JP2001001790A - Vehicle running control system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To perform running control appropriately even when a detected portion has changed by changing contents to be controlled by control means when it is judged that a portion detected by judgement means is inappropriate. SOLUTION: A relative speed Vra with respect to a preceding vehicle is set based on a received judgement signal indicating that a detected portion on the preceding vehicle is inappropriate (S24). In an ECU for controlling a following distance, a target acceleration and deceleration speed Ata is calculated based on the relative speed and sent to an engine ECU (S25). In the engine ECU then, an opening of an electronic throttle is adjusted based on the target acceleration and deceleration speed that is received (S26). In this way, calculated relative value is corrected when a detected portion of a preceding vehicle sensed by a laser radar device has changed. Therefore, comfortable running can be achieved without unnecessary decelerating.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle traveling control device for detecting a relative relationship with a preceding vehicle and controlling the acceleration and deceleration of the own vehicle based on the detection result.

[0002]

2. Description of the Related Art Conventionally, there has been known a vehicle traveling control device that detects a preceding vehicle and controls acceleration / deceleration of the own vehicle based on the detected situation of the preceding vehicle. In such an apparatus, a relative speed with respect to a preceding vehicle and an inter-vehicle distance are detected by, for example, a laser radar that sweeps a laser to a predetermined range ahead. Then, a target inter-vehicle distance is set based on the detected relative distance, and the accelerator opening and the like are controlled so that the inter-vehicle distance approaches the target inter-vehicle distance.

[0003] As a result, the distance between the vehicle and the preceding vehicle can be automatically maintained at an appropriate value, and the burden on the driver can be reduced.

[0004]

Here, various studies have been made on such an apparatus. As a result, when trying to follow a high-speed vehicle by changing lanes, a sufficient speed may not be obtained in some cases. Was. This is considered to be due to the following reasons.

First, the detection of a preceding vehicle by the radar is basically based on detecting the rear part of the preceding vehicle. On the other hand, on a road having a plurality of lanes, a side portion of a preceding vehicle in another lane is often detected. Therefore, when changing lanes, the state changes from a state in which the side of the preceding vehicle in the adjacent lane is detected to a state in which the rear part is detected. Then, it is conceivable that the relative speed is recognized as an erroneous value in accordance with the change of the detection site.

SUMMARY OF THE INVENTION The present invention has been made in consideration of the above problems, and has as its object to provide a vehicle traveling control device capable of performing appropriate traveling control even when a detected portion changes.

[0007]

SUMMARY OF THE INVENTION The present invention provides a detecting means for detecting a relative relationship between a preceding vehicle and a host vehicle, a control means for controlling a speed of the host vehicle based on the detected relative relationship, Determining means for determining whether the part of the preceding vehicle detected by the detecting means is appropriate; and control change for changing the control content of the control means when the part detected by the determining means is determined to be inappropriate. Means.

[0008] When the detected part of the preceding vehicle is not appropriate, by changing the control content, inappropriate control can be corrected and the driving control can be performed without feeling uncomfortable for the driver. The relative relationship includes, for example, an inter-vehicle distance, a relative speed, a relative acceleration, and the like.

It is preferable that the control change means changes the control content of the control means by correcting the detected relative relationship. For example, by correcting the relative relationship, the control content based on this is automatically changed.

It is preferable that the control change means changes the content of control by the control means by changing the detected relative relationship to a preset value within a predetermined time. For example, the deceleration can be prevented by setting the relative speed to 0, and the acceleration can be performed by setting the value to + (the direction of moving away).

Preferably, the control changing means changes the control by the control means so as to maintain the speed of the vehicle at a predetermined value within a predetermined time. For example, by maintaining the current vehicle speed, unnecessary deceleration can be prevented.

It is preferable that the determining means determines that the preceding vehicle is not appropriate when the detected part of the preceding vehicle changes. For example, by determining that it is not appropriate when the part to be detected changes from the vehicle side to the vehicle rear,
Erroneous control based on a change in the recognized vehicle position can be prevented.

