JP2778327B2 - Travel control device for vehicles - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a traveling control device for a vehicle, and more particularly to a control device for following a preceding vehicle while maintaining a substantially constant inter-vehicle distance to the preceding vehicle.

[0002]

2. Description of the Related Art Conventionally, a traveling control device for automatically adjusting the speed of a vehicle has been developed for the purpose of reducing driving operation and improving safety on a highway.

[0003] In such a traveling control device, a constant speed traveling mode in which the driver cruises the vehicle at a preset vehicle speed, or when a preceding vehicle exists, the inter-vehicle distance to the preceding vehicle is maintained at a safe distance. A follow-up running mode for following the preceding vehicle while the vehicle is running is set.

Here, in the following running mode, vehicle speed control is performed so that the current inter-vehicle distance matches a predetermined or calculated target inter-vehicle distance based on the vehicle speed. Since the appropriate inter-vehicle distance varies depending on conditions, the target inter-vehicle distance is not always appropriate. For example, the inter-vehicle distance may be too large with respect to the traffic volume of the vehicle, and an interruption from an adjacent lane may occur. .

[0005] When another vehicle interrupts between the preceding vehicle and the own vehicle, the interrupted vehicle becomes the preceding vehicle to be newly followed, and the inter-vehicle distance becomes smaller than the target inter-vehicle distance. Then, sudden deceleration is performed, and the driver feels discomfort.

Accordingly, for example, Japanese Patent Application Laid-Open No. Sho 60-131327
In Japanese Patent Application Laid-Open Publication No. H11-264, a configuration is proposed in which, when another vehicle interrupts during follow-up running, the current vehicle speed is maintained for a predetermined time, and then acceleration / deceleration control is performed in accordance with the relative speed to the interrupted vehicle.

[0007] However, even in such follow-up traveling, although rapid deceleration at the time of interruption can be prevented, there is a high possibility that another vehicle will again interrupt while traveling following the interrupted vehicle. When the vehicle is interrupted by the vehicle, there is a problem that the vehicle is delayed more and more and the driver cannot drive as intended.

Accordingly, the applicant of the present application has previously filed Japanese Patent Application No. Hei.
In No. 4606, it is detected that an interruption has occurred from the change in the inter-vehicle distance, and if the number of interruptions within a predetermined time is equal to or more than a predetermined number, the current target inter-vehicle distance must be an appropriate inter-vehicle distance along the flow of the vehicle. Judgment, proposed a configuration that automatically corrects the target inter-vehicle distance to an appropriate inter-vehicle distance by correcting the target inter-vehicle distance.

[0009]

In this manner, the number of interrupts is detected, and when there are many interrupts, the target inter-vehicle distance is shortened and corrected to prevent the vehicle from being interrupted any more. It is possible to prevent the vehicle from moving forward, but in actual driving in which the driver operates the vehicle by himself, the inter-vehicle distance between the own vehicle and the preceding vehicle is adjusted after actually interrupting in this way Rather, in many cases, the possibility of interruption is evaluated based on the traffic volume of vehicles in the adjacent lane, and if the possibility of interruption is high, the inter-vehicle distance to the preceding vehicle is often adjusted beforehand.

[0010] Therefore, for the driver, the configuration in which the inter-vehicle distance is adjusted after the interruption actually occurs a predetermined number of times does not match the driving feeling of the driver, and a comfortable traveling cannot always be guaranteed. was there.

The present invention has been made in view of the above-mentioned conventional problems, and its object is to match the actual driving feeling by predicting the presence or absence of an interruption from the traffic volume of an adjacent lane and adjusting the inter-vehicle distance beforehand. It is an object of the present invention to provide a vehicle travel control device capable of performing comfortable following travel.

[0012]

In order to achieve the above object, a vehicular traveling control device according to the present invention, as shown in FIG. 1, detects a preceding vehicle traveling in its own lane and an adjacent lane. 1, distance detecting means 2 for detecting a distance to a preceding vehicle based on a detection signal from the radar device 1,
A relative speed detecting means 3 for detecting a relative speed with respect to a preceding vehicle based on a detection signal from the radar device 1, and an average inter-vehicle calculating an average inter-vehicle distance between a predetermined number of preceding vehicles traveling in an adjacent lane based on the relative speed; It is characterized by having distance calculating means 4 and control means 5 for controlling a throttle to increase or decrease the inter-vehicle distance with a preceding vehicle traveling on the own lane based on the average inter-vehicle distance.

