JP2001270344A - Vehicle travel controller - Google Patents

Abstract

PROBLEM TO BE SOLVED: To automatically specify a vehicle to be followed up. SOLUTION: When a specified vehicle is not set, a constant speed travel control for traveling at a constant speed is performed so that a vehicle speed becomes a preset vehicle speed. When an advance vehicle is detected on a vehicle traveling lane when a specified vehicle is not set, the advance vehicle is set to the specified vehicle, the specified vehicle is followed up based on the results of measurement of a vehicle-to-vehicle distance and a bearing, and a specified vehicle follow-up control to follow up the specified vehicle while maintaining the vehicle-to-vehicle distance at a constant is performed as far as the vehicle is within the range of the measurement of vehicle-to-vehicle distance and bearing. Thus, a vehicle to be followed up can be specified automatically, and such an existing troublesome operation that a vehicle to be followed up must be specified manually by an input device during the operation can be eliminated.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a travel control device for a vehicle for automatically specifying a vehicle to be followed and controlling the speed of the own vehicle so as to maintain a safe inter-vehicle distance.

[0002]

2. Description of the Related Art An inter-vehicle distance to a preceding vehicle is measured by a distance measuring device, an image of the front of the vehicle is taken by an image pickup device, and a vehicle desired to be followed by an input device is specified from a plurality of preceding vehicles in a preceding image of the vehicle. A vehicle running control device is known as a vehicle to be followed as long as the specific vehicle is within the measurement range of the distance measuring device (for example, see Japanese Patent Application Laid-Open No. 10-86698).

[0003] According to this device, it is possible to select a preceding vehicle on the traveling lane (lane) of the own vehicle or a preceding vehicle on an adjacent lane as a specific vehicle. When the following control is started, as long as the specific vehicle is within the measurement range of the distance measuring device, the following control is continued regardless of whether the vehicle is on the own vehicle traveling lane or on an adjacent lane. Such follow-up control is called "specific vehicle follow-up control" or "lock-on control", and this specific vehicle is called "lock-on vehicle".

Further, the distance between the vehicle and the preceding vehicle is measured by a distance measuring device, the road shape is estimated based on the steering angle of the own vehicle, etc., and the preceding vehicle on the own vehicle running lane is detected. When there is no preceding vehicle above, constant vehicle speed control is performed so that the vehicle travels at a constant vehicle speed.When there is a preceding vehicle on the own vehicle traveling lane, follow-up control is performed while maintaining a constant inter-vehicle distance with the preceding vehicle. There is known a vehicle travel control device that performs the following (for example, see Japanese Patent Application Laid-Open No. 6-191321).

In the latter device, when there is a preceding vehicle on the own vehicle's running lane, the inter-vehicle distance control is performed as a vehicle to be followed regardless of whether or not the preceding vehicle is to be followed. When the vehicle speed is increased, the following control is performed. However, when the preceding vehicle on the own vehicle traveling lane is out of the measurement range of the distance measuring device, the vehicle is switched to the constant vehicle speed control in which the vehicle travels at a constant vehicle speed. In this specification, such follow-up control is referred to as "inter-vehicle distance control type constant speed automatic cruise control" or simply "ACC (Adaptive Cruise)".
Control).

[0006]

However, the former vehicle travel control device has a problem that the operation is complicated because the vehicle to be followed must be specified by the input device during driving.

An object of the present invention is to automatically specify a target vehicle to be followed.

[0008]

