JP3401855B2 - Car driving control device - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a travel control device for an automobile which maintains a safe distance between the preceding vehicle and the own vehicle. According to the present invention, a stop lamp is turned on when power is applied. [0002] The cause of a rear-end collision on a highway or the like is as follows.
Drivers who fall asleep or drunk driving account for the majority.
Under such circumstances, an inter-vehicle distance warning system has been developed which detects the inter-vehicle distance between the own vehicle and the preceding vehicle and issues an alarm to the driver when the distance becomes less than a certain distance. I have. The outline of the conventional system of this system is to measure the inter-vehicle distance between the own vehicle and the preceding vehicle using a laser beam or a stereo vision camera, etc., and to generate an alarm in the vehicle when the inter-vehicle distance becomes less than the safe inter-vehicle distance. Has become. [0003] When an alarm is generated as described above, the driver depresses the brake to decelerate the vehicle and performs an operation of increasing the inter-vehicle distance to a predetermined distance or more. In a vehicle equipped with a vehicle transmission, as disclosed in Japanese Patent Publication No. Hei 2-24685, the vehicle transmission is automatically downshifted (overdrive off) to assist the driver in decelerating. There has been proposed a technique for applying an engine brake. [0004] However, in the high-speed range,
High deceleration even when downshifting from overdrive,
Nevertheless, since the stop lamp does not light up, there is a problem that the following vehicle cannot be informed that the own vehicle is decelerating. Further, in order to maintain the distance between vehicles, Japanese Patent Laid-Open No.
The same can occur when the brake is automatically driven as disclosed in Japanese Patent Application No. 0-91500. In order to solve the above problems, according to the present invention, the vehicle is controlled by the braking means based on the distance between the vehicle and the preceding vehicle or the relative speed between the vehicle and the preceding vehicle. the traveling control device for a motor vehicle which is adapted apply power, equipped with a stop lamp lighting means estimating deceleration by Ri is estimated braking force of the brake means to light the stop lamp If so becomes a predetermined value or more Things. [0007] [action] In the travel control device, the inter-vehicle distance, but the braking means based on the relative velocity Ru braking force is applied <br/> is on the vehicle are actuated, the estimated deceleration which is estimated by the braking force Becomes greater than or equal to a predetermined value, the stop lamp is turned on.
Therefore, it is possible to notify the following vehicle that the own vehicle is in a deceleration state. An embodiment of the present invention will now be described with reference to the accompanying drawings. FIG. 1 shows an automobile provided with an automobile traveling control device. In the figure, 1 is a stereoscopic camera, 2 is a laser radar, 3 is a throttle actuator, 4 is a brake actuator, 5 is an operation switch / information display section, 6 is a controller, and 7 is a vehicle speed sensor. Reference numeral 8 denotes an engine, and 9 denotes an automatic transmission (hereinafter referred to as A / T). Also, 7a
Is a handle angle sensor, 22 is a brake pedal, 2
5 is an accelerator pedal, 7b is a brake switch, 7c
Is a brake pedal switch, and 7d is an accelerator pedal switch. The stereo vision camera 1 has two CCD cameras 11 and 12 for photographing a scene in front of a car placed side by side. The distance to an object visually recognized by the left and right cameras 11 and 12 is determined by the left and right. The distance between the optical axes of the cameras 11 and 12, the focal length of the lens, and the C of the cameras 11 and 12
It is obtained from the amount of displacement of the image on the CD. [0010] The images captured by the two cameras 11 and 12 are subjected to image processing by the image processing unit of the controller 6 to perform the following recognition. Recognition of the preceding car (preceding car). Recognition of a white line that indicates the lane on which the vehicle is traveling, among a plurality of lanes (lanes) on a highway. Recognition of the inter-vehicle distance between the preceding vehicle and the own vehicle. The above-mentioned recognition of the preceding vehicle is performed, for example, as follows. That is, an area surrounded by a vertical straight line is extracted from the image, and an image which is symmetrical in the extracted area and whose position does not move much in the image that is successively captured is recognized as a preceding vehicle. I do. The recognition of the white line indicating the traveling lane of the host vehicle is performed, for example, as follows. That is, as shown in FIG. 5A, the front road screen is fetched from the stereoscopic camera 1 and then, as shown in FIG.
