JP2012076702A - Information processing apparatus for vehicle and vehicle control system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an information processing apparatus for vehicle, which can accurately determine the behavior of the vehicle due to the skid of wheels; and to provide a vehicle control system.SOLUTION: The information processing apparatus 1 for vehicle is provided which determines the behavior of the vehicle due to the skid of the wheels of the vehicle based on the direction of yaw rate detected by a yaw rate-detection unit 38 for detecting a yaw rate of the vehicle 100, and also the vehicle control system 1-1 is provided which includes the information processing apparatus 1. The information processing apparatus determines that the behavior occurs when the direction of the yaw rate does not change for a predetermined time period.

Description

  The present invention relates to a vehicle information processing device and a vehicle control device.

  Conventionally, a technique for detecting a change in posture of a vehicle has been proposed. Patent Document 1 discloses a technique of a vehicle control device that detects a change in posture of a vehicle that slides down a slope from a comparison result between a vehicle angular velocity detected by a yaw rate sensor and a posture change detection threshold value.

  Patent Document 2 discloses a vehicle control device that, when detecting a change in the posture of a vehicle sliding down a slope, releases the holding of the braking state by the brake holding control, and further rotates the steering wheel in the steering direction to return the vehicle to the posture before the change. The technology is disclosed.

JP 2007-237910 A JP 2007-237908 A

  It is desired to be able to improve the determination accuracy with respect to vehicle behavior due to wheel slip. For example, when trying to determine a small behavior of a vehicle, the behavior to be captured may not be accurately determined depending on the detection accuracy of the sensor.

  An object of the present invention is to provide a vehicle information processing device and a vehicle control device that can accurately determine the behavior of a vehicle due to wheel slip.

  An information processing apparatus for a vehicle according to the present invention is characterized in that the behavior of the vehicle due to slipping of a wheel of the vehicle is determined based on a direction of the yaw rate detected by a yaw rate detection unit that detects a yaw rate of the vehicle. .

  In the vehicle information processing apparatus, it is preferable to determine that the behavior occurs when the direction of the yaw rate does not change for a predetermined time.

  In the vehicle information processing apparatus, it is preferable that the predetermined time is determined based on a natural frequency of the vehicle.

  In the vehicle information processing apparatus, it is preferable to determine that the behavior occurs when the magnitude of the yaw rate continues to increase.

  In the vehicle information processing apparatus, it is preferable to determine that the behavior occurs when a change of a predetermined degree or more is detected in the yaw rate.

  In the vehicle information processing apparatus, it is preferable that the behavior is determined when the vehicle is stopped.

  In the vehicular information processing apparatus, it is preferable that the behavior determination is performed when the vehicle is controlled to maintain a braking force capable of maintaining a stopped state.

  The vehicle control device according to the present invention preferably includes the vehicle information processing device, and ends the holding of the braking force when it is determined that the behavior occurs.

  The vehicle information processing apparatus according to the present invention determines the behavior of the vehicle due to slipping of the wheels of the vehicle based on the direction of the yaw rate detected by the yaw rate detection unit that detects the yaw rate of the vehicle. Therefore, according to the vehicle information processing apparatus of the present invention, it is possible to accurately determine the behavior of the vehicle due to wheel slip.

FIG. 1 is a flowchart illustrating a determination method of the vehicle information processing apparatus according to the embodiment. FIG. 2 is a diagram illustrating a vehicle on which the vehicle information processing device and the vehicle control device of the embodiment are mounted. FIG. 3 is a diagram illustrating the wiper behavior. FIG. 4 is a diagram illustrating the rolling of the vehicle. FIG. 5 is a diagram illustrating an example of the yaw rate detected by the yaw rate sensor.

  Hereinafter, a vehicle information processing device and a vehicle control device according to an embodiment of the present invention will be described in detail with reference to the drawings. In addition, this invention is not limited by this embodiment. In addition, constituent elements in the following embodiments include those that can be easily assumed by those skilled in the art or those that are substantially the same.

(Embodiment)
The embodiment will be described with reference to FIGS. 1 to 5. The present embodiment relates to a vehicle information processing device and a vehicle control device. FIG. 1 is a flowchart illustrating a determination method for a vehicle information processing device according to the present embodiment, FIG. 2 is a diagram illustrating a vehicle on which the vehicle information processing device and the vehicle control device of the present embodiment are mounted, and FIG. It is a figure which shows a wiper behavior.

  In the present embodiment, a phenomenon in which the vehicle skids on a slope or the like is described as a wiper behavior. Although the wiper behavior can be determined based on the magnitude of the yaw rate detected by the yaw rate sensor, it cannot be accurately determined until the behavior becomes large to some extent. The yaw rate due to the wiper behavior is, for example, about 1 deg / s. On the other hand, if the variation in the design value of the yaw rate sensor is, for example, about 4 deg / s, it is large to capture the wiper behavior during stoppage. Because it is too much, it cannot be used as it is.

  In the present embodiment, a behavior higher than the accuracy of the yaw rate sensor is captured based on the change amount of the yaw rate. As will be described below, in the present embodiment, in order to catch the start of the wiper behavior, a pre-determination is performed based on the change rate of the yaw rate after the vehicle stop determination. Since the wiper behavior is skidding and the yaw rate (see symbol C1 in FIG. 5) can only swing in one direction, the behavior of the yaw rate is further monitored after the pre-determination (time t2 in FIG. 5). If the yaw rate changes in the same direction as before the pre-determination after the pre-determination, the determination of the occurrence of the wiper behavior is confirmed. According to the determination of the wiper behavior of the present embodiment, the wiper behavior can be determined even if the detected yaw rate is a value within the variation range of the yaw rate sensor.