FIG. 1 shows an embodiment of the present invention.
The present invention will be described with reference to the following. (1) The invention according to claim 1 includes a measuring means 1 for measuring an inter-vehicle distance and an azimuth to a vehicle ahead of the own vehicle, a steering angle detecting means 3 for detecting a steering angle, and A preceding vehicle detecting means 8 for detecting a preceding vehicle on the own vehicle traveling lane based on the measured values of the inter-vehicle distance and azimuth and the detected steering angle; and a vehicle traveling lane when no specific target vehicle is set. When the preceding vehicle is detected above, the vehicle specifying means 8 sets the preceding vehicle as the specific vehicle, and when the specific vehicle is set, the specific vehicle is tracked based on the measurement results of the inter-vehicle distance and the azimuth. The specific vehicle follow-up control unit 4 that follows the specific vehicle while keeping the inter-vehicle distance constant as long as the vehicle is within the measurement range of the measurement unit 1, the own vehicle speed detection unit 2 that detects the own vehicle speed, and the specific vehicle is not set. When the vehicle speed is set in advance, And a cruise control means (4) for constant speed running so that the vehicle speed, thereby achieving the above object. (2) The vehicle running control device according to claim 2, when the preceding vehicle is detected on the own vehicle running lane when the specific vehicle being tracked is lost by the vehicle specifying means 8, the preceding vehicle is replaced with a new specific vehicle. Is set to. (3) The invention according to claim 3 is a measuring means 1 for measuring an inter-vehicle distance and a direction to a vehicle ahead of the own vehicle, a steering angle detecting means 3 for detecting a steering angle, a measured value of the inter-vehicle distance and a direction, and steering. Preceding vehicle detecting means 8 for detecting a preceding vehicle on the own vehicle traveling lane based on the detected angle value; and detecting a preceding vehicle on the own vehicle traveling lane when the preceding vehicle is detected on the own vehicle traveling lane. Preceding vehicle following control means 4 for following the preceding vehicle;
Own vehicle speed detecting means 2 for detecting the own vehicle speed, and constant speed traveling control means 4 for traveling at a constant speed so that the own vehicle speed becomes a preset vehicle speed when no preceding vehicle is detected on the own vehicle traveling lane. The present invention is applied to a vehicle travel control device provided with And
When the preceding vehicle following control is continuously performed for the same preceding vehicle on the own vehicle traveling lane for a predetermined time, the vehicle specifying means 8 sets the preceding vehicle as the specific vehicle of the following target; When set, the specific vehicle follow-up control means 4 which tracks the specific vehicle based on the measurement result of the inter-vehicle distance and the azimuth and follows the specific vehicle while keeping the inter-vehicle distance constant as long as it is within the measurement range of the measuring means 1; To achieve the above object. (4) The vehicle running control device according to claim 4 predicts the current position of the preceding vehicle on the own vehicle running lane by the vehicle specifying means 8 based on the previous measurement result of the measuring means 1, and When the preceding vehicle is detected by the preceding vehicle detecting means 8 around the predicted position at the time of the measurement, the preceding vehicle at the time of the previous measurement and the preceding vehicle at the time of this measurement are determined to be the same.

In the section of the means for solving the above-described problem, a diagram of one embodiment is used for easy understanding of the description, but the present invention is not limited to the embodiment. .

[0010]

(1) According to the first aspect of the present invention, when a specific vehicle is not set, a constant speed running control for performing a constant speed running so that the own vehicle speed becomes a preset vehicle speed is performed. If a preceding vehicle is detected on the own vehicle's driving lane when no vehicle is set, the preceding vehicle is set as a specific vehicle, the specific vehicle is tracked based on the measurement result of the following distance and azimuth, and the specific vehicle is tracked. Even if the vehicle goes out of the vehicle lane, the specific vehicle following control is performed to follow the specific vehicle while keeping the inter-vehicle distance constant as long as it is within the measurement range of the inter-vehicle distance and azimuth. It is possible to automatically specify the target target vehicle by the input device during driving as in the case of the conventional device. (2) According to the invention of claim 2, when a preceding vehicle is detected on the own vehicle traveling lane when the specific vehicle being tracked is lost, the preceding vehicle is set as a new specific vehicle. The same effects as those of the first aspect can be obtained. (3) According to the invention of claim 3, when the preceding vehicle follow-up control is continuously performed for the same preceding vehicle on the own vehicle traveling lane for a predetermined time, the preceding vehicle is set as the target vehicle to be followed. To perform a specific vehicle tracking control that tracks a specific vehicle based on the measurement results of the inter-vehicle distance and azimuth, and follows the specific vehicle while keeping the inter-vehicle distance constant as long as it is within the measurement range of the inter-vehicle distance and azimuth. Therefore, accidentally locking on a fixed object such as a vehicle running in the next driving lane on a curved road or a signboard beside the road, or locking on to a preceding vehicle with a slower vehicle speed contrary to the driver's will Can be avoided and an appropriate preceding vehicle can be locked on as a target to be followed. (4) According to the invention of claim 4, the current position of the preceding vehicle on the own vehicle traveling lane is predicted based on the previous measurement result of the inter-vehicle distance and the azimuth, and the predicted position is determined at the time of the current measurement of the inter-vehicle distance and the azimuth. When a preceding vehicle is detected in the vicinity, it is determined that the preceding vehicle at the time of the previous measurement is the same as the preceding vehicle at the time of this measurement. Accurate detection is possible, and it is possible to reliably lock on the intended preceding vehicle.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Specific vehicle following control (lock-on control) and inter-vehicle distance control type constant speed automatic cruise control (ACC control)
An embodiment of the present invention will be described in which the following is used in combination to automatically specify the vehicle to be followed and perform the following control, and when the vehicle to be followed cannot be specified, to perform constant speed control.

