JP5416638B2 - Reverse determination device and reverse determination method - Google Patents

Description

  The present invention relates to a reverse determination device and a reverse determination method for determining whether or not a vehicle is moving backward.

  In controlling the vehicle, it is important to determine whether or not the vehicle is moving backward, and various determination methods have been proposed for determining whether or not the vehicle is moving backward. For example, Japanese Patent Laid-Open No. 2004-228561 “detects lateral acceleration and yaw angular velocity acting on the vehicle, and determines whether the vehicle is moving backward based on the direction of lateral acceleration acting on the vehicle and the direction of yaw angular velocity. A vehicle reverse determination method has been proposed. Patent Document 2 proposes “reverse determination means for determining the reverse of the vehicle from the target yaw rate calculated by the target yaw rate calculation means and the actual yaw rate”. That is, Patent Document 1 and Patent Document 2 determine whether the vehicle is moving forward or backward based on the difference in actual lateral acceleration (actual lateral G) with respect to the turning direction indicated by the actual yaw rate at the time of forward travel and reverse travel.

This point will be described more specifically with reference to FIG. In FIG. 9, (a) shows the relationship between the actual yaw rate and the actual lateral G at the time of the left turning forward, and (b) shows the relationship between the actual yaw rate and the actual lateral G at the time of the left turning backward. As shown in FIG. 9, the actual lateral G (GL in FIG. 9) detected by the lateral G sensor always occurs toward the turning center regardless of forward / backward movement. On the other hand, since the actual yaw rate (ω in FIG. 9) detected by the yaw rate sensor indicates the rotational angular velocity of the vehicle, the direction of occurrence is reversed during forward movement and backward movement. In Patent Document 1, etc., this characteristic is used to determine whether the vehicle is moving forward or backward.
In FIG. 9, “●” attached to the center of the vehicle is the position of the center of gravity of the vehicle in plan view.

Japanese Patent No. 3649007 Japanese Patent No. 3775066

However, it has been newly found that the technique of Patent Document 1 and the technique of Patent Document 2 cause an erroneous determination state when turning while reversing.
Therefore, an object of the present invention is to provide a reverse determination device that can determine reverse more appropriately.

  In order to achieve the above-mentioned object, the present inventors have conducted intensive research, and the vehicle motions in the initial stage of reverse turning where the vehicle turns while moving backward and in the stationary period where the turning while moving backward is in a steady state. However, the present invention has been completed by paying attention to the fact that there is a point that should be improved in the early stage of reverse turning.

That is, the present invention which has solved the above problems (claim 1), based on the lateral acceleration applied to the vehicles, and a yaw rate of the vehicle, a retraction device for judging the backward movement of the vehicle. Then, based on the lateral acceleration detected by the lateral acceleration detection means, a rear-axis lateral acceleration calculation unit that calculates a rear-axis lateral acceleration that is a lateral acceleration on the rear axle of the vehicle, and detected by the rear-axis lateral acceleration and the yaw rate sensor And a reverse determination unit that compares the yaw rate with the vehicle to determine whether the vehicle is reverse.

  In this configuration, it is the “rear-axis lateral acceleration” that is compared with the “yaw rate”, and the backward movement of the vehicle is determined based on the comparison result between the two. This action will be described in detail in the embodiments of the invention described later.

  The present invention (Claim 2) that solves the above problem is a reverse determination device that determines the reverse of the vehicle based on the vehicle body speed of the vehicle, the lateral acceleration applied to the vehicle, and the yaw rate of the vehicle. The reverse determination apparatus includes a rear-axis lateral acceleration calculation unit that calculates a rear-axis lateral acceleration that is a lateral acceleration on a rear axle of the vehicle based on the lateral acceleration detected by the lateral acceleration detection unit, and the rear-axis lateral acceleration. Based on the acceleration and the vehicle body speed detected by the vehicle body speed detection means, a trajectory angle rate calculation unit that calculates the trajectory angle rate of the vehicle, and compares the trajectory angle rate with the yaw rate detected by the yaw rate sensor. And a reverse determination unit for determining reverse.