  As shown in FIG. 2, the vehicle 100 includes a vehicle control device 1-1. The vehicle control device 1-1 includes a braking control device 1 that performs braking control of the vehicle 100 and a drive control device 2 that performs driving control of the vehicle 100. The braking control device 1 generates a braking force on each wheel of the vehicle 100. The vehicle 100 includes a brake pedal 20, braking force generation means 41FR, 41FL, 41RR, 41RL, braking force generation means side brake fluid piping 42FL, 42FR, 42RL, 42RR, a brake booster 43, a master cylinder 44, and a brake actuator as braking devices. 50. In the present embodiment, subscript FL is a left front wheel of vehicle 100, FR is a right front wheel of vehicle 100, RL is a left rear wheel of vehicle 100, and RR is a component related to a right rear wheel of vehicle 100, respectively. Show.

  The braking force that the braking control device 1 generates on each wheel is a mechanical braking force, specifically, a braking force that uses a frictional force. The braking control device 1 applies a mechanical wheel braking torque due to friction to each wheel by the pressure of the brake fluid as a working fluid (hereinafter also simply referred to as “hydraulic pressure” or “brake hydraulic pressure”). Generate wheel braking force on the wheels. The vehicle 100 is braked by the wheel braking force.

  The braking force generating means 41FL, 41FR, 41RL, 41RR are mechanical and frictional braking means, for example, generating a braking force (friction braking force) by a frictional force generated between a brake pad and a disc rotor. A friction braking device. The braking force generation means 41FL, 41FR, 41RL, 41RR generate a braking force that brakes the vehicle 100 by the hydraulic pressure of the supplied working fluid.

  The brake booster 43 increases the pedal effort input to the brake pedal 20 by the driver. Here, the brake pedal 20 includes a pedal arm 20A that transmits the driver's pedaling force to the master cylinder 44 via the brake booster 43, and a pedal body 20P that is attached to the pedal arm 20A and transmits the driver's pedaling force to the pedal arm 20A. Have The driver's pedaling force is a force for generating a wheel braking force on each wheel. The master cylinder 44 converts the pedal effort increased by the brake booster 43 into brake hydraulic pressure. The brake actuator 50 transmits the converted brake fluid pressure to the respective brake force generation means side brake fluid pipes 42FL, 42FR, 42RL, 42RR as it is or after adjustment.

  The brake actuator 50 and the respective braking force generation means 41FL, 41FR, 41RL, 41RR are connected by a braking force generation means side brake fluid piping 42FL, 42FR, 42RL, 42RR. The brake actuator 50 and the master cylinder 44 are connected by a master cylinder side first brake fluid pipe 45A and a master cylinder side second brake fluid pipe 45B.

  Brake fluid passage provided in the master cylinder 44, braking force generating means side brake fluid piping 42FL, 42FR, 42RL, 42RR, master cylinder side first brake fluid piping 45A, master cylinder side second brake fluid piping 45B, and brake actuator 50 Is filled with brake fluid.

  In the present embodiment, the brake actuator 50 has a function of individually adjusting the brake fluid pressures of the respective brake force generation means side brake fluid pipes 42FL, 42FR, 42RL, and 42RR. The brake actuator 50 can generate a wheel braking force having an independent magnitude for each wheel. When the brake control device 1 controls the drive of the brake actuator 50, so-called ABS control, brake assist control, hill start assist control, and the like are performed.

  The operation of the brake actuator 50 is controlled by the braking control device 1 to generate a wheel braking force corresponding to a target vehicle braking force (target vehicle braking force) on each wheel. The braking control device 1 is configured by combining a microcomputer, a memory, and the like, for example, and controls the wheel braking force for each wheel. The brake control device 1 includes a master cylinder pressure sensor 31, a stroke sensor 32, and a pedaling force detection as means for detecting the operation state of the brake, that is, the operation state of the brake pedal 20 by the driver of the vehicle 100 (brake operation detection means). A switch 33 is connected. The vehicle braking device 1-1 includes at least one brake operation detection unit.

  The brake actuator 50 includes a first hydraulic pressure transmission system 51A that transmits the brake hydraulic pressure from the master cylinder 44 to the braking force generation means 41FR and 41RL, and a second hydraulic pressure transmission system 51B that transmits the braking force generation means 41FL and 41RR. With. The first hydraulic pressure transmission system 51A is connected to the master cylinder 44 by a master cylinder side first brake fluid piping 45A, and the second hydraulic pressure transmission system 51B is connected to the master cylinder 44 by a master cylinder side second brake fluid piping 45B. Is done.

  In the first hydraulic pressure transmission system 51A, the brake hydraulic pressure from the master cylinder 44 includes the master cylinder side first brake fluid piping 45A, the first master cut valve 52A that is a flow control valve, and the first high pressure brake that is a brake fluid passage. This is transmitted to the braking force generating means 41FR and 41RL via the liquid pipe 58A and the holding solenoid valves 53FR and 53RL. Pressure reducing solenoid valves 54FR and 54RL are connected between the holding solenoid valves 53FR and 53RL and the braking force generating means 41FR and 41RL.