<< First Embodiment of the Invention >> FIG. 1 is a diagram showing a configuration of a first embodiment. The distance measuring device 1
The laser radar measures the distance l (t) and the azimuth φ (t) to an object in front of the vehicle. In addition, the distance measuring device 1 is not limited to a laser radar, and may use a radio wave radar, a camera, or the like. The vehicle speed detecting device 2 detects the rotational speed of the wheel and converts it into the running speed v (t) of the own vehicle.
The steering angle detecting device 3 detects the rotation angle of the steering wheel and converts it into a steering angle θ.

The ACC controller 4 is composed of a CPU and its peripheral parts. When there is no vehicle to be followed, the ACC controller 4 performs constant speed running control with the set vehicle speed Vs as a target vehicle speed. When there is a vehicle to be followed, an appropriate inter-vehicle distance Ls is calculated based on the set inter-vehicle distance and relative speed, a target vehicle speed is determined with the set vehicle speed Vs as an upper limit so as to maintain the appropriate inter-vehicle distance Ls, and vehicle speed control is performed. .

Note that the specific vehicle (lock-on vehicle) is a vehicle to be followed during the above-mentioned specific vehicle following control (lock-on control), and the vehicle on the own vehicle traveling lane during the above-mentioned preceding vehicle following control (ACC control). The preceding vehicle is the vehicle to be followed.

The ACC controller 4 controls the rotation speed and torque of an engine (not shown) by a throttle actuator 5, controls the transmission ratio of a stepped or continuously variable transmission by a transmission controller 6, and further controls a brake actuator 7 Controls the braking force.

The following vehicle determining device 8 comprises a CPU and its peripheral parts, and measures a distance l to an object ahead of the vehicle.
(t), the azimuth φ (t), the vehicle speed v (t), and the steering angle θ, the vehicle to be followed is determined. Following vehicle determination device 8
Is provided with a vehicle recognition unit 8a and a target vehicle selection unit 8b in the form of microcomputer software.

The vehicle recognizing unit 8a identifies the preceding vehicles ahead of the own vehicle based on the measured distance l (t), the own vehicle speed v (t), etc., calculates the relative speed with each preceding vehicle, and calculates the relative speed with each preceding vehicle based on the steering angle θ and the like. The traveling road shape is detected, and the traveling lane of each preceding vehicle is detected based on the detected direction φ (t). This allows
The preceding vehicle on the traveling lane of the own vehicle can be detected. The detection of the road shape may take into account road information of the current location from the navigation device. The target vehicle selection unit 8b determines the following vehicle based on the information on the preceding vehicle detected by the vehicle identification unit 8a.

The state notification device 9 displays the recognition state of the vehicle to be followed, the set inter-vehicle distance Ls, the set vehicle speed Vs, and the like. The state notification device 9 is installed in an instrument panel, for example, as shown in FIG. 2A, and as shown in FIG. 2B, a display portion 9a of a set vehicle speed Vs, a display portion 9b of a vehicle mark, a display portion 9c of a set inter-vehicle distance Ls, And preceding vehicle recognition state display section 9
d. The set vehicle speed display section 9a displays the set vehicle speed Vs set by the driver. The own vehicle mark display section 9b lights up during the ACC control.

The steering wheel has "far", "medium" and "close" operation buttons (not shown) for setting a set inter-vehicle distance Ls. Distance Ls according to own vehicle speed v (t)
Is set. The set inter-vehicle distance display section 9c illuminates three when the inter-vehicle distance Ls set by the driver is "far", illuminates two when it is "medium", and illuminates one when it is "near". .

Further, the preceding vehicle recognition state display section 9d is turned on when the lock-on control is being performed on the specific target vehicle to be followed. The state notification device 9 may be shared with a display of a navigation device (not shown), and the information may be displayed on the display of the navigation device. The driver may be notified by voice.

