JP4826594B2 - Device for determining fear of rollover of vehicle - Google Patents

Description

  The present invention relates to vehicle behavior control, and more particularly, to a vehicle rollover risk determination device.

  As one of devices for determining the possibility of vehicle rollover in behavior control of a vehicle such as an automobile, as described in Patent Document 1 below, for example, the magnitude of the steering angular velocity is adjusted to the vehicle speed when the vehicle is running. 2. Description of the Related Art Conventionally, a determination device that determines the risk of rollover of a vehicle based on whether or not it is greater than a reference value that is set accordingly has been known.

According to such a determination device, since the risk of the vehicle rollover is determined based on the magnitude of the steering angular velocity, it is possible to determine the risk of the vehicle rollover before the vehicle roll amount actually becomes excessive. it can.
Japanese Patent Laid-Open No. 11-11272

  However, in the conventional determination device as described above, the reference value is variably set according to the vehicle speed. However, since the steering angle is not considered, there is no possibility that the vehicle rolls over depending on the traveling state of the vehicle. If a reference value is set so that such a misjudgment does not occur, there is no risk that the vehicle will roll over. It may be judged.

The present invention has been made in view of the above-described problems in the conventional vehicle rollover risk determination device configured to determine the risk of vehicle rollover based on the magnitude of the steering angular velocity. The main problem of the present invention is to determine the risk of a vehicle rollover more accurately and more reliably than in the prior art by determining the risk of a vehicle rollover based on the steering angle and the steering angular velocity. .
[Means for Solving the Problems and Effects of the Invention]

According to the present invention, the above-mentioned main problem is that, according to the present invention, the risk of vehicle rollover is determined based on the magnitude of the steering angle and the steering angular velocity in the increasing direction. In a situation where the determination device has a situation in which the steering angular velocity in the direction of increasing the angle is equal to or greater than the steering angular velocity reference value , the steering angle is greater than or equal to the steering angle reference value. possibility determination equipment thus be achieved in a vehicle rollover, characterized in that to determine that there is a possibility of the vehicle rollover when.

According to the first aspect of the present invention, since the risk of the vehicle rollover is determined based on the magnitude of the steering angle and the steering angular velocity in the direction of increase, there is a risk of the vehicle rollover based only on the steering angular velocity. It is possible to determine the risk of the vehicle rollover more accurately and reliably than in the case of the conventional determination device to be determined.

In particular, according to the configuration of the first aspect, in a situation where the situation where the magnitude of the steering angular velocity in the additional direction is equal to or greater than the steering angular velocity reference value continues for a predetermined time or more , the magnitude of the steering angle is the steering angle. Since it is determined that the vehicle may roll over when it is equal to or greater than the angle reference value, for example, the magnitude of the steering angle is greater than or equal to the steering angle reference value, and the magnitude of the steering angular velocity in the increasing direction is the steering angular speed reference. Compared with the case where it is determined that there is a risk of vehicle rollover when the value is equal to or greater than the value, the risk of vehicle rollover can be determined accurately and reliably.

Further, according to the present invention, in order to effectively achieve the main problem described above, in the configuration of claim 1, a situation in which the magnitude of the steering angular velocity in the increasing direction is equal to or greater than the steering angular velocity reference value is predetermined. in a situation where the continues time or more, a possibility of the vehicle rollover when the magnitude of the lateral acceleration of the steering angle reference value or magnitude is且one car tanks steering angle is equal to or greater than the lateral acceleration reference value It is comprised so that it may determine that there exists (structure of Claim 2).

According to the second aspect of the present invention, in a situation where the situation where the magnitude of the steering angular velocity in the additional direction is equal to or greater than the steering angular velocity reference value continues for a predetermined time or longer , the magnitude of the steering angle is the steering angle. since it is determined that there is a possibility of the vehicle rollover when the magnitude of the lateral acceleration of the reference is greater than or equal value且one car tanks is above the lateral acceleration reference value, even than the case of the configuration of the first aspect The possibility of vehicle rollover can be determined accurately and reliably.