  By operating the holding solenoid valves 53FR and 53RL and the pressure reducing solenoid valves 54FR and 54RL, the brake fluid pressure acting on the braking force generating means 41FR and 41RL is increased or decreased, and the braking forces of the right front wheel and the left rear wheel are adjusted respectively. The For example, the brake fluid pressure acting on the braking force generating means 41FR and 41RL is increased or decreased by changing the duty ratio between the opening time and the closing time of the holding solenoid valves 53FR and 53RL and the pressure reducing solenoid valves 54FR and 54RL.

  In the second hydraulic pressure transmission system 51B, the brake hydraulic pressure from the master cylinder 44 includes the master cylinder side second brake fluid piping 45B, the second master cut valve 52B which is a flow control valve, and the second high pressure brake which is a brake fluid passage. This is transmitted to the braking force generating means 41FL, 41RR via the liquid pipe 58B and the holding solenoid valves 53FL, 53RR. Pressure reducing solenoid valves 54FL and 54RR are connected between the holding solenoid valves 53FL and 53RR and the braking force generating means 41FL and 41RR.

  By operating the holding solenoid valves 53FL, 53RR and the pressure reducing solenoid valves 54FL, 54RR, the brake fluid pressure acting on the braking force generating means 41FL, 41RR is increased or decreased, and the braking forces of the left front wheel and the right rear wheel are adjusted respectively. The For example, by changing the duty ratio between the opening time and the closing time of the holding solenoid valves 53FL and 53RR and the pressure reducing solenoid valves 54FL and 54RR, the brake fluid pressure acting on the braking force generating means 41FL and 41RR is increased or decreased.

  The first master cut valve 52A and the second master cut valve 52B (hereinafter referred to as the master cut valve 52 as necessary), which are flow rate control valves, have linear solenoids and springs. The master cut valve 52 is a normally open electromagnetic flow control valve that is open when the solenoid is not energized and that can adjust the opening by adjusting the current supplied to the solenoid. The master cut valve 52 changes its opening degree linearly by using a linear solenoid. The master cut valve 52 adjusts the opening to create a differential pressure (master cut valve differential pressure) ΔP_SMC (= Pe−Pi) between the brake fluid pressure Pe at the outlet and the brake fluid pressure Pi at the inlet. The differential pressure ΔP_SMC can be changed linearly.

  Here, the brake fluid pressure on the outlet side of the first master cut valve 52A and the second master cut valve 52B is the brake fluid pressure inside the first high pressure brake fluid piping 58A and the second high pressure brake fluid piping 58B, respectively. The brake fluid pressure on the inlet side of the first master cut valve 52A and the second master cut valve 52B is the brake fluid pressure inside the master cylinder side first brake fluid piping 45A and the master cylinder side second brake fluid piping 45B, respectively. is there.

  The pressure on the inlet side of the first master cut valve 52A and the second master cut valve 52B is detected by the master cylinder pressure sensor 31 and acquired by the braking control device 1. Also, the brake fluid pressure inside the first high-pressure brake fluid piping 58A and the second high-pressure brake fluid piping 58B is detected by the first outlet-side brake fluid pressure sensor 36A and the second outlet-side brake fluid pressure sensor 36B attached thereto. And acquired by the braking control device 1. The master cut valve differential pressure can also be obtained from the control current supplied to the master cut valve 52.

  The outlets of the pressure reducing solenoid valves 54FR and 54RL and the master cylinder side first brake fluid piping 45A are respectively connected to the first brake fluid reservoir 57A. Further, the outlets of the pressure reducing solenoid valves 54FL and 54RR and the master cylinder side second brake fluid pipe 45B are respectively connected to the second brake fluid reservoir 57B.

  The brake actuator 50 includes a first pump 56A that pressurizes the brake fluid in the first hydraulic pressure transmission system 51A in order to adjust the hydraulic pressure of the first hydraulic pressure transmission system 51A, and the second hydraulic pressure transmission system 51B. In order to adjust the hydraulic pressure, a second pump 56B for pressurizing the brake fluid in the second hydraulic pressure transmission system 51B is provided. When the first pump 56A pressurizes the brake fluid in the first hydraulic pressure transmission system 51A, the pressure of the brake fluid applied to the braking force generating means 41FR and 41RL, that is, the hydraulic pressure increases. Similarly, when the second pump 56B pressurizes the brake fluid in the second hydraulic pressure transmission system 51B, the hydraulic pressure applied to the braking force generation means 41FL and 41RR increases.

  The first pump 56A and the second pump 56B are driven by a pump driving motor 55. The braking control device 1 controls the operation of the pump drive motor 55 based on the drive current of the pump drive motor 55 detected from the ammeter 34 and the rotation angle of the pump drive motor 55 detected from the resolver 35. To do.

  When the first master cut valve 52A and the second master cut valve 52B are opened, the brake fluid discharged from the first pump 56A and the second pump 56B is the master cut valve 52, the first brake fluid reservoir 57A, It circulates between 2 brake fluid reservoirs 57B. For this reason, the master cut valve differential pressure does not occur. On the other hand, when a control current is supplied to the first master cut valve 52A and the second master cut valve 52B and these opening degrees are reduced, a master cut valve differential pressure is generated. As a result, the brake fluid pressure acting on the braking force generating means 41FR, 41RL, 41FL, 41RR can be increased more than the brake fluid pressure in the master cylinder 44.