FIG. 3 is a flowchart showing the vehicle running control. The operation of the first embodiment will be described with reference to this flowchart. The ACC controller 4 and the following vehicle determination device 8 execute this control when the power of the vehicle traveling control device is turned on, and start the ACC control in step 1. In step 2, it is checked whether or not lock-on control for performing follow-up control for a specific vehicle is being performed. If lock-on control is being performed, the process proceeds to step 3, and if not, the process proceeds to step 6.

If the lock-on control is not underway, it is checked in step 6 whether a vehicle ahead of the own vehicle's traveling lane has been detected. If a preceding vehicle has been detected, the process proceeds to step 7; Proceed to.

Here, the method for detecting the preceding vehicle is based on the result of the measurement by the distance measuring device 1 and the road information of the current location from the navigation device. In order to prevent an object other than the vehicle such as a signboard in front of the vehicle from being erroneously recognized as a preceding vehicle, a predetermined time tS or more on the traveling lane of the own vehicle, that is, a predetermined number of times of measurement by the distance measuring device 1 When a vehicle is continuously detected as described above, it is determined that the vehicle is a preceding vehicle, and it may be determined that there is a preceding vehicle. When the determination time ts is used for qualifying the preceding vehicle, ACC control is temporarily performed for the determination time ts after the preceding vehicle is detected.

If the preceding vehicle is detected while the lock-on control is not being performed, the detected preceding vehicle is determined as a target to be followed in step 7 and lock-on control is started, and the preceding vehicle is set as the target vehicle (the target vehicle to be followed). Lock-on vehicle). Thereafter, the process proceeds to step 4. On the other hand, if the preceding vehicle has not been detected, it is determined in step 8 that there is no following vehicle, and the process proceeds to step 4.

In step 4, the ACC control routine shown in FIG. 4 is executed to perform ACC control. In step 11 of FIG. 4, the set vehicle speed Vs set by the driver is input. In the following step 12, the vehicle speed detecting device 2
To detect the vehicle speed v (t). In step 13, the target traveling speed of the host vehicle is determined based on the set vehicle speed Vs, the host vehicle speed v (t), the inter-vehicle distance to the target vehicle, and the relative speed to the target vehicle. Then, in step 14, the throttle actuator 5, the transmission controller 6, and the brake actuator 7 are controlled so that the vehicle speed becomes the target vehicle speed.

In the ACC control, when the lock-on control is being performed, the above-described follow-up control is performed with the lock-on vehicle as the target vehicle, and when the lock-on control is not being performed, the preceding vehicle on the own vehicle traveling lane is used as the target. The following control is performed as a vehicle. When there is neither a lock-on vehicle nor a preceding vehicle on the own vehicle traveling lane, a constant speed traveling control for traveling at a constant vehicle speed set in advance as no following vehicle is performed.

After executing the ACC control, the process returns to step 5 in FIG. 3 to check whether the ACC control is turned off. If the ACC control is turned off, the execution of the vehicle running control is terminated. Return and repeat the above process.

Next, if the lock-on control is already being performed in step 2, a follow-up target vehicle determination routine by lock-on processing shown in FIG. 5 is executed in step 3. In steps 21 to 22 in FIG. 5, the lock-on vehicle at the time of the previous measurement by the distance measurement device 1 (hereinafter, referred to as distance measurement) is tracked.

First, at step 21, the current position of the lock-on vehicle is predicted based on information such as the position, azimuth, and relative speed of the lock-on vehicle at the time of the previous distance measurement. The predicted current position of the lock-on vehicle is represented by (x, y) [m] as x [m] in the lateral direction from the own vehicle and y [m] forward from the own vehicle. The predicted current position (x, y) [m] is the position (Xo, Yo) [m] of the lock-on vehicle at the time of the last distance measurement and the relative speed (VXo, VYo) [m / s] with the lock-on vehicle. And the distance measurement time interval Δt [s] of the previous time and the current time.

X = Xo + VXo · Δt, y = Yo + VYo · Δt

Next, in step 22, areas of .DELTA.X and .DELTA.Y are set in the x and y directions centering on the predicted current position (x, y) of the lock-on vehicle, and detection is performed in the areas. To find out if there are any vehicles.

