JPH07251754A - Control device for travel of vehicle - Google Patents

Abstract

PURPOSE:To prevent the driver's control of a steering wheel from interfering with turning of the steering wheel by automatic steering by setting main steered wheels which are connected to the steering wheel and auxiliary steered wheels which are steered solely by the driving of an actuator, and preferring operation of the auxiliary steered wheels when an automatic steering system intervenes. CONSTITUTION:During automatic steering, rear wheels W3, W4 (auxiliary steered wheels) which are steered only by a rear-wheel actuator independently of a steering wheel 12 are preferred for operation. As a result, the driver's control of the steering wheel does not interfere with the turning of the steering wheel by the automatic steering, so as not to disturb the driver. In particular, the maximum amount of steering of the rear wheels W3, W4 is set as being smaller than that of the front wheels W1, W2 (main steered wheels) by a given amount, and the rear wheels W3, W4 whose amount of steering is small are automatically steered for correction while the vehicle is unlikely to run off course. When the vehicle is highly likely to run off course, the front wheels W1, W2 are also automatically steered by a front-wheel actuator.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle running control device, and more particularly to a vehicle running control system, in which a driver basically operates a vehicle to avoid a risk of collision or to prevent deviation from a running lane. The present invention relates to a vehicle travel control device that allows an automatic steering system to intervene only in the case of.

[0002]

2. Description of the Related Art Conventionally, a so-called automatic steering system, which is a traveling control device for a vehicle such as an automobile, is known so as to automatically perform steering to some extent automatically while the vehicle is traveling. It is considered to be applied to a collision avoidance system for avoiding a collision with a vehicle or another moving body, a so-called key plane system for maintaining traveling along a predetermined traveling lane, or the like.

For example, in Japanese Unexamined Patent Publication No. 1-124008, the movement specifications of the opponent moving body are detected using a laser beam, and the collision position is determined from the movement specifications of the opponent moving body and the movement specifications of the own vehicle. By calculating and determining a collision avoidance route according to a predetermined avoidance rule and performing automatic steering so that the vehicle moves on this avoidance route, it is possible to avoid collision of multiple moving bodies at high speed. Things are disclosed. Also,
For example, in Japanese Unexamined Patent Publication No. H5-50931, in an automatic steering device that automatically performs steering for avoiding interference with an obstacle, a steering wheel is operated while the steering angle of a wheel is interlocked with the steering angle of a wheel during automatic steering. By providing a delay means that delays the start-up of the steering angle later than that of the wheel turning angle, the so-called kickback-like element that may hurt the driver is alleviated and proper automatic steering without giving the driver a feeling of discomfort. It is disclosed that the above can be performed.

[0004]

SUMMARY OF THE INVENTION The above-described automatic steering system, for example, avoids this danger when a predetermined dangerous state is detected while the vehicle is traveling, or tends to deviate from a predetermined traveling lane. In this case, in order to prevent this deviation, the steering is automatically steered, and the steering is generally sudden. That is, during the intervention of the automatic steering, the steering wheel suddenly rotates regardless of the driver's intention. In this case, in the case of a so-called autonomous vehicle in which the steering steering is completely automated, the driver normally releases his / her hand from the steering wheel, so that there is a sudden turning operation of the steering wheel due to automatic steering. However, it is not particularly affected. However, basically, in a system in which the automatic steering intervention is performed only in a predetermined case, such as when the driver performs a driving operation to avoid the risk of collision or to prevent deviation from the driving lane, There is a problem in that the steering wheel operation and the sudden turning movement of the steering wheel due to automatic steering interfere with each other, and the driver feels uncomfortable.

The present invention has been made in view of the above problems. Basically, a driver performs a predetermined driving operation to avoid a danger of collision or prevent deviation from a driving lane. In the vehicle travel control device that allows the automatic steering system to intervene only in the case,
The basic purpose is to eliminate the interference between the driver's steering wheel operation and the steering wheel turning operation by automatic steering.

[0006]

Therefore, the invention according to claim 1 of the present application (hereinafter, referred to as the first invention of the present application) is basically a driver performing a driving operation, and is automatically performed only in a predetermined case. A vehicle travel control device capable of interposing a steering system, comprising: a main steering wheel connected to a steering handle; and a sub-steering wheel that is independently steered from the steering handle only by driving an actuator. At the time of intervention of the automatic steering system, the auxiliary steering wheel is prioritized and operated.

The invention according to claim 2 of the present application (hereinafter,
According to a second invention of the present application), in the first invention, the vehicle is provided with a dangerous state detecting means for detecting a predetermined dangerous state while the vehicle is traveling, and the automatic steering system is arranged so that the vehicle is driven by a driver. Only when the dangerous state is detected by the dangerous state detecting means, it is set to intervene in order to avoid the dangerous state.

The invention according to claim 3 of the present application (hereinafter,
The third invention of the present application) is, in the above-mentioned first invention, whether the vehicle has a traveling lane recognition means for recognizing a traveling lane of the own vehicle and an intention of the driver to travel along the traveling lane of the own vehicle. The automatic steering system includes a determination means for determining whether or not the driver determines that the driver intends to travel along the vehicle traveling lane by the determination means. It is characterized by being set to intervene in order to travel along.

Further, the invention according to claim 4 of the present application
(Hereinafter, referred to as a fourth invention of the present application) In the third invention, the vehicle is provided with a side edge distance detecting means for detecting a distance between a side edge of a vehicle traveling lane and the vehicle. The maximum steering amount of the auxiliary steering wheel is set smaller than the maximum steering amount of the main steering wheel, and when the detection value of the side edge distance detection means exceeds a predetermined value during the automatic steering system intervention, the auxiliary steering wheel is operated. Only the wheels are automatically steered, and when the detected value is equal to or less than the predetermined value, the main steered wheels are also automatically steered.

The invention according to claim 5 of the present application
(Hereinafter, referred to as a fifth invention of the present application) is characterized in that, in the first to fourth inventions, the main steering wheel is a left and right front wheel, and the sub steering wheel is a left and right rear wheel. It is a thing.