  Even when the first pump 56A and the second pump 56B are not in operation, the braking force generating means 41FR, by reducing the opening of the first master cut valve 52A and the second master cut valve 52B, The brake fluid pressure acting on 41RL, 41FL, and 41RR can be maintained. Even if the brake fluid pressure in the master cylinder 44 decreases, the opening of the master cut valve 52 is reduced in accordance with the change in the brake fluid pressure in the master cylinder 44, thereby generating a master cut valve differential pressure to control the brake fluid pressure. The brake fluid pressure acting on the power generating means 41FR, 41RL, 41FL, 41RR can be maintained.

  An ammeter 34, a resolver 35, a first outlet side brake hydraulic pressure sensor 36 </ b> A, a second outlet side brake hydraulic pressure sensor 36 </ b> B, and an inclination angle sensor 37 are connected to the braking control device 1. The inclination angle sensor 37 is road surface gradient detection means for detecting information for obtaining the inclination of the road surface on which the vehicle 100 is traveling or stopped. In the present embodiment, as the information, the vehicle 100 is traveling or stopped. The slope of the road surface is detected. Note that the tilt angle detected by the tilt angle sensor 37 is also the tilt angle of the vehicle 100 in the front-rear direction. Further, a yaw rate sensor 38 is connected to the braking control device 1. The yaw rate sensor 38 is a yaw rate detector that detects the yaw rate of the vehicle 100.

  The braking control device 1 controls the operation of the brake actuator 50 to generate a target wheel braking force that is a target wheel braking force for each wheel. The braking control device 1 determines a target wheel braking force for each wheel based on the target vehicle braking force. Here, the target vehicle braking force is a target value required for braking the vehicle 100 according to, for example, the amount of operation state of the brake pedal 20 by the driver. The operation state amount of the brake pedal 20 is, for example, a pedal stroke amount, a pedal stroke position, a pedaling force, a pedal operation speed, and the like. In addition, the target wheel braking force is a braking force that is shared by each wheel in order to apply the target vehicle braking force to the vehicle 100.

  Further, the braking control device 1 can set the required braking force for the vehicle 100 required by the traveling control of the vehicle 100 as the target vehicle braking force. For example, the required braking force required for the vehicle 100 in the follow-up control that travels following the preceding vehicle and the required braking force required for the vehicle 100 in the pre-crash brake control are set as the target vehicle braking force. be able to.

  Further, the braking control device 1 can execute brake hold control (hold control) for holding the brake fluid pressure. The brake hold control is control for holding a braking force that can maintain the vehicle 100 in a stopped state. The brake hold control of the present embodiment is control for holding the brake fluid pressure at a pressure at which the vehicle 100 can be stopped, and is started, for example, while the vehicle 100 is stopped. In the brake hold control, the braking control device 1 controls the first master cut valve 52A and the second master cut valve 52B, and sets the brake hydraulic pressure Pe at the outlets of the first master cut valve 52A and the second master cut valve 52B. Control. In the following description, the brake fluid pressure Pe at the outlets of the master cut valves 52A and 52B is also simply referred to as “exit side brake fluid pressure Pe”. Further, the brake fluid pressure Pi at the inlet of the master cut valves 52A and 52B is also simply referred to as “inlet brake fluid pressure Pi”.

  The brake hold control is executed by, for example, a driver's switch operation. When an operation for instructing execution of brake hold control is performed by the driver, and the vehicle speed is a value indicating a stop state, the brake control device 1 executes brake hold control. Note that the brake hold control may be automatically executed while the vehicle is stopped regardless of the driver's instruction. For example, the brake hold control may be automatically executed when the vehicle 100 stops on an uphill road or a downhill road based on the road surface inclination detected by the inclination angle sensor 37.

  The target value of the outlet side brake fluid pressure Pe in the brake hold control is determined according to, for example, the operation state amount of the brake pedal 20 by the driver or the brake fluid pressure generated by the driver's brake operation. As an example, the target value of the outlet side brake fluid pressure Pe in the brake hold control is determined based on the inlet side brake fluid pressure Pi when the brake hold control is started. The target value of the outlet side brake fluid pressure Pe may be a pressure equal to or slightly lower than the inlet side brake fluid pressure Pi when the vehicle is stopped by a driver's brake operation.

  The braking control device 1 controls the master cut valve 52 based on the determined target value of the outlet brake fluid pressure Pe. In the brake hold control, the holding solenoid valves 53FR, 53FL, 53RR, 53RL are opened, and the pressure reducing solenoid valves 54FR, 54FL, 54RR, 54RL are closed.

  By performing the brake hold control, the vehicle 100 is kept stopped even when the brake is turned off, such as when the driver switches from the brake pedal 20 to the accelerator pedal. Therefore, the vehicle 100 does not move backward even on an uphill road, and a smooth start with a margin can be achieved.

  If the brake hold control end condition is satisfied during execution of the brake hold control, the braking control device 1 ends the brake hold control. An end condition of the brake hold control is that an acceleration request by the driver is detected, for example, an accelerator ON is detected. When the brake hold control end condition is satisfied, the braking control device 1 turns off (opens) the master cut valves 52A and 52B. As a result, the outlet side brake hydraulic pressure Pe is released, and braking on each wheel is released.

