JP4411794B2 - Vehicle travel control device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a vehicle travel control device including an inter-vehicle distance control means for deriving an inter-vehicle distance from a preceding vehicle and maintaining the inter-vehicle distance from the preceding vehicle in a predetermined state.
[0002]
[Prior art]
Conventionally, a travel control device has been developed that includes a detection means for detecting a distance between the preceding vehicle and the vehicle, and a vehicle distance control means that automatically controls the vehicle speed so as to maintain the distance between vehicles in a predetermined state. Yes.
[0003]
[Problems to be solved by the invention]
In the conventional traveling control device, the traveling state of the host vehicle is reflected in the traveling state of the preceding vehicle. Therefore, when the preceding vehicle is traveling so as to frequently repeat acceleration and deceleration, the behavior of the preceding vehicle is followed as it is. There is a risk that the ride comfort will deteriorate due to repeated repeated acceleration and deceleration.
[0004]
The present invention has been made in view of the above situation, and provides a travel control device for a vehicle provided with an inter-vehicle distance control means capable of performing smooth inter-vehicle distance control without reflecting an undesirable behavior of a preceding vehicle. The purpose is to provide.
[0005]
[Means for Solving the Problems]
In order to achieve the above object, in the present invention, the detection means detects the inter-vehicle distance from the preceding preceding vehicle, the virtual preceding vehicle setting means sets the virtual preceding vehicle having the same vehicle speed as the preceding preceding vehicle, and the target acceleration candidate for the preceding vehicle By setting the smaller of the target acceleration candidates for the virtual preceding vehicle as the target acceleration and controlling the vehicle speed of the own vehicle, the inter-vehicle distance control for the virtual preceding vehicle is performed even when the preceding vehicle is in an undesirable behavior The vehicle speed is controlled smoothly.
[0006]
In this case, it is preferable that the virtual leading vehicle is set at a rear position in a state where the predetermined inter-vehicle distance control is performed on the preceding preceding vehicle. Moreover, it is preferable to use radar means (for example, radio wave radar) as the detection means. By using radio wave radar, the detection means is provided at a position where the preceding preceding vehicle cannot be seen when radio waves pass under the floor of the preceding vehicle. In addition, it is possible to detect the distance between the preceding vehicle and the preceding vehicle.
[0007]
When the detection means can be provided at a position where the preceding vehicle can be seen, it is possible to apply a photographing means such as a laser means or a camera as the detection means. The inter-vehicle distance control means detects the inter-vehicle distance from the preceding vehicle by the detecting means, and controls the engine and transmission based on the inter-vehicle distance information (the inter-vehicle distance / relative speed), the vehicle state, and the driving operation state. A means for controlling the vehicle speed or the like is applied.
[0008]
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 shows a schematic configuration of a vehicle provided with a travel control apparatus according to an embodiment of the present invention, FIG. 2 shows a concept for explaining virtual preceding vehicle setting, and FIG. 3 shows a flowchart of inter-vehicle distance control. .
[0009]
As shown in FIG. 1, a vehicle 1 that is the host vehicle is provided with a radar unit 2 (for example, a laser radar or a radio wave radar) that can detect a preceding vehicle and a preceding preceding vehicle that travels ahead of the preceding vehicle. The vehicle 1 is provided with a handle angle sensor 8. The detection information of the radar means 2 and the detection information of the handle angle sensor 8 are input to the controller 3. Information from the vehicle speed sensor 4 is input to the controller 3.
[0010]
In the controller 3, by operating a switch 7 provided on a lever or the like, the preceding vehicle and the preceding preceding vehicle existing in the course of the host vehicle 1 are recognized from the surrounding road environment, and the preceding vehicle and the preceding preceding vehicle are recognized. Is recognized (detection means). Then, the controller 3 controls the throttle opening so as to keep the following time (corresponding to the following distance corresponding to the vehicle speed) in a predetermined state based on the distance from the preceding vehicle (corresponding to the vehicle speed). The output of the engine 5 is controlled, the shift on the engine 5 side is controlled, and the operation of the brake actuator 6 is controlled to control the vehicle speed.