The invention according to claim 6 of the present application (hereinafter,
The sixth invention of the present application) is basically a vehicle drive control device in which a driver performs a driving operation so that the automatic steering system can intervene only in a predetermined case. Between the steered wheel to be steered, a connecting portion having a connection releasing means for releasing the connection between the steering wheel and the steered wheel is provided only when the driver does not operate the steering wheel during the automatic steering system intervention. It is something like.

Further, the invention according to claim 7 of the present application
(Hereinafter, referred to as a seventh invention), in the sixth invention, the steering shaft supporting the steering handle is divided into a front shaft and a rear shaft into two parts, and a front shaft. The rear end and the front end of the rear shaft are each formed in a hollow shape,
A piston member for connecting the front and rear shafts is provided in the hollow portion so as to be slidable forward and backward, and driving means for moving the piston member forward and backward at a predetermined timing is provided, and the driving means is the connection releasing means. It is characterized by configuring.

[0013]

According to the first aspect of the present invention, when the automatic steering system intervenes, the auxiliary steering wheel, which is steered only by the drive of the actuator independently of the steering wheel, is preferentially operated. During the intervention of the automatic steering system, it is possible to prevent the driver's operation of the steering wheel from interfering with the abrupt rotation operation of the steering wheel caused by the automatic steering and giving the driver a feeling of strangeness.

Further, according to the second invention of the present application, basically, the same effect as that of the first invention can be obtained. In particular, in a vehicle equipped with an automatic steering system set to intervene to avoid the dangerous state only when the dangerous state is detected by the dangerous state detecting means during traveling by the driver's driving, When the automatic steering system intervenes, it is possible to prevent the driver's operation of the steering wheel from interfering with the abrupt rotation of the steering wheel caused by the automatic steering and causing the driver to feel uncomfortable.

Further, according to the third invention of the present application, basically, the same effect as that of the first invention can be obtained. In particular, in a vehicle equipped with an automatic steering system configured to intervene to travel along the vehicle driving lane only when it is determined that the driver is willing to travel along the vehicle driving lane. During the intervention of the automatic steering system, it is possible to prevent the driver's operation of the steering wheel from interfering with the abrupt rotation operation of the steering wheel caused by the automatic steering and giving the driver a feeling of strangeness.

Further, according to the fourth invention of the present application,
Basically, the same effect as that of the third invention can be obtained. Moreover, since the maximum steering amount of the auxiliary steering wheel is set smaller than the maximum steering amount of the main steering wheel, by operating the auxiliary steering wheel, the vehicle travels along the vehicle traveling lane. In this case, it is possible to make a relatively small correction of the course of the host vehicle (so-called corrected steering).
When the detection value of the side edge distance detecting means exceeds a predetermined value, that is, while the risk of deviation from the vehicle traveling lane is relatively small, only the auxiliary steering wheel with a relatively small maximum steering amount is automatically steered. When the detected value is equal to or less than the predetermined value, that is, when the risk of departure from the vehicle traveling lane is relatively high, the main steering wheel for which the maximum steering amount is set larger is also automatically steered. Since this is done, it is possible to prevent departure from the driving lane more safely, smoothly, and reliably. In this case, the turning operation of the steering wheel due to the automatic steering intervention during the correction steering can be eliminated, and the driver can be prevented from feeling uncomfortable.

Further, according to the fifth invention of the present application,
Basically, the same effects as those of the first to fourth inventions can be obtained. Particularly, since the main steered wheels are the left and right front wheels and the sub-steered wheels are the left and right rear wheels, the front wheel side is connected to the steering handle while the rear wheel side is driven by the actuator independently of the steering handle. The four-wheel steering mechanism of the type configured as described above can be used.

Further, according to the sixth aspect of the present invention, since the connecting portion provided with the connection releasing means is provided between the steering handle and the steered wheels steered by the steering handle, when the automatic steering system is involved. Only when the driver does not operate the steering wheel, the connection between the steering wheel and the steered wheels is released, and as a result, the automatic steering system can be intervened without causing the driver to feel uncomfortable. On the other hand, when the driver operates the steering wheel, the steering wheel and the steered wheels are connected to each other, so that the steering operation of the driver is not restricted even during the intervention of the automatic steering system.

Further, according to the seventh invention of the present application,
Basically, the same effect as the sixth invention can be obtained. In particular, the steering shaft that supports the steering handle is divided into two parts in the front and rear, the rear end of the front shaft and the front end of the rear shaft are connected by the piston member, and the piston member is provided with a predetermined size. Since the driving means is provided as the connection releasing means for moving the steering wheel back and forth at the timing, by controlling the driving means, the steering wheel and the steered wheels are surely connected under normal conditions, while the driver is operated during the automatic steering system intervention. When there is no handle operation by, the connection between the two can be released.

[0020]

Embodiments of the present invention will now be described in detail with reference to the accompanying drawings. First, the first embodiment will be described. FIG. 1 is an explanatory view schematically showing a vehicle steering mechanism according to a first embodiment of the present invention. As shown in this figure,
The vehicle 10 is a so-called four-wheel vehicle configured to steer not only the front wheels W1 and W2 connected to the steering wheel 12 but also the left and right rear wheels W3 and W4.
A wheel steering (hereinafter, abbreviated as 4WS) mechanism is provided. That is, the front wheel steering rod 1 is provided between the left and right front wheels W1 and W2.
A front wheel steering mechanism 15 that steers the front wheels W1 and W2 by the left and right movement of the rear wheel 4 is provided, while the rear wheel W3 and W4 are moved between the left and right rear wheels W3 and W4 by the left and right movement of the rear wheel steering rod 16.
A rear wheel steering mechanism 17 for steering the steering wheel 4 is provided, and a steering handle 12 is connected to the front wheel steering mechanism 15 via a steering shaft 13. That is,
Although not specifically shown, a pinion fixed to the tip of the steering shaft 13 meshes with a rack provided on the front wheel steering rod 14.