  The drive control device 2 can control the power source and the speed change mechanism of the vehicle 100. The drive control device 2 may be capable of independently controlling the power transmitted to each drive wheel. The drive control device 2 is connected to the braking control device 1. The braking control device 1 and the drive control device 2 can mutually control the vehicle 100 by communicating with each other. For example, the braking control device 1 and the drive control device 2 can coordinately control the braking force and driving force of each wheel based on the target braking / driving force of each wheel of the vehicle 100.

  Here, the vehicle 100 may skid while the vehicle 100 is stopped. For example, after the vehicle 100 stops on a hill or the like, the wheel may start to slide due to something. In the side slip of the vehicle 100, for example, as shown in FIG. 3, the yaw rate of the vehicle 100 is generated, for example, the vehicle 100 rotates around the vertical axis of the vehicle 100 around the ground contact surface of one wheel and the road surface. There is. In the following description, unless otherwise specified, the rotation of the vehicle 100 indicates the rotation of the vehicle 100 around the vertical axis of the vehicle 100 (rotation in the yaw direction). In the present embodiment, the behavior (change in attitude) of the vehicle 100 due to the slipping of the wheels and the behavior that accompanies the rotation of the vehicle 100 is referred to as “wiper behavior”. In other words, the wiper behavior is a change in the attitude of the vehicle 100 including a change in the attitude of the vehicle 100 in the yaw direction due to slipping of the wheels.

  When the wiper behavior occurs while the vehicle 100 is stopped, it is desirable that the occurrence of the wiper behavior can be detected promptly. Further, when the wiper behavior occurs, in order to stabilize the behavior of the vehicle 100, it is desirable to reduce the slip between the wheel and the road surface and restore the wheel grip. For example, when a wiper behavior occurs during execution of the brake hold control, it is preferable to release the braking force that has been held so that the wheels can rotate freely.

  The brake control device 1 of the present embodiment determines the wiper behavior based on the direction of the yaw rate detected by the yaw rate sensor 38 as described below. As a result, a behavior higher than the accuracy of the yaw rate sensor 38 can be captured, and the wiper determination can be performed at the initial stage of occurrence of the wiper behavior. Further, when it is determined that the wiper behavior has occurred, the brake control device 1 ends the brake hold control. Thereby, when the wiper behavior occurs, the behavior of the vehicle 100 can be stabilized at an early stage. The braking control device 1 of the present embodiment has a function as an information processing device for a vehicle that determines the behavior of the vehicle 100 due to wheel slip.

  The cause of the yaw rate occurring in the stopped vehicle 100 includes the shake of the vehicle 100 in addition to the wiper behavior. FIG. 4 is a diagram illustrating the rolling of the vehicle 100. As shown in FIG. 4, when the vehicle 100 is shaken in the vehicle width direction (rolling), the yaw rate sensor 38 detects the yaw rate.

  FIG. 5 is a diagram illustrating an example of the yaw rate detected by the yaw rate sensor 38. In FIG. 5, the horizontal axis represents time, and the vertical axis represents the yaw rate (deg / s) detected by the yaw rate sensor 38. In FIG. 5, reference numeral C <b> 1 indicates a yaw rate when the wiper behavior occurs, and reference numeral C <b> 2 indicates a yaw rate when the vehicle 100 rolls. Here, in the yaw rate, a positive value indicates rotation in one direction (for example, clockwise direction) of the vehicle 100, and a negative value indicates rotation in the other direction (for example, counterclockwise direction).

  When the wiper behavior occurs, the yaw rate C1 that has been changing at a substantially constant value until then rises at time t1, and the value increases with time. That is, when wheel slip occurs at time t <b> 1 and the vehicle 100 starts to rotate, the rotational angular velocity in the rotation gradually increases.

  On the other hand, when the vehicle 100 rolls, the yaw rate C2 looks like a sine wave and periodically increases and decreases. Further, in the yaw rate C2, a period having a positive value and a period having a negative value are alternately repeated.

  In the present embodiment, the braking control device 1 makes a wiper pre-determination based on the yaw rate change rate ΔYr so that the start of the wiper behavior can be captured. The brake control device 1 determines that the wiper behavior is occurring when the direction of the yaw rate does not change for a predetermined time after the wiper pre determination is made. Here, the direction of the yaw rate does not change means that if the yaw rate when the wiper pre-determination is set is a positive value, the yaw rate does not change to a negative value, and the wiper pre-determination is made. If the current yaw rate is a negative value, it means that the yaw rate does not change to a positive value. In other words, the wiper determination is finalized when the yaw rate continues to change at a positive value or rises at a negative value after rising. On the other hand, if the yaw rate changes from positive to negative or reverse from negative to positive during a predetermined time, it can be determined that the cause of the yaw rate is a factor other than the wiper behavior such as rolling of the vehicle 100. .

  With reference to FIG. 1, the wiper determination by the vehicle information processing apparatus of this embodiment will be described. The control flow shown in FIG. 1 is repeatedly executed, for example, when the vehicle 100 is stopped and the brake hold control is being performed.

First, in step S1, the braking control device 1 determines whether or not a wiper determination permission condition is satisfied. The wiper determination permission condition is a condition for permitting the determination that the wiper behavior is occurring. For example, the wiper determination permission is permitted when all of the following conditions (i) to (iv) are satisfied. The condition is met.
(I) Idle ON.
(Ii) Not under reduced pressure.
(Iii) The yaw rate sensor 38 is in an effective state.
(Iv) The vehicle speed is zero.