Further, according to the present invention, in order to effectively achieve the above main problem, in the configuration of claim 2, a situation in which the magnitude of the steering angular velocity in the increasing direction is equal to or greater than the steering angular velocity reference value is predetermined. in a situation where the continues time or more, is not less than the lateral acceleration reference value and vehicle speed is above the vehicle speed reference value magnitude of the lateral acceleration of the steering angle reference is greater than or equal value且one car tanks magnitude of the steering angle It is configured to determine that there is a risk of the vehicle rolling over.

According to the configuration of the above third aspect, in the situation where the situation where the magnitude of the steering angular velocity in the additional direction is equal to or greater than the steering angular velocity reference value continues for a predetermined time or longer , the magnitude of the steering angle is the steering angle. since it is determined that there is a possibility of the vehicle rollover when and speed magnitude of the lateral acceleration is equal to or greater than the lateral acceleration reference value of the reference is greater than or equal to value且one car tanks is above the vehicle speed reference value, the billing The possibility of vehicle rollover can be determined more accurately and reliably than in the case of the configuration of item 2.

According to the present invention, in order to effectively achieve the main problems described above, in the configuration according to any one of claims 1 to 3 , at least one of the reference values is a vehicle speed, a vehicle yaw rate. The vehicle is variably set according to at least one of the lateral accelerations of the vehicle (configuration of claim 4 ).

According to the configuration of the fourth aspect , at least one of the reference values is variably set according to at least one of the vehicle speed, the vehicle yaw rate, and the vehicle lateral acceleration. Therefore, the vehicle speed, the vehicle yaw rate, and the vehicle lateral acceleration are set. Regardless of whether or not each reference value is set to a constant value, it is possible to accurately and surely determine the possibility of the vehicle rollover according to the traveling state of the vehicle.

Further, according to the present invention, in order to effectively achieve the main problem described above, in the configuration according to any one of claims 1 to 4 , the weight of the vehicle is detected, and at least one of the reference values is detected. This is configured to be variably set according to the weight of the vehicle (structure of claim 5 ).

According to the configuration of the fifth aspect , since the weight of the vehicle is detected and at least one of the reference values is variably set according to the weight of the vehicle, the ease of rolling the vehicle depending on the weight of the vehicle. Accordingly, the reference value can be variably set, so that the vehicle can roll over more accurately and reliably than when each reference value is set to a constant value without detecting the vehicle weight. Can be determined.

According to the present invention, in order to effectively achieve the above main problem, in the configuration according to any one of claims 1 to 5, the ease of occurrence of a roll of a vehicle is detected, and the reference At least one of the values is configured to be variably set according to the ease of occurrence of the roll of the vehicle (configuration of claim 6 ).

According to the configuration of the sixth aspect of the present invention, the ease of occurrence of vehicle roll is detected, and at least one of the reference values is variably set according to the ease of occurrence of vehicle roll. It is possible to determine the risk of the vehicle rollover more accurately and reliably than when each reference value is set to a constant value without being detected.

Hereinafter, the present invention will be described in detail with reference to some preferred embodiments and reference examples with reference to the accompanying drawings.
[First Reference Example ]

Figure 1 is a schematic configuration diagram showing a first reference example of the risk judging device rollover of the applied car tanks to behavior control device of a vehicle.

  In FIG. 1, 10FL and 10FR represent the left and right front wheels of the vehicle 12, respectively, and 10RL and 10RR represent the left and right rear wheels, respectively. The left and right front wheels 10FL and 10FR, which are steered wheels, are steered via tie rods 18L and 18R by a rack and pinion type power steering device 16 that is driven in response to turning of the steering wheel 14 by the driver.

  The braking force of each wheel is controlled by controlling the braking pressure of the wheel cylinders 24FR, 24FL, 24RR, 24RL by the hydraulic circuit 22 of the braking device 20. Although not shown in the drawing, the hydraulic circuit 22 includes an oil reservoir, an oil pump, various valve devices, and the like, and the braking pressure of each wheel cylinder is normally driven according to the depression operation of the brake pedal 26 by the driver. It is controlled by the master cylinder 28 and, if necessary, is controlled by the electronic control unit 30 as described later.