Since the tracking of the lock-on vehicle is performed based on the measurement data by the distance measuring device 1, the tracking range is naturally within the measuring range of the distance measuring device 1 (hereinafter referred to as the ranging range). Tracking is possible as long as there is a lock-on vehicle within the range. If a vehicle is detected in a predetermined area around the predicted current position of the lock-on vehicle predicted based on the previous distance measurement data, the vehicle is determined to be the same vehicle as the lock-on vehicle at the time of the previous distance measurement.

On the other hand, if no vehicle is detected in a predetermined area around the predicted current position, it is determined that the lock-on vehicle at the time of the previous distance measurement could not be tracked and was lost. Lock-on control is continued as long as the lock-on vehicle stays within the ranging range even if the lane changes, so losing the lock-on vehicle is when the lock-on vehicle goes out of the ranging range or when the vehicle locks with itself. It is conceivable that another vehicle interrupts the on-vehicle and measurement by the distance measuring device 1 becomes impossible.

When the lock-on vehicle changes lanes during the lock-on control, the follow-up control for following the lock-on vehicle while maintaining a constant inter-vehicle distance is continued. The lane change of the car depends on the driver's steering operation.

In step 23, the search result is confirmed, and if there is a detected vehicle in a predetermined area around the predicted current position (x, y) of the lock-on vehicle, the process proceeds to step 24, and the vehicle is locked on in the previous distance measurement. It is assumed that it is a vehicle. For example, FIG.
As shown in the figure, the lock-on vehicle 913 at the time of the previous distance measurement is out of the traveling lane of the own vehicle 911, and the own vehicle 91
Even when the preceding vehicle 912 exists in the traveling lane 1,
As long as the lock-on vehicle 913 at the time of the last distance measurement is tracked within the distance measurement range of the distance measuring device 1, the vehicle 913 is regarded as a lock-on vehicle. Then, the lock-on vehicle found in step 25 is set as the vehicle to be followed, and the process returns to step 4 in FIG. 3 to perform the above-described ACC control.

On the other hand, if there is no detected vehicle in a predetermined area around the predicted current position (x, y) of the lock-on vehicle at the time of the previous distance measurement, the lock-on vehicle at the time of the previous distance measurement is found this time at step 26. Judge that you could not. Then, in step 27, it is confirmed whether or not there is a vehicle ahead of the traveling lane of the own vehicle.

As described above, the method for detecting the preceding vehicle is based on the result of measurement by the distance measuring device 1 and the current road information from the navigation device. In order to prevent an object other than the vehicle such as a signboard in front of the vehicle from being erroneously recognized as a preceding vehicle, the vehicle may be located on the traveling lane of the own vehicle for a predetermined time tS or more, If a vehicle is detected continuously for more than the number of times of measurement, the vehicle may be determined to be a preceding vehicle, and a preceding vehicle may be present. When the determination time ts is used for qualifying the preceding vehicle, ACC control is temporarily performed for the determination time ts after the preceding vehicle is detected.

If a lock-on vehicle was not found during the previous distance measurement, but a preceding vehicle 912 was found on the traveling lane of the own vehicle 911 as shown in FIG. Is set as a new lock-on vehicle as a tracking target, and the process returns to step 4 in FIG. 3 to perform the ACC control described above.

As shown in FIG. 6c, if no lock-on vehicle was found at the time of the previous distance measurement and no preceding vehicle was found on the traveling lane of the own vehicle 911, there is no following vehicle in step 29. To release the lock-on control.

The result of the vehicle running control of the first embodiment will be described with reference to a situation as shown in FIG.
In FIG. 7A, when the vehicle A 922 ahead of the traveling lane of the own vehicle 921 is detected in the distance measurement range 920 of the distance measuring device 1, the preceding vehicle A 922 is determined to be a target to be followed, and lock-on control is started, and The vehicle A922 is a lock-on vehicle. From this state, even if the lock-on vehicle A922 changes lanes as shown in FIG. 7B, the lock-on vehicle A922 continues to be locked as long as the lock-on vehicle A922 is tracked within the distance measurement range 920. Treat as on vehicle.

However, as shown in FIG. 7C, when the lock-on vehicle A 922 deviates from a predetermined area around the predicted current position, a search is made for a vehicle ahead of the traveling lane of the own vehicle 921 in the distance measurement range 920. Own vehicle 9 in ranging area 920
When the preceding vehicle B 923 is detected in the traveling lane 21, the preceding vehicle B 923 is changed to a following target and set as a new lock-on vehicle. Then, lock-on vehicle B
When 923 moves in the direction of the outflow road and deviates from the distance measurement range 920, if no other preceding vehicle is detected in the distance measurement range 920, the lock-on control is canceled as there is no vehicle to be followed.