[0013]

The vehicle travel control device of the present invention has the above-described structure. Instead of calculating the target inter-vehicle distance based on the own vehicle speed and controlling the inter-vehicle distance as in the prior art, the average of adjacent lanes is used. The traffic amount of the adjacent lane is evaluated from the inter-vehicle distance, and the inter-vehicle distance to the preceding vehicle is increased or decreased based on the traffic light amount of the adjacent lane.

For example, when the vehicle is traveling in a traveling lane on a two-lane road, the passing lane, which is an adjacent lane, has a small traffic amount in a normal state. However, when the traffic volume in the overtaking lane increases, the passing lane increases. The possibility of interruption to the driving lane increases.

Therefore, the traffic in the passing lane is evaluated based on the average inter-vehicle distance, and when the average inter-vehicle distance is small, it is determined that the traffic is large, and the inter-vehicle distance between the own vehicle and the preceding vehicle is reduced, thereby passing the vehicle. Interruption from the lane to the traveling lane is prevented beforehand, and the vehicle can smoothly follow the traveling lane.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of a vehicle travel control device according to the present invention will be described below with reference to the drawings.

FIG. 2 is a block diagram showing the configuration of this embodiment. Three distance measuring sensors 10, 1 such as laser radar
2 and 14 are provided in front of the vehicle, and irradiate three spots of laser light to the front and side to detect the preceding vehicle in the own lane and the adjacent lane and measure the distance. Of course, instead of using the three laser radars, the laser beam from one laser radar may be scanned left and right (scanned laser radar device) to detect the preceding vehicle.

The distance signals from the three distance measuring sensors 10, 12, and 14 are input to an inter-vehicle control computer 16, where the time derivative is calculated to detect the relative speed. The vehicle speed detected by the vehicle speed sensor 18 is also used by the computer 16.
Is input to

The inter-vehicle control computer 16 calculates a target inter-vehicle distance LT0 from the preceding vehicle in the lane from the distance data, the vehicle speed data and the relative speed data, and sets the throttle actuator 20 of the own vehicle so that the inter-vehicle distance becomes the target inter-vehicle distance. Is controlled, and the target inter-vehicle distance is corrected to increase or decrease by evaluating the traffic amount of the adjacent lane.

Hereinafter, the processing performed by the headway distance control computer 16 will be described in detail with reference to the flowchart of FIG.

When the control is started, the inter-vehicle control computer 16 first calculates an original target inter-vehicle distance LT0 from the preceding vehicle based on the own vehicle speed. A known method is used for the calculation of the original target inter-vehicle distance. In this embodiment, the original target inter-vehicle distance LT0 is calculated as follows: LT0 = α × vehicle speed−β × relative speed (α,
β: constant) (S101).

Next, it is determined whether or not there is a preceding vehicle in the right adjacent lane based on the distance data from the right distance measuring sensor 10 (S102). Effective range of laser radar is approx. 1
Since it is 00 m, if a preceding vehicle exists in the lane adjacent to the right within 100 m, the preceding vehicle can be recognized. And if there is a preceding vehicle in the right lane,
It is determined that the host vehicle is traveling in the traveling lane, and the flag FL indicating traveling lane traveling is set to 1 (S103).

The average inter-vehicle distance of the preceding vehicle group traveling in the overtaking lane is calculated in order to evaluate the traffic of the preceding vehicle traveling on the right lane, ie, the overtaking lane.

