JP2019172014A - Control apparatus for vehicle - Google Patents

Abstract

To execute, in a control apparatus for a vehicle which executes vehicle yaw control for adding a yaw moment to the vehicle, the vehicle yaw control while taking the operation state of side-slip reduction control into account, thereby appropriately suppressing a sense of discomfort given to a driver by the control.SOLUTION: A control apparatus for a vehicle comprises: a steering device including a steering wheel 6, etc.; a brake device 16 capable of applying different braking forces to left and right wheels; and a PCM 14 including a processor, etc. In response to the returning operation of the steering wheel 6, the PCM 14 executes vehicle yaw control for controlling the brake device 16 so as to add, to a vehicle 1, a yaw moment in a direction opposite to the direction of a yaw rate generated in the vehicle 1. When a DSC change-over switch 13 is turned off, and the non-operation of side-slip reduction control is set, the PCM 14 suppresses the vehicle yaw control.SELECTED DRAWING: Figure 6

Description

  The present invention relates to a vehicle control device, and more particularly to a vehicle control device including a brake device capable of applying different braking forces to left and right wheels.

  2. Description of the Related Art Conventionally, there are known devices that control the behavior of a vehicle in a safe direction when the behavior of the vehicle becomes unstable due to slip or the like (such as a skid prevention device). Specifically, it is known to detect that understeer or oversteer behavior has occurred in the vehicle during cornering of the vehicle, and to impart appropriate deceleration to the wheels to suppress them. ing.

  In addition, unlike the control for improving the safety in the driving state where the behavior of the vehicle becomes unstable as described above, the acceleration / deceleration automatically linked with the steering operation operated from the daily driving range is automatically performed. 2. Description of the Related Art A vehicle motion control device that reduces skid in a driving region is known (for example, see Patent Document 1). In particular, this Patent Document 1 discloses a vehicle motion control device including a first mode for controlling acceleration / deceleration in the longitudinal direction of the vehicle and a second mode for controlling the yaw moment of the vehicle. Yes.

Japanese Patent No. 5143103

  As described above, in the technique disclosed in Patent Document 1, the yaw moment is applied to the vehicle in the second mode. The control for applying the yaw moment to the vehicle is typically executed when a steering wheel (hereinafter simply referred to as “steering”) is switched back. That is, when the steering is turned back, a yaw moment reverse to the yaw rate generated in the vehicle is added to suppress the turning of the vehicle, in other words, to promote the return of the vehicle in the straight direction. As described above, a braking force is applied to the turning outer wheel by the brake device. Hereinafter, the control for adding such a yaw moment to the vehicle is appropriately referred to as “vehicle yaw control”.

  By the way, side slip reduction control for reducing the side slip of the vehicle when the behavior of the vehicle becomes unstable due to slip or the like is known. Specifically, when the vehicle is cornered, it is detected that understeer or oversteer behavior has occurred in the vehicle, and an appropriate deceleration is applied to the wheels to suppress them. Stability control system) is known. A vehicle capable of executing the side slip reduction control may be provided with a switch for setting operation or non-operation of the side slip reduction control. In such a vehicle, if the vehicle yaw control is executed when the driver operates the switch to disable the skid reduction control, that is, when the driver does not expect the control intervention, the control intervention is performed by the driver. May give a sense of incongruity.

  The present invention has been made in order to solve the above-described problems of the prior art. In a vehicle control apparatus that performs vehicle yaw control that adds a yaw moment to a vehicle, the operational state of skid reduction control is considered. An object of the present invention is to appropriately suppress the uncomfortable feeling given to the driver by the vehicle yaw control.

In order to achieve the above-mentioned object, the present invention sets the operation or non-operation of the steering device, the brake device capable of applying different braking forces to the left and right wheels, and the skid reduction control for reducing the skid of the vehicle. A control device for a vehicle having a switching device that accepts the operation of the vehicle and a controller, wherein the controller generates a yaw moment that is reverse to the yaw rate generated in the vehicle based on a return operation of the steering device. Vehicle yaw control for controlling the brake device to be added to the vehicle, and when the non-operation of the skid reduction control is set by the switching device, the vehicle yaw control is configured to be suppressed. .
According to the present invention configured as described above, since the vehicle yaw control is suppressed when the non-operation of the skid reduction control is set by the switching device, the driver feels uncomfortable by executing the vehicle yaw control at this time. Can be appropriately suppressed.

In the present invention, preferably, the controller is configured to suppress the vehicle yaw control when the non-operation of the skid reduction control is set by the switching device and the lateral acceleration of the vehicle becomes a predetermined value or more.
According to the present invention configured as described above, in addition to the non-operation of the skid reduction control being set, the lateral acceleration generated in the vehicle is relatively high, so that the driver can perform sports driving, etc. The vehicle yaw control can be suppressed when it is certain that the skid reduction control is intentionally set to non-operation. Therefore, it is possible to appropriately suppress the driver from feeling uncomfortable by executing the vehicle yaw control when there is a high possibility that the driver does not expect control intervention.

