JP2016147522A - Vehicle behavior control device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a vehicle behavior control device capable of accurately detecting a wiper-like behavior.SOLUTION: In wiper-like behavior determination processing according to an embodiment of the present invention, a vehicle behavior control device 1 determines whether or not a wiper-like behavior is generated in a vehicle on the basis of a change of air pressure in each wheels detected by an air pressure sensor 2e, when the vehicle is determined as in a halt state and in an uphill state. In this way, the wiper-like behavior can be accurately detected.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a vehicle behavior control device that determines whether or not a wiper behavior has occurred in a vehicle and controls the behavior of the vehicle based on the determination result.

  2. Description of the Related Art Conventionally, there is known a vehicle behavior control device that determines whether or not a wiper behavior has occurred in a vehicle based on the angular velocity of the vehicle detected by a yaw rate sensor and controls the behavior of the vehicle based on the determination result. Here, the wiper behavior means a vehicle behavior in which the vehicle rotates when a side slip occurs on a wheel on which a load is missing on a slope.

JP 2007-237910 A

  When the vehicle travels at a low speed, the detection accuracy of the angular velocity of the vehicle by the yaw rate sensor is low, so that there is a possibility that the wiper behavior cannot be detected accurately. Specifically, when the vehicle travels at a low speed, the angular velocity detected by the yaw rate sensor is about 2 deg / s, whereas the angular velocity of the vehicle when the wiper behavior occurs is about 1 deg / s. The behavior may not be detected accurately.

  The present invention has been made in view of the above problems, and an object thereof is to provide a vehicle behavior control device capable of accurately detecting a wiper behavior.

  A vehicle behavior control device according to the present invention is a vehicle behavior control device that determines whether or not a wiper behavior has occurred in a vehicle and controls the behavior of the vehicle based on the determination result, and whether or not the vehicle is stopped. Stop determining means for determining whether the vehicle is traveling on an uphill, air pressure detecting means for detecting the air pressure of each wheel of the vehicle, and the stop determining means are the vehicle Is determined to be stopped, and when the uphill determination means determines that the vehicle is traveling uphill, based on the change in the air pressure of each wheel detected by the air pressure detection means, And a wiper behavior determining means for determining whether or not a wiper behavior is occurring in the vehicle.

  According to the vehicle behavior control device of the present invention, when the vehicle is stopped and traveling on an uphill, whether or not a wiper behavior is generated in the vehicle based on a change in air pressure of each wheel of the vehicle. Therefore, the wiper behavior can be detected with high accuracy.

FIG. 1 is a block diagram showing a configuration of a vehicle behavior control apparatus according to an embodiment of the present invention. FIG. 2 is a flowchart showing the flow of the wiper behavior determination process according to the embodiment of the present invention. FIG. 3 is a flowchart showing a flow of a modification of the wiper behavior determination process according to the embodiment of the present invention.

  Hereinafter, the configuration and operation of a vehicle behavior control apparatus according to an embodiment of the present invention will be described with reference to the drawings.

[Configuration of vehicle behavior control device]
First, with reference to FIG. 1, the structure of the vehicle behavior control apparatus which is one Embodiment of this invention is demonstrated.

  FIG. 1 is a block diagram showing a configuration of a vehicle behavior control apparatus according to an embodiment of the present invention. As shown in FIG. 1, a vehicle behavior control device 1 according to an embodiment of the present invention is configured by an information processing device such as an ECU (Electronic Control Unit) and is mounted on a vehicle. The vehicle behavior control device 1 functions under the control of the CPU by loading an application program held in the ROM of the information processing device into the RAM of the information processing device and executing it by the CPU of the information processing device. This is realized by operating the controlled object and reading and writing data in the RAM or ROM.

  The vehicle behavior control device 1 includes a yaw rate sensor 2a, a wheel speed sensor 2b, a ground load sensor 2c, a stroke sensor 2d, and an air pressure sensor 2e.

  The yaw rate sensor 2a detects the angular velocity (yaw rate) of the vehicle and outputs an electric signal indicating the detected angular velocity to the vehicle behavior control device 1.