  In this configuration, the “yaw rate” is compared with the “trajectory angle yaw rate (revolution yaw rate)” based on the rear-axis lateral acceleration, and the backward movement of the vehicle is determined based on the comparison result between the two. This action will be described in detail in the embodiments of the invention described later.

  Further, according to the present invention (Claim 3) that solves the above problem, the vehicle includes a behavior control device that generates a yaw moment on the vehicle body by applying a braking force to at least one wheel. When the backward movement of the vehicle is determined, the generation of the yaw moment by the behavior control device is stopped in cooperation with the behavior control device.

  In this configuration, the behavior control device included in the vehicle is controlled based on the determination result using the rear-axis lateral acceleration described above.

Further, the present invention (Claim 4) that solves the above-mentioned problems is that the vehicle body speed detected by the vehicle body speed detecting means, the lateral acceleration applied to the vehicle detected by the lateral acceleration detecting means, and the vehicle detected by the yaw rate sensor. This is a reverse determination method in which the computer that inputs the yaw rate determines whether the vehicle is reverse. In this reverse determination method, the computer acquires the vehicle body speed, the lateral acceleration, the yaw rate , and the acceleration on the rear axle of the vehicle based on the lateral acceleration and the yaw rate. A step of calculating a certain rear-axis lateral acceleration, a step of calculating a trajectory angular rate of the vehicle based on the rear-axis lateral acceleration and the vehicle body speed, and a step of comparing the trajectory angular rate and the yaw rate to determine the reverse of the vehicle It is characterized by including.

  In this configuration, as in the first aspect of the invention, it is the rear-axis lateral acceleration that is compared with the yaw rate, and a computer such as an ECU (Electronic Control Unit) moves the vehicle backward based on the comparison result between the two. It is determined whether or not. This action will also be described in detail in the embodiments of the invention described later.

  ADVANTAGE OF THE INVENTION According to this invention, the reverse determination apparatus etc. which can determine reverse back more appropriately can be provided.

It is a conceptual diagram which shows the structure of the vehicle carrying the reverse determination apparatus which concerns on this invention. It is a figure which shows the relationship between the real yaw rate at the time of reverse of a vehicle, and a reference | standard yaw rate. It is a figure which shows the relationship between the actual yaw rate, locus angle rate, and actual lateral G at the time of reverse of a vehicle. It is a figure which shows relations, such as an actual yaw rate and the actual lateral G, in a vehicle, (a) shows a reverse turning initial stage, (b) shows a reverse turning steady period. It is the functional block diagram which showed the general | schematic function of the reverse determination apparatus which concerns on this invention. (A) is a figure which shows the relationship between the position of the lateral G sensor in an embodiment, and a rear-axis gravity center position, (b) is a figure which shows the relationship between the position of the lateral G sensor in a comparative example, and a vehicle gravity center position. It is a flowchart which shows the operation | movement of determination by the reverse determination apparatus which concerns on this invention. It is explanatory drawing of the effect by the determination apparatus based on this invention which concerns on this invention. It is a figure explaining a prior art, (a) shows the relationship between the actual yaw rate and the actual lateral acceleration when the vehicle moves forward, and (b) shows the relationship between the actual yaw rate and the actual lateral acceleration when the vehicle moves backward. .

  Hereinafter, a mode for carrying out a reverse determination device and a reverse determination method (hereinafter referred to as “embodiment”) according to the present invention will be described in detail with reference to the accompanying drawings.

≪Overall configuration of vehicle≫
As described in the conceptual diagram showing the configuration of the vehicle in FIG. 1, the vehicle V is a four-wheeled vehicle. An engine room is provided in front of the vehicle V, and an engine, a transmission, and the like (not shown) are accommodated in the engine room. The driving force generated by the engine is transmitted to the front wheels. That is, the vehicle V of this embodiment is an FF vehicle.

  The engine room also houses an ECU (Electronic Control Unit) 1 that performs various controls, a yaw rate sensor SY that detects an actual yaw rate, a lateral G sensor SG that detects an actual lateral G, and the like. In addition, the reverse determination part 10 shall be mounted in ECU1. The ECU 1 includes a CPU (Central Processing Unit), an input / output interface, a power supply stabilization circuit, and the like (not shown).