In the present invention, preferably, the controller is configured to suppress the vehicle yaw control when the non-operation of the skid reduction control is set by the switching device and the outside air temperature is equal to or higher than a predetermined value.
According to the present invention configured as described above, in addition to the non-operation of the skid reduction control being set, the road surface is not in a slippery state like a snowy road because the outside air temperature is relatively high. When it is certain, the vehicle yaw control can be suppressed. Therefore, it is possible to appropriately suppress the driver from feeling uncomfortable by executing the vehicle yaw control when there is a high possibility that the driver does not expect control intervention.

In the present invention, it is preferable that the switching device sets the operation of the skid reduction control when the power of the vehicle is turned on.
According to the present invention configured as described above, in order to set the skid reduction control to the non-operation, the skid reduction control can be set to the non-operation by the switching device after the vehicle power is turned on. This is necessary, and it is possible to prevent the skid reduction control from being deactivated against the driver's intention. In other words, when the non-operation of the skid reduction control is set by the switching device, the driver assumes that there is no intervention of the skid reduction control, and in such a case, by suppressing the vehicle yaw control By executing the vehicle yaw control, it is possible to appropriately suppress the driver from feeling uncomfortable.

In the present invention, it is preferable that the controller executes vehicle yaw control when a value corresponding to a return operation of the steering device becomes equal to or greater than a predetermined threshold, and the non-operation of the side slip reduction control is set by the switching device. In such a case, the threshold value is configured to be larger than when the operation of the side slip reduction control is set.
According to the present invention configured as described above, when the non-operation of the skid reduction control is set, it is determined whether or not the vehicle yaw control is executed more than when the operation of the skid reduction control is set. Therefore, the vehicle yaw control can be effectively suppressed at this time.

In the present invention, it is preferable that the controller adds the yaw to be added by the vehicle yaw control when the non-operation of the side slip reduction control is set by the switching device than when the operation of the side slip reduction control is set. It is configured to reduce the moment.
According to the present invention configured as described above, when the non-operation of the side slip reduction control is set, the yaw moment added by the vehicle yaw control is greater than when the operation of the side slip reduction control is set. Therefore, vehicle yaw control can be effectively suppressed at this time.

In the present invention, preferably, the controller is configured to prohibit the vehicle yaw control when the non-operation of the skid reduction control is set by the switching device.
According to the present invention configured as described above, since the vehicle yaw control is prohibited when the non-operation of the skid reduction control is set, the vehicle yaw control is executed at this time, so that the driver feels uncomfortable. Can be reliably suppressed.

  According to the present invention, in a vehicle control device that performs vehicle yaw control that adds a yaw moment to a vehicle, the vehicle yaw control is executed in consideration of the operating state of the skid reduction control, so that the driver feels uncomfortable. Can be suppressed appropriately.

1 is a block diagram showing an overall configuration of a vehicle equipped with a vehicle control device according to an embodiment of the present invention. It is a block diagram which shows the electric constitution of the control apparatus of the vehicle by embodiment of this invention. It is a flowchart of the attitude | position control process by embodiment of this invention. It is a flowchart of the additional deceleration setting process by embodiment of this invention. 6 is a map showing the relationship between additional deceleration and steering speed according to an embodiment of the present invention. It is a flowchart of the target yaw moment setting process by embodiment of this invention. It is the table | surface which showed the threshold value and gain used in the target yaw moment setting process by embodiment of this invention. It is a flowchart of the attitude | position control process by the modification of embodiment of this invention. It is the table | surface which showed the threshold value and gain used in the target yaw moment setting process by the modification of embodiment of this invention.

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

<System configuration>
First, referring to FIG. 1, a system configuration of a vehicle equipped with a vehicle control apparatus according to an embodiment of the present invention will be described. FIG. 1 is a block diagram showing the overall configuration of a vehicle equipped with a vehicle control apparatus according to an embodiment of the present invention.

  In FIG. 1, the code | symbol 1 shows the vehicle carrying the vehicle control apparatus by this embodiment. An engine 4 is mounted on the vehicle body front portion of the vehicle 1 as a drive source for driving drive wheels (left and right front wheels 2 in the example of FIG. 1). The engine 4 is an internal combustion engine such as a gasoline engine or a diesel engine. In the present embodiment, the engine 4 is a gasoline engine having a spark plug.

  The vehicle 1 mainly serves as a rotation angle of a steering device (steering wheel 6 or the like) for steering the vehicle 1 and a steering column (not shown) connected to the steering wheel 6 in the steering device. A steering angle sensor 8 that detects a steering angle, a vehicle speed sensor 9 that detects vehicle speed, an acceleration sensor 10 that detects acceleration, an outside air temperature sensor 11 that detects outside air temperature, a yaw rate sensor 12 that detects yaw rate, and a vehicle A DSC selector switch 13 (switching device) that receives an operation for setting the operation or non-operation of the side slip reduction control (hereinafter also simply referred to as “DSC”) for reducing one side slip. Each of these sensors outputs a detected value to a PCM (Power-train Control Module) 14.

