JPH1096776A - Display device for inter vehicle distance - Google Patents

Abstract

PROBLEM TO BE SOLVED: To give a warning of a danger of a rear-end collision without making a driver feel troublesomeness by displaying an inter-vehicle area of a color according to a risk of a rear-end collision on a road in a head-up condition on the basis of the inter-vehicle distance and a safe inter-vehicle distance with a preceding vehicle recognized from a traveling condition of one's own vehicle. SOLUTION: An inter-vehicle distance detecting part 2 detects an inter-vehicle distance by time up to receiption of a reflected pulse from sending of a laser pulse of a laser beam sending receiving part 3. A data processor 1 sets an inter-vehicle area having a width in the same degree as one's own vehicle and a length of a detected inter-vehicle distance on a forward road. A safe inter- vehicle distance preregistered in a data memory 5 is read out, and a partial area of a different color according to a risk of a rear-end collision among a preset inter-vehicle distance is determined on the basis of the safe inter-vehicle distance and an actual inter-vehicle distance. Light emission according to a color and luminance of a display image is performed by a two-dimensional light emitting part 6c. A driver looks at a virtual image of an inter-vehicle area made on a road by being reflected by front glass 6d in a condition of being superimposed on a forward spectacle.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an inter-vehicle distance display device used in a vehicle collision warning system or the like.

[0002]

2. Description of the Related Art Hitherto, a collision warning system using a radar apparatus for transmitting and receiving a wave such as a laser beam, an electromagnetic wave, or a sound wave has been developed. When using a laser radar, this collision warning system detects the inter-vehicle distance from the preceding vehicle based on the propagation time required for the emitted laser beam to travel back and forth between the preceding vehicle, which is a reflector, and this detection value. When the vehicle speed falls below the safe inter-vehicle distance calculated from the vehicle speed of the host vehicle, the driver is warned of a danger of a rear-end collision with the preceding vehicle by a buzzer sound or the like.

[0003]

In the above-mentioned conventional collision warning system, the danger of a rear-end collision is warned by a buzzer sound or the like. However, there is a problem that the user feels troublesome. Further, a buzzer sounds suddenly when the inter-vehicle distance falls below a certain threshold, so that the driver often feels confused or shy. Therefore, the object of the present invention is to
It is an object of the present invention to provide a suitable inter-vehicle distance display method capable of warning a driver of a danger such as a rear-end collision without causing the driver to feel troublesome, embarrassed, or shy.

[0004]

An inter-vehicle distance display device according to the present invention includes an inter-vehicle distance detecting unit for detecting an inter-vehicle distance to a preceding vehicle, and a safety for the preceding vehicle based on a running state such as a vehicle speed of the own vehicle. A processing unit for recognizing an inter-vehicle distance, based on the detected inter-vehicle distance to the preceding vehicle, and the recognized inter-vehicle distance to the preceding vehicle, according to the risk of a rear-end collision between the own vehicle and the preceding vehicle. And a head-up display unit for head-up displaying the inter-vehicle area of the different colors.

[0005]

According to the embodiment of the present invention, red, yellow, and green are selected in descending order of the danger, so that the color corresponding to the danger is easily analogized to a traffic signal. You.

[0006]

FIG. 2 is a block diagram showing the configuration of an inter-vehicle distance display device according to one embodiment of the present invention. 1 is a data processor, 2 is an inter-vehicle distance detector, 3 is a laser transmitter / receiver, and 4 is An input interface unit, 5 is a data memory, 6 is a head-up display unit, and 7 is a key input unit.

The laser transmission / reception unit 3 is installed at an appropriate location such as the back side of the bumper of the vehicle or in the vehicle interior, and emits a pulsed laser beam from the light transmission unit toward the front of the vehicle. The emitted laser beam is reflected by a reflector such as a preceding vehicle existing in front of the own vehicle, and is received by a light receiving unit of the laser transmitting / receiving unit 3. The transmission of the laser pulse is performed in several different directions in front of the host vehicle based on a mechanical operation of the light transmitting and receiving unit.

The inter-vehicle distance detecting unit 2 calculates the propagation distance of the laser pulse from the time required for the laser transmitting / receiving unit 3 to transmit the laser pulse and receive the reflected pulse, that is, the distance between the vehicle and the preceding vehicle. The distance to the reflector, such as the distance, is detected. The detection of the distance to the reflector is performed in several different directions in front of the host vehicle as necessary. The inter-vehicle distance detection unit 2 is used for detecting the inter-vehicle distance in order to enhance detection accuracy such as elimination of interference by a laser beam emitted by another vehicle and removal of unnecessary reflected light from a reflector other than the preceding vehicle such as a corner reflector. Various processes are performed based on an appropriate algorithm. The inter-vehicle distance detection unit 2 detects the inter-vehicle distance between the preceding vehicle and the preceding vehicle by performing information exchange with a navigation system (not shown) or an analysis system for capturing an image of a scene ahead of the vehicle using a camera, if necessary. Improve accuracy further.