  “Idle ON” in the condition (i) indicates that it is in an idle state. For example, the idle ON condition is satisfied when the accelerator opening or the throttle opening is less than a predetermined opening. The condition (ii) “not under pressure reduction” indicates that the brake fluid pressure is not being reduced in the brake actuator 50. In the present embodiment, the determination of the wiper behavior is performed in order to determine whether it is necessary to end the brake hold control. Therefore, the determination of the wiper behavior is omitted if the brake hydraulic pressure is being reduced.

  The condition (iii) “the yaw rate sensor 38 is in an effective state” indicates that the yaw rate can be effectively detected by the yaw rate sensor 38. The condition (iv) “vehicle speed is 0” indicates that the detected vehicle speed is 0. For example, when the rotational speeds of the four wheels of the vehicle 100 can be detected, the condition that the vehicle speed is zero may be satisfied when the third highest rotational speed of the four wheels is zero.

  As a result of the determination in step S1, if it is determined that the wiper determination permission condition is satisfied (step S1-Y), the process proceeds to step S2, and if not (step S1-N), the process proceeds to step S3.

  In step S2, the brake control device 1 sets the wiper determination permitted state. The braking control device 1 turns on the wiper determination permission flag. When step S2 is executed, the process proceeds to step S4.

  In step S3, the brake control device 1 determines that the wiper determination is not permitted. The braking control device 1 turns off the wiper determination permission flag. When step S3 is executed, the process proceeds to step S4.

In step S4, the brake control device 1 determines whether or not the wiper provisional determination condition is satisfied. For example, the braking control device 1 determines that the temporary wiper determination condition is satisfied when all of the following conditions (v) to (vii) are satisfied.
(V) The wiper is not temporarily determined.
(Vi) The wiper determination is permitted.
(Vii) The state where the yaw rate change rate ΔYr is larger than the predetermined value continues for the provisional determination time Tm1.

  The “wiper temporary determination state” in the condition (v) is a state in which the wiper temporary determination condition is satisfied and the wiper temporary determination flag is set to ON. The “wiper determination permission state” in the condition (vi) is a state where the wiper determination permission flag is ON. The yaw rate change rate ΔYr of the condition (vii) is calculated based on the yaw rate acquired from the yaw rate sensor 38 at a predetermined sampling interval. The change rate ΔYr of the yaw rate is calculated based on the yaw rate acquired 96 ms ago and the yaw rate acquired this time, for example, every 48 ms.

  The predetermined value in the change rate ΔYr of the yaw rate can be set to 2 deg / s / s, for example. For example, the predetermined value may be determined based on an actual measurement value of a yaw rate generated when the vehicle 100 rolls. For example, the predetermined value is preferably a yaw rate change rate ΔYr that does not reach when the vehicle 100 rolls. The temporary determination time Tm1 at the yaw rate change rate ΔYr can be set to, for example, 200 ms.

  As a result of the determination in step S4, if it is determined that the wiper temporary determination condition is satisfied (step S4-Y), the process proceeds to step S5, and if not (step S4-N), the process proceeds to step S6. In FIG. 5, it is determined that the wiper provisional determination condition is satisfied at time t2.

  In step S5, the brake control device 1 sets the wiper provisional determination state. The braking control device 1 sets the wiper temporary determination flag to ON. Moreover, the braking control apparatus 1 substitutes the yaw rate acquired this time for the wiper temporary determination Yr stored value. Here, the wiper temporary determination Yr stored value is used to determine whether or not the sign of the yaw rate is inverted. When step S5 is executed, the process proceeds to step S6.

In step S6, the brake control device 1 determines whether or not the wiper temporary determination cancellation condition is satisfied. The wiper temporary determination cancellation condition is a condition for canceling the wiper temporary determination. For example, the wiper temporary determination state is canceled when any of the following conditions (viii) to (x) is satisfied.
(Viii) The wiper determination is not permitted.
(Ix) The following expressions (1) and (2) are satisfied.
Wiper provisional determination Yr stored value> 0 (1)
Sign inversion value of yaw rate Yr <(wiper temporary determination Yr stored value × 0.5) (2)
(X) The following expressions (3) and (4) are satisfied.
Wiper provisional determination Yr stored value <0 (3)
Yaw rate Yr> (wiper provisional determination Yr stored value × 0.5) sign inversion value (4)

  The condition (ix) is a condition indicating that the yaw rate that has been changing at a positive value has changed to a negative value. On the other hand, the condition (x) is a condition indicating that the yaw rate, which was a negative value, has changed to a positive value. As a result of the determination in step S6, if it is determined that the wiper temporary determination cancellation condition is satisfied (step S6-Y), the process proceeds to step S7. If not (step S6-N), the process proceeds to step S8.

  In step S7, it is determined that the wiper temporary determination is not being performed by the braking control device 1. The braking control device 1 turns off the wiper temporary determination flag. When step S7 is executed, the process proceeds to step S8.

In step S8, the brake control device 1 determines whether or not a wiper determination condition is satisfied. The braking control device 1 determines that the wiper determination condition is satisfied when the following condition (xi) is satisfied and at least one of the conditions (xii) and (xiii) is satisfied.
(Xi) The wiper determination is permitted.
(Xii) The magnitude of the yaw rate is larger than a predetermined threshold value.
(Xiii) The wiper temporary determination state continues for a predetermined time.