FIG. 4 is a vehicle layout diagram for explaining the calculation of the average inter-vehicle distance. In the figure, it is assumed that at time t = 0, the vehicle 100 travels in the traveling lane, and the vehicle 1 is traveling L = L0 away from the passing lane, which is the right adjacent lane. Further, it is assumed that the vehicle 2 is traveling behind the vehicle 1 in the overtaking lane. It is assumed that the vehicle 1 is traveling at the speed VN1 and the vehicle 2 is traveling at the speed VN2. Then, after the time t = Δt, the own vehicle has L = VN0 · Δt
It is assumed that the vehicle 2 on the overtaking lane overtakes the own vehicle and the distance from the own vehicle becomes L = L0 again. At this time, the inter-vehicle distance Ln between the vehicle 1 and the vehicle 2 on the overtaking lane
From the figure, Ln = (L0 + VN1..DELTA.t)-(L0 + VN0..DELTA.t) = (VN1-VN0) .. DELTA.t = VRR.DELTA.t where VRR is the relative speed between the own vehicle and the vehicle 1. As described above, the inter-vehicle distance between the vehicle 1 and the vehicle 2 on the overtaking lane is determined by using the relative speed between the own vehicle and the vehicle 1 and the time Δt required until the own vehicle and the vehicle 2 are separated by a distance L = L0. Can be calculated. Therefore, the distance control computer 16
By measuring the relative speed VRR obtained by time-differentiating the distance data obtained from the right distance measurement sensor 10 and the time Δt required for the vehicle 2 to separate from the own vehicle by L0,
The inter-vehicle distance Ln between the vehicle 1 and the vehicle 2 on the passing lane is calculated (S105).

Then, in order to evaluate the amount of traffic on the passing lane, the inter-vehicle distance Ln on the overtaking lane is determined for a predetermined number, for example, k + 1 vehicles, and the average LR of these inter-vehicle distances is obtained.
Is calculated (S106). The average inter-vehicle distance LR is a parameter indicating the amount of traffic in the overtaking lane. That is,
The average inter-vehicle distance LR decreases when the number of vehicles traveling in the overtaking lane is large and the traffic volume is large, and conversely when the traffic volume is small, the average inter-vehicle distance LR is large.

After the traffic on the right lane, that is, the passing lane, is evaluated in the above manner, the same process is performed on the left adjacent lane. When the vehicle is traveling in the traveling lane, there is no vehicle in the adjacent lane to the left, but when the vehicle is traveling in the overtaking lane, the vehicle traveling in the traveling lane is detected by the left ranging sensor 14. Will be detected. Then, when the vehicle is detected in the left adjacent lane, the same processing as in the case of detecting the vehicle in the right adjacent lane is performed (S107 to S111). That is, the inter-vehicle distance Ln of the vehicle on the traveling lane is calculated from the relative speed between the vehicle and the vehicle traveling in the left adjacent lane, that is, the vehicle traveling in the traveling lane, and the required time Δt required to reach the predetermined distance L0. Calculate the average value LL of the number of vehicles. This average inter-vehicle distance LL is also a parameter for evaluating the traffic volume of the vehicle on the traveling lane, like LR described above.

After the traffic volume of vehicles on the right and left adjacent lanes adjacent to the own lane is evaluated, the inter-vehicle distance between the own vehicle and the preceding vehicle on the own lane is adjusted according to the evaluation result. Do. Generally, the inter-vehicle distance differs between when the vehicle is traveling in the traveling lane and when the vehicle is traveling in the overtaking lane. That is, the overtaking lane is exactly the lane for overtaking, and therefore, the inter-vehicle distance on the overtaking lane is generally larger than the inter-vehicle distance on the traveling lane. Thus, in the present embodiment, different inter-vehicle distance processing is performed when the own vehicle is traveling on the traveling lane and when the own vehicle is traveling on the passing lane.

That is, first, it is determined whether or not the own vehicle is traveling on the traveling lane. As described above, when the vehicle is traveling on the traveling lane, the flag FL is set to 1. Therefore, by detecting the value of the flag FL, it is determined whether or not the own vehicle is traveling on the traveling lane. Can be determined (S112). When it is determined that the vehicle is traveling on the traveling lane, the target inter-vehicle distance LT with the preceding vehicle is determined.
Is determined using the average inter-vehicle distance LL of the overtaking lane calculated above to set LT = αLR 0 <α <1 (S113). Since α is smaller than 1, the target inter-vehicle distance LT obtained in this way is smaller than the average inter-vehicle distance LR in the passing lane, and matches the magnitude relationship between the inter-vehicle distance in the actual traveling lane and the inter-vehicle distance in the overtaking lane. It is the distance between vehicles.