The data processor 1 includes an inter-vehicle distance detector 2
Receives data on the preceding vehicle, such as the inter-vehicle distance and direction, detected from the inter-vehicle distance detection unit 2 and stores the data in the data memory 5. Further, the data processor 1 determines the vehicle speed,
Traveling consisting of various data indicating the running state of the vehicle such as acceleration and steering angle, a light ON / OFF signal indicating daytime / nighttime, and a wiper ON / OFF signal indicating fine weather / rainy weather. Environment signals are received from various sensors and devices through the input interface unit 4 and stored in the data memory 5.

The data processor 1 is prepared based on an appropriate algorithm from the running state such as the running speed of the own vehicle in parallel with the process of storing the various data in the data memory 5 and registered in the data memory 5 in advance. The safe inter-vehicle distance to the preceding vehicle is read from the data memory 5. One of the algorithms for calculating the safe inter-vehicle distance is, for example, as shown in FIG. That is,
The safe inter-vehicle distance Ls is determined based on the vehicle speed V of the host vehicle, the driving environment such as time zone (daytime / nighttime), and weather (fine weather / rainfall), and the more the vehicle speed V increases and the more the driving environment deteriorates, The inter-vehicle distance Ls is set to a large value.

The data processor 1 receives a signal indicating whether or not the headlight is operating from the corresponding control circuit via the input interface unit 4 as information on the daytime and nighttime zones. The data processor 1 includes, as information relating to the weather, whether or not the wiper is operating, if it is operating, at what cycle it changes according to the amount of rainfall, or whether or not the fog lamp is lit. Is received from a control circuit such as a wiper or a fog lamp (not shown) via the input interface unit 4 to recognize the traveling environment, and reads the safe inter-vehicle distance from the data memory 5 based on the result and the vehicle speed.

As shown in FIG. 4, the data processor 1 has a width similar to that of the host vehicle on a road ahead of the host vehicle.
An inter-vehicle region having the length of the detected inter-vehicle distance L and connecting the host vehicle and the preceding vehicle is set. Next, based on the safe inter-vehicle distance read from the data memory 5 and the actual inter-vehicle distance detected by the inter-vehicle distance detection unit 2, the data processor responds to the risk of rear-end collision in the set inter-vehicle area. Determine the partial areas of different colors. For example, in the set inter-vehicle area, the safe inter-vehicle distance L from the preceding vehicle
Green coloring indicating that the risk of a rear-end collision is the lowest is performed on a partial area of the front length (L-Ls) of the host vehicle separated by s or more.

Next, in the inter-vehicle area between the host vehicle and the preceding vehicle, a rear collision with a partial area shorter than the safe inter-vehicle distance but larger than 70% (0.7 Ls) thereof from the preceding vehicle is considered. A yellow color indicating that the risk is the second highest is performed. Finally, of the inter-vehicle region between the host vehicle and the preceding vehicle, a red region indicating that the rear-end collision risk is the highest for a partial region shorter than 70% of the total inter-vehicle distance from the preceding vehicle. Perform coloring. The coloring with the different colors may be performed so as to fill the entire area within the frame of the corresponding partial area, or may be performed so as to color only the frame.

The data processor 1 converts the inter-vehicle area illustrated in FIG. 4 into a bird's-eye view of the road viewed from the driver's eye level and writes it into the screen memory 6a of the heads-up display unit 6 together with coloring information. . The display controller 6b includes a screen memory 6a
Is read out at regular intervals, and the two-dimensional light-emitting portion 6c composed of a liquid crystal display panel or the like is caused to emit light according to the color and luminance of the display image. The two-dimensional light emitted from the light emitting unit 6c is reflected by the windshield 6d and enters the driver's eyes. The driver creates a virtual image of the inter-vehicle area created on the road by extending this reflected light outside the vehicle,
As illustrated in FIG. 1, the user looks over the scene in front of the host vehicle actually viewed through the windshield. Further, when the detected inter-vehicle distance becomes about half of the safe inter-vehicle distance, in addition to the above-described red display warning, a buzzer alarm is also generated in case of a failure of the display device or driving aside.

FIG. 5 is a conceptual diagram for explaining a method of displaying an inter-vehicle distance by an inter-vehicle distance display device according to another embodiment of the present invention. In this embodiment, as illustrated in (A), on the road ahead of the host vehicle, the vehicle has a width similar to that of the host vehicle and a length L of the inter-vehicle distance and has a length between the host vehicle and the preceding vehicle. If the detected inter-vehicle distance L is larger than the recognized inter-vehicle distance Ls, a green color indicating that the risk of a rear-end collision is the lowest over the entire inter-vehicle area is set. Do.

The inter-vehicle distance is smaller than in the case of (A),
When the detected value L reaches a value between the safe inter-vehicle distance Ls and its 70% value (0.7 Ls <L ≦ Ls), the risk of rear-end collision becomes second over the entire inter-vehicle area as shown in FIG. A yellow coloration indicating high is performed. If the inter-vehicle distance further decreases than in the case of (B) and the detected value L becomes a value less than 70% of the safe inter-vehicle distance Ls (L <0.7),
As shown in (C), red coloring indicating that the risk of a rear-end collision is the highest over the entire inter-vehicle area is performed.