Further, the detecting means obtains scan data by scanning a laser in a predetermined range in front, and the judging means determines a detected part of the preceding vehicle based on the obtained scan data. It is preferable to determine whether or not. By such laser scanning, for example, a side portion, a rear portion, and the like of a preceding vehicle can be suitably detected.

[0014] It is preferable that the determination means determines that the preceding vehicle is not appropriate when the detected location of the preceding vehicle changes from the side to the rear of the vehicle.

[0015]

Embodiments of the present invention (hereinafter referred to as embodiments) will be described below with reference to the drawings.

FIG. 1 is a block diagram showing the overall configuration of the vehicle traveling control device according to the embodiment. The laser radar device 10 is attached to, for example, a bumper of a vehicle, irradiates a laser beam toward the front of the vehicle, and receives reflected light from a preceding vehicle.

For example, a laser diode is pulse-driven, and a pulse laser beam is output from the laser diode. Then, the pulse laser light is repeatedly scanned in a predetermined range (left and right directions) in front of the vehicle by a rotating polygon mirror. The pulse laser light is also scanned in the vertical direction by making the inclination angles of the respective surfaces of the polygon mirror different.

On the other hand, the pulse laser light reflected by the preceding vehicle is received by a photodiode and converted into an electric signal. Then, the time from the output of the pulse laser light to the reception of the reflected light is measured, and the inter-vehicle distance to the preceding vehicle is measured. Further, the relative speed is measured from the temporal change of the inter-vehicle distance. The laser radar device 10 also detects information on the preceding vehicle, such as the positional relationship of the preceding vehicle.

The configuration of the laser radar device 10 is disclosed in Japanese Patent Application Laid-Open No. H11-42956. Further, instead of the laser radar device 10, another type of radar such as a millimeter wave radar can be used. Also, the relative velocity can be measured by detecting a Doppler shift in the transmitted and received waves.

Information such as the inter-vehicle distance and the relative speed measured by the laser radar device 10 is supplied to the inter-vehicle control ECU 12. The inter-vehicle control ECU 12 calculates the relative speed supplied from the laser radar device 10, the inter-vehicle distance, and the like.
A target inter-vehicle distance is set, and the detected inter-vehicle distance is compared with the target inter-vehicle distance to generate an instruction such as a target acceleration / deceleration, a shift down request, a brake request, and the like. It should be noted that vehicle information detected by other sensors such as the current vehicle speed can be considered, and further, relative acceleration and the like can be considered.

Instructions such as a target acceleration / deceleration, a shift down request, a brake request, and the like from the inter-vehicle control ECU 12 are supplied to the engine ECU 14. A VSC ECU 22 that controls the electronic throttle 16, the shift control unit 18, the brake actuator 20, and the like is connected to the engine ECU 14, and the engine ECU 14 controls these. The electronic throttle 16 is for electronically controlling the throttle opening, and by controlling this, the acceleration / deceleration of the vehicle is adjusted to match the target acceleration / deceleration. The shift control unit 18 performs a downshift in response to a downshift request. Further, the VSC ECU 22 controls the brake actuator 20 to decelerate the vehicle according to the brake request.

In this example, vehicle information such as the vehicle speed is supplied to the inter-vehicle control ECU 12 via the engine ECU 14. The engine ECU 14 also performs fuel injection control and the like, and the VSC ECU 22 also performs other controls for stable running of the vehicle, but these are not described here.

In the apparatus according to the present embodiment, the laser radar apparatus 10 detects whether or not the detected target portion of the preceding vehicle has changed from the side to the rear. The processing in the laser radar device 10 will be described with reference to FIG.