Further, the rear wheel steering mechanism 17 is provided with a steering ratio variable mechanism 18 capable of varying the ratio of the steering amount of the rear wheels W3, W4 to the steering amount of the front wheels. The variable mechanism 18 is connected to a 4WS controller 19 which is mainly composed of, for example, a microcomputer so that signals can be exchanged. In this 4WS controller 19,
A vehicle speed sensor 7 for detecting the vehicle speed of the host vehicle 10 and a steering angle sensor 8 for detecting the steering angle (steering wheel steering angle) of the steering wheel 12 are electrically connected to each other.
The detected value of is input to the 4WS controller 19.
Then, when the steering wheel 12 is steered, the rear wheels W3, W are generated according to the steering angle and the vehicle speed, for example, when the steering wheel angle is low and the steering angle is relatively large.
4 is steered in the opposite phase to the front wheels W1 and W2 to improve the turning performance of the vehicle, or when the steering wheel steering angle is relatively high and the steering wheel angle is small, the rear wheels W3 and W4 are in phase with the front wheels W1 and W2. The steering ratio of the rear wheels is set so that the steering state of the four wheels is optimized, for example, by improving the turning performance when the vehicle is turned while the vehicle is traveling. In the case of the rear wheels W3, W4 side, it is not possible to steer too much, and the maximum steering amount is smaller than the maximum steering amount of the front wheels W1, W2 side by a certain amount or more so that the steering ratio is It is set.

In the present embodiment, the rear wheel steering mechanism 17 is
Not connected to the steering wheel 12,
It is operated independently of the operation of the steering handle 12. That is, although not specifically shown,
An actuator (a rear wheel actuator) for driving the mechanism 17 is connected to the rear wheel steering mechanism 17,
The rear wheel actuator is the 4WS controller 19 described above.
The drive is controlled by the rear wheel W3,
W4 is mechanically completely independent of the steering wheel 12 and is steered only by the rear wheel actuator. The rear wheel actuator constitutes a part of an automatic steering system described later and is used for automatic steering of the rear wheels W3 and W4. Although not specifically shown, more preferably, not only the steering shaft 13 but also an actuator for driving the front wheel steering mechanism 15 (front wheel actuator) is provided in the front wheel steering mechanism 15. The front wheel actuators are connected and are driven when the front wheels W1 and W2 are automatically steered. As the actuators for the front wheels and the rear wheels, it is possible to use various types well-known for automatic steering, such as an electric type such as a servo motor and a hydraulic type. it can.

The vehicle 10 is equipped with a travel control device having a so-called key plane system. With the key plane system, when operating in a running lane partitioned by white lines on the road, for example, careless steering operation that the driver is not aware of due to carelessness such as looking aside or dozing When the vehicle is about to deviate from the predetermined driving lane, such as when it is done, the vehicle is not prepared from the driving lane by intervening automatic steering or by issuing an alarm to alert the driver. In this embodiment, as will be described later, the automatic steering system intervenes to prevent deviation from the traveling lane. In addition, the vehicle 10 is automatically driven by its travel control mechanism by one switch operation.
The so-called auto cruise function for controlling the vehicle to maintain the current vehicle speed is provided, and the key plane system is set to operate only when the auto cruise function is operating.

Next, the traveling control device mounted on the automobile 10 will be described. FIG. 2 is a block configuration diagram showing a basic configuration of the traveling control device. As shown in this figure, the traveling control device 2 mounted on the automobile 10
Reference numeral 0 denotes, for example, an industrial video camera 1 (hereinafter, simply referred to as a camera), a signal processing unit 2 that processes a video signal from the camera 1, the signal processing unit 2, a vehicle speed sensor 7, and a steering angle sensor 8. An arithmetic unit 3 for performing a predetermined arithmetic operation based on each input signal of
A vehicle speed sensor 7, a steering angle sensor 8, a direction indicator 9 and a control unit 4 capable of driving and controlling a steering actuator unit 5 based on respective input signals from an auto cruise unit 6 described later. The switch of the auto cruise unit 6 is turned on by the driver.
When operated, it outputs an auto speed control signal to the control unit 4, and the control unit 4 receiving this output signal starts key plane control. Also,
The steering actuator unit 5 includes the front wheel actuator 5F and the rear wheel actuator 5 described above.
The actuators 5F and 5R are used for automatic steering in key plane control.
The 4WS controller 19 is incorporated in a part of the control unit 4, and the front wheel actuator 5
F constitutes a part of the 4WS mechanism as described above.

The camera 1 is, for example, as shown in FIG. 3, provided on the front end surface of the vehicle body of the vehicle 10, and is a side edge 22 of the traveling lane 21 of the vehicle 10 indicated by a white line (guide line) or a guard rail. Is to be imaged. Camera 1
The video signal output from is processed into a signal that can be processed by the arithmetic unit 3 by the signal processing unit 2, and then supplied to the arithmetic unit 3. This arithmetic unit 3 is
The side edge 22 of the vehicle traveling lane 21 is detected based on the input signal from the signal processing unit 2, and the vehicle 10 is detected based on the input signal from the vehicle speed sensor 7 and the input signal from the steering angle sensor 8. Is estimated, and an angle θ at which the line 13 representing the estimated traveling path of the vehicle 10 and the side edge 22 of the traveling lane 21 intersect and a distance L to the intersection P are calculated.

The arithmetic unit 3 also calculates the first and second threshold values L1 and L2 for the distance L based on the angle θ and the vehicle speed (L1 <L2). The control unit 4 compares the distance L with the first and second threshold values L1 and L2 to predict the departure state of the vehicle 10 from the traveling lane 21, and the distance L is shorter than the second threshold value L2. Then, (L1 <L <L2), the rear wheel actuator 5F automatically steers the rear wheels W3 and W4 to perform the correction steering described later.
At this time, a warning may be given to the driver by an alarm buzzer or the like. Then, when the distance L becomes shorter than the first threshold value L1 (L <L1), it is determined to be in a dangerous state, a key plane system operation routine described later is started, and the front wheel actuator 5R is driven and controlled. There is.