  The vehicle 1 also includes a brake control system 18 that supplies brake fluid pressure to a wheel cylinder and a brake caliper of a brake device 16 provided on each wheel. The brake control system 18 includes a hydraulic pump 20 that generates a brake hydraulic pressure necessary to generate a braking force in the brake device 16 provided on each wheel. The hydraulic pump 20 is driven by, for example, electric power supplied from a battery, and generates the brake hydraulic pressure necessary for generating the braking force in each brake device 16 even when the brake pedal is not depressed. It is possible. Moreover, the brake control system 18 is provided in a hydraulic pressure supply line to the brake device 16 of each wheel, and a valve unit 22 for controlling the hydraulic pressure supplied from the hydraulic pump 20 to the brake device 16 of each wheel. (Specifically, a solenoid valve). For example, the opening degree of the valve unit 22 is changed by adjusting the amount of power supplied from the battery to the valve unit 22. The brake control system 18 also includes a hydraulic pressure sensor 24 that detects the hydraulic pressure supplied from the hydraulic pump 20 to the brake device 16 of each wheel. The hydraulic pressure sensor 24 is disposed, for example, at a connection portion between each valve unit 22 and the hydraulic pressure supply line on the downstream side thereof, detects the hydraulic pressure on the downstream side of each valve unit 22, and detects the detected value as a PCM (Power-train). Control Module) 14.

  The brake control system 18 calculates the hydraulic pressure supplied independently to each wheel cylinder and brake caliper of each wheel based on the braking force command value input from the PCM 14 and the detection value of the hydraulic pressure sensor 24, The rotational speed of the hydraulic pump 20 and the opening degree of the valve unit 22 are controlled in accordance with the hydraulic pressure.

  Next, the electrical configuration of the vehicle control apparatus according to the embodiment of the present invention will be described with reference to FIG. FIG. 2 is a block diagram showing an electrical configuration of the vehicle control apparatus according to the embodiment of the present invention.

  PCM14 by this embodiment is based on the detection signal which the various sensors which detect the driving | running state of the engine 4 output other than the detection signal of the sensor 8,10,12,24 mentioned above and the output signal of DSC changeover switch 13 based on the above-mentioned. Control of each part of the engine 4 (typically a spark plug 26. In addition, a throttle valve, a turbocharger, a variable valve mechanism, a fuel injection valve, an EGR device, etc.) and a brake control system 18 A control signal is output to do this.

  Each of the PCM 14 and the brake control system 18 includes one or more processors, various programs interpreted and executed on the processors (a basic control program such as an OS, and an application program that is activated on the OS and realizes a specific function. ), And a computer having an internal memory such as a ROM or RAM for storing programs and various data. Although details will be described later, the PCM 14 and the brake control system 18 correspond to a “controller” in the present invention.

<Slide reduction control>
Next, an outline of the skid reduction control will be described. In this embodiment, the PCM 14 performs the skid reduction control, but a DSC unit (not shown) different from the PCM 14 may perform the skid reduction control. The same control as conventionally known can be applied to the side slip reduction control executed by the PCM 14. This side slip reduction control is performed by the target yaw rate calculated by the side slip angle of the vehicle 1, the steering angle detected by the steering angle sensor 8 and the vehicle speed detected by the vehicle speed sensor 9, and the yaw rate (actual yaw rate) detected by the yaw rate sensor 12. It is executed in a situation (so-called limit region) where the difference between and becomes very large.

  Specifically, when the DSC changeover switch 13 is turned on, that is, when the operation of the side slip reduction control is set, the PCM 14 detects when understeer or oversteer behavior occurs in the vehicle 1. The braking force of each wheel of the vehicle 1 is controlled so as to suppress this, or the output torque of the engine 4 is reduced. For example, the PCM 14 sets the brake control system 18 so that the yaw rate detected by the yaw rate sensor 12 matches the target yaw rate calculated based on the steering angle detected by the steering angle sensor 8 and the vehicle speed detected by the vehicle speed sensor 9. Via the control, the braking force of each wheel of the vehicle 1 is controlled. The DSC changeover switch 13 is turned on by a driver's operation, and is also reset to on when the ignition of the vehicle 1 is turned on.

  On the other hand, the PCM 14 does not execute the skid reduction control when the DSC changeover switch 13 is turned off, that is, when the non-operation of the skid reduction control is set. That is, even if understeer or oversteer behavior occurs in the vehicle 1, control for suppressing them is not executed. As described above, the DSC changeover switch 13 is reset to ON when the ignition of the vehicle 1 is turned ON from OFF. That is, in order to prevent the side slip reduction control from being executed, it is necessary that the driver intentionally operates the DSC changeover switch 13 after turning on the ignition of the vehicle 1. In other words, when the DSC changeover switch 13 is turned off, it can be said that there is a clear intention of the driver to disable the skid reduction control.

<Vehicle attitude control>
Next, specific control contents executed by the vehicle control device will be described. First, an overall flow of the attitude control process performed by the vehicle control device in the embodiment of the present invention will be described with reference to FIG. FIG. 3 is a flowchart of the attitude control process according to the embodiment of the present invention.

The attitude control process of FIG. 3 is started when the ignition of the vehicle 1 is turned on and the PCM 14 is powered on, and is repeatedly executed at a predetermined cycle (for example, 50 ms).
When the attitude control process is started, as shown in FIG. 3, in step S <b> 1, the PCM 14 acquires various information of the vehicle 1. Specifically, the PCM 14 detects detection signals output from various sensors of the vehicle 1 including the steering angle detected by the steering angle sensor 8, the vehicle speed detected by the vehicle speed sensor 9, the yaw rate detected by the yaw rate sensor 12, and the like. An output signal corresponding to ON / OFF of the changeover switch 13 is acquired.