  The wheel speed sensor 2 b detects the rotational speed of each wheel of the vehicle and outputs an electrical signal indicating the detected rotational speed to the vehicle behavior control device 1.

  The ground load sensor 2 c detects the ground load of each wheel of the vehicle, and outputs an electric signal indicating the detected ground load to the vehicle behavior control device 1.

  The stroke sensor 2d detects a stroke amount of a suspension provided on each wheel of the vehicle, and outputs an electric signal indicating the detected stroke amount to the vehicle behavior control device 1.

  The air pressure sensor 2e detects the air pressure of each wheel of the vehicle, and outputs an electric signal indicating the detected air pressure to the vehicle behavior control device 1.

  The vehicle behavior control device 1 having such a configuration determines whether or not a wiper behavior has occurred in the vehicle based on an output signal from each sensor by executing the following wiper behavior determination process. When the wiper behavior occurs, the behavior of the vehicle is controlled by controlling the braking device 3. Hereinafter, with reference to the flowchart shown in FIG. 2, the operation of the vehicle behavior control apparatus 1 when executing the wiper behavior determination process according to the embodiment of the present invention will be described.

[Wiper behavior judgment processing]
FIG. 2 is a flowchart showing the flow of the wiper behavior determination process according to the embodiment of the present invention. The flowchart shown in FIG. 2 starts at the timing when the ignition switch of the vehicle is switched from the off state to the on state, and the wiper behavior determination process proceeds to step S1. The wiper behavior determination process is repeatedly executed every predetermined control period while the ignition switch of the vehicle is in the ON state.

  In the process of step S1, the vehicle behavior control device 1 determines whether or not the absolute value of the angular velocity (yaw rate) Yr of the vehicle is greater than or equal to a predetermined value based on the output signal of the yaw rate sensor 2a. As a result of the determination, if the absolute value of the yaw rate Yr is not equal to or greater than the predetermined value (step S1: No), the vehicle behavior control device 1 advances the wiper behavior determination process to the process of step S2. On the other hand, when the absolute value of the yaw rate Yr is greater than or equal to the predetermined value (step S1: Yes), the vehicle behavior control device 1 advances the wiper behavior determination process to the process of step S8.

  In the process of step S2, the vehicle behavior control device 1 determines whether or not the vehicle is stopped based on the output signal of the wheel speed sensor 2b. If the result of determination is that the vehicle is not in a stopped state (step S2: No), the vehicle behavior control device 1 advances the wiper behavior determination process to the process of step S7. On the other hand, when the vehicle is in a stopped state (step S2: Yes), the vehicle behavior control device 1 advances the wiper behavior determination process to the process of step S3.

  In the process of step S3, the vehicle behavior control device 1 calculates the difference (ground load difference) Gx between the ground load of the front wheel and the ground load of the rear wheel based on the output signal of the ground load sensor 2c. It is determined whether or not the vehicle is in an uphill state (a state where the vehicle is traveling on an uphill) by determining whether or not the ground contact load difference Gx is less than a predetermined value. If the contact load difference Gx is not less than the predetermined value as a result of the determination (step S3: No), the vehicle behavior control device 1 determines that the vehicle is not in an uphill state, and advances the wiper behavior determination process to the process of step S7. On the other hand, when the contact load difference Gx is less than the predetermined value (step S3: Yes), the vehicle behavior control device 1 determines that the vehicle is in an uphill state (determination A is established), and performs a wiper behavior determination process. The process proceeds to S4.

  In the process of step S4, the vehicle behavior control device 1 determines whether or not the temporal change amount of the ground load of the left and right wheels of the vehicle satisfies a predetermined condition based on the output signal of the ground load sensor 2c. An example of the predetermined condition is that the time variation dFfl / dt of the contact load of the left wheel is positive and the time variation dFfr / dt of the contact load of the right wheel is negative. As a result of the determination, when the temporal change amount of the ground load of the left and right wheels does not satisfy the predetermined condition (step S4: No), the vehicle behavior control device 1 advances the wiper behavior determination process to the process of step S5. On the other hand, when the temporal change amount of the ground load of the left and right wheels satisfies the predetermined condition (step S4: Yes), the vehicle behavior control device 1 determines that the determination B is satisfied, and the wiper behavior determination process The process proceeds to step S8.

