JPH06191321A - Travel control device for vehicle - Google Patents

Abstract

PURPOSE:To identify whether a detected preceding vehicle is a preceding vehicle traveling on a self-vehicle lane or a preceding vehicle traveling on the other vehicle lane accurately to make a follow-up traveling in a travel control device to follow up the preceding vehicle while maintaining an inter-vehicle distance from the preceding vehicle at a specified distance. CONSTITUTION:Information on a preceding vehicle (distance data and azimuth data) detected by a scan laser radar device 10 and information from a vehicle speed sensor 12 and a steer angle sensor 13 are supplied to a micro-computer 18. When the azimuth data of the detected preceding vehicle is approximately zero, the micro-computer 18 recognizes that the vehicle is the preceding vehicle traveling ahead of a self-vehicle with a straight forward extension line from the self-vehicle taken as a reference of azimuth and, based on the distance data and azimuth data of the detected preceding vehicle, it recognizes that the vehicle is a preceding vehicle traveling on the other lane when a distance between the detected preceding vehicle and the self-vehicle forward extension line is over the lane width. In other cases than those above, the self-vehicle lane or the other vehicle lane is judged based on the relative speed between the detected preceding vehicle and the self-vehicle.

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 improving the position identification of a preceding vehicle detected by a radar device.

[0002]

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

In such a traveling control device, a constant speed traveling mode in which the driver cruises the vehicle at a predetermined vehicle speed, and when there is a preceding vehicle, the distance between the preceding vehicle and the preceding vehicle is maintained at a safe distance. However, a follow-up running mode that follows the preceding vehicle is set.

Needless to say, how accurately the preceding vehicle is captured in such a traveling control device is important. For example, a preceding vehicle traveling in an adjacent lane is erroneously recognized as a preceding vehicle on its own lane. If the control is performed, smooth running cannot be performed. Therefore, it is necessary to accurately grasp on which lane the detected preceding vehicle is located.
For example, in the vehicle running control device disclosed in Japanese Patent Laid-Open No. 3-92436, a configuration is proposed in which it is determined that a preceding vehicle offset by a predetermined amount or more from the forward extension of the vehicle is not a preceding vehicle to be followed and the following control is stopped. Has been done.

[0005]

However, in the configuration in which the continuation / stop of the control is judged depending on whether or not the vehicle is offset by a predetermined amount or more from the forward extension, the appropriate control may not always be performed. An example of such a case is shown in FIGS. 6 and 7. First, in FIG. 6, in a two-lane road of an overtaking lane and a traveling lane, the own vehicle is traveling to the left on the traveling lane and the preceding vehicle is traveling to the center on the same traveling lane. Although the preceding vehicle is offset by a predetermined amount or more from the front extension of the own vehicle, the preceding vehicle is traveling in the same lane as the own vehicle.

On the other hand, FIG. 7 shows the case where the host vehicle is running near the center of the traveling lane and the preceding vehicle is running near the center of the overtaking lane. In this case, the offset amount is almost the same as in the case of FIG. 6, but the preceding vehicle is traveling in the overtaking lane which is the adjacent lane, and therefore it is not appropriate to follow this preceding vehicle.

As described above, depending on the traveling positions of the own vehicle and the preceding vehicle in the lane, the preceding vehicle may fall into the same lane or the adjacent lane even with the same offset amount. There is a problem that it is not always possible to reliably determine whether or not a vehicle is a preceding vehicle to follow.

The present invention has been made in view of the above-mentioned problems of the prior art, and an object thereof is to accurately determine whether the preceding vehicle detected by the radar device is in its own lane or in another lane, and smoothly. It is an object of the present invention to provide a vehicle control device that is capable of following and traveling.