The above-mentioned correction steering is a steering for making a comparatively slight correction of the course of the vehicle 10 when traveling along the vehicle traveling lane 21, and the side edge 22 of the vehicle traveling lane 21 and the vehicle 10. As long as the distance is more than a certain amount and the risk of deviation from the traveling lane 21 is relatively small, the key plane traveling is performed by this correction steering. Further, since this correction steering requires a relatively small amount of steering and comparatively fine steering is required, the rear wheels W3, W4 set to have a small maximum steering amount.
Is performed using. And the side edge 2 of the traveling lane 21
When the distance between the vehicle 2 and the host vehicle 10 becomes short and the risk of deviation increases, the front wheel W for which the maximum steering amount is set to a large value
The 1st and 2nd sides are also automatically steered.

The operation of the key plane system having the above configuration will be described with reference to the flow charts of FIGS. In this embodiment, as described above, the key plane system is set to operate only when the auto cruise function is working.
Further, in the following description, it is assumed that the above-mentioned correction steering also constitutes a part of the key plane system. The flowchart of FIG. 4 shows an outline of the key plane system. First, in step # 1, it is determined whether the auto cruise switch is turned on and the auto cruise function is working. If the result of this determination is YES, is the steering amount of the steering wheel 12 below a certain value (step # 2),
It is sequentially determined whether the steering angular velocity of No. 2 is a certain value or less (step # 3). Then, if the determination results in each of these steps # 2 and # 3 are both YES, it is determined in step # 4 whether or not the white line indicating the side edge 22 of the traveling lane 21 is recognizable, and this determination result is If YES, the white line information is taken in to recognize the side edge 22 of the own vehicle traveling lane 21, and the actuators 5F and 5R are appropriately driven in step # 6 so as to prevent deviation from the traveling lane 21. It is supposed to be done. Incidentally, the above step # 1
The key plane system does not operate if there is at least one NO in the determination results of each step up to step # 4.

FIG. 5 shows a basic flow chart of the key plane system. First, the key plane system intervention start determination routine is executed (step # 11), and then it is determined whether or not the key plane system intervention start condition is satisfied (step # 12). Then, until this condition is satisfied (step # 12: NO), the process returns to step # 11, and when the above condition is satisfied (step # 12: YE
S), the key plane system operation routine is executed (step # 13). Next, the key plane system intervention end determination routine is executed (step # 14), and it is determined whether or not the key plane system intervention end condition is satisfied (step # 15) until the condition is satisfied. (Step # 15: NO), the key plane system operation routine is continued. Then, when the key plane system intervention end condition is satisfied (step # 15: YES), the process returns to step # 11.

6 and 7 show step # 11 in FIG.
5 is a flowchart showing the contents of a key plane system intervention start determination routine in FIG. First, driving lane 2
1 side edge information (input signal from the signal processing unit 2) is input (step # 21), then the vehicle speed V and the steering angle φ are read, and the turn signal is input (step # 21).
22). Next, whether the steering angle φ is larger than a predetermined value φ1,
Further, it is determined whether or not the steering speed φ'is greater than a predetermined value φ'2 (step # 23), and it is determined whether a turn signal is input (step # 24). It is determined whether or not the switch is turned on (step # 25). When at least one of the determinations in step # 23 and step # 24 is YES,
Assuming that the driver intends to deviate from the current driving lane, the process proceeds to step # 39 in FIG.
It is judged that the key plane system intervention start condition is not satisfied,
This determination routine ends. Also, the above step # 2
If the determination result in 5 is NO, it is determined that there is no intention to run the key plane, and similarly, step # 39 in FIG.
Then, it is determined that the key plane system intervention start condition is not satisfied, and this determination routine is ended.

On the other hand, when it is determined that the driver has the intention of traveling on the key plane and the driver is not consciously steering (NO in steps # 23 and # 24, and step # 25). Is YES), the traveling direction of the vehicle 10 is estimated from the vehicle speed V and the steering angle φ (step # 26), and the line 2 representing the estimated traveling path of the vehicle 10 is estimated.
3 and the side edge 22 of the traveling lane 21 are obtained, and the angle θ between the line 23 and the side edge 22 at the intersection P is obtained, and the distance L from the vehicle 10 to the intersection P is calculated. (Step # 27). In this embodiment, a threshold value L1 for the distance L is set here, and when L <L1, it is determined that there is a risk that the vehicle may depart from the traveling lane 21. That is, it is determined that the key plane system intervention start condition is satisfied (step # 12: YE in FIG. 5).
S), the key plane system operation routine is executed (step # 13 in FIG. 5), but this key plane system is merely an assisting means for the driver,
The threshold value L1 is set based on the policy that the intervention of the key plane system should be minimized and the viewpoint that the excessive lateral G is prevented from occurring during the intervention of the key plane system.

That is, the threshold L1 is set as a function of the vehicle speed V, and the lower the vehicle speed V, the shorter the threshold L1 is set. Further, when the angle θ is equal to or greater than the predetermined value θ1, it is determined that the vehicle 10 is away from the target side edge 22, and in that case, the steering amount at the time of intervention of the key plane system is small, and therefore the lateral direction is small. It is determined that G is also small, and the larger the angle θ is, the shorter the threshold value L1 is set.
Therefore, it is determined whether or not the angle θ is smaller than the predetermined value θ1 (step # 28), and if θ <θ1 (step # 28: YES), L1 = α1 · V + β1 is set (step # 28).
29), if θ ≧ θ1 (step # 28: NO) L1 =
It is set as α2 · V / θ + β2 (step # 30).
Note that α1, α2, β1, and β2 are constants.