As described above, in the first embodiment, when the lock-on control is not being performed, if there is a vehicle ahead of the own vehicle in the travel lane within the range of the distance measurement, the lock-on control is performed with the vehicle as a tracking target. After that, the preceding vehicle is set as a lock-on vehicle. On the other hand, when the lock-on control is already being performed, the current position of the lock-on vehicle is determined with respect to the lock-on vehicle based on the position and relative speed at the time of the previous distance measurement and the distance measurement time interval between the previous time and the current time. Predict and search for a vehicle in a predetermined area centered on the predicted current position. If a vehicle is detected in a predetermined area around the predicted current position, the vehicle is identified as a lock-on vehicle and lock-on control is continued. If no vehicle is detected in the predetermined area around the predicted current position, the system detects a preceding vehicle in the traveling lane of the own vehicle, and if there is a preceding vehicle, determines it as a target to be followed and sets it as a new lock-on vehicle. I do. If no vehicle is detected in a predetermined area around the predicted current position and no preceding vehicle is detected on the traveling lane of the own vehicle, the lock-on control is released.

According to the first embodiment, the vehicle to be followed can be automatically specified, and the vehicle to be followed is manually specified by the input device during driving as in the conventional device. Complex operations can be eliminated.

According to the first embodiment, as shown in FIG. 8A or FIG.
When the tracking control is performed by locking on to the position No. 5, FIG.
b and as shown in FIG. 8d,
It is possible to prevent a situation in which the vehicle 904 running on the adjacent lane is mistakenly changed to the following target.

<Second Embodiment of the Invention> As shown in FIGS. 9A and 9B, when a preceding vehicle is detected on a curved road to determine an object to be followed, the vehicle 930 must be positioned on the traveling lane. Despite the preceding vehicle 932, the leading vehicle 931 in the next driving lane and the sign 934 around the road
In some cases, such a vehicle may be detected as a preceding vehicle, determined as a target to be followed, and lock-on control may be started. FIG. 9c
As shown in (1), even if the vehicle 936 is ahead of the traveling lane of the own vehicle 935, if the vehicle speed is low, the vehicle 936 may not be set as a tracking target.

In order to prevent such a situation, even if a preceding vehicle is detected and determined as a target to be followed, the lock-on control is not immediately started but the lock-on availability is determined in advance. An embodiment will be described.

FIG. 10 shows the configuration of the second embodiment.
The same components as those shown in FIG. 1 are denoted by the same reference numerals, and the description will focus on the differences. The lock-on availability determination unit 8c is formed by a software form of a microcomputer, and determines whether to lock on the preceding vehicle determined to be followed.

FIG. 11 is a flowchart showing vehicle running control. Steps that perform the same processing as in the flowchart shown in FIG. 3 are denoted by the same step numbers, and differences will be mainly described. In step 6, when the lock-on control is not being performed and the preceding vehicle is detected by the above-described method for detecting the preceding vehicle, the process proceeds to step 7A, and the detected preceding vehicle is determined as a target to be followed. . In the following step 7B, the lock-on determination routine shown in FIG. 12 is executed to determine whether or not to lock on the preceding vehicle determined to be the follow-up target.

In steps 31 to 32 of FIG. 12, the preceding vehicle on the own vehicle traveling lane at the time of the last distance measurement is tracked. First, in step 31, as described above, based on information such as the position and relative speed of the preceding vehicle on the own vehicle traveling lane detected at the previous distance measurement, the current value of the preceding vehicle detected at the previous distance measurement is determined. Predict the location. In the following step 32, it is confirmed whether or not the preceding vehicle on the own vehicle traveling lane detected at the time of the current distance measurement is present around the predicted current position. Specifically, it is checked whether or not the preceding vehicle detected this time is within a predetermined area centered on the predicted current position of the preceding vehicle at the time of the previous distance measurement.

When the preceding vehicle on the own vehicle traveling lane detected this time is around the predicted current position of the preceding vehicle on the previously detected own vehicle traveling lane, the process proceeds to step 33, and it is assumed that both vehicles are the same vehicle. Do not change the preceding vehicle. And
At step 34, the software timer T is incremented. In step 35, it is checked whether the software timer T has exceeded a predetermined time tD.

