JP2002063699A - Alarm system for vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an alarm system for vehicle for exactly raising the alarm of higher priority between two kinds of alarm, that is, lane deviation alarm and curve speed alarm corresponding to the traveling state of a present vehicle. SOLUTION: When the condition of the lane deviation alarm to be raised on the basis of an image photographed by a CCD camera 2 and a present car speed detected by a car speed sensor 3 and the condition of the curve speed alarm to be raised on the basis of road information or the like inputted from a navigation unit 5 are simultaneously established, if a deviation approach angle is smaller than a prescribed value or deviation direction is almost equal to the turning direction of a present vehicle or the condition of road surface under traveling is decided as a road surface condition easy to slip rather than a prescribed state, a control unit 1 preferentially outputs the curve speed alarm. But in the other case, the lane deviation alarm is preferentially outputted.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an alarm device for a vehicle, and more particularly, to an alarm device suitable for being mounted on a typical vehicle such as an automobile.

[0002]

2. Description of the Related Art Conventionally, in the case of an automobile, which is a typical vehicle, a device has been proposed which alerts a driver when a predetermined condition to be notified to a driver has occurred. For example, Japanese Patent Laid-Open No. 11-3
No. 4774 discloses an actuator provided on a steering mechanism of an automobile that vibrates the steering mechanism in order to notify the driver of a deviation from the driving lane.
There has been proposed an alarm device (tactile alarm device) that alerts a driver to danger by the vibration of the steering wheel generated thereby.

Japanese Patent Application Laid-Open No. 54-55923 discloses information on the permissible speed of a curve existing ahead from the road side, and based on the permissible speed, the own vehicle speed is used to safely drive the curve. There has been proposed an alarm device for notifying a driver when the speed is exceeded.

[0004]

According to the former alarm device, the driver who senses the danger can quickly perform the avoiding operation in the direction opposite to the departure direction, and according to the latter alarm device, Since a safe curve traveling can be performed, the driving operation by the driver can be efficiently supported.

[0005] Therefore, if an alarm system having such two types of alarm devices is mounted on a vehicle, it is expected that more efficient driving support can be performed.
If the conditions for starting the different types of alarms are satisfied at the same time and two different types of alarms are simultaneously performed,
As a general human characteristic, it is expected that the ability to judge an alarm is reduced, and the driver cannot easily determine which alarm should be dealt with.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide an alarm device for a vehicle that appropriately issues a high-priority alarm out of two types of alarms, a lane departure alarm and a curve speed alarm, according to the traveling state of the host vehicle. I do.

[0007]

In order to achieve the above object, a vehicular alarm system according to the present invention has the following features.

That is, a value relating to the amount of deviation from the running lane is detected, and when the predicted time until the vehicle departs from the lane becomes smaller than a predetermined value according to the detection result, the driver is notified of the fact. And departure avoidance warning means that warns against, while obtaining road information of the lane, calculating a safe vehicle speed for a curve ahead in the traveling direction based on the obtained road information, and in a situation where the vehicle speed is faster than the safe vehicle speed, When the estimated time required for the vehicle to reach the entrance of the curve is shorter than the required deceleration time required to reduce the vehicle speed to the safe vehicle speed, a curve speed that warns the driver to that effect. The warning means, the departure avoidance warning means, and the curve speed warning means, when the running condition of the host vehicle satisfies the conditions to perform the warning together, Of alarm means classes, characterized in that it comprises a warning controller for the departure avoidance alarm means is controlled to be executed with priority.

[0009] In a preferred embodiment, the alarm control means is configured to execute the departure even when the traveling state of the host vehicle satisfies a condition under which alarms by the two types of alarm means should be issued together. When the departure approach angle detected by the avoidance warning means is smaller than a predetermined value; when the departure direction detected by the departure avoidance warning means is substantially the same as the turning direction of the host vehicle; and If the slip ratio of the wheel of the own vehicle calculated by the above is larger than a predetermined value, the control is performed such that the curve speed warning means of the two types of warning means is executed with priority. Good.

[0010]

According to the present invention described above, a vehicle alarm device for appropriately issuing a high-priority alarm out of two types of alarms, a lane departure alarm and a curve speed alarm, according to the traveling state of the host vehicle. Is realized.

That is, according to the first aspect of the present invention, of the two types of alarm means, a departure avoidance alarm which is relatively likely to be accompanied by a physical obstacle when the alarm condition is not avoided by the driving operation by the driver. Since the means is executed with priority, the driver can perform an accurate danger avoidance operation with a margin.