Next, in step # 31, the distance L is compared with L2 which is a function of the set value L1 (L2> L1), and L ≧ L2.
While it is (step # 31: NO), it is determined that the key plane system intervention start condition is not satisfied (step # 39).
Next, when L <L2 (step # 31: YES), it is determined in step # 36 whether or not L <L1 is satisfied, and while L2> L ≧ L1 (step # 36: N
O), it is determined that the correction steering intervention start condition for performing only the correction steering of the key plane system is satisfied. That is, during this period, only the rear wheel actuator 5R is driven and the automatic steering is performed only for the rear wheels W3 and W4. At this time, the rear wheels W3 and W4 are steered only by the rear wheel actuator 5R independently of the steering handle 12. Therefore, during the automatic steering system intervention for performing this correction steering, the driver's steering wheel operation and automatic steering are performed. There is no possibility that the driver will feel uncomfortable due to the interference with the turning operation of the handle 12 due to. When L <L1 is satisfied (step # 36: YES), it is determined that the intervention start condition of the entire key plane system for automatically steering not only the rear wheels W3 and W4 but also the front wheels W1 and W2 is satisfied (step # 36). #
37) and terminates this determination routine.

In the present embodiment, more preferably, even if the distance L is larger than the threshold value L2, if the manual correction steering by the driver is frequently repeated to a certain extent or more, The threshold L2 is set to be large so that the correction steering in this manual can be made as small as possible and the portion can be automatically controlled. That is, when L ≧ L2 (step # 3
1: NO), the steering wheel steering angle φ is a predetermined value φ3 (φ3 << φ
It is determined whether or not it is larger than 1), that is, whether there is a correction steering by the driver (step # 32), and this is YE.
If S, count the frequency K (step #
33). Then, when the frequency K exceeds the predetermined value K1 (step # 34: YES), correction is made by adding ΔL to the threshold value L2 (step # 35). As a result, the range in which the correction steering by the automatic steering can be performed is widened, the manual correction steering of the driver can be reduced, and the burden on the driver can be reduced.

Next, including the case where the traveling lane 21 draws a curve as shown in FIG. 8, for example, the vehicle 1 used in step # 26 in the flowchart of FIG.
A method of estimating the traveling direction of 0 will be described. This traveling direction estimation routine is performed based on the vehicle speed V and the steering angle φ.
It predicts the traveling path 23 of 0, and is specifically performed by calculating the curvature radius R1 of the traveling path 23 by the following formula. R1 = (1 + AV ² ) Lb · N / φ ...... However, A: Stability factor N: Steering gear ratio Lb: Wheel base Further, a yaw rate sensor that detects the yaw rate generated by the host vehicle 10 is used. Based on the detected yaw rate ψ and the vehicle speed V, the host vehicle 1
You may predict the traveling path of 0. Estimated route 1 in that case
The radius of curvature R2 of 3 is calculated by the following formula. R2 = V / ψ ...

By the way, when there is a cant on a curved portion such as an expressway, the steering angle φ does not match the actual turning angle of the vehicle 10, and the traveling path of the vehicle 10 predicted based on this steering angle φ. The radius of curvature 13 is larger than the radius of curvature of the actual traveling path. Further, even when the vehicle 10 is traveling straight ahead, the steering wheel is usually delicately steered to the left or right. Therefore, when the traveling path of the vehicle 10 is predicted by following the steering angle φ, it is predicted. The traveled path 13 that has been set does not match the actual traveled path. Therefore, when the steering angle φ is smaller than a predetermined value, the curvature radius R2 calculated from the formula is selected, and when the steering angle φ is equal to or larger than the predetermined value, among the curvature radii R1 and R2 calculated from the formula, respectively. It is preferable to select the smaller one.

That is, when the vehicle 10 turns on a curved road having a cant, the vehicle 10 makes a turning motion by the cant even if the steering wheel is not steered greatly, so that the yaw rate generated in the vehicle 10 is generated. ψ
By determining the radius of curvature R2 based on
The traveling path 13 of 0 is accurately predicted. Also,
When the host vehicle 10 makes a sharp turn, a radius of curvature R1 corresponding to a large steering angle φ is selected. On the other hand, when the host vehicle 10 travels straight on a straight road, the steering wheel is slightly operated, but the yaw rate φ does not occur. Therefore, based on this yaw rate φ, the radius of curvature R2 predicted to be a straight road is Will be selected. Further, in addition to the above-mentioned determination means, the own vehicle 10
Means for detecting the distance d from the vehicle to the side edge 12 of the traveling lane 11 is provided, and the distance d detected by this detecting means
The above determination may be performed in consideration of the above. By doing so, the relative positional relationship between the host vehicle 10 and the side edge 12 of the traveling lane 11 at the present time is also taken into consideration, so that the determination accuracy is improved.

Next, FIG. 10 is a diagram for explaining the key plane system operation routine after the start of the key plane system intervention in the vehicle travel control device according to the present invention. In this key plane system, depending on the distance d from the current position of the vehicle 10 to the side edge 22 of the traveling lane 21, the target position D (the distance to the side edge 22) for the forward point P5 in the traveling direction of the vehicle 10. ) Is set. This target position D is defined by two virtual lines 25 parallel to the side edge 22,
The virtual line 25 is set in a region between 26, and one virtual line 25 is close to the side edge 22 so that a predetermined distance D1 with the side edge 22 is relatively short, and the other virtual line 26 is the side edge 22. Driving lane 2 so that the distance between
It is set on the center side of 1. Then, the deviation a from the target position D of the front point P5 is calculated, the steering angle φ is determined according to the deviation a, and the automatic steering is performed.

FIG. 11 shows a basic flow chart of the key plane system operation routine in step # 13 of FIG. First, in the same manner as described above, the information on the side edge 22 is input (step # 41), and then the target position D is set to the vehicle 10
Is calculated from the map shown in FIG. 12 as a function of the distance d from the current position to the side edge 22 (step # 42). As is clear from this map, when the distance d is small, the target position D is set to D = D1, and when the distance d is large, the target position D is set to D = D2. . That is, the correction steering amount at the time of automatic steering is made as small as possible so that a large lateral G is not applied to the occupant. Next, the deviation a of the front point P5 from the target position D is calculated (step # 4
3) The steering angle φ is determined from the map shown in FIG. 13 according to the deviation a (step # 44), and steering control by automatic steering is performed (step # 45).