The vehicle V of the present embodiment is configured so that the brake fluid pressure of a wheel cylinder (not shown) of each wheel can be increased or decreased under the control of the ECU 1 regardless of the intention of the occupant. That is, the vehicle V of the present embodiment is equipped with VSA (Vehicle Stability Assist). VSA adds ABS (Anti Lock Brake System) to prevent wheel lock during braking, TCS (Traction Control System) to prevent wheel slipping during acceleration, etc., and adds side slip suppression control during turning to provide a total of three functions. This is a vehicle behavior stabilization control system that controls the vehicle. The function of this VSA is managed in an integrated manner by the ECU 1.
Incidentally, in the present embodiment, the VSA will be described as a vehicle behavior control device that suppresses side slip particularly during turning.

  The lateral G sensor SG is a sensor that detects lateral acceleration (actual lateral G) applied to the vehicle V and outputs it to the ECU 1 and is mounted in the vicinity of the ECU 1 (detailed position will be described later). The yaw rate sensor SY is a sensor that detects the yaw rate of the vehicle V, that is, the change speed of the rotation angle of the vehicle V in the turning direction, and outputs it to the ECU 1, and is mounted in the vicinity of the ECU 1. The vehicle body speed sensor SV is a sensor that detects (estimates) the vehicle body speed of the vehicle V using a detection value of a wheel speed pulse sensor included in each wheel.

  The lateral G sensor SG and the yaw rate sensor SY may be mounted at appropriate places in the casing of the ECU 1, for example, on a substrate in the casing. The vehicle body speed sensor SV may be implemented as software executed by a CPU (not shown) included in the ECU 1. These sensors (SG, SY, SV) are not limited to specific ones.

  In FIG. 1, “●” indicated by a symbol A is the center of gravity position of the vehicle V (vehicle center of gravity position) in plan view. Further, “●” indicated by reference sign B is the center of gravity position of the rear axis of the vehicle V (rear axis center of gravity position) in plan view. Conventionally, the actual lateral G detected by the lateral G sensor SG is converted into the lateral G at the vehicle center-of-gravity position A in the ECU 1 to perform various controls. Details of this point will be described later. Incidentally, the yaw rate has the same value at any position on the vehicle body (there is no influence of the position).

≪Challenges in VSA≫
By the way, the side slip suppression control in the VSA is performed based on a deviation (yaw rate deviation) between the actual yaw rate detected by the yaw rate sensor SY and the standard yaw rate calculated from the steering angle and the vehicle speed (vehicle speed), and the larger the deviation is, the more the deviation is. It is configured to have a large control amount. When the vehicle V moves forward, the actual yaw rate and the normative yaw rate are substantially equal to each other, and the ECU 1 sets the control amount to control the brake fluid pressure so as to cancel out the generated deviation.

However, when the vehicle V is reversing (backward turning), the values of the standard yaw rate and the actual yaw rate are opposite (the actual yaw rate is reversed) as shown in the diagram showing the relationship between the standard yaw rate and the actual yaw rate in FIG. ), A large deviation will occur. For this reason, when the side-slip suppression control by the VSA is performed at the time of reverse, the control is executed even when the side-slip suppression control is originally unnecessary, and the passenger is given an uncomfortable feeling. Therefore, when the vehicle V moves backward, control by VSA is not performed (control prohibition). In other words, the behavior of the vehicle when the front wheel, which is a steered wheel, is moved forward is different from the behavior of the vehicle when the front wheel is moved backward in the traveling direction. It is set to perform suppression control.
Note that it is not necessary to reverse the polarity of either the normative yaw rate or the actual yaw rate at the time of reverse determination. Software development (enormous time and cost) is required.

  For this reason, side slip suppression control by VSA is prohibited at the time of reverse determination as described above, but there is an unconfirmed state in which either forward or reverse can not be determined in forward determination and reverse determination. Depending on the conditions, it may take time to make the determination. If the reverse determination can be confirmed, the side-slip suppression control can be prohibited. However, if it is not yet determined, there is a possibility that the vehicle will move forward. Therefore, the control cannot be prohibited.

