JP2005145143A - Turn running control device for vehicles - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To perform a more appropriate deceleration control in a scene where a driver performs a steep steering operation. <P>SOLUTION: An automatic deceleration is promoted (at steps S10, S11) by increasing a target deceleration speed Xg* with a correction coefficient K<SB>1</SB>according a fast steering operation when a driver's steep steering operation having a steering angular speed ω exceeding a predetermined value ω<SB>1</SB>is detected (a judgement at the step S9 is "Yes"). <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a turning control device for a vehicle that achieves stable turning.

2. Description of the Related Art Conventionally, there has been a technique in which automatic deceleration is performed so that the turning speed and turning radius of a vehicle do not exceed the limit of turning performance capable of turning stably (see Patent Document 1).
Patent Publication No. 2600876

By the way, when the corner recognition is delayed, the driver tends to perform a sharp steering operation to avoid lane departure. The steeper steering operation is more urgent and the vehicle needs to be decelerated. The nature is also high. However, in the conventional example described in Patent Document 1 described above, since the vehicle deceleration control is performed regardless of whether the steering operation is slow or slow, it is sufficient in a scene where the driver performs a sudden steering operation. There has been a problem that ideal deceleration control cannot be performed because deceleration cannot be performed or the timing of automatic deceleration is delayed.
Accordingly, the present invention has been made paying attention to the above-described problems, and provides a vehicle turning control device that can perform more appropriate deceleration control in a scene where a driver performs a sudden steering operation. It is a problem.

  In order to solve the above-described problems, a vehicle turning control device according to the present invention is characterized in that when a driver's sudden steering operation is detected, deceleration of the host vehicle is promoted.

  According to the turning control device for a vehicle according to the present invention, when the driver's sudden steering operation is detected, the driver's sudden steering operation is promoted by facilitating the deceleration of the host vehicle, so that the driver can steer quickly in an emergency such as a lane departure. When performing the operation, it is possible to perform appropriate deceleration control while avoiding insufficient deceleration or delay.

Hereinafter, the best mode for carrying out the present invention will be described with reference to the drawings.
FIG. 1 is a block diagram showing a schematic configuration of the present invention. An electromagnetic induction wheel speed sensor 1 for detecting the wheel speed Vwi (i = FL to RR) of each wheel, an acceleration sensor 2 for detecting the longitudinal acceleration Xg and the lateral acceleration Yg of the vehicle body using, for example, a mercury switch, and steering The optical / non-contact type steering angle sensor 4 that detects the steering angle θ of the wheel 3 is connected to the controller 5.

The controller 5 is composed of, for example, a microcomputer, and executes a turning traveling control process, which will be described later, based on detection signals from the respective sensors, and drives and controls the braking force control device 6 and the engine output control device 7. Automatic deceleration is performed according to the turning state.
Here, the braking force control device 6 uses a braking fluid pressure control circuit used for anti-skid control (ABS), traction control (TCS), stability control (VDC), etc., as shown in FIG. Further, it is interposed between the master cylinder 8 and each wheel cylinder 9i so that the brake fluid pressure of each wheel cylinder 9i can be increased, held and reduced regardless of the driver's braking operation.

  First, the master cylinder 8 is connected to the front left and rear right wheel cylinders 9FL and 9RR via a normally open type switching valve 10A and a normally open type inlet solenoid valve 11FL and 11RR, and is also normally open. It is connected to the front right and rear left wheel cylinders 9FR and 9RL via the type switching valve 10B and the normally open type inlet solenoid valves 11FR and 11RL.

Each of the inlet solenoid valves 11i is provided with a return check valve 12i that bypasses the orifice when the brake is released and returns the brake fluid pressure of each wheel cylinder 9i to the master cylinder 8.
Further, the master cylinder 8 is connected to the downstream side (wheel cylinder side) of the switching valve 10A via a normally closed switching valve 13A and is connected to the switching valve 10B via a normally closed switching valve 13B. It is connected to the downstream side (wheel cylinder side), and is driven by the electric motor 14 between the switching control valves 10A and 13A and between the switching control valves 10B and 13B, and the switching valves 13A and 13B side. A common pump 15 is interposed between the suction side and the suction side.

The inlet side of the pump 15 is provided with an inlet valve 16 for preventing the backflow of the fluid to be sucked. The outlet side of the pump 15 is provided with an outlet valve 17 for preventing the backflow of the fluid to be discharged, and the pump 15 discharges. A damper chamber 18 that suppresses the pulsation of the hydraulic pressure is provided.
The front left and rear right wheel cylinders 9FL and 9RR are connected to the downstream side (pump side) of the switching valve 13A via normally closed outlet solenoid valves 19FL and 19RR, and the front right and rear left wheels are connected. The cylinders 9FR and 9RL are connected to the downstream side (pump side) of the switching valve 13B via normally closed outlet solenoid valves 19FR and 19RL.