Normally, the correction steering by the automatic steering is first started, but more preferably, step # 46.
Then, whether or not the driver manually corrects this automatic correction steering, that is, the steering angle φ>
It is detected whether or not there is a case where the predetermined value φ3 (φ3 << φ1) occurs. Then, the frequency K of the manual correction of the driver within a predetermined time is counted up (step # 47), and if the frequency K within the predetermined time exceeds the predetermined value K2, the correction steering by the automatic steering is unsuccessful. A correction of the threshold L2 is made as being too much necessary,
The distance at which the correction steering by the automatic steering is started is set shorter by ΔL '(step # 49).
The count value of the frequency K is cleared when the predetermined time for counting up has elapsed.

FIG. 14 shows a flow chart of a key plane system operation routine in consideration of the case where the driving lane 21 draws a curve. First, the information on the side edge 22 is input (step # 51), and then the curvature radius R of the traveling lane 21 is calculated from the information on the side edge 22 (step # 5).
2). The map for obtaining the target position D from the distance d in this case uses the radius of curvature R as a parameter, as shown in FIG. 15, and even when the distance d is small, if the radius of curvature R is small, the target position D is set to the traveling lane 11. It is set so that it approaches the center of the. That is, the target position D is set to the own vehicle 10
Distance from the current position of the side edge 22 to the side edge 22 and radius of curvature R
Is calculated from the map of FIG. 15 (step # 53). Next, as in steps # 43 to # 45 of FIG. 11, the target position D of the front point P5 is set.
Is calculated (step # 54), the steering angle φ is determined from the map shown in FIG. 16 according to the deviation a (step # 55), and steering control by automatic steering is performed (step # 54).
56). Note that in this case as well, step # in FIG.
Similarly to 46 to step # 49, the threshold value L2 that determines the distance at which the correction steering by the automatic steering is started may be corrected according to the manual correction frequency K of the driver.

FIG. 10 is a diagram for explaining a key plane system intervention end determination routine in the vehicle drive control device according to the present invention. In this key plane system intervention end determination routine, the deviation (future deviation) b1 from the virtual line 27 parallel to the side edge 22 passing through the target position D predicted at the front point P5 of the vehicle 10 and the current deviation b2 Is compared with a predetermined distance b, and when both the future deviation b1 and the current deviation b2 are smaller than the predetermined distance b, the vehicle 1 after the key plane system intervention is completed.
It is determined that the possibility of re-departure from the 0 lane 21 is low.

FIG. 17 is a flow chart showing the contents of the key plane system intervention end judgment routine in step # 14 of FIG. 5 when the traveling lane 21 is a straight line. First, enter the side edge information (step # 6
1) Next, the future deviation b1 and the current deviation b2 are calculated (step # 62 and step # 63). And future deviation b
1 and the current deviation b2 are respectively compared with the predetermined distance b (step # 64 and step # 65), and when the future deviation b1 and the current deviation b2 are both smaller than the predetermined distance b.
(Step # 64: YES, Step # 65: YES) It is determined that the key plane system intervention end condition is satisfied (Step # 66), and when at least one of the future deviation b1 and the current deviation b2 is equal to or greater than the predetermined distance b (Step # 64
Alternatively, step # 65: NO), it is determined that the key plane system intervention has not been completed (step # 67), and the key plane system intervention is continued. Also, the future deviation b1 above
When performing the key plane system intervention end determination using the current deviation b2 and the current deviation b2, it is sufficient to perform the end determination when both deviations b1 and b2 are smaller than the predetermined distance b for a fixed time (for example, 2 seconds). It can be determined that the yaw motion has subsided, and more stable release determination can be performed. By making such a determination, the frequency of key plane system intervention can be reduced.

FIG. 18 is a flow chart showing the contents of the key plane system intervention end judgment routine in consideration of the case where the driving lane 21 is a curve. First, the side edge information is input (step # 71), and the curvature radius R of the traveling lane 21 is calculated from this side edge information (step # 7).
2). Next, this radius of curvature R is compared with a predetermined value R ₀ (step # 73), and when R <R ₀ (step # 73: YE
S), it is determined that the key plane system intervention end condition is not satisfied (step # 79), and the key plane system intervention is continued. On the other hand, when R ≧ R ₀ (step # 73: N
O), the same processes as in steps # 62 to # 67 of FIG. 17 are performed in steps # 74 to # 79. In the present embodiment, when the radius of curvature R of the traveling lane 11 is smaller than the predetermined value R ₀ , the possibility of re-intervention of the key plane system is reduced by not determining the key plane system intervention end.

Finally, like FIG. 18, FIG. 19 is a flowchart showing the contents of the key plane system intervention end determination routine in consideration of the case where the driving lane 21 is a curve. In this case, enter the edge information (step #
81) and after calculating the radius of curvature R of the traveling lane 21 from this side edge information (step # 82), the predetermined value b is obtained as a function of the radius of curvature R from the map shown in the figure (step # 83). . Subsequent steps # 84 to # 8
Step 9 is the same as step # 74 to step # 79 in FIG.

As described above, according to this embodiment, during the intervention of the key plane system, that is, during the intervention of the automatic steering, the steering wheel 12 is operated independently by driving the actuator 5R (actuator for the rear wheels). Since the rear wheels W3 and W4 (sub-steering wheels in the present application) are preferentially operated, during this automatic steering intervention, the driver's steering wheel operation and the steering wheel turning operation by the automatic steering interfere and the driver feels uncomfortable. Can be prevented.

Particularly, since the maximum steering amounts of the rear wheels W3 and W4 are set to be smaller than the maximum steering amounts of the front wheels W1 and W2 (main steering wheels in the present application) by a certain amount or more, the rear wheels W3 and W4 are operated. As a result, it is possible to perform the correction steering during the key plane. Then, the own vehicle 10 is in the driving lane 2
When the risk of deviation from 1 is relatively small, the rear wheels W3 and W4 having a small steering amount are automatically steered and correction steering is performed, and the risk of deviation from the traveling lane 21 becomes relatively high. Since the front wheels W1 and W2 for which the maximum steering amount is set to a larger value are automatically steered, the departure from the traveling lane 21 can be prevented more safely and smoothly. In this case, the turning operation of the steering wheel 12 due to the automatic steering intervention during the correction steering can be eliminated, so that it is possible to prevent the driver from feeling uncomfortable.

