it possible to prevent the vehicle from rolling over to the non-struck side.

[0069] As a result, for example, rollover into an adjacent lane in an oncoming lane or a road with two or more lanes as shown in Figure 1 is prevented. Therefore, secondary damage caused by contact with an oncoming vehicle P or a vehicle traveling parallel in an adjacent lane can be avoided.

[0070] In this manner, in this embodiment, when it is predicted that the vehicle S approaching from the side will collide with the side of the vehicle M, the collision pattern is checked based on the ground height of the center of gravity of the vehicle M, the ground height of the side sill, and the ground height of the bumper Sb of the vehicle S approaching from the side, and the posture is controlled so that the bumper Sb of the vehicle S approaching from the side will collide with the side sill 4l or near 4r, which is a rigid part on the impacted side, by operating the under airbag unit 16r or 16l according to the corresponding collision pattern.

[0071] When an impact load is applied near the side sill 4l or 4r, the vehicle M is pushed toward the non-hit side via the side sill 4l or 4r on the hit side, and as a result, the impact energy at the time of the collision is distributed in the fore-and-aft direction and in the pushing direction of the vehicle M, allowing it to be absorbed efficiently.

[0072] In addition, since the bumper Sb of the vehicle S approaching from the side is caused to collide with the side sill 4l or 4r, which is a rigid portion, the side door is prevented from being bent into the interior, and space can be secured between the occupants in the vehicle interior and the side door to deploy side airbags and curtain airbags.

[0073] Furthermore, if the possibility of rollover of the vehicle M is predicted after a side collision, or by uniformly operating the under airbag unit 16l or 16r on the non-collision side, a resistance force is generated against the rotational moment acting on the vehicle M toward the non-collision side, thereby preventing rollover.

[0074] The present invention is not limited to the above-described embodiment. For example, the left and right under airbags 17l, 17r and the left and right center under covers 11 may be integrally disposed across the width of the underside of the floor panel 7. Also, the front under cover 5 and the rear under cover 6 shown in Fig. 2 may be divided symmetrically in the vehicle width direction. Then, an under airbag unit may be provided in each pair of under covers, and these may be operated in synchronization with the under airbag unit in the center under cover. [Explanation of symbols]

[0075] 1...Underside of the vehicle body, 2l, 2r…Left and right front tires, 3l, 3r…Right and left rear tires, 4l, 4r…Left and right side sills, 5…Front under cover, 6...Rear under cover, 7…Floor panel, 7a…Floor tunnel, 8…Propeller shaft, 9…Exhaust pipe, 10…Fuel tank, 11...Center under cover, 11a~11c...Abutment surface, 11d...Weak part, 12l, 12r…Side frame, 13l, 13r…Reinforcement, 14a~14c…1st~3rd clips, 15a, 15b...first and second space parts, 16l, 16r…Under airbag unit, 17l, 17r…Under airbag, 18l, 18r…inflator, 21...Under airbag control unit, M: Vehicle, P…oncoming vehicle, S: Vehicle approaching from the side, Sb…Bumper, Ta: Airbag deployment instruction time, To: Collision avoidance judgment threshold time, Ts…intersection entry time, td: deployment delay time, |ΔT|…Collision prediction time

Claims

1. An under-airbag disposed under a floor panel of the vehicle; an undercover for covering a lower surface of the under-airbag; an airbag control unit for controlling the operation of the under-airbag; In a vehicle side collision posture control device having The under-airbag and the under-cover are disposed on the lower surface of the floor panel in a pair at symmetrical positions across a center in a width direction of the vehicle, or integrally disposed across the width direction, both sides of the undercover in the vehicle width direction are joined to at least a pair of frames provided in the vehicle width direction of the floor panel with different joining forces such that the sides with a relatively weaker joining force are separated when the under-airbag is inflated and deployed, The airbag control unit is a collision prediction time calculation unit that calculates a collision prediction time of the approaching vehicle with a side of the host vehicle based on a traveling state of the host vehicle and a traveling state of an approaching vehicle approaching the host vehicle from the side; a deployment command calculation unit that inflates and deploys the under-airbag immediately before the collision prediction time calculated by the collision prediction time calculation unit is reached; a collision position prediction unit that predicts a height of a collision position of the approaching vehicle with respect to the host vehicle; having The deployment command calculation unit deploys an under-airbag on the impacted side when it predicts that the impacted side will sink based on the impact position of the approaching vehicle predicted by the collision position prediction unit, and deploys an under-airbag on the non-impacted side immediately after the impact when it predicts that the impacted side will rise A vehicle posture control device during a side collision.

2. When the deployment command calculation unit predicts that the collision-affected side will sink to a predetermined depth or more based on at least any of information such as the collision position of the approaching vehicle predicted by the collision position prediction unit, the collision speed, and the size of the approaching vehicle, the deployment command calculation unit deploys at least an under airbag on the collision-affected side and then deploys an under airbag on the non-collision side.

2. The vehicle attitude control device according to claim 1, wherein the vehicle attitude control device is a vehicle that is in a side collision.

3. The deployment command calculation unit deploys the airbag on the non-collision side after a collision when it predicts that the collision-affected side will be lifted to a predetermined level or more based on at least any of information such as the collision position, collision speed, and size of the approaching vehicle predicted by the collision position prediction unit.

2. The vehicle attitude control device according to claim 1, wherein the vehicle attitude control device is a vehicle that is in a side collision.

4. At least a pair of reinforcements extending in the front-rear direction of the vehicle are disposed on the lower surface of the floor panel at symmetrical positions across a center of the vehicle in the width direction, and the other of the pair of frames is disposed on the outer side of each of the reinforcements in the width direction, Each of the under-covers is joined to the reinforcement with a joining force that is relatively weaker than the joining force of the other of the pair of frames, The under-airbag is stored between the pair of frames and the reinforcement.

4. The vehicle attitude control device during a side collision according to claim 1.

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