In the display method according to the embodiment described with reference to FIG. 4, the risk of rear-end collision is higher in a partial area in which the own vehicle exists among the set inter-vehicle areas based on the preceding vehicle. It is configured to display in red, yellow, and green in order. That is, as shown in FIG. 4, the risk of rear-end collision is minimized when the host vehicle is in the green partial region, and the rear-end collision risk is low when the host vehicle is in the red partial region. Will be the best.

Conversely, the danger of a rear-end collision is displayed in red, yellow, and green in ascending order of the partial area in which the preceding vehicle exists in the set inter-vehicle area based on the own vehicle. You can also. That is, as shown in FIG. 6, if the preceding vehicle exists in the green partial area, the risk of rear-end collision is minimized, and if the preceding vehicle exists in the red partial area, the risk of rear-end collision occurs. Will be the best.

Which of the three types of coloring methods described with reference to FIGS. 4, 5, and 6 is to be adopted can be determined in advance, or can be determined according to the driver's preference and familiarity. Accordingly, the selection can be made by key input from the key input unit 7 in FIG. 2 or operation of a changeover switch (not shown).

As described above, an example has been described in which the inter-vehicle region is set to have the same width as the own vehicle connecting the preceding vehicle and the own vehicle and the same length as the detected value of the inter-vehicle distance. However, the predicted traveling locus of the own vehicle is calculated from the vehicle speed, acceleration, steering angle, yaw rate, estimated value of the friction coefficient between the tire and the road surface, and the like, and a width similar to the width of the own vehicle is calculated in the predicted traveling locus. By adopting a configuration in which the given one is set as an inter-vehicle area to be colored as illustrated in FIGS. 4, 5, and 6,
It is possible to effectively cope with a more practical situation such as a case where a road curves.

[0021]

As described above in detail, the inter-vehicle distance display apparatus according to the present invention is capable of displaying the inter-vehicle distance between a preceding vehicle detected by a laser radar or the like and the preceding vehicle recognized from the traveling state of the own vehicle. Based on the safe inter-vehicle distance, a head-up display of the inter-vehicle area of red, yellow, green, etc. according to the risk of rear-end collision on the road between the host vehicle and the preceding vehicle is displayed, so a buzzer etc. generates an alarm Unlike conventional devices that
This has the effect that the driver can be warned of a danger such as a rear-end collision without causing the driver to feel troublesome.

In addition, since the red display which is a serious warning for a rear-end collision is performed after the green display stage through the yellow display stage, the driver suddenly issues an alarm like a buzzer sound. You won't feel embarrassed or shy at the time.

[Brief description of the drawings]

FIG. 1 is a diagram for explaining a method of displaying an inter-vehicle distance by a display device according to an embodiment of the present invention.

FIG. 2 is a block diagram showing a configuration of an inter-vehicle distance display device according to the embodiment.

FIG. 3 is a graph for explaining an example of a relationship between a vehicle speed of a host vehicle, a bad environment, and a safe inter-vehicle distance in the apparatus of the embodiment.

FIG. 4 is a conceptual diagram for describing a method of displaying an inter-vehicle distance by the display device according to the embodiment.

FIG. 5 is a conceptual diagram for explaining a method of displaying an inter-vehicle distance by a display device according to another embodiment of the present invention.

FIG. 6 is a conceptual diagram for explaining a method of displaying an inter-vehicle distance according to still another embodiment of the present invention using a display device.

[Explanation of symbols]

 1 Data processor 2 Inter-vehicle distance detector 3 Laser transmitter / receiver 4 Input interface 5 Data memory 6 Head-up display

Claims (5)

[Claims] 1. A distance detecting section for detecting an inter-vehicle distance to a preceding vehicle; a processing section for recognizing a safe inter-vehicle distance to a preceding vehicle based on a traveling state such as a vehicle speed of the own vehicle; A head-up display unit that head-up displays an inter-vehicle area of a different color according to the risk of a rear-end collision between the own vehicle and the preceding vehicle based on the inter-vehicle distance and the recognized safe inter-vehicle distance with the preceding vehicle; A display device for an inter-vehicle distance, comprising: 2. The inter-vehicle distance display method according to claim 1, wherein the inter-vehicle area is displayed in the length direction with a plurality of partial areas colored differently according to the risk of a rear-end collision. 3. The inter-vehicle distance display method according to claim 1, wherein in the inter-vehicle area, only one colored area different in accordance with the risk of a rear-end collision is displayed in the length direction. 4. The inter-vehicle distance display device according to claim 1, wherein the color according to the risk is selected from red, yellow, and green in descending order of the risk. 5. The inter-vehicle distance display device according to claim 1, wherein the inter-vehicle region is a predicted traveling trajectory of the own vehicle having a width similar to that of the own vehicle.