Next, a second embodiment of the present invention will be described. 20 is a side view of the steering handle 32 according to the second embodiment and the steering shaft 33 that supports the steering handle 32 at the rear end.
As shown in this figure, the steering shaft 33
In the middle thereof, the front shaft 35 and the rear shaft 3
It is formed by dividing the front and rear into four. As shown in detail in FIG. 21 and FIG. 22, the front end portion of the rear shaft 34 and the rear end portion of the front shaft 35, that is, the mutual connecting portion 33A are formed in a substantially cylindrical hollow shape. A piston member 36 that is axially slidable in a part
Is provided. Front and rear splines 36c and 36b extending in the axial direction are formed on the piston member 36,
The rear side (right side in FIGS. 21 and 22) spline 36b meshes with the spline 34b formed on the rear shaft 34, and the front side (left side in FIGS. 21 and 22) spline 36c forms the spline formed on the front shaft 35. Three
It is designed to mesh with 5c. A hydraulic chamber 37 is formed between the front portion of the piston member 36 and the inner wall portion of the front shaft 35, and an oil passage 38 is introduced into the hydraulic chamber 37. Further, in front of the front end surface of the piston member 36, a spring 39 for urging the piston member 36 to the rear side is arranged.

With the above construction, when the hydraulic pressure is not applied to the hydraulic chamber 37, the piston member 36 is moved backward (FIG. 21, by the urging force of the spring 39) as shown in FIG.
22 is pressed to the right), and in this state, the rear spline joint portion B (the joint portion between the spline 36b and the spline 34b) and the front spline joint portion C are pressed.
(The connecting portion between the spline 36c and the spline 34c) maintains the connecting relation. Then, when a hydraulic pressure of a predetermined pressure is introduced from the oil passage 38, as shown in FIG. 22, the piston member 3 is overcome by overcoming the urging force of the spring 39.
6 is slid forward by a predetermined amount (left in FIGS. 21 and 22). By this movement, in the rear side spline joint portion B, the joint relationship between the spline 36b and the spline 34b is released. That is, the connection between the rear shaft 34 and the front shaft 35 is released,
The connection between the steering wheel 32 and the steered wheels is released. Thus, the piston member 3
6, the rear side spline coupling portion B and the spring 39 constitute a connecting means for connecting the rear shaft 34 and the front shaft 35, that is, a connecting means for the steering handle 32 and the steered wheels. Oil passage 3
8) constitutes the connection releasing means.

Next, the timing control for releasing and connecting the connecting means between the rear shaft 34 and the front shaft 35 will be described. FIG. 23 shows a basic flow chart of the key plane system operation routine of this embodiment, and except that there is a step of releasing the connecting means, steps # 41 to # 11 of FIG. 11 in the first embodiment. The same processing as # 45 is performed. That is, first input the information of the side edge 22 (step # 101), and then
The target position D is calculated from the map shown in FIG. 12 as a function of the distance d from the current position of the vehicle 10 to the side edge 22.
(Step # 102). Next, the deviation a of the front point P5 from the target position D is calculated (step # 103), and the steering angle φ is determined from the map shown in FIG. 13 according to this deviation a (step # 104). Then, step # 105
Then, the oil is introduced into the hydraulic chamber 37 to release the connecting means (that is, the connection between the rear shaft 34 and the front shaft 35 is released), and then the steering control by automatic steering is performed (step # 106). In this case, when it is determined from the input data from the steering angle sensor that the driver has operated the steering wheel, the connecting means is engaged and the steered wheels (not shown) can be steered by the steering wheel 32. There is.

As described above, the connection between the steering wheel 32 and the steered wheels (not shown) is released only when the driver does not operate the steering wheel during the intervention of the automatic steering system, and the driver feels uncomfortable. The automatic steering system can be intervened without the need. On the other hand, when the driver operates the steering wheel, the steering wheel 32 and the operation wheel (not shown) are connected to each other, so that the driver's steering operation is not restricted even during the intervention of the automatic steering system. .

FIG. 24 is a flow chart showing the contents of the key plane system intervention end judgment routine in this embodiment. First, the vehicle speed V and the steering angle φ are read, and a turn signal is input (step # 11).
1). Next, it is determined whether or not the steering angle φ is larger than a predetermined value φ1 and whether or not the steering speed φ ′ is larger than a predetermined value φ′2 (step # 112), and the direction indicator signal is input. It is determined whether or not (step # 113),
It is determined whether the vehicle speed V is lower than a predetermined value V1.
(Step # 114). Incidentally, in the present embodiment, whether or not the auto cruise switch is turned on is not particularly a requirement for key plane system intervention. If at least one of the determinations in steps # 112 to # 114 is YES, it is assumed that the driver intends to deviate from the current driving lane, the process proceeds to step # 120, and the key plane system intervention end condition is set. It is determined that the connection is established, and the connecting means is connected as described later.
(Step # 121), this determination routine ends.

If it is determined that the driver has the intention of traveling on the key plane and that the driver is not intentionally steering the steering wheel (NO in step # 112 to step # 114), the step is executed. Input the side edge information in # 115, then the future deviation b1 and the current deviation b2
Is calculated (step # 116 and step # 117).
Then, the future deviation b1 and the current deviation b2 are respectively compared with the predetermined distance b (step # 118 and step # 11).
9), future deviation b1 and present deviation b2 are both predetermined distance b
If it is smaller than (step # 118: YES, step # 119: YES), it is determined that the key plane system intervention end condition is satisfied (step # 120), and step # 121
Then, the oil is discharged from the hydraulic chamber 37 and the connecting means is fastened (that is, the rear shaft 34 and the front shaft 35 are coupled). On the other hand, when at least one of the future deviation b1 and the current deviation b2 is the predetermined distance b or more (step # 118 or step # 119: NO),
It is determined that the key plane system intervention is not completed (step # 122), and the key plane system intervention is continued. In this case, the rear shaft 34 and the front shaft 3
Regarding the connection with 5, the released state is maintained.