At the upstream side of the outlet solenoid valves 19FL and 19RR (the switching valve 13A side) and the upstream side of the outlet solenoid valves 19FR and 19RL (the switching valve 13B side), this pressure reduction is efficiently performed when each wheel cylinder 9i is decompressed. For this purpose, a reservoir 20 for temporarily storing the brake fluid pressure from the wheel cylinder 9i is provided.
As described above, the braking force control device 6 can be used for a driver's brake operation when the switching valves 10A and 10B, the switching valves 13A and 13B, the inlet solenoid valve 11i, and the outlet solenoid valve 19i are in a non-energized state. The corresponding normal braking fluid pressure is supplied to each wheel cylinder 9i through the switching valves 10A and 10B and the inlet solenoid valve 11i.

Further, when the switching valves 10A and 10B and the switching valves 13A and 13B are energized and the pump 15 is operated, the master cylinder 8 can be connected via the switching valves 13A and 13B regardless of the driver's brake operation. The sucked brake fluid pressure is supplied to each wheel cylinder 9i through the inlet solenoid valve 11i, and the pressure is increased.
Further, when the switching valves 10A and 10B and the inlet solenoid valve 11i are energized, the wheel cylinders 9i, the pump 15, and the reservoir 20 are shut off, and the brake fluid pressure of the wheel cylinders 9i is maintained.

Further, when the switching valves 10A and 10B, the inlet solenoid valve 11i, and the outlet solenoid valve 19i are energized and the pump 15 is operated, the brake fluid pressure of each wheel cylinder 9i is sucked out to the reservoir 20 side. The pressure is reduced.
Therefore, the controller 5 controls the energization of the switching valves 10A and 10B, the switching valves 13A and 13B, the inlet solenoid valve 11i, and the outlet solenoid valve 19i, respectively, and controls the driving of the pump 15. The brake fluid pressure in each wheel cylinder 9i can be increased, held, and reduced.

The engine output control device 7 in FIG. 1 is configured to control the engine output, for example, by adjusting the opening of the throttle valve.
Next, a first embodiment of the turning control process executed by the controller 5 will be described based on the flowchart of FIG.
This turning traveling control process is executed as a timer interruption process every predetermined time (for example, 10 msec). As shown in FIG. 3, first, in step S1, each wheel speed Vwi, longitudinal acceleration Xg, lateral acceleration Yg, steering Read the angle θ.
In the subsequent step S2, the steering angle θ is differentiated to calculate the steering angular velocity ω (operation speed). In the present embodiment, the steering angular velocity ω is calculated by differentiating the steering angle θ. However, the present invention is not limited to this, and a tachometer or the like is attached to the rotating shaft of the steering wheel 3 to rotate directly. The speed may be detected.

In the subsequent step S3, the vehicle body speed V is calculated based on each wheel speed Vwi and the longitudinal acceleration Xg.
In the subsequent step S4, the current vehicle turning radius R is calculated from the vehicle body speed (hereinafter referred to as the turning speed) V and the lateral acceleration Yg according to the following equation (1). In this embodiment, the turning radius R is simply calculated using the turning speed V and the lateral acceleration Yg. However, the present invention is not limited to this, and the steering angle θ and the yaw angular acceleration are improved to improve accuracy. Or the like may be used to calculate the turning radius R.
^{R = V 2 / Yg ......... (} 1)

In the subsequent step S5, a deceleration start threshold Rs for the turning radius R is set. First, a limit turning radius _RL that can be stably turned with respect to the current turning speed V is calculated according to the following equation (2). Here, Yg _L is an actual limit lateral acceleration at which the vehicle can turn stably, and is determined by the specifications of the vehicle, but is changed according to the slip ratio Si of each wheel obtained from each wheel speed Vwi and the turn speed V. Also good.
R _L = V ² / Yg _L (2)

Then, as shown in the following equation (3), a deceleration start threshold Rs is set by multiplying the above limit turning radius _RL by a predetermined value h (for example, h = 1.1) larger than 1. Here, the deceleration start threshold Rs is set to be larger than the limit turning speed _RL before the turning radius R reaches the limit turning radius _RL , that is, before the tire grip force is saturated. This is to start automatic deceleration.
Rs = h · R _L (3)

