JPH06191318A - Travel control device for vehicle - Google Patents

Abstract

PURPOSE:To continue smooth follow-up travel even after an inter-vehicle distance from a preceding vehicle is increased suddenly and a self-vehicle is accelerated by the operation of an adjusting lever in a vehicle travel control device which travels the vehicle following up the preceding vehicle while maintaining the inter-vehicle distance from the preceding vehicle at a safety inter-vehicle distance. CONSTITUTION:Based on signals from an inter-vehicle distance sensor 10 and a vehicle speed sensor 12, a micro-computer 18 calculates a target inter-vehicle distance and controls a throttle actuator 20 to run a vehicle following a preceding vehicle. When an adjusting lever 14 completes its operation after an adjusting lever 14 is operated by a driver to accelerate a self-vehicle, and when a relative speed is below a specified limit, an inter-vehicle distance at completion of operation is set as a target inter-vehicle distance and, when it is over a specified limit, a target inter-vehicle distance before the adjusting lever 14 is operated is re-set as a target inter-vehicle distance.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicular travel control device, and more particularly to an improved vehicular travel control device for performing follow-up travel in accordance with a driver's intention.

[0002]

2. Description of the Related Art Conventionally, a traveling 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.

Here, even when the vehicle is traveling at a constant speed at a vehicle speed set by the driver himself, there are cases where it is desired to change the set vehicle speed depending on the surrounding environment. Depending on the vehicle type, the current inter-vehicle distance may be too short or too long, and there may be a case where it is desired to change the inter-vehicle distance. Also, if the preceding vehicle changes lanes and the radar that captures the preceding vehicle catches a vehicle further ahead or if the preceding vehicle suddenly accelerates, the preceding vehicle is lost on the curved road, and then the preceding vehicle is again detected. There may be a case where it is desired to adjust the inter-vehicle distance when the inter-vehicle distance with the preceding vehicle becomes large, such as when it is captured. Therefore,
In order to adjust such set vehicle speed and inter-vehicle distance by the driver's hand operation, an adjustment switch or lever is provided in the driver's seat, and the driver operates the adjustment switch / lever to set the set vehicle speed or inter-vehicle distance. A configuration that can be changed is proposed. The applicant of the present application also filed Japanese Patent Application No. 3-
No. 299199 proposes a vehicle travel control device having such an adjusting lever.

[0005]

When adjusting the inter-vehicle distance with such a manually operable adjustment lever, the inter-vehicle distance with the preceding vehicle at the end of the manual operation is set as a new target inter-vehicle distance. , For example, when the preceding vehicle changes lanes as described above and the radar that captures the preceding vehicle catches the vehicle ahead, operate the adjustment lever to reduce the inter-vehicle distance to the original inter-vehicle distance. When accelerating the host vehicle, the speed difference from the preceding vehicle increases, so the driver stops operating the adjustment lever when the vehicle distance reaches a little longer than the desired vehicle distance, and It is common to expect to get closer to the target distance. Therefore, in this case, the follow-up traveling is newly started at a longer inter-vehicle distance at the end of the manual operation, which causes a problem that the inter-vehicle distance desired by the driver cannot be controlled.

The present invention has been made in view of the above-mentioned problems of the prior art, and an object thereof is to perform follow-up running at a vehicle-to-vehicle distance desired by a driver even after operating an adjusting means such as a manually operable adjusting lever. An object of the present invention is to provide a vehicle travel control device that can continue.

[0007]

In order to achieve the above object, a vehicle travel control device of the present invention comprises an inter-vehicle distance detecting means for detecting an inter-vehicle distance to a preceding vehicle, and a vehicle speed for detecting the speed of the own vehicle. The detecting means, the relative speed detecting means for detecting the relative speed between the preceding vehicle and the own vehicle, the target inter-vehicle distance calculating means for calculating the target inter-vehicle distance as a function of the speed of the own vehicle, and the inter-vehicle distance with the preceding vehicle are In a vehicle control device including a control unit that controls a throttle to obtain a target inter-vehicle distance, a manually operable adjusting unit that increases or decreases the speed of the host vehicle, and a relative speed at the end of the manual operation of the adjusting unit. When the magnitude is equal to or greater than a predetermined value, it is set to the target inter-vehicle distance before starting the manual operation, and when the magnitude of the relative speed is less than the predetermined value, the inter-vehicle distance at the end of the manual operation is set to the target inter-vehicle distance. Target inter-vehicle distance adjustment And having a stage.