Since the actual lateral G and actual yaw rate used for the side slip suppression control and the forward / reverse determination are performed using values at the center of gravity position of the vehicle V (vehicle center of gravity position A in FIG. 1), calculation is performed from the actual yaw rate and actual lateral G. When compared with the trajectory angle rate to be performed (even when compared with the actual lateral G), the following problem occurs. That is, if the trajectory angle rate at the vehicle center of gravity position A is used for the reverse determination, the actual yaw rate and the trajectory angular rate may be in the same direction even though the vehicle V is moving backward. The place to be judged is judged as forward.
That is, it is important to make the reverse determination quickly and accurately.

  FIG. 3 is a diagram showing the relationship between the actual yaw rate, the trajectory angle rate, and the actual lateral G when the vehicle V is turning backward, where the horizontal axis represents time, and the vertical axis represents the actual yaw rate / trajectory angular rate (vehicle center of gravity position). ) / Actual lateral G (vehicle center of gravity position). 3, when the vehicle V moves backward as shown in FIG. 9B of the background art, the sign (direction) should be reversed such that the actual yaw rate is right (clockwise) and the actual lateral G is left. . However, as described above, when the trajectory angle rate (actual lateral G) at the vehicle center of gravity position A is used for reverse determination, the part surrounded by a circle in FIG. The actual yaw rate and trajectory angle rate are in the same direction. For this reason, as described above, it is determined that the place to be determined to be reverse is determined to be forward, and therefore, a reverse determination delay or the like occurs.

  Here, the reason why the actual yaw rate and the trajectory angle rate (actual lateral G) are in the same direction at the beginning of the backward turning that starts turning while going backward as in the circled portion of FIG. 3 will be described. .

FIGS. 4A and 4B are diagrams showing the relationship between the actual yaw rate, actual lateral G, and the like in the vehicle. FIG. 4A shows an initial reverse turning, and FIG. 4B shows a steady reverse turning period. Here, in FIG. 4, “YAWR” is the actual yaw rate. “GY _F ” is the actual lateral G on the front axle (front axis center of gravity position) of the vehicle V, “GY _B ” is the actual lateral G on the rear axle (rear axis center of gravity position) of the vehicle V, and “GY _A ” is This is the actual lateral G at the vehicle gravity center position A. “YAWR” is the same as “ω” in FIG. 9 of the background art.

Considering the case where the steering is operated to the left while the vehicle V is moving backward, at the initial stage of backward turning, as shown in FIG. 4A, first, the front center of gravity position of the vehicle V is steered by turning the front wheels that are steered wheels. Then, the actual lateral G (GY _F ) increases greatly in the right direction. On the other hand, since the rear wheel is not a steered wheel, only a slight side slip occurs on the rear wheel, so that the actual lateral G (GY _B ) also slightly occurs at the position of the center of gravity of the rear axis. Therefore, the actual lateral G (GY _A ) at the vehicle center-of-gravity position A is generated in the right direction of the vehicle V from the relationship between the magnitudes of GY _F and GY _B and the direction. The actual yaw rate (YAWR) is the clockwise direction to the right. That is, the direction of the actual lateral G (GY _A ) (that is, the direction of the trajectory angular rate) and the direction of the actual yaw rate (YAWR) coincide at the initial stage of reverse turning. As a result, a situation where it is determined that the vehicle is moving forward or a situation where neither can be determined may occur.

On the other hand, as the movement (retreat) progresses, the side slip of the rear wheels gradually increases, and the vehicle V shifts to a revolving motion having a lateral G (GY _A ) in the left direction (reverse turning steady phase). FIG. 4 (b) shows the stationary reverse turning steady period. In FIG. 4 (b), the direction of the actual lateral G (GY _F ) at the position of the center of gravity of the front axis of the vehicle V is as shown in FIG. 4 (a). Is reversed. Further, GY _F and GY _B have substantially the same value. As a result, in the reverse turning steady phase, the direction of the actual lateral G (GY _A ) is opposite to that in the initial turning turning in FIG. That is, the direction of the actual lateral G (GY _A ) (that is, the direction of the trajectory angular rate) and the actual yaw rate (YAWR) are inconsistent during the reverse turning steady phase. Thereby, it can be correctly determined that the vehicle V is moving backward.