According to the second aspect of the present invention, since the curve speed warning means is executed with priority, if the driver decelerates the vehicle speed in response to the warning, the vehicle will depart from the lane as a result. It will also delay the timing,
Effective danger avoidance is realized.

In general, when the lane departure direction is the same as the turning direction of the own vehicle, the turning curvature of the curve is increased by steering by the driver to avoid the departure, and the deceleration operation to the safe vehicle speed is performed. According to the third aspect of the present invention, the curve speed warning means is executed with priority in such a running state. Therefore, if the driver decelerates the own vehicle speed in response to the warning, the lane departure may occur. This also facilitates the avoidance operation, thereby realizing efficient danger avoidance.

In general, it is difficult for the driver to avoid the lane departure when the limit of the lateral force that can be generated on the wheel is reduced. When the slip ratio of the vehicle is larger than a predetermined value, the curve speed warning means is executed with priority, so that if the driver reduces the vehicle speed in response to the warning, the limit of the lateral force that can be generated on the wheels increases. Therefore, the operation of avoiding the lane departure is relatively easy, and efficient danger avoidance is realized.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a vehicle alarm device according to the present invention will be described in detail with reference to the drawings as an embodiment in which the alarm device is applied to a typical automobile.

FIG. 1 is a diagram showing the overall configuration of an automobile equipped with a vehicle alarm device according to this embodiment.

In FIG. 1, reference numeral 2 denotes a vehicle (vehicle 10).
This is a CCD (Charge Coupled Device) camera that photographs the front of 0). Reference numeral 3 denotes a vehicle speed sensor that detects the vehicle speed V. Reference numeral 4 denotes a wheel speed sensor that individually detects rotation speeds of four wheels of the vehicle 100. 5 is a vehicle 1 based on a GPS signal, road information, map information, and the like received from the outside.
00 is a navigation unit that detects the current position of 00 and guides a route to a set destination. Reference numeral 7 denotes a speaker that notifies the occupant of various kinds of information by voice.

The control unit 1 outputs a predetermined alarm sound from the speaker 7 based on the detection result of the sensor as one mode of an alarm (a lane departure alarm and a curve speed alarm) for the driver as described later. .

Incidentally, since the configuration itself of each block shown in FIG. 1 is common at present, detailed description in this embodiment will be omitted.

Next, an alarm control process performed by the control unit 1 using the detection results of the sensors shown in FIG. 1 will be described with reference to FIG.

FIG. 2 is a block diagram for explaining a control control process performed by the control unit of the vehicle alarm device according to the present embodiment. A microcomputer (not shown) provided in the control unit 1 stores a microcomputer in advance. FIG. 5 is a diagram schematically illustrating functions realized by executing a control program.

In FIG. 1, a control unit 1 is roughly divided into a lane departure warning process for preventing (avoiding) a departure from a traveling lane, and a stable traveling state for a curve existing in front of the traveling lane. And a curve speed warning process for giving a speed warning for safe traveling.

That is, the control unit 1 includes the CCD camera 2
(A white line or the like) that divides the traveling lane based on an image captured by the vehicle, and detects the detected line and a vehicle speed sensor 3
The lateral position (positional deviation) and the yaw angle of the own vehicle with respect to the traveling lane are detected based on the own vehicle speed detected by the vehicle, and the own vehicle deviates from the traveling lane based on the detected values. Estimate the expected departure time TLD. Then, when the estimated expected departure time TLD becomes equal to or less than the predetermined reference value T1, it is determined that the condition for performing the lane departure warning is satisfied.

Further, the control unit 1 calculates these two positions based on the current position obtained from the navigation unit 5 and the position of the entrance of the curve located ahead of the traveling lane.
Based on the relative distance between points and the own vehicle speed detected by the vehicle speed sensor 3, a curve arrival predicted time TCA required to reach the entrance of the curve from the current position is calculated and obtained from the navigation unit 5. On the basis of the safety speed calculated based on the curvature (1 / radius) of the curve (restricted vehicle speed at which the curve can be safely driven in a stable state) and the own vehicle speed, the vehicle is decelerated to the safety vehicle speed. The required deceleration time T2 is calculated. Then, when the calculated predicted curve arrival time TCA becomes equal to or less than the required deceleration time T2, it is determined that the condition for performing the curve speed warning has been satisfied.