  The wheel cylinders of the wheels 10FR to 10RL are respectively provided with pressure sensors 32FR to 32RL for detecting the pressure Pi (i = fr, fl, rr, rl) of the corresponding wheel cylinder, and the steering column to which the steering wheel 14 is connected is provided. Is provided with a steering angle sensor 34 for detecting the steering angle θ.

  The vehicle 12 includes a vehicle speed sensor 36 for detecting the vehicle speed V, a yaw rate sensor 38 for detecting the yaw rate γ of the vehicle, a longitudinal acceleration sensor 40 for detecting the longitudinal acceleration Gx of the vehicle, and a lateral acceleration sensor for detecting the lateral acceleration Gy of the vehicle. 42 is provided. The steering angle sensor 34, the yaw rate sensor 38, and the lateral acceleration sensor 42 detect the steering angle, the yaw rate, and the lateral acceleration, respectively, with the left turning direction of the vehicle being positive.

  As shown in the figure, a signal indicating the pressure Pi detected by the pressure sensors 32FR to 32RL, a signal indicating the steering angle θ detected by the steering angle sensor 34, a signal indicating the vehicle speed V detected by the vehicle speed sensor 36, and a yaw rate sensor 38 The signal indicating the yaw rate γ detected by, the signal indicating the longitudinal acceleration Gx detected by the longitudinal acceleration sensor 40, and the signal indicating the lateral acceleration Gy detected by the lateral acceleration sensor 42 are input to the electronic control unit 30.

  Although not shown in detail in the figure, the electronic control device 30 has, for example, a CPU, a ROM, a RAM, and an input / output port device, which are connected to each other via a bidirectional common bus. Includes a microcomputer.

  The electronic control unit 30 calculates a reference value θ1 of the steering angle based on the vehicle speed V when the vehicle is in a traveling state according to the flowchart shown in FIG. 2 as described later, and based on the magnitude of the steering angle θ. The steering angular velocity reference value θd1 is calculated, and when the steering angle θ is greater than the reference value θ1 and the steering angular velocity θd in the increasing direction is greater than the reference value θd1, the vehicle is in an emergency avoidance steering state, and the vehicle Is determined to roll over.

Although not shown in the flowchart, when the electronic control unit 30 determines that the vehicle is in an emergency avoidance steering state and the vehicle may roll over, the electronic control device 30 applies braking force to the turning outer front wheel, thereby decelerating the vehicle. At the same time, a yaw moment in a direction in which the turning radius increases is applied to the vehicle to prevent the vehicle from overturning. The same applies to other reference examples and embodiments described later.

Next, with reference to the flow chart shown in FIG. 2, control for determining the possibility of rollover of the vehicle in the illustrated first reference example will be described. The control according to the flowchart shown in FIG. 2 is started by closing an ignition switch not shown in the figure, and is repeatedly executed at predetermined time intervals. This also applies to other reference examples and embodiments described later.

  First, at step 10, a signal indicating the steering angle θ is read, and at step 20, it is determined whether the vehicle speed V is equal to or higher than a reference value Vo (positive constant), that is, the vehicle is predetermined. It is determined whether or not the vehicle is traveling at a vehicle speed equal to or greater than the value. If a negative determination is made, the process proceeds to step 70. If an affirmative determination is made, the process proceeds to step 30.

  In step 30, a steering angle reference value θ1 is calculated from a map corresponding to the graph shown in FIG. 6 based on the vehicle speed V so that the vehicle speed V becomes higher. In step 40, the steering angle θ is calculated. Based on the absolute value of the steering angle θ, the steering angular velocity reference value θd1 is calculated from the map corresponding to the graph shown in FIG.