In the subsequent step S6, a deceleration start threshold Vs for the turning speed V is set. First, a limit turning speed _VL that can be stably turned with respect to the current turning radius R is calculated according to the following equation (4).
V _L = √ (R · Yg _L ) (4)
Then, as shown in the following equation (5), the deceleration start threshold Vs is set by multiplying the limit turning speed V _L by a predetermined value k (for example, k = 0.9) smaller than 1. Here, the deceleration start threshold Vs of is set smaller than the limit turning velocity V _L, before turning velocity V reaches a limit turning velocity V _L, i.e. before the tire grip force is saturated This is to start automatic deceleration.
Vs = k · R _L (5)

  In the subsequent step S7, it is determined whether or not the current turning radius R is smaller than the deceleration start threshold value Rs, and whether or not the current turning speed V is larger than the deceleration start threshold value Vs. When this determination result is R ≧ Rs and V ≦ Vs, it is determined that the turning state of the vehicle is not approaching the limit of the turning performance and automatic deceleration is unnecessary, and the process returns to the predetermined main program. . On the other hand, when the determination result is R <Rs or V> Vs, it is determined that the turning state of the vehicle is approaching the limit of the turning performance and automatic deceleration is necessary, and the process proceeds to step S8.

In step S8, the target deceleration Xg ^* is calculated according to the deviation between the turning radius R and the deceleration start threshold Rs and the deviation between the turning speed V and the deceleration start threshold Vs.
In step S9, the steering angular velocity omega is equal to or a predetermined value omega ₁ or more. The predetermined value ω ₁ is a steering angular velocity when the driver performs a sudden steering operation in an emergency such as lane departure. Then, when the judgment result is omega <omega ₁ determines that it is not the sudden steering operation, the process proceeds to step S12 to be described later. On the other hand, when the determination result is omega ≧ omega ₁ is determined to be a steep steering operation, the process proceeds to step S10.

In step S10, with reference to the control map as shown in the flowchart, the correction factor K ₁ for multiplying the target deceleration Xg ^*, is calculated in accordance with the steering angular velocity omega. Configuration The control map, the horizontal axis steering angular velocity omega, and the vertical axis represents the correction factor K _1, as the steering angular velocity omega is enough to increase from the predetermined value omega ₁ described above, the correction factor K ₁ is increased from 1 Has been.
In step S11, the multiplying the correction coefficient K ₁ calculated for target deceleration Xg ^* in step S8, the process proceeds from the corrected target deceleration Xg ^* to step S12.

In step S12, it calculates a target brake fluid pressure Pi ^* of the respective wheel cylinders 13i needed to achieve the target deceleration Xg ^*.
In the following step S13, the braking force control device 6 is driven and controlled so that the braking fluid pressure of each wheel cylinder 9i matches the target braking fluid pressure Pi ^* .
In the subsequent step S14, the engine output control device 7 is driven and controlled so as to obtain an optimum engine output in order to achieve the target deceleration Xg ^* by the braking force control device 6, and then returned to a predetermined main program.

Here, the processing of steps S2 and S9 corresponds to the sudden operation detecting means, the processing of steps S3 and S4 corresponds to the turning state detecting means, the processing of steps S5 to S8, S10 to S14, the braking force control device 6 and The engine output control device 7 corresponds to the travel control means.
Next, operations and effects of the first embodiment will be described.
Now assume that the vehicle is turning at a certain speed. At this time, when the turning radius R is equal to or greater than the deceleration start threshold value Rs and the turning speed V is equal to or less than the deceleration start threshold value Vs (determination in step S7 is “No”), stable turning traveling is maintained. Judge that there is no need for deceleration. Therefore, the braking force control device 6 is controlled so that the normal braking fluid pressure corresponding to the driver's braking operation is supplied to each wheel cylinder 9i.

From this state, when the driver's steering operation amount increases and the turning radius R falls below the deceleration start threshold value Rs, or when the driver's accelerator operation amount increases and the turning speed V exceeds the deceleration start threshold value Vs. ("Yes" in step S7), it is determined that automatic deceleration is required because the turning state of the vehicle is approaching the limit of turning performance.
Then, the target deceleration Xg ^* corresponding to the deviation between the turning radius R and the deceleration start threshold Rs and the deviation between the turning speed V and the deceleration start threshold Vs is calculated (step S8), and this target deceleration Xg ^* is achieved. For this purpose, the hydraulic pressure in each wheel cylinder 13i is increased and the engine output is suppressed to perform automatic deceleration (steps S12 to S14) to achieve stable turning.