[0008]

The vehicle travel control device of the present invention has such a structure and adjusts the target inter-vehicle distance by the relative speed of the preceding vehicle at the end of the manual operation of the manually operable adjusting means. Is. That is, it is when the speed difference between the preceding vehicle and the own vehicle is large, that is, when the relative speed is large that the driver finishes the manual operation of the adjusting means before the desired inter-vehicle distance is reached. When the speeds are almost the same, the driver finishes the manual operation of the adjusting means in the vicinity of the desired inter-vehicle distance.

Therefore, in the present invention, when the relative speed at the end of the manual operation of the adjusting means is a predetermined value or more,
The target inter-vehicle distance before the operation of the adjusting means is adjusted, and when the relative speed is equal to or less than the predetermined value, the inter-vehicle distance at the end of the manual operation is set as the target inter-vehicle distance, so that the inter-vehicle distance desired by the driver is automatically set. To do.

[0010]

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. Inter-vehicle distance sensor 10 as inter-vehicle distance detecting means
Is provided at the front of the vehicle. This inter-vehicle distance sensor 10
For example, it is possible to use a CCD camera, a radar device, a laser radar device, or the like that captures the image of the 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, an adjusting lever 14 for setting the vehicle speed during constant speed traveling and for increasing / decreasing the speed of the own vehicle during following traveling is provided in the driver's seat, and a system switch 16 is similarly provided in the driver's seat. The signals from these sensors and switches are supplied to the microcomputer 18.

The microcomputer 18 is provided 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. In this embodiment, the vehicle speed is controlled by sending a control signal to the actuator 22 (basically, the brake actuator is not controlled because the vehicle speed control is basically performed by the throttle control, but the brake control can be performed if necessary). To control
The alarm / display device 24 provided in the driver's seat appropriately displays the current inter-vehicle distance, or gives an alarm to the driver when the inter-vehicle distance becomes unacceptable.

When the follow-up running is started by the switch 16, the microcomputer 18 calculates the target inter-vehicle distance LT based on the vehicle speed signal from the vehicle speed sensor 12. Then, the control amount is calculated based on the difference between the current inter-vehicle distance detected by the inter-vehicle distance sensor 10 and the calculated target inter-vehicle distance, and the throttle actuator 20 is controlled to follow the preceding vehicle.

Here, for example, when the preceding vehicle changes lanes and the vehicle ahead is captured by the vehicle distance sensor 10, the vehicle distance increases discontinuously. At this time, the microcomputer 18 outputs an acceleration command to the throttle actuator 20, but the acceleration command cannot provide sufficient acceleration desired by the driver. Therefore, the driver manually operates the adjustment lever 14 to accelerate the own vehicle, and the inter-vehicle distance with the new preceding vehicle is the desired inter-vehicle distance, that is, the target inter-vehicle distance before the preceding vehicle that has been following last time before changing lanes. Then try to follow this new preceding vehicle.

However, when the host vehicle accelerates and approaches this new preceding vehicle, the driver finishes operating the adjusting lever 14 before the desired inter-vehicle distance is reached, and thereafter the desired inter-vehicle distance is reached by coasting. Try to set. Therefore,
If the inter-vehicle distance at the end of the manual operation of the adjusting lever 14 is set to the target inter-vehicle distance, the target inter-vehicle distance becomes larger than the inter-vehicle distance desired by the driver.

Therefore, in this embodiment, the relative speed obtained by differentiating the inter-vehicle distance detected by the inter-vehicle distance sensor 10 is compared with a predetermined value stored in advance in a ROM or the like, and the target is determined according to the result. Adjust the inter-vehicle distance appropriately.

FIG. 2 shows the change with time in the distance from the preceding vehicle from when the driver manually operates the adjusting lever 14 until the distance between the preceding vehicle and the preceding vehicle discontinuously increases. ing. In the figure, the horizontal axis represents time and the vertical axis represents the inter-vehicle distance from the preceding vehicle. The target inter-vehicle distance when there is no change in the preceding vehicle and the vehicle is following the preceding vehicle is L in the figure.
It is represented by T ₁ . When the preceding vehicle changes lanes or the preceding vehicle suddenly accelerates and the inter-vehicle distance rapidly increases, the driver operates the adjusting lever 14 ((A) in the figure). Then, the own vehicle accelerates, and the inter-vehicle distance from the preceding vehicle gradually decreases. When the driver finishes operating the adjusting lever 14 is (a) in the figure, that is, when the relative speed with the preceding vehicle (corresponding to the slope of the distance change in the figure) is small, Since it can be determined that the driver desires the inter-vehicle distance, the inter-vehicle distance LT ₂ at this time is set as the target inter-vehicle distance. On the other hand, when the driver finishes the operation of the adjusting lever 14 in (c) in the figure,
That is, when the relative speed with respect to the preceding vehicle is high, the inter-vehicle distance desired by the driver has not yet been reached, but the driver expects that the desired inter-vehicle distance will be reached by inertial running of the vehicle. It is possible to determine that the lever 14 has been operated. In this case, the inter-vehicle distance LT ₃ at that time should not be set as the target inter-vehicle distance, and the target when the preceding vehicle is following following the lane change. The inter-vehicle distance LT ₁ is set as the target inter-vehicle distance. As a result, even after the operation of the adjusting lever 14 is completed, the target inter-vehicle distance LT ₁ or LT
_In either case ₂ , the follow-up running desired by the driver can be continued.