Next, in step S <b> 2, the PCM 14 executes an additional deceleration setting process and sets an additional deceleration to be added to the vehicle 1.
Subsequently, in step S <b> 3, the PCM 14 executes a target yaw moment setting process, and sets a target yaw moment that is reverse to the actual yaw rate to be applied to the vehicle 1.

  Next, in step S4, the PCM 14 controls the engine 2 so as to add the additional deceleration set in step S2 to the vehicle 1. In this case, the PCM 14 decreases the output torque of the engine 2 so as to add the set additional deceleration to the vehicle 1. Typically, the PCM 14 controls the spark plug 26 so as to retard the ignition timing in the engine 4 to reduce the output torque of the engine 2.

  In step S4, the brake control system 18 controls the brake device 16 so as to give the vehicle 1 the target yaw moment that is reverse to the actual yaw rate set in step S3 (vehicle yaw control). This vehicle yaw control is executed in a daily steering scene (a situation where the side slip angle and the difference between the target yaw rate and the actual yaw rate are relatively smaller than the situation in which the side slip reduction control is executed), unlike the side slip reduction control described above. The

  Specifically, the brake control system 18 stores in advance a map that defines the relationship between the yaw moment command value and the rotational speed of the hydraulic pump 20, and by referring to this map, the target yaw of step S3 is stored. The hydraulic pump 20 is operated at the rotational speed corresponding to the yaw moment command value set in the moment setting process (for example, by increasing the power supplied to the hydraulic pump 20, the rotational speed corresponding to the braking force command value). Until the rotational speed of the hydraulic pump 20 is increased).

  In addition, the brake control system 18 stores, for example, a map that prescribes the relationship between the yaw moment command value and the opening degree of the valve unit 22 in advance, and corresponds to the yaw moment command value by referring to this map. The valve unit 22 is individually controlled so as to have an opening (for example, by increasing the power supplied to the solenoid valve, the opening of the solenoid valve is increased to the opening corresponding to the braking force command value). Adjust the braking force of the wheels. The brake control system 18 does not perform the control in step S4 when the target yaw moment is not set in step S3.

  After step S4 described above, the PCM 14 ends the attitude control process.

  Next, the additional deceleration setting process according to the embodiment of the present invention will be described with reference to FIGS. FIG. 4 is a flowchart of the additional deceleration setting process according to the embodiment of the present invention, and FIG. 5 is a map showing the relationship between the additional deceleration and the steering speed according to the embodiment of the present invention.

  As shown in FIG. 4, when the additional deceleration setting process is started, in step S11, the PCM 14 calculates a steering speed based on the steering angle acquired in step S1 of the attitude control process of FIG.

Next, in step S12, PCM 14 determines in turning operation of the steering wheel 6 (i.e. the steering angle (absolute value) in the increase) of and the steering speed whether a predetermined threshold value S ₁ or more.
As a result, if the operation in and steering speed cut is the threshold value S ₁ or more, the flow advances to step S13, PCM 14 sets the deceleration with based on the steering speed. This additional deceleration is a deceleration to be added to the vehicle 1 in accordance with the steering operation in order to accurately realize the vehicle behavior intended by the driver.

Specifically, the PCM 14 sets an additional deceleration corresponding to the steering speed calculated in step S11 based on the relationship between the steering speed and the additional deceleration shown in the map of FIG.
The horizontal axis in FIG. 5 indicates the steering speed, and the vertical axis indicates the additional deceleration. As shown in FIG. 5, when the steering speed is less than the threshold value S ₁ , the corresponding additional deceleration is zero. Namely, when the steering speed is less than the threshold value S _1, PCM 14 does not perform the control for adding the deceleration of the vehicle 1 based on the steering operation (specifically, reduction of the output torque of the engine 4).
On the other hand, when the steering speed is the threshold value S ₁ or more, according to the steering speed increases, additional deceleration corresponding to the steering speed is asymptotic to a predetermined upper limit value D _max. That is, the additional deceleration increases as the steering speed increases, and the increase rate of the increase amount decreases. This upper limit value D _max is set to such a deceleration that the driver does not feel that there is control intervention even if deceleration is added to the vehicle 1 in accordance with the steering operation (for example, 0.5 m / s ² ≈0). .05G).
Further, when the steering speed is equal to or higher than the threshold value S ₂ larger than the threshold value S ₁ , the additional deceleration is maintained at the upper limit value D _max .
After step S13, the PCM 14 ends the additional deceleration setting process and returns to the main routine.

Also, not in turning operation of the steering wheel 6 (i.e. steering angle in a constant or decreases) in step S12 or if the steering speed is less than the threshold value S _1, PCM 14 will terminate the addition deceleration setting process, the main routine Return to.

  The PCM 14 reduces the output torque of the engine 4 in step S4 of the attitude control process of FIG. 3 so as to realize the additional deceleration set based on the increase speed of the steering angle in the additional deceleration setting process described above. As described above, when the steering wheel 6 is cut, the output torque of the engine 4 is decreased based on the steering speed to increase the vertical load of the front wheel 2, which is favorable for the cutting operation by the driver. The behavior of the vehicle 1 can be controlled with responsiveness.

  Next, the target yaw moment setting process in the embodiment of the present invention will be described with reference to FIGS.