[0011]
In addition, the controller 3 sets a virtual leading vehicle behind the preceding preceding vehicle (virtual leading vehicle setting means), and based on the inter-vehicle distance from the virtual leading vehicle, the inter-vehicle time with the virtual leading vehicle (the inter-vehicle distance corresponding to the vehicle speed) The engine 5 output is controlled by controlling the throttle opening or the like, and the shift on the engine 5 side is controlled, and the operation of the brake actuator 6 is controlled to maintain the vehicle speed. To control.
[0012]
The controller 3 also calculates a target acceleration candidate for following the preceding vehicle (preceding vehicle target acceleration candidate calculating means) and a function for calculating a target acceleration candidate for following the virtual preceding vehicle (virtual leading vehicle). Target acceleration candidate calculation means), and selects a smaller one of the preceding vehicle target acceleration candidate calculated by the preceding vehicle target acceleration candidate calculation means and the virtual preceding vehicle target acceleration candidate calculated by the virtual preceding vehicle target acceleration candidate calculation means. A function for setting a target acceleration (target acceleration setting means) is provided. Then, the vehicle speed of the vehicle 1 is controlled based on the target acceleration set by the target acceleration setting means (control means).
[0013]
For this reason, even when the preceding vehicle has an unfavorable behavior such as frequent acceleration / deceleration, the inter-vehicle distance control for the virtual preceding vehicle can be performed to smoothly control the vehicle speed, thereby eliminating the deterioration of riding comfort. be able to.
[0014]
The setting of the virtual leading vehicle will be described based on FIG. FIG. 2 shows the case where the preceding vehicle approaches the preceding preceding vehicle and the virtual leading vehicle is positioned behind the preceding vehicle, for example, but the position of the virtual leading vehicle depends on the behavior of the preceding vehicle. Thus, it changes to an arbitrary position with respect to the preceding vehicle.
[0015]
When the vehicle 1 at the vehicle speed VS is controlling the inter-vehicle distance at the inter-vehicle time ht, the virtual preceding vehicle 22 having the same vehicle speed as the preceding preceding vehicle 21 is set behind the preceding preceding vehicle 21 (the vehicle speed VP2 of the preceding preceding vehicle 21). = Vehicle speed VP0 of the virtual preceding vehicle 22). The inter-vehicle distance between the preceding preceding vehicle 21 and the virtual preceding vehicle 22 is set to an inter-vehicle distance (ht × VP0: predetermined inter-vehicle distance) controlled by the inter-vehicle time ht when the virtual preceding vehicle 22 is at the vehicle speed VP0. When the preceding vehicle 23 is extremely close to the preceding preceding vehicle 21 at the vehicle speed VP1, the virtual leading vehicle 22 is positioned behind the preceding vehicle 23.
[0016]
The setting of the virtual leading vehicle 22 is not limited to the position where the predetermined inter-vehicle distance (ht × VP0) from the preceding preceding vehicle 21 is set, but is set to a certain distance behind the preceding preceding vehicle 21 regardless of the vehicle speed. Alternatively, the vehicle speed can be divided into a plurality of stages and set to a constant stepwise distance corresponding to each vehicle speed.
[0017]
The situation of inter-vehicle distance control will be described based on FIG.
[0018]
It is determined whether or not the preceding vehicle 23 is detected in step S1, and if it is determined that the preceding vehicle 23 is detected, it is determined whether or not the preceding vehicle 21 is detected in step S2. If it is determined in step S2 that the preceding preceding vehicle 21 has been detected, the virtual leading vehicle 22 in the state where the predetermined inter-vehicle distance is maintained at the same vehicle speed as that of the preceding preceding vehicle 21 is set behind the preceding preceding vehicle 21 in step S3. . If it is determined in step S1 that the preceding vehicle 23 has not been detected, the process directly returns.