  In step 50, sign θ is a sign of the steering angle θ, and it is determined whether or not sign θ · θ is greater than or equal to the reference value θ1, that is, whether or not the magnitude of the steering angle θ is greater than the reference value. If a negative determination is made, the process proceeds to step 80. If an affirmative determination is made, the process proceeds to step 60.

  In step 60, the time differential value of the steering angle θ is calculated as the steering angular velocity θd, and whether or not sign θ · θd is greater than or equal to the reference value θd1, that is, the steering angular velocity in the increasing direction is the reference value. Whether or not the above situation is large is determined. When an affirmative determination is made, it is determined at step 70 that the vehicle is in an emergency avoidance steering state, and when a negative determination is made, a normal determination is made at step 80. It is determined that the vehicle is in the steering state.

Thus, according to the first reference example shown in the figure, in a situation where the vehicle travels at a vehicle speed equal to or higher than the predetermined value Vo, the steering angle θ is greater than the reference value θ1 and the steering angular velocity in the direction of increase is increased. Is equal to or greater than the reference value θd1, it is determined that the vehicle is in an emergency avoidance steering state, and it is determined that the vehicle may roll over.

Therefore, according to the first reference example shown in the figure, the vehicle rolls over more accurately and reliably than in the case of the conventional determination device that determines whether or not the vehicle may roll over only by the steering angular velocity. It is possible to determine whether or not there is a fear, and it is determined that there is a possibility that the vehicle rolls over although there is no fear that the vehicle rolls over. Therefore, the risk of determining that there is no risk of rollover can be reliably reduced.

In particular, according to the first reference example shown in the drawing, the steering angle reference value θ1 is variably set according to the vehicle speed V so as to decrease as the vehicle speed V increases. It is possible to determine whether or not there is a possibility that the vehicle rolls over more accurately and reliably than in the case where it is constant.

Further, according to the first reference example shown in the drawing, the steering angular velocity reference value θd1 is variably set in accordance with the magnitude of the steering angle θ so that it becomes smaller as the magnitude of the steering angle θ increases. The vehicle may roll over more accurately and reliably than when the steering angular velocity reference value θd1 is constant regardless of the size of the vehicle or when the steering angular velocity reference value θd1 is also variably set according to the vehicle speed V. It can be determined whether or not there is.

For example, when the reference value θ1 of the steering angle and the reference value θd1 of the steering angular velocity are constant when a certain vehicle speed V is seen, it is determined that there is a possibility that the vehicle may roll over in FIG. Although the hatched area is shown, according to the first reference example shown in FIG. 16, it can be determined that there is a possibility that the vehicle may roll over in the area where the left-down hatched area is given in FIG. As a result, even in a region where the steering angle θ is small but the steering angular velocity θd in the increasing direction is high, or in a region where the steering angular velocity θd in the increasing direction is low but the steering angle θ is large, the region is surely and reliably. It is possible to determine whether or not the vehicle may roll over.

In the first reference example shown in the drawing, the steering angle reference value θ1 is variably set according to the vehicle speed V so as to decrease as the vehicle speed V increases, and the steering angle decreases as the size of the steering angle θ increases. The reference value θd1 of the angular velocity is variably set according to the magnitude of the steering angle θ, but the reference value θd1 of the steering angular velocity is variably set according to the vehicle speed V so as to decrease as the vehicle speed V increases. steering angle reference value θ1 of the larger size decreases as the steering angle speed may be modified to be variably set in accordance with the magnitude of the steering angle speed.

Further, in the first reference example shown in the figure, the emergency avoidance steering state is established when the magnitude of the steering angle θ is equal to or greater than the reference value θ1 and the steering angular velocity in the increasing direction is equal to or greater than the reference value θd1. However, with Gy1 as a positive constant reference value, the magnitude of the steering angle θ is equal to or greater than the reference value θ1, and the steering angular velocity in the increasing direction is equal to or greater than the reference value θd1. Further, the correction may be made so that the emergency avoidance steering state is determined when the sign θ · Gy is equal to or larger than the reference value Gy1.
[Second Reference Example ]

FIG. 3 is a flow chart showing a vehicle rollover risk determination control routine in the second reference example .