Conventionally, at the initial stage of reverse turning, as shown in FIG. 4A, there was no recognition that the actual yaw rate (YAWR) direction and the actual lateral G (GY _A ) direction coincided temporarily or not. As countermeasures against such an event, it is conceivable to adjust a threshold value for reverse determination or to provide a control delay for reverse determination. However, in the present embodiment, as described below, it is not a measure for adjusting a threshold value, nor a measure for providing a control delay, but a problem at the initial stage of reverse turning by another measure (reverse judgment is performed quickly and accurately). To solve.

≪Reverse determination device≫
Next, based on the above-described problems, the backward determination device 10 that is a characteristic part will be described with reference to FIG. Here, FIG. 5 is a functional block diagram showing a schematic function of the reverse determination device of FIG. FIG. 6A shows the relationship between the position of the lateral G sensor and the position of the center of gravity of the rear axis in the embodiment, and FIG. 6B shows the relationship between the position of the lateral G sensor and the position of the center of gravity of the vehicle in the comparative example. FIG.

  As shown in FIG. 1, the reverse determination device 10 is mounted on the ECU 1. As shown in FIG. 5, the reverse determination device 10 includes a rear-axis lateral G calculation unit 11 that calculates a rear-axis lateral G using the actual lateral G detected by the lateral G sensor SY as a functional block, and a rear-axis lateral G. And the vehicle body speed detected by the vehicle speed sensor SV, the trajectory angular rate calculation unit 12 that calculates the trajectory angular rate, whether the vehicle V is moving backward using the trajectory angular rate and the actual yaw rate detected by the yaw rate sensor SY. A reverse determination unit 13 that determines whether or not and outputs a determination result is provided. These are implemented as software, but may be implemented in the ECU 1 as hardware, such as an ASIC (Application Specific Integrated Circuit) that is an integrated circuit for a specific application.

(Calculation of rear axle lateral G)
When the lateral G sensor SG is placed at the rear axis gravity center position B, the detection value of the lateral G sensor SG indicates the lateral G at the rear axis gravity center position B as it is. However, normally, the lateral G sensor SG is not placed at such a position. For example, the lateral G sensor SG is generally placed at a lateral G sensor position indicated by a symbol D in FIGS.

In general, as shown in FIG. 6B, the detection value (GY _D ) of the lateral G sensor SG placed at the lateral G sensor position D is the actual lateral G (GY _A ) at the vehicle gravity center position _A. ) Is calculated (estimated). Here, in FIG. 6B, “LX _A ” is the distance in the front-rear direction from the center line in the front-rear direction of the vehicle V to the lateral G sensor position D. “LY _A ” is a distance in the left-right direction from the center line in the left-right direction of the vehicle V to the lateral G sensor position D. “YAWR” is an actual yaw rate.

In general, from the detection value of the lateral G sensor SG placed at the lateral G sensor position D, the actual lateral G (GY _A ) at the vehicle gravity center position A is calculated by the following equation 1.
_{GY A = GY D - LX A} × (d / dt) YAWR + LY A × YAWR ^ 2 ... ( Equation 1)

However, in the actual lateral G (GY _A ) at the vehicle center of gravity position A as described above, inconvenience occurs at the initial stage of reverse turning.

  Therefore, in the present embodiment, as shown in FIG. 4A, the actual lateral G at the rear wheel center of gravity position B that is the trajectory angular rate (actual lateral G) in the same direction as the actual yaw rate from the initial stage of reverse turning is calculated (estimated). )I decided to.

Specifically, in the present embodiment, as shown in FIG. 6A, the detected value (GY _D ) of the lateral G sensor SG placed at the lateral G sensor position D is the actual lateral position at the rear-axis center of gravity position B. Calculated (estimated) as G (GY _B ). Here, in FIG. 6A, “LX _B ” is the distance in the front-rear direction from the axis of the rear axis of the vehicle V to the lateral G sensor position D. “LY _B ” is a distance in the left-right direction from the center line in the left-right direction of the vehicle V to the lateral G sensor position D. “YAWR” is an actual yaw rate. If the lateral G sensor position D is the same, “LY _B ” in FIG. 6A and “LY _A ” in FIG. 6B have the same value.