[0009]

In order to achieve the above-mentioned object, a vehicle traveling control device of the present invention is a vehicle traveling control that keeps an inter-vehicle distance from a preceding vehicle at a predetermined distance and follows the preceding vehicle. In the device, a radar device that detects an inter-vehicle distance and an azimuth (an offset degree in an orthogonal direction to an extension line of a vehicle center line) with respect to a preceding vehicle, and a detected lane area in which the detected preceding vehicle is determined from a detection range of the radar device. Or a first determining means for determining whether the vehicle is located in another lane area, and a relative speed between the preceding vehicle and the own vehicle when the preceding vehicle is not located in either the own lane area or the other lane area. A second determining means for determining in which area the preceding vehicle is located, and a follow-up run for the preceding vehicle determined to be in the own lane area by the first or second determining means. And determine that it is in another lane area. For been preceding vehicle and having a control means for maintaining the vehicle speed.

[0010]

The vehicle running control of the present invention has such a configuration and discriminates whether the preceding vehicle detected by the two-stage criterion is the preceding vehicle of the own lane or the preceding vehicle of the other lane. .

That is, the inter-vehicle distance and the azimuth (the degree of offset in the orthogonal direction to the extension line of the vehicle center line) with respect to the preceding vehicle are detected by the radar device. Based on this inter-vehicle distance and azimuth, it is determined whether the detected preceding vehicle is located in the own lane area or the other lane area determined from the detection range of the radar device. When the azimuth angle is based on the front extension of the host vehicle, the azimuth angle is near zero, that is, the area on the front extension of the host vehicle is the lane area, and the distance from the front extension determined from the distance and the azimuth angle is The area equal to or larger than the predetermined value is the other lane area. When the detected preceding vehicle falls within these areas, it can be reliably determined to be the preceding vehicle in the own lane or the preceding vehicle in the other lane, but in the case of the preceding vehicle indicating the distance and azimuth between both areas, As mentioned above, it is not always clear on which lane the vehicle is located.

Therefore, the second determining means determines in which area the detected preceding vehicle is located based on the relative speed with respect to the detected preceding vehicle. For example, when the host vehicle is traveling in the traveling lane, the average speed is generally slower than that of a vehicle traveling in the overtaking lane. Therefore, when the speed of the own vehicle with respect to the detected preceding vehicle is slow, it can be determined that the detected preceding vehicle is traveling in the adjacent lane, and when the own vehicle is traveling in the overtaking lane, When the speed of the vehicle is high, it can be determined that the detected preceding vehicle is the preceding vehicle in the adjacent lane. Furthermore, the speed of the own vehicle with respect to the detected preceding vehicle is almost 0,
That is, when traveling at substantially the same speed, it can be determined that the vehicle is traveling on the same lane.

[0013]

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

FIG. 1 is a block diagram showing the configuration of this embodiment. A scan type laser radar device 10 is provided as a radar device at the front of the vehicle. The distance measured by the laser radar is almost 100 m in fine weather, although it varies depending on the weather. Therefore, a vehicle traveling 100 m ahead of the own vehicle is detected as a preceding vehicle. A vehicle speed sensor 12 that optically detects the rotation speed of the drive shaft of the vehicle is provided as vehicle speed detection means. Further, a steering angle sensor 13 for detecting the steering angle of the vehicle is provided on the steering shaft or the like.

Further, an adjusting lever 14 for setting a vehicle speed during constant speed traveling and for adjusting an inter-vehicle distance during follow-up traveling is provided in the driver's seat, and further, a system switch and for switching the inter-vehicle distance during follow-up traveling (in the present embodiment, A distant / middle / near (three stages) changeover switch 16 is also provided in the driver's seat.
The signals from these sensors and switches are supplied to the microcomputer 18.

The microcomputer 18 is equipped with an input / output port, a ROM storing a processing program to be described later, a CPU for performing an operation according to the processing program, a RAM for storing the operation result, and the like. The operation result is stored in the throttle actuator 20 or the brake actuator. Two
2 as a control signal to control the running of the vehicle, and an alarm / display device 24 provided in the driver's seat appropriately displays the current inter-vehicle distance, or warns the driver when the inter-vehicle distance becomes unacceptable. It is a configuration to give.