As shown in FIG. 3, steps 110 and 120 are executed in the same manner as in steps 10 and 20 in the first reference example , respectively, and when a negative determination is made in step 120, Proceeding to 210, when an affirmative determination is made, a reference value of the steering angular speed is obtained from the maps corresponding to the graphs shown in FIGS. A value for setting the reference value for the steering angle increase amount based on the vehicle speed V and the map corresponding to the graph shown in FIG. Δθ is calculated.

  In step 140, it is determined whether or not the flag Fp is 0 and the sign θ · θd is greater than or equal to the reference value θd2, and if a negative determination is made, the process proceeds to step 160 as it is, and an affirmative determination is made. In step 150, the flag Fp is set to 1, the steering angle increase reference value θc is set to the current steering angle value θ, and the timer starts counting.

  In step 160, it is determined whether or not the flag Fp is 1 and the count value T of the timer is equal to or less than a reference value To (positive constant), that is, from the time when an affirmative determination is made in step 140. It is determined whether or not the elapsed time is equal to or less than To, and if an affirmative determination is made, the process proceeds directly to step 180. If a negative determination is made, the flag Fp is reset to 0 in step 170. At the same time, the timer count is stopped.

  In step 180, it is determined whether or not the flag Fp is 1. If a negative determination is made, the process proceeds to step 210. If an affirmative determination is made, the process proceeds to step 190.

  In step 190, sign θ · θ is greater than or equal to reference value θ2, vehicle speed V is greater than or equal to reference value V2 (a positive constant greater than or equal to Vo), and sign θ · θ is greater than or equal to reference value θc + Δθ for determining the steering angle increase amount It is determined whether or not sign θ · Gy is greater than or equal to a reference value Gy2 (positive constant). If an affirmative determination is made, it is determined in step 200 that the vehicle is in an emergency avoidance steering state, and a negative determination is made. Is performed, it is determined in step 210 that the vehicle is in the normal steering state.

Thus, according to the second reference example shown in the figure, the flag Fp is set to 1 when the steering angular velocity in the increasing direction exceeds the reference value θd2 in a situation where the vehicle travels at a vehicle speed of the predetermined value Vo or higher. Then, the reference value θc of the steering angle increase amount is set to the current value θ of the steering angle, and the timer count is started. The steering angle θ is greater than the reference value θ2 and the vehicle speed V is equal to the reference value V2 before the predetermined time To elapses from the time when the steering angular velocity in the increasing direction becomes equal to or greater than the reference value θd2. In the situation where the lateral acceleration Gy of the vehicle is equal to or greater than the reference value Gy2, the emergency avoidance steering state is established when the magnitude of the steering angle θ is increased by more than the reference value θc + Δθ in the increasing direction. It is determined that there is a vehicle, and it is determined that the vehicle may roll over.

Therefore, according to the second reference example shown in the figure, as in the case of the first reference example described above, in the case of the conventional determination device that determines whether or not there is a possibility that the vehicle rolls over only by the steering angular velocity. It is possible to accurately and surely determine whether or not there is a possibility that the vehicle rolls over, by determining the situation in which the steering is performed at a higher steering speed more accurately and reliably. Reliable reduction of the risk of determining that there is no risk of rollover despite the risk of the vehicle rolling over, or that there is no risk of rollover despite the risk of the vehicle rolling over can do.

In particular, according to the second reference example shown in the drawing, the reference value θd2 of the steering angular velocity, the reference value θ2 of the steering angle, and the value Δθ that sets the reference value of the steering angle increase amount are set to the vehicle speed V so that it decreases as the vehicle speed V increases. Therefore, it is possible to determine whether or not there is a possibility that the vehicle rolls over more accurately and reliably than when any of these reference values is constant regardless of the vehicle speed V. it can.
[ First embodiment]

FIG. 4 is a flowchart showing a vehicle rollover risk determination control routine according to the first embodiment of the present invention applied to the vehicle behavior control device.