If the preceding vehicle follow-up control is continued for the same preceding vehicle for more than the predetermined time tD while the lock-on control is not being performed, the process proceeds to step 36, where the lock-on control is started to switch the preceding vehicle to the lock-on vehicle. Set to. afterwards,
In step 37, the timer T is reset, and the process proceeds to step 4 in FIG.
Perform control. On the other hand, the time measured by the timer T is a predetermined time t.
In the case of D or less, the process returns to the control program of FIG. 4 without starting the lock-on control.

When it is determined that the preceding vehicle on the own vehicle traveling lane detected this time is not around the predicted current position of the preceding vehicle on the previously detected own vehicle traveling lane, the process proceeds to step 38, and the previously detected preceding vehicle is detected. The preceding vehicle is changed to the preceding vehicle detected this time. Then, in a step 39, the timer T is reset, and the process returns to the control program of FIG.

Since the tracking of the preceding vehicle is performed based on the measurement data of the distance measuring device 1, the vehicle can be tracked within the distance measurement range of the distance measuring device 1. If the vehicle is a preceding vehicle on the lane and the previous preceding vehicle has changed lanes from the traveling lane of the own vehicle, it is no longer the preceding vehicle to be tracked at that time.

The result of the vehicle running control according to the second embodiment will be described with reference to the situation shown in FIG. 13 as an example. When the lock-on control is not being performed, the own vehicle 941 is located within the distance measurement range 940 of the distance measurement device 1 as shown in FIG.
If the vehicle 942 ahead of the traveling lane is detected,
For the time being, the preceding vehicle 942 is to be followed, but the vehicle is not immediately locked on to the preceding vehicle 942. If the preceding vehicle 942 has changed the driving lane as shown in FIG. 13B before the predetermined time tD has elapsed since the detection of the preceding vehicle 942, the vehicle preceding the driving lane of the own vehicle is searched for. If the vehicle B 943 ahead of the traveling lane is detected, the vehicle B 943 is set as a new preceding vehicle and is set as a follow-up target.

As shown in FIG. 13c, the same preceding vehicle B
If the preceding vehicle follow-up control is continued for more than the predetermined time tD with respect to 943, the lock-on control is started and the preceding vehicle B 943 is set as the lock-on vehicle. afterwards,
Even if the preceding vehicle B 943, which has already been locked on, changes lanes, it will be directly followed.

In the second embodiment, the continuation time of the preceding vehicle following control for the same preceding vehicle is a predetermined time t.
Until D, the preceding vehicle recognition state display section 9d of the above-mentioned state notification device 9 is made to blink, and when a predetermined time tD has elapsed and the vehicle is locked on, the preceding vehicle recognition state display section 9d is turned on. You may.

In step 6 in FIG. 11, in order to prevent an object other than the vehicle such as a signboard in front of the vehicle from being erroneously recognized as a preceding vehicle, a predetermined time t
When a vehicle is detected continuously for S or more, that is, for a predetermined number of times or more of the distance measurement device 1, it is recognized as a preceding vehicle,
When it is determined that there is a preceding vehicle, at least the determination time t of the preceding vehicle is included in the determination time tD when the lock-on vehicle is set.
Set a longer time than S.

As described above, according to the second embodiment,
If the vehicle ahead of the traveling lane of the own vehicle is not detected during the lock-on control and the vehicle is not immediately locked on, and the preceding vehicle following control for the same preceding vehicle is continued for a predetermined time tD or more. As long as the lock-on control is started with the preceding vehicle as the target to be followed and set as the lock-on vehicle, improperly fixed objects such as vehicles running on the next driving lane on a curved road and signboards beside the road This prevents the driver from locking on or locking on to a preceding vehicle whose vehicle speed is slow against the driver's will, so that an appropriate preceding vehicle can be locked on.

In the configuration of the above embodiment, the distance measuring device 1 is a measuring device, the steering angle detecting device 3 is a steering angle detecting device, and the following vehicle determining device 8 is a preceding vehicle detecting device and a vehicle specifying device. The controller 4 constitutes specific vehicle follow-up control means, constant speed traveling control means, and preceding vehicle follow-up control means, and the vehicle speed detection device 2 constitutes own vehicle speed detection means.

[Brief description of the drawings]

FIG. 1 is a diagram showing a configuration of a first embodiment.

FIG. 2 is a diagram showing a state notification device.