The brightness of the pixels is checked along the lines W1 to W4, and a bright point is selected as a white line candidate, as shown in FIG. 5 (c).
A line segment obtained by interpolating the upper candidate point and the lower candidate point is extracted as a white line. Recognition of the inter-vehicle distance between the preceding vehicle and the host vehicle is performed as follows. That is, from the two cameras 11 and 12 of the stereoscopic camera 1, FIG.
Two images are obtained as shown in FIG. The same image as the car image surrounded by the window on the right image is slightly shifted in the left image. Therefore, the position of the most matching image is obtained while shifting the right-side automobile image surrounded by the window by one pixel in the search area of the left-side image. At this time, as shown in FIG.
The focal length of the lenses 1 and 12 is f, and the left and right cameras 11 and 1
2, the distance between the optical axes is L, the pixel pitch of the CCD is P,
In FIGS. 6A and 6B, assuming that the number of pixels obtained by shifting the right image until the left and right vehicle images match is n, the distance R to the preceding vehicle (inter-vehicle distance) R is calculated according to the principle of triangulation. Can be calculated by the following equation. R = (f · L) / (n · P) On the other hand, one laser radar 2 is disposed at each of the right front end and the left front end of the vehicle. The spread angle of the laser beam emitted from the laser radar 2 is 2 degrees. By measuring the time from when the laser beam is emitted from the laser radar 2 to when the laser beam reflected by the object returns to the laser radar 2 again, the distance to the object can be measured. it can. Although the laser radar 2 can detect the presence or absence of an object at a long distance (100 m to several hundred m) in a short time, it cannot judge whether the object is an automobile.
On the other hand, in image processing using a camera, it is possible to accurately determine whether or not a target is an automobile, but it takes a long processing time until the determination is made. Therefore, the presence or absence of the object is detected by the laser radar 2, and when the presence of the object is confirmed, the roles are divided so as to detect the presence or absence of the car by performing image processing of the camera image by focusing on the detection area. Is also good. In this way, the preceding vehicle can be quickly and accurately detected. The laser beam 2a emitted from the laser radar 2 travels in a straight line, whereas the field of view of the camera 1 is 23 degrees. Therefore, when another vehicle suddenly breaks in front of the own vehicle, first, The laser beam 2a strikes another vehicle and is reflected (the other vehicle interrupted at this time is not in the field of view of the camera 1). Therefore, the detection of the interrupted vehicle is handled by the laser radar 2 which can detect the interrupted vehicle first and has a quick response. The controller 6 issues an overdrive-off command to the A / T 9 based on the inter-vehicle distance, the relative speed, etc., for example, when the current inter-vehicle distance is smaller than the safe inter-vehicle distance. Issues a throttle opening control command, and the brake actuator 4
Issue a brake command. Further, an alarm generation command is issued to the alarm buzzer 13 to call the driver's attention. The image processing section of the controller 6 performs image processing on an image photographed by the stereoscopic camera 1 and measures an inter-vehicle distance D between the vehicle and a vehicle recognized as a preceding vehicle. In controller 6, vehicle speed V _a, obtains a safe distance D _s from the relative velocity V _ba between the host vehicle and the preceding vehicle, high speed when the actual inter-vehicle distance D is smaller than the safe inter-vehicle distance D _s If so, an overdrive off command is issued to the A / T 9. As a result, the A / T 9 is shifted down to the third speed, the vehicle speed is reduced by the engine brake, and the safe inter-vehicle distance is maintained. As shown in FIG. 2, in this example, when the brake pedal 22 (see FIG. 1) is depressed, the brake pedal switch 7c is turned on and the stop lamp 21 is turned on. However, a relay 24 is added to this circuit, and the controller 6
The relay 24 is excited in response to a command from The controller 6 issues an excitation command signal when the estimated deceleration α is equal to or greater than a certain value. The estimated deceleration α is calculated by calculation as a deceleration corresponding to a torque fluctuation when the vehicle is shifted from the state of traveling in the overdrive state to the third speed. In practice, as shown in FIG. 4, the estimated deceleration THR1 (for example, 0.1 G) when the stop lamp 21 is turned on and the estimated deceleration THR when the stop lamp 21 is turned off.