[0019]
After setting the virtual leading vehicle 22 in step S3, a target acceleration candidate At1 for following the preceding vehicle 23 and a target acceleration candidate At2 for following the preceding preceding vehicle 21 are calculated in step S4. In step S5, the target acceleration candidate At1 and the target acceleration candidate At2 are compared, and the smaller one is set as the target acceleration At. After the target acceleration At is set, inter-vehicle distance control is performed based on the target acceleration At in step S6.
[0020]
On the other hand, if it is determined in step S2 that the preceding preceding vehicle 21 has not been detected, the target acceleration At for following the preceding vehicle 23 is calculated in step S7, and the process proceeds to step S6.
[0021]
Therefore, since the inter-vehicle distance control is performed by the smaller target acceleration candidate among the target acceleration candidates for the preceding vehicle 23 and the virtual preceding vehicle 22, the vehicle in which the preceding vehicle 23 repeats frequent acceleration / deceleration or the like. Even if the preceding vehicle 23 suddenly interrupts, smooth inter-vehicle distance control that does not reflect the behavior of the preceding vehicle 23 can be performed. Even if the preceding vehicle 23 suddenly decelerates, the target acceleration candidate decreases as the deceleration increases, so that the target acceleration for following is switched to the target acceleration candidate for the preceding vehicle 23, which is safe. Control becomes possible.
[0022]
In addition, although it is conceivable that the preceding preceding vehicle 21 repeats frequent acceleration / deceleration, in such a case, the preceding vehicle 23 decelerates so as to maintain a safe inter-vehicle distance with respect to the preceding preceding vehicle 21. Therefore, the target acceleration candidate At1 for following the preceding vehicle 23 is reduced, and smooth inter-vehicle distance control can be performed.
[0023]
【The invention's effect】
The present invention detects the inter-vehicle distance from the preceding preceding vehicle by the detecting means, sets a virtual preceding vehicle having the same vehicle speed as the preceding preceding vehicle by the virtual preceding vehicle setting means, and sets the target acceleration candidate for the preceding vehicle and the target for the virtual preceding vehicle. Since the smaller one of the acceleration candidates is set as the target acceleration and the vehicle speed of the host vehicle is controlled, even if the preceding vehicle behaves unfavorably, the inter-vehicle distance control for the virtual preceding vehicle is performed to smoothly move the vehicle speed. Can be controlled. As a result, safe inter-vehicle distance control can be performed without reducing ride comfort.
[Brief description of the drawings]
FIG. 1 is a schematic configuration diagram of a vehicle including a travel control device according to an embodiment of the present invention.
FIG. 2 is a conceptual diagram illustrating virtual preceding vehicle setting.
FIG. 3 is a flowchart of inter-vehicle distance control.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Vehicle 2 Radar means 3 Controller 4 Vehicle speed sensor 5 Engine 6 Brake actuator 7 Lever 8 Handle angle sensor 21 Previous preceding vehicle 22 Virtual preceding vehicle 23 Previous vehicle

Claims (1)

In a vehicle travel control device comprising inter-vehicle distance control means for controlling the vehicle speed of a host vehicle so that the inter-vehicle distance with a preceding vehicle traveling in the same lane as the host vehicle becomes a target inter-vehicle distance, Detection means for detecting the inter-vehicle distance between the preceding vehicle that travels ahead and the host vehicle; virtual preceding vehicle setting means that sets a virtual preceding vehicle that is the same as the vehicle speed of the preceding preceding vehicle behind the preceding preceding vehicle; Preceding vehicle target acceleration candidate calculating means for calculating a target acceleration candidate for following the preceding vehicle; virtual preceding vehicle target acceleration candidate calculating means for calculating a target acceleration candidate for following the virtual preceding vehicle; A target acceleration for setting a target acceleration by selecting a smaller one of a preceding vehicle target acceleration candidate calculated by the vehicle target acceleration candidate calculating means and a virtual preceding vehicle target acceleration candidate calculated by the virtual preceding vehicle target acceleration candidate calculating means. A constant section, the running control device for a vehicle, characterized in that a control means for controlling the speed of the vehicle based on the target acceleration set by the target acceleration setting means.

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