Thus, the automatic deceleration is terminated when the vehicle can return to the stable turning state by the automatic deceleration, that is, when the turning radius R is equal to or higher than the deceleration start threshold value Rs and the turning speed V is equal to or lower than the deceleration start threshold value Vs.
By the way, as shown in FIG. 4, when the driver suddenly performs a steering operation, for example, to avoid lane departure, at time t ₁ , the steering angle θ increases greatly, so the deceleration start threshold Vs for the turning speed V is Decrease significantly. Thereafter, when at time t ₂ turning speed V is greater than the deceleration start threshold Vs, but turning velocity V automatic deceleration is started begins to decrease, this time, as the driver's steering operation is rapid, urgency High and the need for vehicle deceleration is high.

Therefore, in the present embodiment, when a sudden steering operation in which the steering angular velocity ω exceeds the predetermined value ω ₁ is detected (determination in Step S9 is “Yes”), the target deceleration Xg ^* is corrected as the steering operation becomes steeper. The automatic deceleration is promoted by increasing the coefficient K ₁ (steps S10 and S11). As a result, when the driver performs a sudden steering operation in an emergency such as a lane departure, the vehicle can be sufficiently decelerated, and safety is improved.
In the present embodiment, since the steering angular velocity ω is calculated, it is possible to easily detect a driver's sudden steering operation.
In the first embodiment, the target deceleration Xg ^* is increased by multiplication of the correction coefficient K _1. However, the present invention is not limited to this, and the target deceleration Xg ^* is increased by adding the correction coefficient K ₁ ^. May be increased.

In the first embodiment described above, it is determined whether or not ω ≧ ω ₁ in step S9, and then the correction coefficient K ₁ is calculated and the target deceleration Xg ^* is corrected. It is not limited. For example, in the control map referred to in step S10, when the steering angular velocity ω is less than the predetermined value ω ₁ , the correction factor K ₁ is maintained at 1, and when the steering angular velocity ω increases from the predetermined value ω ₁ , the correction factor is corrected. By setting K ₁ to increase from _1, the process of step S9 may be omitted. In this case, the processing in step S2 and the control map referred to in step S10 correspond to the sudden operation detection means.
In the first embodiment, the driver's sudden steering operation is detected according to the steering angular velocity ω. However, the present invention is not limited to this, and the driver's sudden steering operation is detected according to the acceleration of the steering angular velocity ω. A sudden steering operation may be detected.

Next, a second embodiment of the present invention will be described with reference to FIG.
In the second embodiment, the driver's sudden steering operation is detected not based on the steering angular velocity ω but on the average steering angular velocity ωa within a predetermined time.
That is, in the turning traveling control process of the second embodiment, as shown in FIG. 5, the steps S2 and S9 to S11 in FIG. 3 are changed to new steps S20 and S21 to S23, respectively. The same process as the turning traveling control process 3 is executed. 3 corresponding to those in FIG. 3 are denoted by the same reference numerals, and detailed description thereof is omitted.
First, in step S20, an average steering angular speed ωa (average operating speed) of the steering angular speed ω within a predetermined time is calculated. This predetermined time is a time necessary to distinguish between a case where the driver performs a steering operation quickly and in small increments and a case where the driver performs a sudden steering operation in an emergency such as a lane departure.

Further, in step S21, the average steering angular speed ωa is equal to or a predetermined value omega ₂ or more. The predetermined value ω ₂ is a steering angular velocity when the driver performs a sudden steering operation in an emergency such as a lane departure. Then, when the judgment result is .omega.a <omega ₂ determines that it is not the sudden steering operation, the process proceeds to step S12. On the other hand, when the determination result is .omega.a ≧ omega ₂ is determined to be a steep steering operation, the process proceeds to step S22.

In step S22, with reference to the control map as shown in the flowchart, the correction factor K ₂ which multiply the target deceleration Xg ^*, is calculated according to the average steering angular speed .omega.a. Here, the control map, the horizontal axis average steering angular speed .omega.a, the vertical axis represents the correction factor K _2, the average higher steering angular .omega.a increases from the predetermined value omega ₂ described above, so that the correction factor K ₂ is increased from 1 Is set to
In step S23, the multiplying the correction coefficient K ₂ to the calculated target deceleration Xg ^* in step S8, the process proceeds from the corrected target deceleration Xg ^* to the step S12.
Here, the processes of steps S20 and S21 correspond to the sudden operation detecting means, and the processes of steps S22 and S23 constitute a part of the travel control means.
Next, operations and effects of the second embodiment will be described.

Now, assume that the turning state of the vehicle is approaching the limit of turning performance and it is determined that automatic deceleration is required. Here, if a driver's sudden steering operation in which the average steering angular velocity ωa exceeds the predetermined value ω ₂ is detected (determination in Step S21 is “Yes”), the target deceleration Xg ^* is corrected as the steering operation becomes steeper. It is increased by the coefficient K ₂ to promote automatic deceleration (steps S22 and S23). Thus, when the driver performs a sudden steering operation in an emergency such as a lane departure, the vehicle can be sufficiently decelerated and safety is improved.