Here, it is known that the safe vehicle speed is uniquely obtained according to the radius (curvature) of the curve.
The required deceleration time T2 is V for the vehicle speed, V0 for the safe vehicle speed, and a (a <a <
0), when the response delay time until the start of the deceleration operation is τ, it can be calculated by the formula of T2 = τ + (V0−V) / a.

A method for detecting the lateral position (displacement) of the own vehicle with respect to the traveling lane on the basis of the line dividing the traveling lane detected based on the image captured by the CCD camera 2, the own vehicle speed, the lateral position and Since the method of calculating the predicted departure time TLD based on the yaw angle and the method of calculating the predicted curve arrival time TCA are currently common, detailed description of each detection method in the present embodiment will be omitted. .

When the above two conditions for simultaneously issuing the alarms are satisfied at the same time, the control unit 1 gives an alarm of a higher priority to the driver as described later. Further, the priority order is determined based on the slip rate of the traveling wheel and the magnitude of the departure approach angle (the angle between the traveling direction of the own vehicle and the traveling lane) calculated based on the detection result of the wheel speed sensor 4, This is performed based on traveling conditions such as a departure direction (a direction in which the traveling direction of the host vehicle is based on the traveling lane).

Next, a procedure of an alarm control process of the control unit 1 for realizing the above-described operation will be described with reference to FIG.

FIG. 3 is a flowchart of an alarm control process of the control unit 1 in the present embodiment, and shows a procedure of a process performed by a CPU (not shown) of the control unit 1.

In the figure, step S1: the detection value of each sensor described with reference to FIG. 1 is updated.

Step S2, Step S3: Step S
1, the expected deviation time TLD (step S2) and the predicted curve arrival time TCA (step S
3) is calculated.

Steps S4 and S5: Based on the curvature of the curve ahead of the traveling lane obtained from the navigation unit 5, the safety speed of the curve is calculated (Step S4), and the own vehicle speed detected by the vehicle speed sensor 3 Time T required to decelerate the vehicle to the safe vehicle speed
2 is calculated (step S5).

Step S6: It is determined whether or not the predicted departure time TLD calculated in step S2 is equal to or less than a predetermined reference value T1, and TLD ≦ T1 (a condition in which a lane departure warning is to be performed). When TLD> T1, the process goes to step S7, and since lane departure warning is not required, the process goes to step S8.

Step S7: In the state where it is determined in step S6 that the condition for performing the lane departure warning is satisfied, in order to further break the state in which the curve speed warning should be performed, in this step, step S3 is performed. It is determined whether or not the predicted curve arrival time TCA calculated in step S5 is equal to or shorter than the required deceleration time T2 calculated in step S5.
When CA ≦ T2 (the condition for performing the curve speed warning is satisfied), the process proceeds to step S9. When TCA> T2, the process proceeds to step S13 because there is no need to perform the curve speed warning.

Step S8: In the state where it is determined that there is no need to issue a lane departure warning in step S6, in order to break whether or not a curve speed alarm should be issued, in this step, a curve is issued in the same manner as in step S7. A comparison is made between the predicted arrival time TCA and the required deceleration time T2, and TCA ≦ T
If it is 2 (the condition for performing the curve speed alarm is satisfied), the process proceeds to step S12, and if TCA> T2, the process returns because no alarm is required.

Steps S9 to S11: According to the determinations in steps S6 and S7, the current running state of the own vehicle is determined to satisfy the conditions for performing the lane departure warning and the curve speed warning, respectively. If two different types of alarms are simultaneously issued, the ability to judge an alarm is reduced as a general human characteristic, and the driver can easily determine which alarm should be dealt with. Tends to disappear. Therefore, if the judgment in each step from step S9 to step S11 is established, the process proceeds to step S12 to perform a curve speed alarm, and if none of the judgments in each of the steps is established, there is a possibility that a physical obstacle is accompanied. Proceeds to step S13 in order to issue a lane departure warning at a relatively high level. Less than,
Each determination step will be described.

Step S9: When the departure approach angle is smaller than the predetermined reference value A, even if it is necessary to issue a vehicle departure warning, the lateral component of the own vehicle speed in the current traveling state (the width direction of the own vehicle) Is relatively small, it can be determined that the urgency of issuing the vehicle departure warning is not too high. Therefore, in the present embodiment, in such a running state, the process proceeds to step S12, and the curve speed warning is executed with priority. As a result, if the driver decelerates the vehicle speed in response to the curve speed warning, the timing at which the vehicle departs from the lane is delayed as a result. Avoidance is realized.