As shown in FIG. 4, steps 310 and 320 are executed in the same manner as in steps 10 and 20 in the first reference example , respectively, and when a negative determination is made in step 320, steps are executed. The process proceeds to 390, and when an affirmative determination is made, a reference value of the steering angular speed is obtained from the maps corresponding to the graphs shown in FIGS. 11 and 12, respectively, based on the vehicle speed V so that the vehicle speed V decreases as the vehicle speed V increases in step 330. θd3 and the reference value θ3 of the steering angle are calculated.

  In step 340, it is determined whether or not sign θ · θd is greater than or equal to the reference value θd3, that is, whether or not the steering angular velocity in the increasing direction is high. In step 350, the timer count value T is incremented by ΔT using ΔT as the cycle time of the routine shown in FIG. 4. If a negative determination is made, the timer count value T is reset to 0 in step 360. Is done.

  In step 370, the timer count value T is greater than or equal to the reference value T3 (positive constant), the sign θ · θd is greater than or equal to the reference value θ3, and the vehicle speed V is greater than or equal to the reference value V3 (positive constant greater than Vo). It is determined whether or not sign θ · Gy is greater than or equal to the reference value Gy3. If an affirmative determination is made, it is determined in step 360 that the vehicle is in an emergency avoidance steering state, and if a negative determination is made, a step is performed. At 390, it is determined that the vehicle is in the normal steering state.

Thus, according to the illustrated first embodiment, the situation where the vehicle is traveling at a vehicle speed equal to or higher than the predetermined value Vo and the steering angular velocity in the increasing direction is equal to or higher than the reference value θd3 continues for the predetermined time T3 or longer. When the steering angle θ is equal to or greater than the reference value θ3, the vehicle speed V is equal to or greater than the reference value V3, and the lateral acceleration Gy of the vehicle is equal to or greater than the reference value Gy3. It is determined that the vehicle is in an emergency avoidance steering state, and it is determined that the vehicle may roll over.

Therefore, according to the illustrated first embodiment, as in the case of the first and second reference examples described above, a conventional determination device for determining whether or not there is a possibility of the vehicle rolling over only by the steering angular velocity. It is possible to determine whether or not there is a possibility that the vehicle rolls over more accurately and reliably than in the case of It is possible to reliably reduce the possibility of making a determination or determining that there is no risk of rollover in spite of the possibility of the vehicle rolling over.

  Particularly, according to the first embodiment shown in the figure, the steering angular velocity reference value θd3 and the steering angle reference value θ3 are variably set according to the vehicle speed V so as to decrease as the vehicle speed V increases. It is possible to determine whether or not there is a possibility that the vehicle rolls over more accurately and reliably than when any of these reference values is constant.

Note In the first illustrated embodiment, in the situation where the status steering angular velocity of the turning-increasing direction is the reference value θd3 above is continued for a predetermined time T3 or more, the size of the steering angle θ The emergency avoidance steering state is determined when the reference value θ3 or more, the vehicle speed V is more than the reference value V3, and the lateral acceleration Gy of the vehicle is more than the reference value Gy3. and that although the condition may be omitted for the lateral acceleration Gy of the vehicle speed V or vehicle.
[ Third reference example ]

FIG. 5 is a flowchart showing a vehicle rollover risk judgment control routine in the third reference example of the present invention applied to the vehicle behavior control device.

  As shown in FIG. 5, steps 410 and 420 are executed in the same manner as in steps 10 and 20 in the first reference example, respectively, and when a negative determination is made in step 420, steps are performed. Proceeding to 480, when an affirmative determination is made, the weight of the steering angle and the steering angular velocity are summed from the maps corresponding to the graphs shown in FIGS. 13 and 14, respectively, so that the vehicle speed V becomes smaller in step 430. The reference value θsd4 and the steering angle reference value θ4 are calculated.