In addition, in the present embodiment, by detecting the average steering angular velocity ωa within a predetermined time, the driver performs the steering operation quickly in small increments, and the driver performs the steering operation suddenly in an emergency such as lane departure. The deceleration control can be performed in distinction from the case. That is, when the driver is performing the steering operation quickly and in small increments, the vehicle can be prevented from being decelerated more than necessary, and the driver does not feel uncomfortable.
Other functions and effects are the same as those of the first embodiment described above.
In the second embodiment, the target deceleration Xg ^* is increased by multiplication of the correction coefficient K _2. However, the present invention is not limited to this, and the target deceleration Xg ^* is increased by adding the correction coefficient K ₂ ^. May be increased.

In the second embodiment, it is determined whether or not ωa ≧ ω ₂ in step S21, and then the correction coefficient K ₂ is calculated and the target deceleration Xg ^* is corrected. It is not limited. For example, in the control map referred to in step S22, when the average steering angular velocity ωa is less than the predetermined value ω ₂ , the correction coefficient K ₂ is maintained at 1, and the average steering angular velocity ωa increases from the predetermined value ω _2. By setting the correction coefficient K ₂ to increase from 1, the process of step S21 may be omitted. In this case, the process in step S20 and the control map referred to in step S22 correspond to the sudden operation detection means.
In the second embodiment, the driver's sudden steering operation is detected according to the average steering angular velocity ωa. However, the present invention is not limited to this, and the average acceleration of the steering angular velocity ω within a predetermined time is detected. Accordingly, the driver's sudden steering operation may be detected.

Next, a third embodiment of the present invention will be described with reference to FIG.
In the third embodiment, the target deceleration Xg ^* is increased based on the average steering angular velocity ωa and the steering angular velocity ω.
That is, in the turning control process of the third embodiment, as shown in FIG. 6, the step S2 is added before the step S20 of FIG. 5, and the processes of the steps S21 to S23 are replaced with new steps S30 to S32. A process similar to the turning control process shown in FIG. Note that portions corresponding to those in FIG. 5 are denoted by the same reference numerals, and detailed description thereof is omitted.

First, in step S30, a correction map K ₂ is calculated according to the average steering angular velocity ωa with reference to a control map as shown in the flowchart. Here, the control map, the horizontal axis average steering angular speed .omega.a, the vertical axis represents the correction factor K _2, when the average steering angular speed .omega.a is equal to or less than the predetermined value omega ₂ described above, the correction factor K ₂ is maintained 1 The correction coefficient K ₂ is set to increase from 1 when the average steering acceleration ωa increases from the predetermined value ω ₂ .

In the subsequent step S31, a correction map K ₁ 'is calculated according to the steering angular velocity ω with reference to a control map as shown in the flowchart. Here, in the control map, the horizontal axis represents the steering angular velocity ω, the vertical axis represents the correction coefficient K ₁ ′, and when the steering angular speed ω increases from 0, the correction coefficient K ₁ ′ increases after maintaining 0 for a while. Is set to start.
In step S32, the above correction factor K ₂ and the correction factor K ₁ 'and a value obtained by adding the (K ₂ + K _1' to), multiplied by the calculated target deceleration Xg ^* in the step S8, the target deceleration Xg After correcting ^* , the process proceeds to step S12.

Here, the control map referred to in steps S30 and S31 constitutes a part of the sudden operation detection means, and the processes in steps S30 to S32 constitute a part of the travel control means.
Next, operations and effects of the third embodiment will be described.
Now, assume that the turning state of the vehicle is approaching the limit of turning performance and it is determined that automatic deceleration is required. Here, as the average steering angular velocity ωa and the steering angular velocity ω are larger, the target deceleration Xg ^* is increased by the correction coefficient K ₂ and the correction coefficient K ₁ ′ to promote automatic deceleration (steps S30 to S32).

At this time, in the present embodiment, when the steering angular velocity ω is relatively small, the correction coefficient K ₁ ′ is set near 0, so that the same effect as that of the second embodiment described above can be obtained. Further, when the steering angular velocity ω becomes excessively large, the correction coefficient K ₁ ′ starts to increase from around 0, so that the target deceleration Xg ^* is increased by both the correction coefficient K ₁ ′ and the correction coefficient K _2. The vehicle can be further decelerated in a scene where the necessity of vehicle deceleration is higher.
Other functions and effects are the same as those of the first and second embodiments described above.