Here, the scanning type laser radar device 10
The detection range is a fan-shaped region in front of the own vehicle, and depending on the positional relationship with the preceding vehicle, not only the preceding vehicle traveling on the own lane but also the preceding vehicle traveling on the adjacent lane may be detected. If the preceding vehicle in the adjacent lane is erroneously recognized as the preceding vehicle to be followed, and the follow-up running is performed, the acceleration / deceleration unnecessary for the driver is performed, and the smooth running cannot be performed.
Therefore, in the present embodiment, the microcomputer 18
The following two-stage determination processing is performed to determine whether the detected preceding vehicle is the preceding vehicle of the own lane or the preceding vehicle of another lane. That is, (1) which one of the own lane area and the other lane area determined by the detection range of the scanning laser radar 10 corresponds to the detected preceding vehicle. (2) When the detected preceding vehicle is not located in any area. It is determined in which area the detected preceding vehicle is located based on the relative speed between the detected preceding vehicle and the own vehicle.

FIG. 2 shows the own lane area (A area), and FIGS. 3 and 4 show the other lane area (B area). The own lane area is a specific area within the radar detection range, and all the preceding vehicles detected in this area can be determined as the preceding vehicles in the own lane. When the azimuth angle reference (origin) is on the extension line of the front of the host vehicle, the region where the azimuth angle of the detected preceding vehicle is almost 0 is the host lane region (see FIG. 2).

On the other hand, the other lane area is a specific area within the radar detection range, and all the preceding vehicles detected in this area can be determined as the preceding vehicles traveling in the other lane. FIG. 3 shows another lane area when the vehicle is traveling in each of the positions a, b, and c in the lane having the lane width L (hatched portion in FIG. 3). As shown in FIG. 4, the condition of the region B for determining the detected preceding vehicle as the preceding vehicle in the other lane regardless of where the own vehicle is traveling is as shown in FIG. This is an area where the distance from the line is equal to or larger than the lane width L. Therefore, the microcomputer 18 determines the azimuth angle data θ based on the distance data 1 and the azimuth angle data θ detected by the scanning laser radar device 10.
Is a small value equal to or smaller than a predetermined value, it is determined whether or not it is in the area A, and the distance l · si from the extension line in front of the vehicle is determined.
Whether or not it is the B region is determined depending on whether or not nθ is equal to or larger than the lane width L.

However, there is a case where the detected preceding vehicle does not correspond to either the area A or the area B. In this case, it is not possible to discriminate whether the detected preceding vehicle is the preceding vehicle of the own lane or another preceding vehicle only by the distance data and the azimuth data.
Therefore, the process shifts to the determination of (2) above, and it is determined which of the preceding vehicles is based on the relative speed with respect to the detected preceding vehicle. If the preceding vehicle and the own vehicle are traveling on the same lane, there is no significant difference in their relative speeds, and if the own vehicle is traveling in the traveling lane and the preceding vehicle is traveling in the overtaking lane, or When the own vehicle is traveling in the overtaking lane and the preceding vehicle is traveling in the traveling lane, there is a large difference in the speed difference. Therefore, it is possible to identify whether the detected preceding vehicle is the preceding vehicle in the own lane or the preceding vehicle in the other lane based on the relative speed.

Based on the above principle, the microcomputer 18 judges whether the detected preceding vehicle is the preceding vehicle of the own lane or the preceding vehicle of another lane, and if it is judged that the preceding vehicle is the preceding lane of the own lane, it should follow this preceding vehicle. The throttle actuator 20 is controlled to follow the vehicle, and if it is determined that the vehicle is in the other lane, the vehicle does not follow the preceding vehicle and the throttle opening is kept constant to maintain the current vehicle speed.

FIG. 5 shows a more detailed processing flow chart of the microcomputer 18. First, the magnitude of the steering angle ST detected by the steering angle sensor 13 and the predetermined value ST0 are compared (S100). This determination is a process for determining whether or not the vehicle is traveling on a curved road, and when the steering angle ST is larger than a predetermined value ST0, it is determined that the vehicle is traveling on the curved road, The process shifts to the determination process in (S200). A known technique is used for the detection of the preceding vehicle on the curved road, and the determination is made based on the steering angle, the vehicle speed, and the azimuth angle of the radar device. Then, Va and Vb are reset (Va and Vb will be described later).