  FIG. 6 is a flowchart of the target yaw moment setting process according to the embodiment of the present invention, and FIG. 7 is a table showing thresholds and gains used in the target yaw moment setting process according to the embodiment of the present invention.

  As shown in FIG. 6, when the target yaw moment setting process is started, in step S31, the PCM 14 determines the target yaw rate and the target lateral jerk based on the steering angle and the vehicle speed acquired in step S1 of the attitude control process of FIG. calculate. Specifically, the PCM 14 calculates the target yaw rate by multiplying the steering angle by a coefficient corresponding to the vehicle speed. Further, the PCM 14 calculates a target lateral jerk based on the steering speed and the vehicle speed.

  Next, in step S32, the PCM 14 sets a difference (yaw rate difference) Δγ between the yaw rate (actual yaw rate) detected by the yaw rate sensor 12 acquired in step S1 of the attitude control process of FIG. 3 and the target yaw rate calculated in step S31. calculate.

Next, in step S33, the PCM 14 sets threshold values Y ₁ and S ₃ used in the determination in the following process according to the state (that is, on or off) of the DSC changeover switch 13 acquired in step S1, and The gain used to set the target yaw moment is set by the following process.

First, the setting of threshold values Y ₁ and S ₃ will be specifically described with reference to FIG. These threshold values Y ₁ and S ₃ are used in different determinations in step S34 (including S36) and step S37, which will be described later. Basically, the threshold values Y ₁ and S ₃ are predetermined values corresponding to the switchback operation of the steering wheel 6. If the parameter is the threshold value Y ₁ and S ₃ above, the target yaw when used to set the target yaw moment to be given to the vehicle (i.e. a predetermined parameter is less than the threshold value Y ₁ and S ₃ Moment is not set). In the description of FIG. 7, “threshold value Y ₁ ” and “threshold value S ₃ ” may be simply referred to as “threshold value”.

The table shown in FIG. 7 is created in advance and stored in a memory or the like. In this table, the magnitude relation of the threshold is defined for each of the cases where the DSC changeover switch 13 is on and off. Specifically, as shown in FIG. 7, when the DSC changeover switch 13 is off (ie, when the non-operation of the side slip reduction control is set), the DSC changeover switch 13 is on (ie, The threshold value is defined so that both the threshold value Y ₁ and the threshold value S ₃ are increased, so that the threshold value is larger than when the side slip reduction control is set.

  By applying such a threshold value, when the DSC changeover switch 13 is OFF, a predetermined parameter according to the switchback operation of the steering wheel 6 (in other words, a predetermined parameter according to the turning state of the vehicle 1) is obtained. It becomes difficult to satisfy the condition that the threshold is exceeded. As a result, it is less likely that the target yaw moment is set in the following processing. That is, when the DSC changeover switch 13 is off and the non-operation of the side slip reduction control is set, the control (vehicle yaw control) that applies the yaw moment reverse to the actual yaw rate to the vehicle 1 by the brake device 16 is suppressed. In other words, the vehicle yaw control is difficult to be executed. As a result, it is possible to appropriately suppress the driver from feeling uncomfortable by executing the vehicle yaw control when the non-operation of the side slip reduction control is set.

  On the other hand, by applying the threshold value as described above, when the DSC changeover switch 13 is on, the condition that the predetermined parameter corresponding to the switchback operation of the steering wheel 6 is equal to or greater than the threshold value is easily established. As a result, there is a high possibility that the target yaw moment is set in the following processing. That is, the vehicle yaw control is promoted when the DSC changeover switch 13 is on and the operation of the side slip reduction control is set, in other words, the vehicle yaw control is easily performed. Thereby, when the operation of the side slip reduction control is set, the vehicle yaw control can be surely executed to improve the response of the vehicle 1, that is, the vehicle behavior is quickly stabilized according to the driver's steering operation. Can be made.

FIG. 7 schematically shows the tendency of both the threshold values Y ₁ and S ₃ according to the steering speed. Actually, according to such a tendency, the threshold value depends on the traveling direction of the vehicle 1. Each of Y ₁ and S ₃ is set separately. That is, for each of the threshold value Y ₁ and the threshold value S ₃ used in different determinations in step S34 (including S36) and step S37, a table corresponding to whether the DSC selector switch 13 is turned on or off is defined. Y ₁ and the threshold value S ₃ are set to different values. Further, these threshold values Y ₁ and S ₃ are set by adaptation according to the characteristics of the vehicle 1 to which the vehicle yaw control is applied by conducting simulations and experiments in advance (the same applies to the gain described later). is there).

  Next, with reference to FIG. 7, the gain used for setting the target yaw moment in the embodiment of the present invention will be specifically described. In the table shown in FIG. 7, the magnitude relation of the gain is defined for each of the cases where the DSC changeover switch 13 is on and off. This gain is set to a value from 0 to 1 (0 ≦ gain ≦ 1), and is used to multiply a target yaw moment calculated by a method described later. That is, a value obtained by multiplying a gain that is a value from 0 to 1 is used as a target yaw moment to be finally applied.

  Specifically, as shown in FIG. 7, it is defined that the gain is smaller when the DSC changeover switch 13 is off than when the DSC changeover switch 13 is on. According to such a gain, when the DSC changeover switch 13 is OFF, the target yaw moment is reduced. As a result, when the DSC change-over switch 13 is off and the non-operation of the skid reduction control is set, the vehicle yaw control is substantially suppressed. This also makes it possible to appropriately suppress the driver from feeling uncomfortable by executing the vehicle yaw control when the non-operation of the skid reduction control is set.