Next, a fourth embodiment of the present invention will be described with reference to FIGS.
The fourth embodiment does not increase the deceleration amount due to automatic deceleration as the steering angular velocity ω increases as in the first embodiment described above, but makes it easier for the automatic deceleration to start as the steering angular velocity ω increases. Is.
That is, in the turning control process of the fourth embodiment, as shown in FIG. 7, the processes of steps S2, S9 to S11 of FIG. 3 are deleted, and new steps S40 to S7 are performed between steps S6 and S7. Except for the addition of the process of S42, the same process as the turning control process of FIG. 3 is executed. 3 corresponding to those in FIG. 3 are denoted by the same reference numerals, and detailed description thereof is omitted.

First, in step S40, it is determined whether or not the steering angular velocity ω is equal to or greater than a predetermined value ω ₃ . The predetermined value ω ₃ is a steering angular velocity when the driver performs a sudden steering operation in an emergency such as a lane departure. When the determination result is ω <ω _3, it is determined that the steering operation is not abrupt, and the process proceeds to step S7. On the other hand, when the determination result is ω ≧ ω ₃ , it is determined that the steering operation is abrupt, and the process proceeds to step S41.

In step S41, a control map as shown in the flowchart is referred to, and a correction coefficient K _R1 multiplied by the deceleration start threshold Rs and a correction coefficient K _V1 multiplied by the deceleration start threshold Vs are calculated according to the steering angular velocity ω. . Here, in the control map, the horizontal axis indicates the steering angular velocity ω, the vertical axis indicates the correction coefficient K, and the correction coefficient K _R1 for Rs increases from 1 as the steering angular speed ω increases from the predetermined value ω ₃ described above. , Vs correction coefficient K _V1 is set to decrease from 1.

In subsequent step S42, the deceleration start threshold value Rs calculated in step S5 is multiplied by the correction coefficient K _R1 , and the deceleration start threshold value Vs calculated in step S6 is multiplied by the correction coefficient K _V1. Is corrected, and then the process proceeds to step S7.
Here, the process of step S40 constitutes a part of the sudden operation detection means, and the processes of steps S41 and S42 constitute a part of the travel control means.

Next, operations and effects of the fourth embodiment will be described.
Now, as shown in FIG. 8, if the driver performs a sudden steering operation at time t ₃ , the steering angle θ greatly increases, so the deceleration start threshold Vs with respect to the turning speed V greatly decreases. Thereafter, when the turning speed V becomes greater than the deceleration start threshold Vs, automatic deceleration is started. However, the steeper the steering operation by the driver is, the higher the urgency is and the greater the need for vehicle deceleration is.

Therefore, in the present embodiment, when a sudden steering operation in which the steering angular velocity ω exceeds the predetermined value ω ₃ is detected (determination in step S40 is “Yes”), the deceleration start threshold Rs is set so that automatic deceleration is easily started. Automatic deceleration is promoted by setting a large value by the correction coefficient K _R1 and setting a deceleration start threshold value Vs by a small correction coefficient K _V1 (steps S41 and S42). As a result, when the driver performs a sudden steering operation in an emergency such as a lane departure, the timing of automatic deceleration is advanced, so that the vehicle can be decelerated quickly and safety is improved.

Other functions and effects are the same as those of the first embodiment described above.
In the fourth embodiment, the deceleration start threshold Rs is increased by multiplying the correction coefficient K _{R1 and} the deceleration start threshold Vs is decreased by multiplying the correction coefficient K _V1 . However, the present invention is not limited to this. Alternatively, the deceleration start threshold value Rs may be increased by adding the correction coefficient K _R1 , and the deceleration start threshold value Vs may be decreased by subtracting the correction coefficient K _V1 .

In the fourth embodiment, after determining whether or not ω ≧ ω ₃ in step S40, the correction coefficient K _R1 and the correction coefficient K _V1 are calculated, and the deceleration start threshold values Rs and Vs are corrected. However, it is not limited to this. For example, in the control map referred to in step S41, when the steering angular velocity ω is less than the predetermined value ω ₃ , both the correction coefficients K _R1 and K _V1 are maintained at 1, and the steering angular velocity ω increases from the predetermined value ω ₃ . The processing in step S40 may be omitted by setting the correction coefficient K _R1 for Rs to increase from 1 and the correction coefficient K _V1 for Vs to decrease from 1. In this case, the processing in step S2 and the control map referred to in step S41 correspond to the sudden operation detection means.

In the fourth embodiment, the deceleration start thresholds Rs and Vs are corrected using the correction coefficients K _R1 and K _V1 . However, the present invention is not limited to this. In short, it is only necessary to correct the deceleration start thresholds Rs and Vs so that the more rapid the steering operation is, the easier it is to start the automatic deceleration. Therefore, the constants used to calculate the deceleration start thresholds Rs and Vs (limit lateral acceleration Yg _L Alternatively, the deceleration start threshold values Rs and Vs may be corrected by changing the predetermined values h and k).