On the other hand, when the vehicle is traveling on a straight road, the process proceeds to the area determination process of the detected preceding vehicle based on the distance data and the azimuth data from the radar device 10 described above (S).
100). That is, first, it is determined whether the detected preceding vehicle is located in the area A (S120). This determination is made based on whether or not the azimuth angle of the detected preceding vehicle is near zero. When it is determined that the detected preceding vehicle is located in the area E, the detected preceding vehicle is recognized as a preceding vehicle traveling in the same lane as the own lane (S300), and the latest several preceding vehicles (3
The average vehicle speed Va of the detected preceding vehicles located in the area A of 10 to 10 vehicles is calculated. When the own vehicle is traveling in the traveling lane, this average vehicle speed Va corresponds to the average vehicle speed in the traveling lane, and when the own vehicle is traveling in the overtaking lane,
It corresponds to the average vehicle speed in the passing lane. When the azimuth angle of the detected preceding vehicle is equal to or greater than the predetermined value, it is determined that the detected preceding vehicle is not in the area A, and then it is determined whether the detected preceding vehicle is located in the area B (S130). This determination is made based on the distance data and azimuth data of the detected preceding vehicle, as described above, based on whether or not the distance from the front extension line of the vehicle is equal to or larger than the lane width. When it is determined that the detected preceding vehicle is located in the B area, the detected preceding vehicle is recognized as a preceding vehicle traveling on another lane (S400), and the detected preceding vehicle is located in the B area as in S310. Then, the average vehicle speeds Vb of several detected preceding vehicles determined to be calculated are calculated (S410).

On the other hand, depending on the distance data and azimuth data of the detected preceding vehicle, it may be determined that the vehicle is not located in either the area A or the area B. In this case, it is first determined whether or not the average vehicle speeds Va and Vb are fixed (S).
140). In the state where the above-described processing of S310 to S410 is not performed and the average vehicle speeds Va and Vb are not yet determined, the relative speed Vrr obtained by differentiating the distance data of the detected preceding vehicle and the predetermined value Vrr0 are compared. Done (S
500). When the own vehicle and the detected preceding vehicle are traveling in the same lane, there is no significant difference in their relative speeds.When the own vehicle is in the traveling lane and the detected preceding vehicle is in the overtaking lane, or Is a passing lane, and when the detected preceding vehicle is traveling in the traveling lane, the average vehicle speed in the overtaking lane is generally higher than the average vehicle speed in the traveling lane, so that there is a large difference in relative speed. Therefore, as a result of comparison of the relative speed Vrr and the predetermined value Vrr0,
If it is less than or equal to the predetermined value, it is determined that the detected preceding vehicle is the preceding vehicle in its own lane (S510), and if it is greater than or equal to the predetermined value, it is determined that it is the preceding vehicle in another lane (S520). When the average vehicle speeds Va and Vb are confirmed, the detected preceding vehicle is discriminated using this average vehicle speed. As described above, it is possible to determine whether the detected preceding vehicle is the own lane or another lane depending on the relative speed with respect to the detected preceding vehicle.However, in this determination, the average vehicle speed between the traveling lane and the overtaking lane is generally used. It is supposed to be different. However, it is well known that the average speed difference between the overtaking lane and the driving lane changes depending on the road condition, and therefore, in the process of comparing the relative speed with the predetermined value, the detected preceding vehicle is not necessarily detected in all road conditions. Is not always accurately identified. Therefore, the average vehicle speed V that reflects the actual driving situation
By making a determination using a and Vb, the accuracy of identifying the detected preceding vehicle is further improved. Identification of the detected preceding vehicle using Va and Vb in this embodiment is performed as follows. That is, first, the magnitude comparison between the average vehicle speed Va in the area A and the average vehicle speed Vb in the area B is performed (S150). V
If a is larger than Vb, that is, the average vehicle speed in the own lane area is larger than the average vehicle speed in the other lane area, it can be determined that the own vehicle is currently traveling in the overtaking lane. And
The magnitude Vs of the detected preceding vehicle speed Vs calculated from the relative speed Vrr and the own vehicle speed V and the average vehicle speed Vb are compared (S60).
0), if the detected preceding vehicle is slower than the average vehicle speed Vb in the other lane, it is determined to be the preceding vehicle in the other lane (S620), and the others are determined to be the preceding vehicles in the own lane (S610). If the average vehicle speed Va is smaller than the average vehicle speed Vb, it is determined that the host vehicle is traveling in the traveling lane, and the magnitude Vs of the detected preceding vehicle and the average vehicle speed Vb are compared (S160). ). If the detected preceding vehicle is faster than the average vehicle speed Vb, that is, the average vehicle speed of the overtaking lane, it is determined to be a preceding vehicle in another lane (S180), and otherwise it is determined to be a preceding vehicle in the own lane (S170).