First, scan data obtained by scanning the laser forward is captured (S11). Next, the acquired scan data is grouped by distance and angle (S
12). Thereby, the scan data is grouped for each vehicle. Then, a relative speed is calculated for each grouped data to determine a moving object (S13). That is, if the relative speed is substantially the same as the own vehicle speed, this is a stationary object, and it is determined whether or not it is a moving object based on the relative speed.

After determining the moving object as described above, it is determined whether or not the front and rear length of the moving object is equal to or greater than a preset value α (S14). Here, normally, when following the preceding vehicle, since the rear part of the vehicle is detected, the front-rear length is detected to be considerably short. The length is detected to be considerably long and is equal to or more than α.

If the determination in S14 is YES, and the change rate of the relative speed has become equal to or greater than a preset value β within a predetermined time Ta (S15) (S1).
6) Recognize that the detected part of the preceding vehicle has changed, and determine that the detected part is inappropriate (S17). This is because when the state changes from detecting only the side part of the preceding vehicle to detecting the rear part as well, the relative speed of the own vehicle to the preceding vehicle increases, and the rate of change of the relative speed becomes It uses that it is more than β. Generally, even if the relative speed changes while the rear portion of the vehicle is continuously detected, the change rate is less than β.

Then, in S18, information on the preceding vehicle including the determination result in S17 is transmitted to the following distance control ECU 12. If the determination in S14 or S15 is NO, the process proceeds to S17 to transmit information. The information to be transmitted includes an inter-vehicle distance to a preceding vehicle, a relative speed, and the like.

Here, the detection of the preceding vehicle in S14 and S15 will be described with reference to FIGS. First, let us consider a case in which the vehicle overtakes the own vehicle in the overtaking lane on the right side of a vehicle having a high vehicle speed and follows the overtaking vehicle. In this case, since the nose of the own vehicle is directed to the right side in order to change lanes, the preceding vehicle that is about to follow the next lane enters the radar field of view and the side of the preceding vehicle is detected. In the figure, the detection points where the pulse laser is reflected are shown, and the grouped detection points are recognized as the preceding vehicle. When the side portion is detected in this manner, the difference in the relative distance (front and rear length) between the grouped detection points is large, and the result in S14 is YES. Further, the center of gravity of the grouped detection points is determined to be the preceding vehicle position.

Then, within a predetermined time Ta, the relative positional relationship changes, and the preceding vehicle can be detected not only at the side but also at the rear. Then, the detection points become the side portion and the rear portion, forming an L-shaped group. When the center of gravity of these detection points is taken, the position of the center of gravity moves from the center position of the preceding vehicle to the rear position. Therefore, the relative speed of the own vehicle with respect to the preceding vehicle greatly changes based on the changed position of the center of gravity.
In S15, it is conceivable that the magnitude of the change is determined based on the difference in the relative speed, not the rate of change, and whether the relative speed exceeds a predetermined value, not the difference in the relative speed. May be.

As described above, in the laser radar device 10, when it is determined that the detected portion of the preceding vehicle is inappropriate (S21), the laser radar device 10 transmits to the inter-vehicle control ECU 12 a determination signal regarding a change in the detected portion. Is transmitted (S22), and the following distance control ECU 12 receives this determination signal (S23).

Then, based on the reception of the determination signal,
The relative speed with respect to the preceding vehicle is set as Vra (S24). The relative speed Vra is for compensating for a change in the relative speed according to the change in the detection site as described above, and may retain the previous value, or may be a preset value. Further, a value obtained by compensating the position of the center of gravity on the vehicle from the positional relationship of the spots whose center of gravity is obtained may be used.

The inter-vehicle control ECU 12 calculates a target acceleration / deceleration Ata based on the relative speed, and transmits the calculated target acceleration / deceleration Ata to the engine ECU 14 (S25). In the case of NO in S21, the correction of the relative distance as described above is not necessary, and the flow shifts to S25.