Next, a fifth embodiment of the present invention will be described with reference to FIG.
In the fifth embodiment, not the steering angular velocity ω but the average steering angular velocity ωa within a predetermined time is detected to detect the driver's sudden steering operation in the fourth embodiment described above.
That is, in the turning travel control process of the fifth embodiment, as shown in FIG. 9, the process of step S2 of FIG. 7 is changed to the process of step S20, and the process of steps S40 to S42 is a new step. Except having changed to S50-S52, the process similar to the turning control process of FIG. 7 is performed. Note that portions corresponding to those in FIG. 7 are assigned the same reference numerals, and detailed descriptions thereof are omitted.

First, at step S50, the average steering angular speed ωa is equal to or a predetermined value omega ₄ or more. The predetermined value ω ₄ is a steering angular velocity when the driver performs a sudden steering operation in an emergency such as lane departure. When the determination result is ω <ω _4, it is determined that the steering operation is not abrupt, and the process proceeds to step S7. On the other hand, when the determination result is ω ≧ ω ₄ , it is determined that the steering operation is abrupt, and the process proceeds to step S51.

In step S51, a control map as shown in the flowchart is referred to, and a correction coefficient K _R2 multiplied by the deceleration start threshold Rs and a correction coefficient K _V2 multiplied by the deceleration start threshold Vs are calculated according to the average steering angular velocity ωa. To do. Here, in the control map, the horizontal axis is the average steering angular velocity ωa, the vertical axis is the correction coefficient K, and the correction coefficient K _R2 for Rs increases from 1 as the average steering angular speed ωa increases from the predetermined value ω ₄ described above. In addition, the correction coefficient K _V2 for Vs is set to decrease from 1.

In the subsequent step S52, the deceleration start threshold Rs calculated in step S5 is multiplied by the correction coefficient K _R2 , and the deceleration start threshold Vs calculated in step S6 is multiplied by the correction coefficient K _V2 to obtain the deceleration start thresholds Rs and Vs. Is corrected, and then the process proceeds to step S7.
Here, the process of step S50 constitutes a part of the sudden operation detection means, and the processes of steps S51 and S52 constitute a part of the travel control means.

Next, operations and effects of the fifth embodiment will be described.
Now, the average steering angular speed ωa is to detects an abrupt steering operation exceeding a predetermined value omega ₄ (the determination in step S50 is "Yes"). Therefore, the deceleration start threshold Rs is set to be large by the correction coefficient K _R2 and the deceleration start threshold Vs is set to be small by the correction coefficient K _V2 so that automatic deceleration is easily started, thereby promoting the automatic deceleration (step S51). , S52). As a result, when the driver performs a sudden steering operation in an emergency such as a lane departure, the timing of automatic deceleration is advanced, so that the vehicle can be decelerated quickly and safety is improved.

  In addition, in the present embodiment, by detecting the average steering angular velocity ωa within a predetermined time, the driver performs the steering operation quickly in small increments, and the driver performs the steering operation suddenly in an emergency such as lane departure. The deceleration control can be performed in distinction from the case. That is, when the driver is performing the steering operation quickly and in small increments, the vehicle can be prevented from being decelerated more than necessary, and the driver does not feel uncomfortable.

Other functions and effects are the same as those of the fourth embodiment described above.
In the fifth embodiment, the deceleration start threshold value Rs is increased by multiplying the correction coefficient K _{R2 and} the deceleration start threshold value Vs is decreased by multiplying the correction coefficient K _V2 . However, the present invention is not limited to this. Alternatively, the deceleration start threshold value Rs may be increased by adding the correction coefficient K _R2 , and the deceleration start threshold value Vs may be decreased by subtracting the correction coefficient K _V2 .

In the fifth embodiment, it is determined whether or not ω ≧ ω ₄ in step S50, and then the correction coefficient K _R2 and the correction coefficient K _V2 are calculated, and the deceleration start threshold values Rs and Vs are corrected. However, it is not limited to this. For example, in the control map referred to in step S51, when the steering angular velocity ω is less than the predetermined value ω ₄ , both the correction coefficients K _R2 and K _V2 maintain 1, and the steering angular velocity ω increases from the predetermined value ω ₄ . The processing of step S50 may be omitted by setting the correction coefficient K _R2 for Rs to increase from 1 and the correction coefficient K _V2 for Vs to decrease from 1. In this case, the process in step S20 and the control map referred to in step S51 correspond to the sudden operation detection unit.