In this way, the detected preceding vehicle is located in the own lane area or in the other lane area by comparing the average vehicle speed in the own lane area with the average vehicle speed in the other lane area and the speed of the detected preceding vehicle. Can be identified more reliably.

As a result of such determination, when the detected preceding vehicle is the preceding vehicle in the own lane (S700), the throttle distance is maintained in order to maintain the following distance between the detected preceding vehicle and the safe preceding distance calculated from the own vehicle speed. When the detected preceding vehicle is determined to be a preceding vehicle in another lane, the current vehicle speed is not followed and the current vehicle speed is changed to the following vehicle speed by controlling the actuator 20 to perform following traveling (vehicle distance control) (S720). Control to maintain is performed (S710). Therefore, in the travel control device according to the present embodiment, by following the preceding vehicle in the other lane, it is possible to prevent the situation in which acceleration / deceleration unnecessary for the driver is performed.
You can continue comfortable and smooth following.

[0027]

As described above, according to the vehicle travel control device of the present invention, it is possible to determine with high accuracy whether the detected preceding vehicle is the preceding vehicle of the own lane or the preceding vehicle of the other lane, and the preceding lane of the own lane is advanced. Since control is performed to follow only the vehicle, comfortable and smooth follow-up travel can be performed without performing unnecessary acceleration / deceleration control for the driver.

[Brief description of drawings]

FIG. 1 is a configuration block diagram according to an embodiment of the present invention.

FIG. 2 is an explanatory diagram of an own lane area in the embodiment.

FIG. 3 is an explanatory diagram of another lane area in the embodiment.

FIG. 4 is an explanatory diagram of another lane area in the embodiment.

FIG. 5 is a processing flowchart of the microcomputer in the embodiment.

FIG. 6 is an explanatory diagram showing a relative positional relationship between a host vehicle and a preceding vehicle.

FIG. 7 is an explanatory diagram showing a relative positional relationship between a host vehicle and a preceding vehicle.

[Explanation of symbols]

 10 Laser Radar Device 12 Vehicle Speed Sensor 13 Steering Angle Sensor 14 Adjustment Lever 16 System Switch 18 Microcomputer 20 Throttle Actuator 22 Brake Actuator 24 Alarm / Display Device

Claims (1)

[Claims] 1. A vehicle travel control device for keeping a vehicle-to-vehicle distance to a preceding vehicle at a predetermined distance to follow the preceding vehicle, a radar device for detecting a vehicle-to-vehicle distance and a direction to the preceding vehicle, and a detected preceding vehicle. First determining means for determining whether the vehicle is located in the own lane area or another lane area determined from the detection range of the radar device; and the preceding vehicle is located in both the own lane area and the other lane area. When the vehicle is not located, a second determination unit that determines in which region the preceding vehicle is located based on the relative speed between the preceding vehicle and the own vehicle, and the own lane region by the first or second determination unit For a vehicle characterized by having a control means for performing follow-up traveling with respect to a preceding vehicle determined to be in the following lane and maintaining the own vehicle speed with respect to a preceding vehicle determined to be in another lane area. Travel control device.