FIG. 3 is a flowchart showing vehicle traveling control.

FIG. 4 is a flowchart showing an ACC control routine.

FIG. 5 is a flowchart showing a routine for determining a vehicle to be followed by lock-on processing.

FIG. 6 is a diagram illustrating a method of changing a lock-on vehicle.

FIG. 7 is a diagram illustrating a result of a vehicle running control according to the first embodiment.

FIG. 8 is a diagram illustrating a result of vehicle travel control according to the first embodiment.

FIG. 9 is a diagram illustrating an operation when a preceding vehicle is found and lock-on control is started.

FIG. 10 is a diagram illustrating a configuration of a second embodiment.

FIG. 11 is a flowchart illustrating vehicle traveling control according to the second embodiment.

FIG. 12 is a flowchart illustrating a lock-on availability determination routine.

FIG. 13 is a diagram illustrating a result of vehicle travel control according to the second embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Distance measuring device 2 Vehicle speed detecting device 3 Steering angle detecting device 4 ACC controller 5 Throttle actuator 6 Transmission controller 7 Brake actuator 8 Following vehicle determining device 8a Vehicle recognizing unit 8b Target vehicle selecting unit 8c Lock-on availability determining unit 9 State notification apparatus

Continued on the front page F-term (reference) AA01 CC03 CC14 LL01 LL04 LL09 5H301 AA01 BB20 CC03 CC06 DD08 DD11 DD16 EE02 EE07 EE12 EE32 FF06 FF11 LL03 LL06 LL07 LL11 LL14 LL15 LL16 QQ06

Claims (4)

[Claims] 1. A measuring means for measuring an inter-vehicle distance and an azimuth to a vehicle ahead of the own vehicle, a steering angle detecting means for detecting a steering angle, and an autonomous vehicle based on the measured values of the inter-vehicle distance and azimuth and the detected steering angle. A preceding vehicle detecting means for detecting a preceding vehicle on the vehicle traveling lane; and setting a preceding vehicle as a specific vehicle if a preceding vehicle is detected on the own vehicle traveling lane when the specific vehicle to be followed is not set. A specific vehicle, and when the specific vehicle is set, tracks the specific vehicle based on the measurement result of the inter-vehicle distance and azimuth, and specifies the inter-vehicle distance while keeping the inter-vehicle distance constant as long as it is within the measurement range of the measuring means. Specific vehicle following control means for following the vehicle, own vehicle speed detecting means for detecting the own vehicle speed, and constant speed running when the specific vehicle is not set so that the own vehicle speed becomes a preset vehicle speed. Control means Vehicle travel control apparatus according to claim Rukoto. 2. The vehicle running control device according to claim 1, wherein the vehicle specifying means detects a preceding vehicle on the own vehicle running lane when the specific vehicle being tracked is lost. Is set to a new specific vehicle. 3. A measuring means for measuring an inter-vehicle distance and an azimuth to a vehicle ahead of the own vehicle, a steering angle detecting means for detecting a steering angle, and an autonomous vehicle based on the measured values of the inter-vehicle distance and azimuth and the detected steering angle. A preceding vehicle detecting means for detecting a preceding vehicle on the vehicle traveling lane; and a preceding vehicle following the preceding vehicle on the own vehicle traveling lane while maintaining a constant inter-vehicle distance when the preceding vehicle is detected on the own vehicle traveling lane. Follow-up control means, own-vehicle speed detecting means for detecting own-vehicle speed, and if no preceding vehicle is detected on the own-vehicle traveling lane,
A cruise control device for cruising at a constant speed such that the own vehicle speed becomes a preset vehicle speed. When the vehicle following control is performed, a vehicle specifying means for setting the preceding vehicle as a specific target vehicle to be followed, and when the specific vehicle is set, the specific vehicle is tracked based on the measurement result of the following distance and azimuth. And a specific vehicle follow-up control means for following a specific vehicle while keeping the inter-vehicle distance constant as long as the distance is within the measurement range of the measurement means. 4. The vehicle travel control device according to claim 3, wherein the vehicle identification unit predicts a current position of a preceding vehicle on the own vehicle travel lane based on a previous measurement result of the measurement unit. When a preceding vehicle is detected by the preceding vehicle detecting means around the predicted position at the time of the current measurement of the measuring means,
A vehicle travel control device that determines that the preceding vehicle at the time of the previous and the current measurement is the same.