Next, a sixth embodiment of the present invention will be described with reference to FIGS.
In the sixth embodiment, the first embodiment and the fourth embodiment described above are merged, and as the driver's steering operation is steeper, the automatic deceleration is more easily started and the automatic deceleration is performed. The amount of deceleration is increased.
That is, in the sixth embodiment, as shown in FIG. 10, except that the processing of steps S40 to S42 of FIG. 9 is added between steps S6 and S7 of FIG. A process similar to the turning control process is executed. 3 corresponding to those in FIG. 3 are denoted by the same reference numerals, and detailed description thereof is omitted.

Therefore, as shown in FIG. 11, when the driver performs a sudden steering operation at time t ₄ and the steering angular velocity ω exceeds the predetermined value ω ₃ (determination in step S40 is “Yes”), the deceleration start threshold Rs. And Vs are set so that the automatic deceleration is easily started, and the automatic deceleration is promoted (steps S41 and S42).
Further, at a later point in time t _5, when the turning speed V is larger than deceleration-start threshold Vs, and starts the automatic deceleration, when the steering angular velocity omega of this time is not greater than the predetermined value omega ₁ (determination of step S9 is " Yes "), the target deceleration Xg ^* is increased to promote automatic deceleration (steps S10 and S11).

As a result, when the driver suddenly performs a steering operation in an emergency such as a lane departure, the vehicle can be decelerated quickly and sufficiently, and safety is improved.
Other functions and effects are the same as those of the first and fourth embodiments described above.
In the sixth embodiment, the deceleration start thresholds Rs and Vs are increased based on the steering angular velocity ω. However, the present invention is not limited to this, and the average steering angular velocity is the same as in the fifth embodiment described above. The deceleration start thresholds Rs and Vs may be increased based on ωa.

In the sixth embodiment, the target deceleration Xg ^* is increased based on the steering angular velocity ω, but the present invention is not limited to this. That is, the target deceleration Xg ^* is increased based on the average steering angular velocity ωa as in the second embodiment, or based on the steering angular velocity ω and the average steering angular velocity ωa as in the third embodiment. The target deceleration Xg ^* may be increased.

It is a block diagram which shows schematic structure of this invention. It is a hydraulic circuit diagram of a braking force control device. It is a flowchart which shows the turning traveling control process of 1st Embodiment. It is a time chart explaining the effect of a 1st embodiment. It is a flowchart which shows the turning traveling control process of 2nd Embodiment. It is a flowchart which shows the turning traveling control process of 3rd Embodiment. It is a flowchart which shows the turning traveling control process of 4th Embodiment. It is a time chart explaining the effect of a 4th embodiment. It is a flowchart which shows the turning traveling control process of 5th Embodiment. It is a flowchart which shows the turning traveling control process of 6th Embodiment. It is a time chart explaining the effect of a 6th embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Wheel speed sensor 2 Acceleration sensor 3 Steering wheel 4 Steering angle sensor 5 Controller 6 Braking force control device 7 Engine output control device 9FL to 9RR Wheel cylinder 10A / 10B Switching valve 11FL to 11RR Inlet solenoid valve 13A / 13B Switching valve 14 Electric motor 15 Pump 19FL-19RR Outlet solenoid valve 20 Reservoir

Claims (5)

A turning state detection means for detecting a turning state of the host vehicle, and a traveling control means for decelerating the host vehicle when the turning state detected by the turning state detection means exceeds a deceleration start threshold. In the control device,
Equipped with sudden operation detection means to detect the driver's sudden steering operation,
The vehicle travel control device, wherein the travel control means promotes the deceleration of the host vehicle when the sudden operation detection means detects a driver's sudden steering operation.   When the sudden operation detection unit detects a sudden steering operation of the driver, the travel control unit increases the deceleration amount when decelerating the host vehicle as the steering operation is sudden. The turning control device for a vehicle according to claim 1, wherein the vehicle deceleration is accelerated.   When the sudden operation detecting unit detects a driver's sudden steering operation, the travel control unit sets the deceleration start threshold value so that the deceleration of the host vehicle is more likely to start as the steering operation is sudden. 3. The turning control device for a vehicle according to claim 1 or 2, wherein the deceleration of the host vehicle is promoted by setting to.   The said sudden operation detection means detects that it is a driver | operator's sudden steering operation, when the operation speed of steering operation exceeds predetermined value, The one of Claims 1-3 characterized by the above-mentioned. Vehicle turning control device.   5. The sudden operation detecting means detects that the driver is performing an abrupt steering operation when an average speed of the steering operation within a predetermined time exceeds a predetermined value. The turning control device for a vehicle according to one item.

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