Although the above-mentioned embodiments are all about the automatic steering system applied to the key plane system, the present invention is not limited to such a case, for example, an obstacle or another object. Effective against other drive control devices, such as a collision avoidance system for avoiding collisions with moving objects, which basically allows the driver to perform a driving operation so that the automatic steering system intervenes only when a predetermined time is reached. Can be applied to.

[Brief description of drawings]

FIG. 1 is an explanatory view schematically showing a steering mechanism of an automobile according to a first embodiment of the present invention.

FIG. 2 is a block configuration diagram of a traveling control device according to the first embodiment.

FIG. 3 is a diagram for explaining the content of a key plane system intervention start determination method in the traveling control device according to the first embodiment.

FIG. 4 is a flowchart showing an outline of a key plane system and an automatic steering system in the travel control device according to the first embodiment.

FIG. 5 is a basic flowchart of the key plane system.

FIG. 6 is a part of a flowchart illustrating an intervention start determination routine of the key plane system.

FIG. 7 is a part of a flowchart illustrating an intervention start determination routine of the key plane system.

FIG. 8 is a diagram for explaining the content of the intervention start determination method of the key plane system.

FIG. 9 is a diagram for explaining the content of an operation routine of the key plane system.

FIG. 10 is a diagram for explaining the contents of the intervention end determination method of the key plane system.

FIG. 11 is a flowchart illustrating an example of an operation routine of the key plane system.

FIG. 12 is a map used to calculate a target position in the operation routine of the key plane system.

FIG. 13 is a map used to calculate a steering angle in the operation routine of the key plane system.

FIG. 14 is a flowchart illustrating another example of the operation routine of the key plane system.

FIG. 15 is a map used to calculate a target position in another example of the operation routine of the key plane system.

FIG. 16 is a map used to calculate a steering angle in another example of the operation routine of the key plane system.

FIG. 17 is a flowchart illustrating an example of an intervention end determination routine of the key plane system.

FIG. 18 is a flowchart illustrating another example of the intervention end determination routine of the key plane system.

FIG. 19 is a flowchart illustrating still another example of the intervention end determination routine of the key plane system.

FIG. 20 is a side view illustrating a steering shaft and a steering handle according to a second embodiment of the present invention.

FIG. 21 is an enlarged vertical cross-sectional explanatory view showing a connected state of the connecting portion of the steering shaft.

FIG. 22 is an enlarged vertical cross-sectional explanatory view showing a connection release state of the connection portion of the steering shaft.

FIG. 23 is a flowchart illustrating an example of an operation routine of a key plane system in the travel control device according to the second embodiment.

FIG. 24 is a flowchart illustrating an example of an intervention end determination routine of the key plane system according to the second embodiment.

[Explanation of symbols]

 4 ... Control unit 5F ... Front wheel actuator 5R ... Rear wheel actuator 6 ... Auto cruise unit 10 ... Automobile 12,32 ... Steering handle 20 ... Travel control device 21 ... Own vehicle running lane 22 ... Side edge of running lane 36 ... Piston Member 37 ... Hydraulic chamber 38 ... Oil passage 39 ... Spring

Front page continuation (72) Inventor Kensuke Hayabuchi 3-1, Shinchi, Fuchu-cho, Aki-gun, Hiroshima Mazda Motor Corporation

Claims (7)

[Claims] 1. A driver basically performs a driving operation,
In a vehicle travel control device that allows an automatic steering system to intervene only in a predetermined case, a main steering wheel connected to a steering wheel and an auxiliary steering wheel that is steered only by driving an actuator independently of the steering wheel. A travel control device for a vehicle, comprising: a wheel, wherein the auxiliary steering wheel is prioritized to operate when the automatic steering system intervenes. 2. The vehicle is provided with a dangerous state detecting means for detecting a predetermined dangerous state during traveling, and the automatic steering system is arranged such that the dangerous state is detected by the dangerous state detecting means during traveling by a driver. The vehicle travel control device according to claim 1, wherein the vehicle travel control device is set to intervene to avoid the dangerous state only when the vehicle is detected. 3. The vehicle comprises a traveling lane recognition means for recognizing a traveling lane of the own vehicle, and a determination means for determining whether or not the driver intends to travel along the traveling lane of the own vehicle. The automatic steering system is set to intervene in order to travel along the vehicle traveling lane only when the determination means determines that the driver intends to travel along the vehicle traveling lane. The travel control device for a vehicle according to claim 1, wherein 4. The vehicle is provided with a side edge distance detecting means for detecting a distance between a side edge of a vehicle traveling lane and the vehicle, and a maximum steering amount of the auxiliary steering wheel is a maximum steering amount of the main steering wheel. If the detection value of the side edge distance detection means exceeds the predetermined value during the intervention of the automatic steering system, only the auxiliary steering wheel is automatically steered, and the detection value is less than or equal to the predetermined value. In the above case, the main steering wheel is also automatically steered, and the traveling control device for the vehicle according to claim 3. 5. The main steering wheel is a left and right front wheel, and the sub steering wheel is a left and right rear wheel.
The travel control device for a vehicle according to claim 4. 6. A driver basically performs a driving operation,
In a travel control device for a vehicle that allows an automatic steering system to intervene only in a predetermined case, between the steering wheel and a steered wheel steered by the steering wheel, the driver does not operate the steering wheel when the automatic steering system intervenes. A traveling control device for a vehicle, comprising a connecting portion provided with a connection releasing means for releasing the connection between the steering handle and the steered wheels only when there is no such connection. 7. A steering shaft for supporting the steering wheel is divided into a front shaft and a rear shaft into two parts, and a rear end part of the front shaft and a front end part of the rear shaft are hollow. A piston member that connects the front and rear shafts to the hollow portion is slidably arranged in the front and rear, and a driving unit that moves the piston member back and forth at a predetermined timing is provided. 7. The vehicle travel control device according to claim 6, wherein the connection release means is configured.