  The threshold value in the condition (xii) is determined based on the accuracy of the yaw rate sensor 38, for example. For example, when the design variation of the yaw rate sensor 38 is 3.42 (deg / s), the threshold can be set to 4 (deg / s). The predetermined time Tm2 of the condition (xiii) is set to a time sufficient for determining that the wiper behavior is occurring. The predetermined time Tm2 is determined based on, for example, the natural frequency of the vehicle 100, preferably the natural frequency on the spring of the vehicle 100. That is, the predetermined time Tm2 is determined based on the vibration frequency on the spring of the vehicle 100 when the spring on the vehicle 100 is freely vibrated. For example, when the natural frequency on the spring of the vehicle 100 is a frequency between 1 Hz and 2 Hz, the predetermined time Tm2 can be set to 500 ms. Thereby, the sign of the yaw rate C2 due to the rolling of the vehicle 100 is inverted during the predetermined time Tm2, and can easily be discriminated from the yaw rate C1 due to the wiper behavior.

  As a result of the determination in step S8, if it is determined that the wiper determination condition is satisfied (step S8-Y), the process proceeds to step S9. If not (step S8-N), the process proceeds to step S10. In FIG. 5, it is determined that the wiper determination condition is satisfied at time t3.

  In step S9, the braking control device 1 determines that there is a wiper. The braking control device 1 sets the wiper generation flag to ON. When step S9 is executed, the process proceeds to step S10. When the brake hold control is being performed and the wiper generation flag is turned ON in step S9, the brake control device 1 ends the brake hold control and opens the master cut valve 52. Thereby, holding | maintenance of braking force is complete | finished and it will be in the state which can rotate each wheel of the vehicle 100 freely. Further, when the driver is performing a brake operation when the holding of the braking force is finished, the braking force is under the driver's control.

In step S <b> 10, the brake control device 1 determines whether a release condition with a wiper is satisfied. The braking control device 1 determines that the release condition with the wiper is satisfied when any of the following conditions (xiv) to (xvi) is satisfied.
(Xiv) Wiper is present (wiper generation flag is ON).
(Xv) Idle OFF.
(Xvi) The vehicle speed is equal to or higher than a predetermined vehicle speed.

  The condition (xv) is satisfied, for example, when the accelerator opening or the throttle opening is equal to or greater than a predetermined opening. Moreover, the predetermined vehicle speed of the condition (xvi) can be set to 1 km / h, for example. For example, the condition (xvi) may be satisfied when the vehicle speed based on the lowest rotational speed among the four wheels is equal to or higher than a predetermined vehicle speed.

  As a result of the determination in step S10, if it is determined that the cancellation condition with the wiper is satisfied (step S10-Y), the process proceeds to step S11. If not (step S10-N), the control flow ends. .

  In step S11, the brake control device 1 makes no wiper. The braking control device 1 turns off the wiper generation flag. When step S11 is executed, the control flow ends.

  As described above, the braking control device 1 functioning as the vehicle information processing device of the present embodiment is configured to detect the direction of the detected yaw rate, that is, the direction of rotation of the vehicle 100 indicated by the yaw rate (clockwise or counterclockwise). The behavior of the vehicle 100 due to wheel slip is determined. As a result, even if the yaw rate detected by the yaw rate sensor 38 is a value within the variation range of the yaw rate sensor 38, the wiper determination can be performed. Even if the yaw rate is within the variation range of the yaw rate sensor 38, the increase or decrease of the yaw rate can be grasped. Therefore, as shown in FIG. 5, when the rise of the yaw rate C1 is detected at time t1, the value of the yaw rate C1 before time t1 is temporarily set to 0, and the wiper determination can be performed based on the direction of the yaw rate.

  According to the braking control device 1 of the present embodiment, the yaw rate sensor 38 having the accuracy required to detect the behavior of the vehicle 100 while traveling, that is, the accuracy of the vehicle 100 when the behavior of the vehicle 100 when it is stopped can be detected. Even if the yaw rate sensor 38 is not, the wiper behavior can be determined. Therefore, it is possible to accurately determine the behavior of the vehicle 100 due to wheel slip while suppressing an increase in cost. For example, the wiper behavior can be determined using an existing yaw rate sensor of the vehicle 100 such as a yaw rate sensor provided in a VSC (Vehicle Stability Control) device.

  Further, the braking control device 1 determines that the wiper behavior is occurring when the above condition (vii) is satisfied, that is, when a change (rise) of a predetermined level or more is detected in the yaw rate. The brake control device 1 enables the determination of the presence of the wiper by setting the wiper temporary determination flag to ON when the state in which the yaw rate change rate ΔYr is larger than the predetermined value continues for the temporary determination time Tm1. Thereby, counting of the predetermined time Tm2 can be started based on the rise of the yaw rate due to the wiper behavior, and the start of the wiper behavior can be accurately captured.

  Further, the braking control device 1 determines that the wiper behavior is occurring when the condition (xiii) is satisfied, that is, when the direction of the yaw rate does not change for the predetermined time Tm2 (S8-Y). Accordingly, it is possible to accurately determine the wiper behavior by determining that the vehicle 100 is rolling. In this embodiment, the wiper tentative determination is canceled when the sign of the yaw rate is reversed, but instead, the wiper tentative determination is performed when the yaw rate changes from increase to decrease or when the yaw rate changes from decrease to increase. The determination may be canceled.