  In the process of step S5, the vehicle behavior control device 1 determines whether or not the time variation of the suspension stroke amount (suspension stroke) of the left and right wheels of the vehicle satisfies a predetermined condition based on the output signal of the stroke sensor 2d. Is determined. An example of the predetermined condition is that the time variation dSfl / dt of the left wheel suspension stroke is positive and the time variation dSfr / dt of the right wheel suspension stroke is negative. As a result of the determination, if the time change amount of the left and right wheel suspension strokes does not satisfy the predetermined condition (step S5: No), the vehicle behavior control device 1 advances the wiper behavior determination process to the process of step S6. On the other hand, when the time change amount of the suspension stroke of the left and right wheels satisfies the predetermined condition (step S5: Yes), the vehicle behavior control device 1 determines that the determination C is satisfied, and performs the wiper behavior determination process. The process proceeds to step S8.

  In the process of step S6, the vehicle behavior control device 1 determines whether or not the time change rate of the air pressure of each wheel of the vehicle satisfies a predetermined condition based on the output signal of the air pressure sensor 2e. Examples of the predetermined condition include the following conditions (1) and (2).

Condition (1) (clockwise wiper behavior): The time change rate of the air pressure of the right front wheel (FR wheel) of the vehicle is positive, or the time change rate of the air pressure of the right rear wheel (RR) of the vehicle is positive, In addition, the time change rate of the air pressure of the left front wheel (FL wheel) of the vehicle is negative, or the time change rate of the air pressure of the left rear wheel (RL) of the vehicle is negative.

Condition (2) (counterclockwise wiper behavior): the time change rate of the air pressure of the left front wheel (FL wheel) of the vehicle is positive, or the time change rate of the air pressure of the left rear wheel (RL) of the vehicle is positive, In addition, the time change rate of the air pressure of the right front wheel (FR wheel) of the vehicle is negative, or the time change rate of the air pressure of the right rear wheel (RR) of the vehicle is negative.

  As a result of the determination, if the time change rate of the air pressure of each wheel of the vehicle does not satisfy the predetermined condition (step S6: No), the vehicle behavior control device 1 advances the wiper behavior determination process to the process of step S7. On the other hand, when the time change rate of the air pressure of each wheel of the vehicle satisfies the predetermined condition (step S6: Yes), the vehicle behavior control device 1 determines that the determination D is satisfied, and the wiper behavior determination process. The process proceeds to step S8.

  In the process of step S7, the vehicle behavior control device 1 determines that no wiper behavior has occurred in the vehicle. Thereby, the process of step S7 is completed and a series of wiper behavior determination processes are complete | finished.

  In the process of step S8, the vehicle behavior control device 1 determines that the wiper behavior is occurring in the vehicle. Thereby, the process of step S8 is completed, and the wiper behavior determination process proceeds to the process of step S9.

  In the process of step S <b> 9, the vehicle behavior control device 1 controls the braking device 3 to reduce the wheel cylinder pressure (W / C pressure) of each wheel of the vehicle. Specifically, the vehicle behavior control device 1 reduces the wheel cylinder pressure of the Fr system because the lateral force is lost for the Fr system. On the other hand, for the Rr system, the vehicle behavior control apparatus 1 steers the rear steer toward the counter steer side and reduces the Rr system wheel cylinder pressure. Thereby, the process of step S9 is completed and a series of wiper behavior determination processes are complete | finished.

  As is clear from the above description, according to the wiper behavior determination process according to an embodiment of the present invention, the vehicle behavior control device 1 determines that the vehicle is in a stopped state and in an uphill state. Based on the change in the air pressure of each wheel detected by the air pressure sensor 2e, it is determined whether or not a wiper behavior has occurred in the vehicle. Thereby, the wiper behavior can be detected with high accuracy.