  On the other hand, according to the gain as described above, the target yaw moment increases when the DSC changeover switch 13 is on. As a result, when the DSC selector switch 13 is on and the operation of the side slip reduction control is set, the control (vehicle yaw control) for applying the yaw moment reverse to the actual yaw rate to the vehicle 1 by the brake device 16 is performed. It will be substantially promoted. This also makes it possible to quickly stabilize the vehicle behavior according to the driver's steering operation when the operation of the skid reduction control is set.

  In the processing described later, target yaw moments are set separately in different steps S35 and S38, but different values of gain are used in setting the target yaw moments in these different steps S35 and S38. Also good. Even in such a case, basically, the gain may be reduced when the DSC selector switch 13 is OFF.

Returning to FIG. 6, the description of the processing after step S <b> 34 is resumed. In step S34, the PCM 14 is in the operation of turning back the steering wheel 6 (ie, the steering angle is decreasing), and the change rate Δγ ′ of the yaw rate difference obtained by time differentiation of the yaw rate difference Δγ is the threshold value Y _1. It is determined whether it is above. PCM14 as the threshold Y _1, using the value set in step S33.

As a result, 'when is the threshold value Y ₁ or more, the process proceeds to step S35, PCM 14 is change rate Δγ in the yaw rate difference' change rate Δγ in and yaw rate difference in the returning operation and, on the gain set in step S33 Based on this, a yaw moment reverse to the actual yaw rate of the vehicle 1 is set as the target yaw moment. Specifically, the PCM 14 calculates the magnitude of the reference target yaw moment by multiplying a predetermined coefficient by the change rate Δγ ′ of the yaw rate difference, and further increases the gain with respect to the reference target yaw moment. By multiplying, the magnitude of the target yaw moment to be applied to the vehicle 1 is calculated.

On the other hand, if it is determined in step S34 that the steering wheel 6 is not being switched back (that is, the steering angle is constant or increasing), the process proceeds to step S36 where the PCM 14 sets the actual yaw rate as the target yaw rate change rate Δγ ′. It is determined whether or not the direction is greater than the yaw rate (that is, the direction in which the behavior of the vehicle 1 is oversteered) and the change rate Δγ ′ of the yaw rate difference is equal to or greater than the threshold Y ₁ . Specifically, when the yaw rate difference is decreasing under a situation where the target yaw rate is equal to or higher than the actual yaw rate, or when the yaw rate difference is increasing under a situation where the target yaw rate is less than the actual yaw rate, The change rate Δγ ′ of the yaw rate difference is determined to be a direction in which the actual yaw rate is greater than the target yaw rate.

As a result, when the change rate Δγ in the yaw rate difference is 'change rate Δγ of it and the yaw rate difference in the direction of the actual yaw rate is greater than the target yaw rate' is the threshold value Y ₁ or more, the process proceeds to step S35, PCM 14, similarly to the above Thus, based on the change rate Δγ ′ of the yaw rate difference and the gain set in step S33, the yaw moment that is the reverse of the actual yaw rate of the vehicle 1 is set as the target yaw moment.

After step S35, or if the change rate Δγ in the yaw rate difference 'change rate Δγ if yaw rate difference actual yaw rate is not larger direction than the target yaw rate' is less than the threshold value Y ₁ at step S36, the process proceeds to step S37 , PCM 14 is cut back during operation of the steering wheel 6 (i.e. in the steering angle is decreased), and the steering speed is determined whether a predetermined threshold S ₃ or more. PCM14 as the threshold S _3, using the value set in step S33.

As a result, if and steering speed in the switch-back is the threshold value S ₃ or more, the process proceeds to step S38, PCM 14 includes a target lateral jerk calculated in step S31, based on the gain set in step S33, the vehicle 1 A yaw moment reverse to the actual yaw rate is set as the second target yaw moment. Specifically, the PCM 14 calculates the magnitude of the second target yaw moment serving as a reference by multiplying the target lateral jerk by a predetermined coefficient, and gains relative to the second target yaw moment serving as the reference. Is further multiplied to calculate the magnitude of the second target yaw moment to be applied to the vehicle 1.

After step S38, the or when cut is not being returning operation (i.e. the steering angle is in constant or increased) or steering speed of the steering wheel 6 is less than the threshold value S ₃ in step S37, the process proceeds to step S39, PCM 14 Sets the larger one of the target yaw moment set in step S35 and the second target yaw moment set in step S38 as the yaw moment command value. If the target yaw moment is not set in both step S35 and step S38 (that is, if both the processes in steps S35 and S38 are not executed), the PCM 14 does not set the yaw moment command value in step S39. . After step S39, the PCM 14 ends the target yaw moment setting process and returns to the main routine.

<Effect>
Next, functions and effects of the vehicle control apparatus according to the embodiment of the present invention will be described.

  According to the present embodiment, when the DSC changeover switch 13 is OFF and the non-operation of the side slip reduction control is set, the PCM 14 generates a yaw moment that is opposite to the actual yaw rate generated in the vehicle 1. Vehicle yaw control for adding to is suppressed. As a result, it is possible to appropriately suppress the driver from feeling uncomfortable by executing the vehicle yaw control when the non-operation of the side slip reduction control is set.