On the other hand, the flag FL is not 1, ie, 0
Is set, the value of the flag FR is detected next. As described above, when the vehicle is detected by the left distance measurement sensor 14, it is determined that the own vehicle is traveling in the passing lane, and the flag FR is set to 1. Therefore,
When the own vehicle is traveling on the passing lane, the flag FR is determined to be 1, and the target inter-vehicle distance is calculated by LT = 1 / α · LL (S114). LL is the average inter-vehicle distance of the vehicle traveling in the traveling lane. Therefore, the inter-vehicle distance of the own vehicle traveling in the overtaking lane is determined according to the average inter-vehicle distance on this traveling lane, and α is smaller than 1. Considering this, an inter-vehicle distance larger than the average inter-vehicle distance on the traveling lane is set as the target inter-vehicle distance.

As described above, when the own vehicle is traveling in the traveling lane, the inter-vehicle distance between the own vehicle and the preceding vehicle is determined based on the average inter-vehicle distance of the overtaking lane. If it is determined that the vehicle is running on the driving lane, the vehicle-to-vehicle distance is determined based on the average vehicle-to-vehicle distance, and then the magnitude is compared with the original target vehicle-to-vehicle distance LT0 calculated based on the normal vehicle speed (S115). ). The original target inter-vehicle distance LT0 is the target inter-vehicle distance LT corresponding to the traffic amount of the adjacent lane.
If it is smaller, the original target inter-vehicle distance LT0 is adopted to control the throttle of the own vehicle.
If T is smaller, throttle control is performed so as to match this target inter-vehicle distance LT.

In the conventional device, the original target inter-vehicle distance LT
Since 0 is determined regardless of the traffic volume of the adjacent lane,
For example, if the own vehicle is traveling in the traveling lane and the traffic in the overtaking lane is large, the number of vehicles interrupting from the overtaking lane to the traveling lane will increase, but in this way a new target inter-vehicle distance according to the traffic in the overtaking lane LT is calculated, and the original target inter-vehicle distance LT is calculated.
When it is smaller than 0, the target inter-vehicle distance LT is adopted as the target inter-vehicle distance, whereby the inter-vehicle distance between the own vehicle and the preceding vehicle is reduced in accordance with the amount of traffic on the overtaking lane. And the vehicle can smoothly and comfortably follow the vehicle in the traveling lane.

[0032]

As described above, according to the vehicle travel control apparatus of the present invention, the average inter-vehicle distance of vehicles traveling in the adjacent lane is calculated to evaluate the traffic in the adjacent lane, and the evaluation result is obtained. Therefore, the distance between the vehicle and the preceding vehicle in the own lane is adjusted in accordance with the vehicle speed, so that a frequent interruption from the adjacent lane to the own lane can be prevented beforehand, and the vehicle can follow smoothly.

[Brief description of the drawings]

FIG. 1 is a configuration block diagram of a vehicle travel control device according to the present invention.

FIG. 2 is a configuration block diagram of one embodiment of the present invention.

FIG. 3 is a processing flowchart of the embodiment.

FIG. 4 is an explanatory diagram showing a positional relationship between the host vehicle and a vehicle traveling in an adjacent lane in the embodiment.

[Explanation of symbols]

 10, 12, 14 Distance sensor 16 Vehicle control computer 18 Vehicle speed sensor 20 Throttle actuator

Continued on the front page (51) Int.Cl. ⁶ Identification code FI G08G 1/16 G08G 1/16 A

Claims (1)

(57) [Claims] 1. A radar device for detecting a preceding vehicle traveling in the own lane and an adjacent lane, a distance detecting means for detecting a distance to the preceding vehicle based on a detection signal from the radar device, and a detection from the radar device A relative speed detecting means for detecting a relative speed with respect to a preceding vehicle based on the signal; an average inter-vehicle distance calculating means for calculating an average inter-vehicle distance between a predetermined number of preceding vehicles traveling in an adjacent lane based on the relative speed; and Control means for controlling a throttle so as to increase or decrease the inter-vehicle distance with a preceding vehicle traveling on the own lane based on the distance.