The processing of the microcomputer 18 will be described in more detail below with reference to the processing flowchart of FIG.

The system switch 16 is turned on, and it is determined whether or not the operation of the adjusting lever 14 is started while the follow-up traveling is being performed (S100). When the operation of the adjusting lever 14 is started, the target inter-vehicle distance LT at this time
₁ is input to the target inter-vehicle distance variable LT and stored in the memory (S110). When the adjusting lever 14 is operated, as described above, the host vehicle accelerates according to the operation amount of the adjusting lever, and the inter-vehicle distance from the preceding vehicle is shortened. Then, when the operation of the adjusting lever 14 is completed at a certain point (S12
0), the inter-vehicle distance LT ₂ at this time is input to the inter-vehicle distance variable DIS (S130). Further, the relative speed VRR ₂ obtained by differentiating the inter-vehicle distance at this time with respect to the relative speed variable V
Input to RR and store in memory (S140).

Next, the relative speed VRR ₂ at the end of the operation of the adjusting lever 14 is compared with a predetermined relative speed value VRR ₀ stored in the ROM in advance (S150) to determine V.
When the magnitude of RR ₂ is less than or equal to the predetermined value VRR ₀ , that is, when the operation of the adjusting lever 14 is completed while the preceding vehicle and the own vehicle are traveling at substantially the same speed, the inter-vehicle distance L
Setting the T ₂ as a new target inter-vehicle distance (S16
0). On the other hand, when the relative speed VRR ₂ is equal to or greater than the predetermined value VRR ₀ , the target inter-vehicle distance desired by the driver is not the target inter-vehicle distance at this time but LT ₁ and the target inter-vehicle distance is determined from the memory. It is read and reset to LT ₁ (S170). In this way, the target inter-vehicle distance LT is LT
It is reset to ₁ or LT ₂ and the follow-up running continues again. At this time, when the relative speed with respect to the preceding vehicle is small, the follow-up traveling is continued at the target inter-vehicle distance LT ₂ , and when the relative speed with the preceding vehicle is large, the following distance is LT ₁ with respect to the preceding vehicle.
After that, the following traveling is continued at the target inter-vehicle distance LT ₁ . Therefore, even after the operation of the adjusting lever 14, the follow-up running contrary to the driver's intention is not performed, and the smooth follow-up running can be continued even after the operation of the adjusting lever 14.

[0022]

As described above, according to the vehicle travel control device of the present invention, the driver's desired follow-up travel can be smoothly continued even after the operation of the adjusting means such as the adjusting lever is completed. You can

[Brief description of drawings]

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

FIG. 2 is an explanatory view of the principle of setting the target inter-vehicle distance after the adjustment lever operation of the embodiment.

FIG. 3 is a processing flowchart of the microcomputer of the embodiment.

[Explanation of symbols]

 10 Vehicle Distance Sensor 12 Vehicle Speed Sensor 14 Adjustment Lever 16 System Switch 18 Microcomputer 20 Throttle Actuator 22 Brake Actuator 24 Alarm / Display Device

Claims (1)

[Claims] 1. An inter-vehicle distance detecting means for detecting an inter-vehicle distance from a preceding vehicle, a vehicle speed detecting means for detecting a speed of the own vehicle, and a relative speed detecting means for detecting a relative speed between the preceding vehicle and the own vehicle. A vehicle control device comprising: a target inter-vehicle distance calculating means for calculating a target inter-vehicle distance as a function of the speed of the host vehicle; and a control means for controlling a throttle so that the inter-vehicle distance with a preceding vehicle becomes the target inter-vehicle distance. Adjusting means for increasing or decreasing the speed of the own vehicle, and if the relative speed at the end of the manual operation of the adjusting means is equal to or more than a predetermined value, the target inter-vehicle distance before starting the manual operation is set. A vehicle traveling control device comprising: a target inter-vehicle distance adjusting unit that sets the inter-vehicle distance at the end of the manual operation to the target inter-vehicle distance when the magnitude of the relative speed is equal to or less than a predetermined value.