In step 440, the larger the absolute value of the steering angle θ, the smaller the weight K1 of the steering angle θ and the larger the weight K2 of the steering angular velocity θd are shown in FIG. 15 based on the absolute value of the steering angle θ. K1 and K2 are calculated from the map corresponding to the graph, and in step 450, the weight sum θsd of the steering angle θ and the steering angular velocity θd is calculated according to the following equation 1.
θsd = K1 ・ signθ + K2 ・ signθ ・ θd (1)

In step 460, the weight sum θsd is greater than or equal to the reference value θsd4, sign θ · θ is greater than or equal to the reference value θ4, and the vehicle speed V is greater than or equal to the reference value V4 (a positive constant greater than or equal to Vo) and sign θ · G y. Is determined to be greater than or equal to a reference value Gy4 (a positive constant). If an affirmative determination is made, it is determined in step 470 that the vehicle is in an emergency avoidance steering state, and if a negative determination is made. In step 480, it is determined that the vehicle is in the normal steering state.

Thus, according to the third reference example shown in the figure, in a situation where the vehicle travels at a vehicle speed equal to or higher than the predetermined value Vo, the weight sum θsd of the steering angle θ and the steering angular velocity θd is calculated, and the magnitude of the steering angle θ is calculated. Is equal to or greater than the reference value θ4, the vehicle speed V is equal to or greater than the reference value V4, and the magnitude of the lateral acceleration Gy of the vehicle is equal to or greater than the reference value Gy4, the weight sum θsd is equal to or greater than the reference value θsd4. Is determined to be in the emergency avoidance steering state, and it is determined that the vehicle may roll over.

Therefore, according to the third reference example shown in the figure, as in the case of the first and second reference examples and the first embodiment described above, it is determined whether or not there is a possibility that the vehicle rolls over only by the steering angular velocity. Therefore, it is possible to determine whether or not there is a possibility that the vehicle rolls over more accurately and reliably than in the case of the conventional determination device. It is possible to reliably reduce the possibility of determining that there is no risk of rollover despite the possibility of determining that there is a risk of rollover, even though the vehicle may roll over.

In particular, according to the third reference example shown in the drawing, the reference value Gy4 of the weight sum θsd and the reference value θ4 of the steering angle are variably set according to the vehicle speed V so as to decrease as the vehicle speed V increases. Therefore, it is possible to determine whether or not there is a possibility that the vehicle rolls over more accurately and reliably than when any of these reference values is constant.

Further, according to the third reference example shown in the figure, the weight K1 of the steering angle θ and the weight K2 of the steering angular velocity θd are variably set so that the larger the absolute value of the steering angle θ, the smaller the weight K1 and the larger the weight K2. Therefore, it can be determined whether or not there is a possibility that the vehicle rolls over more accurately and reliably than when the weights K1 and K2 are constant.

  Although the present invention has been described in detail with respect to specific embodiments, the present invention is not limited to the above-described embodiments, and various other embodiments are possible within the scope of the present invention. It will be apparent to those skilled in the art.

For example, in the second and third reference examples and the first embodiment described above, the vehicle speed V and the lateral acceleration Gy of the vehicle are equal to or higher than the corresponding reference values in steps 190, 370, and 460, respectively. Although it is set as a condition for determining that it is an emergency avoidance steering state, at least one of these conditions may be omitted.

In the second and third reference examples and the first embodiment described above, each reference value is variably set according to the vehicle speed V. However, each reference value is related to the vehicle speed V. Alternatively, it may be set to a constant value, or may be modified to be variably set according to the yaw rate γ of the vehicle or the lateral acceleration Gy of the vehicle.

In the second and third reference examples and the first embodiment described above, it is determined in steps 190, 370, and 460 whether or not the vehicle speed V is equal to or higher than the reference value Vo. However, this determination may be omitted.