  Further, according to the present embodiment, the DSC changeover switch 13 is reset to ON when the power source of the vehicle 1 is turned ON from OFF, and sets the operation of the skid reduction control. Thereby, in order to set the skid reduction control to non-operation, an operation by the driver is required, and it is possible to prevent the skid reduction control from being deactivated against the driver's intention. In other words, in order to prevent the side slip reduction control from being executed, it is necessary for the driver to intentionally operate the DSC changeover switch 13 after turning on the vehicle 1. Therefore, when the DSC changeover switch 13 is off and the non-operation of the skid reduction control is set, it can be said that there is a clear intention of the driver that he wants to deactivate the skid reduction control. In such a case, if the vehicle yaw control is executed in an everyday steering scene, the vehicle yaw control intervention tends to be uncomfortable for the driver. Therefore, in this embodiment, when the DSC changeover switch 13 is off and the non-operation of the skid reduction control is set, it is possible to appropriately suppress the driver from feeling uncomfortable by suppressing the vehicle yaw control. It becomes like this.

Further, according to the present embodiment, the PCM 14 has a value (yaw rate difference change speed Δγ ′ or steering speed) corresponding to the switching back operation of the steering wheel 6 equal to or greater than a predetermined threshold (threshold Y ₁ or S ₃ ). When the vehicle yaw control is executed and the DSC changeover switch 13 is off and the non-operation of the side slip reduction control is set, the DSC changeover switch 13 is on and the operation of the side slip reduction control is set. Since the threshold value is made larger than when the vehicle is on, vehicle yaw control can be effectively suppressed when the non-operation of the skid reduction control is set.

  Further, according to the present embodiment, when the DSC changeover switch 13 is off and the non-operation of the side slip reduction control is set, the PCM 14 sets the DSC changeover switch 13 on and sets the operation of the side slip reduction control. Since the yaw moment applied by the vehicle yaw control is made smaller by the gain than in the case where it is set, the vehicle yaw control can be effectively suppressed when the non-operation of the skid reduction control is set.

<Modification>
Next, a modification of the present embodiment (synonymous with other embodiments) will be described. A plurality of modifications shown below can be implemented in combination with each other as appropriate.

(Modification 1)
In the above-described embodiment, when the DSC changeover switch 13 is off and the non-operation of the side slip reduction control is set, compared to when the DSC changeover switch 13 is on and the operation of the side slip reduction control is set. It has been described that the vehicle yaw control is suppressed by increasing the values of both the threshold Y ₁ and the threshold S ₃ or by reducing the yaw moment added by the vehicle yaw control by the gain. The vehicle yaw control may be suppressed by prohibiting the vehicle yaw control when the operation is set.

  With reference to FIG. 8, the attitude | position control process by the modification of embodiment of this invention is demonstrated. FIG. 8 is a flowchart of posture control processing according to a modification of the embodiment of the present invention. Similar to the attitude control process of the embodiment described with reference to FIG. 3, when the attitude control process according to the modification is started, as shown in FIG. 8, in step S <b> 41, the PCM 14 stores various information of the vehicle 1. In step S42, the PCM 14 executes an additional deceleration setting process to set an additional deceleration to be added to the vehicle 1.

  Next, in step S43, the PCM 14 determines whether or not the DSC changeover switch 13 is on based on the information acquired in step S41. As a result, when the DSC changeover switch 13 is on and the operation of the skid reduction control is set, the process proceeds to step S44, and the target yaw moment setting process is executed. In step S45, the PCM 14 controls the engine 2 so as to apply the additional deceleration set in step S42 to the vehicle 1, and applies the target yaw moment set in step 43 to the vehicle 1. The brake device 16 is controlled. Thereafter, the PCM 14 ends the attitude control process.

  On the other hand, if the DSC changeover switch 13 is off and the non-operation of the skid reduction control is set in step S43, the process proceeds to step S45 without executing the target yaw moment setting process in step S44. In this case, the PCM 14 controls the engine 2 so as to add the additional deceleration set in step S42 to the vehicle 1, but since the target yaw moment is not set, the target yaw moment is applied to the vehicle 1. The brake device 16 is not controlled. That is, the vehicle yaw control is substantially prohibited when the DSC changeover switch 13 is off and the non-operation of the skid reduction control is set. This also makes it possible to appropriately suppress the driver from feeling uncomfortable by executing the vehicle yaw control when the non-operation of the skid reduction control is set.

(Modification 2)
In the above-described embodiment, it has been described that the vehicle yaw control is suppressed when the DSC changeover switch 13 is off and the non-operation of the skid reduction control is set. Further, based on the outside air temperature and the lateral acceleration of the vehicle 1, Whether to suppress the vehicle yaw control may be determined. With reference to FIG. 9, the threshold value and gain used in order to set the target yaw moment in the modification of embodiment of this invention are demonstrated concretely. In the table shown in FIG. 9, the magnitude relationship between the threshold value and the gain is defined according to the state of the DSC selector switch 13, the outside air temperature of the vehicle 1, and the lateral acceleration.