Step S10: When the lane departure direction is the same as the turning direction of the host vehicle (that is, the turning direction that the host vehicle should take in the curve approaching), the driver reduces the curve vehicle speed to avoid the lane departure. Becomes difficult. Therefore, in the present embodiment, in such a running state, the process proceeds to step S12, and the curve speed warning is executed with priority. Accordingly, if the driver reduces the vehicle speed in response to the curve speed warning, the operation of avoiding the lane departure is also facilitated, so that efficient danger avoidance is realized.

Step S11: When the slip ratio (%) of the wheels of the own vehicle during running is larger than the predetermined reference value B, even if the driver performs an operation to avoid the lane departure, the deviation according to the operation is performed. It is more likely that the lateral force of the wheel that can avoid the above will not be generated. here,
The slip ratio (%) is obtained by calculating the average value of the wheel speeds of the driven wheels by Vre
f, the wheel speed of one of the drive wheels is Vf, and (1-
(Vf / Vref) × 100.

Therefore, in the present embodiment, even if it is necessary to issue a vehicle departure warning, when the lateral force that can be generated on the wheels is reduced (slip ratio> B), step S12 is performed. Go ahead and execute the curve speed alarm preferentially. Thus, if the driver reduces the vehicle speed in response to the curve speed warning, the lateral force that can be generated on the wheels is recovered (increased), so that the avoidance operation for the lane departure becomes relatively easy and efficient. Risk avoidance is realized.

Step S12: A predetermined warning sound for a curve speed warning is output from the speaker 7, and the process returns to step S1.

Step S13: A predetermined warning sound for lane departure warning (but different from the warning sound of the curve speed warning) is output from the speaker 7, and the process returns to step S1.

As described above, according to the present embodiment, a high-priority alarm out of two types of alarms, that is, a lane departure alarm and a curve speed alarm, is accurately notified according to the traveling state of the host vehicle. The driver can easily perform efficient danger avoidance.

[Brief description of the drawings]

FIG. 1 is a diagram showing an overall configuration of an automobile equipped with a vehicle alarm device according to an embodiment.

FIG. 2 is a block diagram illustrating an alarm control process performed by a control unit of the vehicle alarm device according to the embodiment.

FIG. 3 is a flowchart of an alarm control process of the control unit 1 in the embodiment.

[Explanation of symbols]

 1: control unit, 2: CCD camera, 3: vehicle speed sensor, 4: wheel speed sensor, 5: navigation unit, 7: speaker, 100: vehicle,

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Claims (4)

[Claims] When a predicted time until the vehicle departs from the lane becomes smaller than a predetermined value in accordance with the detection result, the driver is notified of the value. And departure avoidance warning means that warns against, while obtaining road information of the lane, calculating a safe vehicle speed for a curve ahead in the traveling direction based on the obtained road information, and in a situation where the vehicle speed is faster than the safe vehicle speed,
When the estimated time required for the vehicle to reach the entrance of the curve is shorter than the required deceleration time required to reduce the vehicle speed to the safe vehicle speed, a curve speed that warns the driver to that effect. The alarm means, the departure avoidance alarm means and the curve speed alarm means are both required to give an alarm when the traveling state of the host vehicle is satisfied. And a warning control means for controlling the avoidance warning means to be executed with priority. 2. The departure avoidance alarm means detects the condition that both of the two types of alarm means should be alarmed even when the traveling state of the host vehicle is satisfied. 2. The vehicle alarm according to claim 1, wherein when the departure approach angle is smaller than a predetermined value, control is performed such that the curve speed alarm is executed preferentially among the two types of alarms. apparatus. 3. The departure avoidance alarm means detects the condition under which the two types of alarm means should perform an alarm together, even when the traveling condition of the host vehicle is satisfied. When the departure direction and the turning direction of the host vehicle are substantially the same, control is performed such that the curve speed warning means of the two types of warning means is executed with priority. 2. The vehicle alarm device according to 1. Further, based on the wheel speed of the own vehicle,
A slip ratio calculating unit that calculates a slip ratio with respect to a road surface during traveling, wherein the alarm control unit is configured to execute the alarm when the traveling state of the host vehicle satisfies a condition under which both of the two types of alarm units are to be alarmed. Even when the slip rate calculated by the slip rate calculating means is larger than a predetermined value, the control is performed such that the curve speed warning means of the two types of warning means is executed with priority. The alarm device for a vehicle according to claim 1, wherein