[Modification]
Finally, with reference to FIG. 3, a modified example of the wiper behavior determination process according to an embodiment of the present invention will be described. According to the modification example of the wiper behavior determination process according to the embodiment of the present invention, the wiper behavior can be detected with higher accuracy.

  FIG. 3 is a flowchart showing a flow of a modification of the wiper behavior determination process according to the embodiment of the present invention. The flowchart shown in FIG. 3 starts at the timing when the ignition switch of the vehicle is switched from the off state to the on state, and the wiper behavior determination process proceeds to step S11. The wiper behavior determination process is repeatedly executed every predetermined control period while the ignition switch of the vehicle is in the ON state.

  In the process of step S11, the vehicle behavior control device 1 determines whether any of the above determinations B, C, D is established. If none of the determinations B, C, and D is established as a result of determination (step S11: No), the vehicle behavior control device 1 advances the wiper behavior determination process to the process of step S14. On the other hand, when any one of the determinations B, C, and D is established (step S11: Yes), the vehicle behavior control device 1 advances the wiper behavior determination process to the process of step 12.

  In the process of step S12, the vehicle behavior control device 1 drives the rear steer to the counter steer side based on the output signal of the yaw rate sensor 2a. Thereby, the process of step S12 is completed and the wiper behavior determination process proceeds to the process of step S13.

  In the process of step S13, the vehicle behavior control device 1 determines whether or not the amount of change in yaw rate tends to decrease based on the output signal of the yaw rate sensor 2a. As a result of the determination, when the change amount of the yaw rate does not tend to decrease (step S13: No), the vehicle behavior control device 1 advances the wiper behavior determination process to the process of step S14. On the other hand, when the change amount of the yaw rate tends to decrease (step S13: Yes), the vehicle behavior control device 1 determines that the determination E is established, and advances the wiper behavior determination processing to the processing of step S15.

  In the process of step S14, the vehicle behavior control device 1 determines that no wiper behavior has occurred in the vehicle. Thereby, the process of step S14 is completed and a series of wiper behavior determination processes are complete | finished.

  In the process of step S15, the vehicle behavior control device 1 determines that the wiper behavior is occurring in the vehicle. Thereby, the process of step S15 is completed and the wiper behavior determination process proceeds to the process of step S16.

  In the process of step S <b> 16, the vehicle behavior control device 1 controls the braking device 3 to reduce the wheel cylinder pressure (W / C pressure) of each wheel of the vehicle. Specifically, the vehicle behavior control device 1 reduces the wheel cylinder pressure of the Fr system because the lateral force is lost for the Fr system. On the other hand, for the Rr system, the vehicle behavior control apparatus 1 steers the rear steer toward the counter steer side and reduces the Rr system wheel cylinder pressure. Thereby, the process of step S16 is completed and a series of wiper behavior determination processes are complete | finished.

  As mentioned above, although the embodiment to which the invention made by the present inventors was applied has been described, the present invention is not limited by the description and the drawings that constitute a part of the disclosure of the present invention according to this embodiment. That is, other embodiments, examples, operation techniques, and the like made by those skilled in the art based on this embodiment are all included in the scope of the present invention.

DESCRIPTION OF SYMBOLS 1 Vehicle behavior control apparatus 2a Yaw rate sensor 2b Wheel speed sensor 2c Ground load sensor 2d Stroke sensor 2e Air pressure sensor 3 Braking device

Claims (1)

A vehicle behavior control device that determines whether or not a wiper behavior has occurred in a vehicle, and controls the behavior of the vehicle based on the determination result,
Stop determination means for determining whether or not the vehicle is stopped;
An uphill judging means for judging whether or not the vehicle is traveling uphill;
Air pressure detecting means for detecting the air pressure of each wheel of the vehicle;
When the stop determination means determines that the vehicle is stopped, and the uphill determination means determines that the vehicle is traveling on an uphill, each wheel detected by the air pressure detection means A wiper behavior determination means for determining whether or not a wiper behavior has occurred in the vehicle based on a change in air pressure;
A vehicle behavior control device comprising:

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