Specifically, as shown in FIG. 9, when the DSC selector switch 13 is off and the outside air temperature of the vehicle 1 is equal to or higher than a predetermined value Tt or the lateral acceleration of the vehicle 1 is equal to or higher than Gyt, In other cases (that is, when the DSC changeover switch 13 is on, or when the DSC changeover switch 13 is off but the outside air temperature of the vehicle 1 is less than the predetermined value Tt and the lateral acceleration of the vehicle 1 is less than Gyt. ), Specifically, the threshold value Y ₁ and the threshold value S ₃ are both specified to be large. Note that “when the lateral acceleration of the vehicle 1 is equal to or greater than Gyt” does not necessarily require the lateral acceleration to be equal to or greater than Gyt when setting the threshold and the gain. For example, after the vehicle 1 is turned on and the vehicle starts running, even if the lateral acceleration becomes Gyt or more even once, it is determined that the vehicle 1 falls under “when the lateral acceleration of the vehicle 1 becomes Gyt or more”. Good.

  According to such a threshold value and gain, the DSC changeover switch 13 is off, the non-operation of the skid reduction control is set, and the outside air temperature of the vehicle 1 is equal to or higher than the predetermined value Tt or the lateral acceleration of the vehicle 1 When the value becomes equal to or greater than Gyt, vehicle yaw control is substantially suppressed. As a result, in addition to the non-operation of the skid reduction control being set, when the outside air temperature is relatively high, it is certain that the road surface is not slippery like a snowy road, or the vehicle 1 The vehicle yaw control can be suppressed when it is certain that the driver has intentionally turned off the DSC changeover switch 13 in order to perform sports driving or the like because the lateral acceleration generated in the vehicle is relatively high. Therefore, it is possible to appropriately suppress the driver from feeling uncomfortable by executing the vehicle yaw control when there is a high possibility that the driver does not expect control intervention.

(Modification 3)
In the above-described embodiment, the vehicle yaw control is suppressed by changing both the threshold for determining whether or not to execute the vehicle yaw control and the yaw moment added by the vehicle yaw control (changed by the gain). However, in the modified example, the vehicle yaw control may be suppressed by changing only one of the threshold value and the yaw moment. That is, when the DSC changeover switch 13 is off and the non-operation of the skid reduction control is set, the threshold for determining whether to execute the vehicle yaw control is increased or added by the vehicle yaw control. The yaw moment to be performed may be reduced. This also makes it possible to suppress the vehicle yaw control when the non-operation of the skid reduction control is set.

(Modification 4)
In the embodiment described above, both the target yaw moment setting based on the change rate Δγ ′ of the yaw rate difference (step S35 in FIG. 6) and the target yaw moment setting based on the target lateral jerk (step S38 in FIG. 6) are executed. However, in the modification, only one of these two target yaw moment settings may be executed.

(Modification 5)
In the above-described embodiment, the example in which the rotation angle of the steering column coupled to the steering wheel 6 (the angle detected by the steering angle sensor 8) is used as the steering angle of the vehicle 1 has been described. Instead of the rotation angle or together with the rotation angle of the steering column, various state quantities in the steering system (rotation angle of the motor that applies assist torque, rack displacement in the rack and pinion, etc.) may be used as the steering angle of the vehicle 1. Good.

DESCRIPTION OF SYMBOLS 1 Vehicle 2 Front wheel 4 Engine 6 Steering wheel 8 Steering angle sensor 9 Vehicle speed sensor 10 Acceleration sensor 11 Outside temperature sensor 12 Yaw rate sensor 13 DSC changeover switch 14 PCM
16 Brake device 18 Brake control system

Claims (7)

A steering device, a brake device capable of applying different braking forces to the left and right wheels, a switching device for receiving an operation for setting the operation or non-operation of the side slip reduction control for reducing the side slip of the vehicle, a controller, A vehicle control device comprising:
The controller is
Based on the return operation of the steering device, vehicle yaw control is performed to control the brake device so as to add a yaw moment that is reverse to the yaw rate generated in the vehicle to the vehicle,
The vehicle control device, wherein the vehicle yaw control is suppressed when the non-operation of the skid reduction control is set by the switching device.   The controller is configured to suppress the vehicle yaw control when non-operation of the skid reduction control is set by the switching device and a lateral acceleration of the vehicle becomes a predetermined value or more. The vehicle control device according to claim 1.   3. The controller according to claim 1, wherein the controller is configured to suppress the vehicle yaw control when the non-operation of the skid reduction control is set by the switching device and the outside air temperature is equal to or higher than a predetermined value. The vehicle control device described.   The vehicle control device according to any one of claims 1 to 3, wherein the switching device sets the operation of the skid reduction control when the power of the vehicle is turned on.   The controller performs the vehicle yaw control when a value corresponding to a return operation of the steering device is equal to or greater than a predetermined threshold, and the non-operation of the skid reduction control is set by the switching device The vehicle control device according to any one of claims 1 to 4, wherein the threshold value is configured to be larger than a case where the operation of the side slip reduction control is set.   When the non-operation of the skid reduction control is set by the switching device, the controller adds the yaw moment to be added by the vehicle yaw control more than when the operation of the skid reduction control is set. The vehicle control device according to claim 1, wherein the vehicle control device is configured to be small.   The vehicle according to any one of claims 1 to 4, wherein the controller is configured to prohibit the vehicle yaw control when non-operation of the skid reduction control is set by the switching device. Control device.

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