Then, the engine ECU 14 adjusts the opening of the electronic throttle 16 based on the supplied target acceleration / deceleration (S26). As described above, according to the present embodiment, when the detected part of the preceding vehicle in the laser radar device 10 changes, the calculated relative speed is corrected. Accordingly, unnecessary deceleration can be prevented, and the vehicle can travel without feeling uncomfortable.

Here, if Vra is set to 0 or more,
Braking and downshifting can be prevented from being performed.
Further, if the value is set to a value of +, it is possible to control the degree of acceleration, so that it is possible to perform the following control without a sense of incongruity for the driver.

Instead of making the relative speed equal to or higher than 0 as described above, the brake control and the downshift control can be temporarily or prohibited for a certain period of time. As a result, although deceleration due to throttle closing occurs, large deceleration can be prevented. Further, the current vehicle speed may be maintained temporarily or for a fixed time.

[0036]

As described above, according to the present invention,
If the detected part of the preceding vehicle is not appropriate, the control content is changed. For example, when the detected part of the preceding vehicle shifts from the side to the rear at the time of lane change, the part recognized as the position of the preceding vehicle moves rearward. Therefore, the relative speed of the preceding vehicle is recognized as lower than the actual speed (negative side). In the present invention, in such a case, the control is corrected,
Unnecessary deceleration can be prevented, so that when the lane is changed, cruise control without discomfort to the driver can be performed.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating an overall configuration of a device according to an embodiment.

FIG. 2 is a flowchart showing an operation for detecting that a detected part is an inappropriate part.

FIG. 3 is a diagram illustrating detection of an inappropriate part.

FIG. 4 is a flowchart showing an operation in the case of inappropriate part detection.

[Explanation of symbols]

10 Laser radar device, 12 Vehicle control ECU, 14
Engine ECU, 16 electronic throttle, 18 shift control unit, 20 brake actuator, 22 VS
CECU.

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Akira Hattori 1 Toyota Town, Toyota City, Aichi Prefecture Inside Toyota Motor Corporation (72) Inventor Tsuneo Miyakoshi 1 Toyota Town, Toyota City, Aichi Prefecture Toyota Motor Corporation F Term (reference) 3D044 AA41 AA45 AB01 AC26 AC55 AC59 AD04 AD17 AD21 AE14 3G093 AA01 BA02 BA23 CB04 CB10 DB05 DB16 DB18 DB21 EA09 EB03 EB04 EC02 FA04 5H180 AA01 CC03 CC14 LL01 LL02 LL04 LL09 5J070 AC02

Claims (7)

[Claims] A detecting means for detecting a relative relationship between the preceding vehicle and the own vehicle; a controlling means for controlling a speed of the own vehicle based on the detected relative relationship; and a preceding vehicle detected by the detecting means. Determination means for determining whether or not the part is appropriate, and control change means for changing the control content of the control means when the part detected by the determination means is determined to be inappropriate. Vehicle travel control device. 2. The vehicle travel control device according to claim 1, wherein the control change unit changes the control content of the control unit by correcting the detected relative relationship. 3. The apparatus according to claim 2, wherein the control change unit changes the control content of the control unit by changing a detected relative relationship to a preset value within a predetermined time. A vehicle travel control device characterized by the above-mentioned. 4. The apparatus according to claim 1, wherein the control change unit changes the control by the control unit so as to maintain the speed of the vehicle at a predetermined value within a predetermined time. Vehicle travel control device. 5. The vehicle travel control according to claim 1, wherein the determining unit determines that the detected preceding vehicle is not appropriate when a detected part of the preceding vehicle changes. apparatus. 6. The apparatus according to claim 1, wherein said detection means scans a laser in a predetermined range in front to obtain scan data, and said determination means obtains scan data. A vehicle travel control device that determines whether a detected part of a preceding vehicle is appropriate based on data. 7. The apparatus according to claim 1, wherein the determination unit determines that the preceding vehicle is not appropriate when the detected location of the preceding vehicle changes from the side to the rear of the vehicle. A vehicle travel control device characterized by the above-mentioned.