1 is a schematic configuration diagram illustrating a first reference example of a vehicle rollover possibility determination device applied to a vehicle behavior control device. FIG. 7 is a flowchart showing a vehicle rollover risk determination control routine in a first reference example. 10 is a flowchart showing a vehicle rollover risk determination control routine in a second reference example. 5 is a flowchart showing a vehicle rollover risk determination control routine according to the first embodiment of the present invention applied to a vehicle behavior control device. 12 is a flowchart showing a vehicle rollover risk determination control routine in a third reference example . It is a graph which shows the relationship between the vehicle speed V and the reference value (theta) 1 of a steering angle in a 1st reference example. 7 is a graph showing a relationship between an absolute value of a steering angle θ and a reference value θd1 of a steering angular velocity in a first reference example. It is a graph which shows the relationship between the vehicle speed V and the reference value (theta) d2 of a steering angular velocity in a 2nd reference example. It is a graph which shows the relationship between the vehicle speed V and the reference value (theta) 2 of a steering angle in a 2nd reference example. It is a graph which shows the relationship between the vehicle speed V and the value (DELTA) (theta) which sets the reference value of the steering angle increase amount in a 2nd reference example. It is a graph which shows the relationship between the vehicle speed V in 1st embodiment, and the reference value (theta) d3 of steering angular velocity. It is a graph which shows the relationship between the vehicle speed V and reference value (theta) 3 of a steering angle in 1st embodiment. It is a graph which shows the relationship between the vehicle speed V in the 3rd reference example , and the reference value (theta) sd4 of the weight sum of a steering angle and a steering angular velocity. It is a graph which shows the relationship between the vehicle speed V and the reference value (theta) 4 of a steering angle in the 3rd reference example . 12 is a graph showing the relationship between the absolute value of the steering angle θ, the weight K1 of the steering angle θ, and the weight K2 of the steering angular velocity θd in the third reference example . 7 is a graph showing a region that is determined to be in an emergency avoidance steering state in the first reference example by a relationship between an absolute value of a steering angle θ and a steering angular velocity θd in a direction of increasing.

Explanation of symbols

10FR to 10RL ... wheel 20 ... brake device 28 ... master cylinder 30 ... electronic control device 32FR-32RL ... pressure sensor 34 ... steering angle sensor 36 ... vehicle speed sensor 38 ... yaw rate sensor 40 ... longitudinal acceleration sensor 42 ... lateral acceleration sensor

Claims (6)

Use the vehicle rollover risk determination device to determine the risk of vehicle rollover based on the size of the steering angle and the steering angular velocity in the additional direction. The vehicle is characterized in that it is determined that there is a risk of the vehicle rollover when the magnitude of the steering angle is equal to or greater than a steering angle reference value in a situation where the situation is continued for a predetermined time or more. A device for determining the possibility of rollover. In a situation in which the steering angular velocity in the direction of increase is greater than or equal to the steering angular velocity reference value has continued for a predetermined time or longer , the steering angle magnitude is greater than or equal to the steering angle reference value and the lateral acceleration of the vehicle 2. The vehicle rollover risk determination device according to claim 1, wherein the vehicle rollover risk determination unit determines that there is a risk of vehicle rollover when the size of the vehicle is equal to or greater than a lateral acceleration reference value. In a situation in which the steering angular velocity in the direction of increase is greater than or equal to the steering angular velocity reference value has continued for a predetermined time or longer , the steering angle magnitude is greater than or equal to the steering angle reference value and the lateral acceleration of the vehicle The risk of vehicle rollover according to claim 2, wherein it is determined that the vehicle may roll over when the magnitude of the vehicle is greater than or equal to a lateral acceleration reference value and the vehicle speed is greater than or equal to the vehicle speed reference value. Judgment device.   4. The vehicle rollover according to claim 1, wherein at least one of the reference values is variably set according to at least one of a vehicle speed, a vehicle yaw rate, and a vehicle lateral acceleration. 5. Apprehension determination device.   5. The vehicle may roll over according to claim 1, wherein the weight of the vehicle is detected, and at least one of the reference values is variably set according to the weight of the vehicle. Judgment device.   The ease of occurrence of a roll of a vehicle is detected, and at least one of the reference values is variably set according to the ease of occurrence of the roll of the vehicle. The vehicle risk determination device described above.

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