That is, the rear lateral G calculation unit 11 shown in FIG. 5 calculates the actual lateral G (GY at the rear axial center of gravity B from the detection value of the lateral G sensor SG placed at the lateral G sensor position D by the following equation 2. _A ) is calculated.
_{GY B = GY D - LX B} × (d / dt) YAWR + LY B × YAWR ^ 2 ... ( Equation 2)

(Calculation of locus angle rate)
The actual lateral G at the calculated rear-axis center-of-gravity position B is output to the locus angle rate calculation unit 12.
The trajectory angle rate calculation unit 12 shown in FIG. 5 calculates the trajectory angle rate by the following equation (Equation 3) using the calculated actual lateral G (GY _B ) and the vehicle body speed from the vehicle body speed sensor SV. . The locus angle rate is also referred to as a revolution yaw rate.
Trajectory angle rate = actual lateral G / vehicle speed (Formula 3)

  The merits of converting the actual horizontal to the trajectory angular rate will be described. Originally, the dimensions are different between the yaw rate (rad / s) and the horizontal G (N). However, by converting the actual lateral G into the trajectory angular rate (rad / s), the dimension matches the yaw rate (deg / s), so that the comparison becomes easy.

(Reverse judgment)
The calculated trajectory angle rate is output to the trajectory angle rate calculation unit 12.
The reverse determination unit 13 shown in FIG. 5 compares the calculated trajectory angle rate with the actual yaw rate from the yaw rate sensor SY, and determines that the two are in the forward direction and the two are in the reverse direction if they are in the same direction. Then, the determination result is output to another functional block of the ECU 1.

≪Operation explanation≫
FIG. 7 is a flowchart showing the determination operation by the reverse determination device. The operation of the reverse determination device will be described with reference to this flowchart. The operating subject is the reverse determination device 10, and the reverse determination device 10 executes each step (each step) in FIG.

First, in step S1, the reverse determination device 10 acquires the actual lateral G (GY _D ) from the lateral G sensor SG, acquires the vehicle speed from the vehicle speed sensor SV, and the actual yaw rate (YAWR) from the yaw rate sensor SY. ) To get. The actual lateral G at this time is a value at the lateral G sensor position D.

Next, in step S2, the rear-axis lateral G calculation unit 11 calculates (estimates) the actual lateral G (GY _B ) at the rear-axis center-of-gravity position B using Equation 2 from the actual lateral G and the actual yaw rate acquired in step S1. To do. In step S3, the trajectory angular rate calculation unit 12 calculates the trajectory angular rate using Equation 3 from the actual lateral G at the rear wheel center of gravity position B calculated in step S2 and the vehicle body speed acquired in step S1.

  In step S4, the reverse determination unit 13 compares the trajectory angle rate calculated in step S3 with the actual yaw rate acquired in step S1 (compare directions). As a result of the comparison, if both directions are the same (S5 → Yes), the reverse determination unit 13 determines that the vehicle is moving forward and outputs the result (S6). On the other hand, as a result of the comparison, if the two directions are different (S5 → No), the reverse determination unit 13 determines the reverse and outputs the result (S7).

  When the reverse determination device 10 outputs a determination that the vehicle V is moving backward, the ECU 1 prohibits the side slip suppression control by the VSA as described above until it is determined that the vehicle is moving forward. As a result, the passenger does not feel uncomfortable. That is, in the case of the comparative example of FIG. 6B, as shown in FIG. 3, it is determined that the vehicle is moving forward in the early stage of reverse turning, and the ECU 1 executes the side slip suppression control. Then, this is solved. Moreover, it is estimated that the vehicle is moving forward in a situation where it cannot be determined that the vehicle is moving backward, so that the ECU 1 executes side slip suppression control. That is, according to the present embodiment, the backward determination can be performed quickly and accurately.

FIG. 8 is an explanatory diagram of the effect of the reverse determination device 10. FIG. 8 shows time on the horizontal axis and the actual yaw rate / trajectory angle rate on the vertical axis, as in FIG.
As shown in FIG. 8, the trajectory angular rate of the comparative example, that is, the trajectory angular rate using the actual lateral G at the center of gravity A of the vehicle, although the vehicle V is retreating at the beginning of reverse turning. In the same direction as the actual yaw rate. On the other hand, the trajectory angle rate of the embodiment using the actual lateral G at the rear-axis center-of-gravity position B does not coincide with the actual yaw rate even in the initial stage of reverse turning, so that the reverse determination can be performed quickly and accurately. Can be done.