2 (for example, 0.05G) to prevent hunting. Next, a control portion for turning on / off the stop lamp 21 in the command section of the controller 6 is shown in FIG.
This will be described with reference to the flowchart of FIG. First, when this subroutine starts, the stop lamp 21 is turned off (step (1)). Next, the estimated deceleration α is calculated (step (2)). The estimated deceleration is for estimating the deceleration according to the torque fluctuation when the vehicle is decelerated to the third speed as described above. However, the estimated operation value may be mapped and read from the map. Next, it is determined whether or not the stop lamp 21 is on (step (3)). If not, then the estimated deceleration α obtained by the calculation is T
It is determined whether it is larger than HR1 (for example, 0.1 G) (step (4)). If it is larger, the relay 24 is excited and the stop lamp 21 is turned on (step (5)). Thus, it is possible to notify the following vehicle that the own vehicle is in a deceleration state. In step (4), when the estimated deceleration α is THR
If it is determined that it is not greater than 1, the vehicle is in a deceleration state, but the deceleration is not so large, so that the stop lamp 21 is not turned on and the process returns to the calculation of the estimated deceleration α. If it is determined in step (3) that the stop lamp 21 is in a lighting state, it means that the stop lamp 21 is being lit during deceleration. In this case, the deceleration is decreasing due to the deceleration.
The calculated estimated deceleration α is THR2 (for example, 0.05
G) It is determined whether or not it is smaller (step (6)). If it is not determined to be small, the stop lamp 21 continues to be lit because the deceleration is still large. If it is determined that the estimated deceleration α is smaller than THR2, the stop lamp 21 does not need to be turned on, and is turned off (step (7)). In the above embodiment, the overdrive off of the A / T 9 is employed as a braking means for the own vehicle in order to maintain the inter-vehicle distance with the preceding vehicle or to avoid a collision. Can be similarly applied to a case where throttle control (engine brake control) and brake control are employed as braking means. That is, when a drive command is issued to the throttle actuator 3 or the brake actuator 4, the deceleration is estimated, and when it is estimated that the deceleration exceeds the threshold value, a stop lamp lighting command is output. According to the driving control apparatus for a vehicle according to the present invention, when a braking force is automatically applied based on the following distance, relative speed, and the like, the stop lamp is automatically turned on. Therefore, the deceleration state of the own vehicle can be notified to the following vehicle, and a rear-end collision can be prevented. In addition, since the stop lamp is turned on by estimating the deceleration, there is no delay in lighting and lighting can be performed in an appropriate scene.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a configuration diagram showing an automobile provided with an automobile traveling control device. FIG. 2 is a block diagram of one embodiment of the present invention. FIG. 3 is a flowchart of stop lamp lighting control. FIG. 4 is a diagram showing estimated deceleration and stop lamp on / off times. FIG. 5 is an explanatory diagram showing a method of detecting a white line by image processing. FIG. 6 is an explanatory diagram showing a method of detecting an inter-vehicle distance by image processing. FIG. 7 is an explanatory diagram showing the principle of triangulation by a stereoscopic camera. [Description of Signs] 1 Stereo camera 2 Laser radar 3 Throttle actuator 4 Brake actuator 5 Operation switch / information display unit 6 Controller 7 Vehicle speed sensor 7a Handle angle sensor 7b Brake switch 7c Brake pedal switch 7d Accelerator pedal switch 8 Engine 9 Automatic transmission 21 stop lamp 24 relay

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-59-188582 (JP, A) JP-A-4-358935 (JP, A) JP-A-4-215541 (JP, A) 3034 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB name) G08G 1/16 B60R 21/00 B60R 16/02 B60Q 1/44

Claims (1)

(57) [Claim 1] A vehicle in which a braking force is applied to the own vehicle by a braking means based on a distance between the own vehicle and a preceding vehicle or a relative speed between the own vehicle and the preceding vehicle. In the travel control device,
Cruise control of a motor vehicle characterized by comprising a stop lamp lighting device by Ri estimated deceleration which is estimated to braking force to light the stop lamp If so become more Tokoro <br/> value of said braking means apparatus.