  The predetermined time Tm2 is determined based on the natural frequency of the vehicle 100. Accordingly, the braking control device 1 can appropriately determine the wiper behavior by appropriately determining the yaw rate due to the rolling of the vehicle 100.

  Note that the brake control device 1 may determine that the wiper behavior is occurring when the magnitude of the yaw rate continues to increase. As shown in FIG. 5, the magnitude of the yaw rate C1 due to the wiper behavior may continue to increase. On the other hand, the yaw rate C2 due to the rolling of the vehicle 100 is repeatedly increased and decreased. That is, it is possible to determine that the wiper behavior has occurred based on a simple increase or a simple decrease in the yaw rate C1 after the rise. For example, it may be determined that the wiper is present when the duration of the simple increase or decrease in the yaw rate reaches a predetermined time Tm2.

  In the wiper provisional determination condition and the wiper determination condition, the establishment condition may be variable according to the inclination angle of the vehicle 100 detected by the inclination angle sensor 37. For example, when the inclination angle of the vehicle 100 is large for the same yaw rate transition, the temporary wiper determination condition and the wiper determination condition may be more easily established than when the vehicle 100 is small.

(Modification of the embodiment)
In the above embodiment, the determination of the wiper behavior is performed when the vehicle 100 is stopped, but the present invention is not limited to this. The determination of the wiper behavior that determines whether or not the wiper behavior is occurring may be performed while the vehicle 100 is traveling.

  For example, traveling control for automatically controlling the braking / driving force of each wheel on an off-road slope such as a gravel road has been studied. In such traveling control, when going up a hill, some of the wheels may run idle and the ground contact force of the wheels may decrease, causing a wiper behavior. In such a case, it is possible to quickly adjust the distribution of the braking / driving force of each wheel by determining the wiper behavior at the initial stage of the occurrence of the behavior by the braking control device 1. For example, the drive control device 2 can change the drive force distribution of each wheel so as to reduce the drive force distribution of the idling wheel and cancel the wiper behavior.

  Moreover, when going down an off-road hill while performing braking control by the braking control device 1, a wiper behavior may occur due to the locking of some wheels and the reduction of the ground contact force of the wheels. In such a case, it is possible to quickly adjust the distribution of the braking / driving force of each wheel by determining the wiper behavior at the initial stage of the occurrence of the behavior by the braking control device 1. For example, it is possible to change the braking / driving force distribution of each wheel so as to reduce the braking force distribution of the locked wheel and cancel the wiper behavior.

  In addition, a control may be performed in which a wiper behavior when traction control is being performed is determined and a warning is given to the driver. The determination of the wiper behavior may be performed at the time of traveling that can be premised on the yaw rate being zero, such as when the vehicle 100 is traveling straight.

  The determination of the wiper behavior while the vehicle 100 is traveling may be performed, for example, when the vehicle 100 is traveling at a very low speed. As an example, the wiper behavior may be determined when the vehicle 100 is traveling at a speed equal to or lower than the speed at which a person walks.

  As described in the above embodiment and the present modification, the determination of the wiper behavior by the braking control device 1 can be performed when the assist control of the braking / driving force is being performed in the vehicle 100. When it is determined that the wiper behavior is occurring when the assist control is being performed, the assist control can be promptly terminated. When the assist control causes the wiper behavior or promotes the wiper behavior, the wiper behavior can be eliminated or the wiper behavior can be suppressed by terminating the assist control.

  Further, when the wiper behavior occurs, the driving operation may be assisted by assist control or other control so that the wiper behavior can be eliminated or suppressed. Since the braking control device 1 according to the embodiment and the modification can capture a change in the attitude of the vehicle 100 at the initial stage of the wiper behavior, it is advantageous in eliminating the wiper behavior and suppressing the wiper behavior.

  The contents disclosed in the above embodiments and modifications can be executed in appropriate combination.

  As described above, the vehicle information processing apparatus according to the present invention is suitable for accurately determining the behavior of the vehicle due to wheel slip.

1-1 Vehicle Control Device 1 Braking Control Device 2 Drive Control Device 37 Inclination Angle Sensor 38 Yaw Rate Sensor 50 Brake Actuator 100 Vehicle ΔYr Yaw Rate Change Speed Tm1 Temporary Determination Time Tm2 Predetermined Time

Claims (8)

An information processing apparatus for a vehicle, wherein a behavior of the vehicle due to slipping of a wheel of the vehicle is determined based on a direction of the yaw rate detected by a yaw rate detection unit that detects a yaw rate of the vehicle. The vehicle information processing device according to claim 1, wherein the behavior is determined to occur when the direction of the yaw rate does not change for a predetermined time. The vehicle information processing apparatus according to claim 2, wherein the predetermined time is determined based on a natural frequency of the vehicle. The vehicle information processing apparatus according to any one of claims 1 to 3, wherein the behavior is determined to occur when the magnitude of the yaw rate continues to increase. The vehicular information processing apparatus according to any one of claims 1 to 4, wherein the behavior is determined to occur when a change of a predetermined degree or more is detected in the yaw rate. The vehicle information processing apparatus according to any one of claims 1 to 5, wherein the behavior is determined when the vehicle is stopped. The vehicle information processing apparatus according to any one of claims 1 to 6, wherein the behavior is determined when control is performed to maintain a braking force capable of maintaining a stopped state in the vehicle. The vehicle information processing device according to claim 7 is provided.
A vehicle control device that terminates the holding of the braking force when it is determined that the behavior occurs.

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