≪Summary≫
The embodiment described above shows an example in carrying out the present invention, and it goes without saying that the present invention is not construed as being limited to the above-described embodiment. Further, in the embodiment, a vehicle equipped with an engine has been described, but the present invention can also be applied to an electric vehicle, a hybrid vehicle, a fuel cell vehicle, and the like. Further, although the embodiment has been described based on the VSA that controls the behavior of the vehicle by controlling the braking force (generates the yaw moment), the present invention controls the driving force (the distribution of the driving force). Therefore, the present invention can be applied to a system capable of controlling the behavior of the vehicle, for example, SH-AWD (Super Handling All-Wheel-Drive) of the present applicant. Moreover, although the example which compares an actual yaw rate and a locus | trajectory angle rate was shown, you may make it compare an actual yaw rate and the actual horizontal G in the rear-axis gravity center position B. FIG. Needless to say, these also belong to the technical scope of the present invention.
In the present embodiment, an example is shown in which the trajectory angular rate obtained by dividing the lateral acceleration (actual lateral G) by the vehicle speed is used in order to facilitate the comparison by matching the dimensions of the physical quantities, but the present invention is not limited to this. Instead, it is needless to say that the lateral acceleration and the yaw rate on the rear axis may be compared directly or after being multiplied or divided by a predetermined constant or the like in consideration of the difference in dimensions.

V Vehicle 1 ECU
DESCRIPTION OF SYMBOLS 10 Reverse determination apparatus 11 Rear-axis lateral G calculation part 12 Trajectory angle rate calculation part 13 Reverse determination part SG Lateral G sensor SV Vehicle speed sensor SY Yaw rate sensor A Vehicle center-of-gravity position B Rear-axis center-of-gravity position

Claims (4)

A lateral acceleration applied to the vehicles, on the basis of the yaw rate of the vehicle, a retraction device for judging the backward movement of the vehicle,
A rear-axis lateral acceleration calculation unit that calculates a rear-axis lateral acceleration that is a lateral acceleration on the rear axle of the vehicle based on the lateral acceleration detected by the lateral acceleration detection unit;
A reverse determination device comprising: a reverse determination unit that compares the rear-axis lateral acceleration and the yaw rate detected by a yaw rate sensor to determine the reverse of the vehicle. A reverse determination device that determines the reverse of a vehicle based on a vehicle body speed, a lateral acceleration applied to the vehicle, and a vehicle yaw rate,
A rear-axis lateral acceleration calculation unit that calculates a rear-axis lateral acceleration that is a lateral acceleration on the rear axle of the vehicle based on the lateral acceleration detected by the lateral acceleration detection unit;
A trajectory angle rate calculation unit that calculates a trajectory angle rate of the vehicle based on the rear-axis lateral acceleration and the vehicle body speed detected by the vehicle body speed detection unit;
A reverse determination device comprising: a reverse determination unit that compares the trajectory angular rate with the yaw rate detected by a yaw rate sensor and determines reverse of the vehicle. The vehicle includes a behavior control device that generates a yaw moment in a vehicle body by applying a braking force to at least one wheel.
The reverse according to claim 1 or 2, wherein when the reverse determination unit determines the reverse of the vehicle, the generation of the yaw moment by the behavior control device is stopped in cooperation with the behavior control device. Judgment device. A reverse determination device that inputs the vehicle body speed detected by the vehicle body speed detection means, the lateral acceleration applied to the vehicle detected by the lateral acceleration detection means, and the vehicle yaw rate detected by the yaw rate sensor, determines the reverse of the vehicle. A determination method comprising:
Obtaining the vehicle body speed;
Obtaining the lateral acceleration;
Obtaining the yaw rate;
Calculating a rear-axis lateral acceleration that is an acceleration on a rear axle of the vehicle based on the lateral acceleration and the yaw rate ;
Calculating a trajectory angular rate of the vehicle based on the rear-axis lateral acceleration and the vehicle body speed;
And a step of comparing the trajectory angle rate and the yaw rate to determine the reverse of the vehicle.

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