DE102007027000A1 - Lane holding assistant for vehicle, has lane detection device for detecting deviation of vehicle from traffic lane, and warning device for warning driver based on deviation of vehicle and driver activity - Google Patents

Abstract

The assistant (1) has a lane detection device (3) that detects deviation of a vehicle from a traffic lane. A warning device is provided for warning a driver based on the deviation. An activity device (6) determines a driver activity from temporal characteristics of position of a control element e.g. steering wheel. The warning device warns the driver based on the deviation of the vehicle and the driver activity. An independent claim is also included for a method for warning a driver of a vehicle.

Description

The The invention relates to a lane departure warning system for a vehicle, wherein the lane departure warning assistant a track detection device for detecting a deviation of the Vehicle from the lane and a warning device to warn the driver Driver in dependence covered by the deviation. The invention further relates to a method to warn the driver of a vehicle when leaving the lane as well as a vehicle equipped with a lane departure warning is.

Lane Departure Warn the driver of a vehicle from unconsciously leaving the lane so he can drive his vehicle through active steering back into the lane can lead back. For example, the vehicle may unconsciously ignore the lane leave because the driver falls asleep or inattentive for a brief moment is. If the driver with his vehicle from the lane, arises the risk that the driver loses control of his vehicle or collided with other vehicles. To reduce these dangers, Lane departure warning systems have been developed.

Known Lane departure warning systems detect the position of the vehicle relatively to the lane and then give a warning if a certain Distance to a lane marking, for example the edge of the lane, is fallen short of. The warning is audible, visual or haptic.

In the known lane departure warning systems, it is problematic to set a limit value for the distance to the lane marking, below which the warning is issued:
If the distance is too large for the limit, then the warning is often in such cases, in which there is no dangerous situation. Thus, there is a high rate of "false alarms." Getting used to the "false alarms" causes the driver to ignore a warning in an actual critical situation and not respond adequately to the warning.

Becomes the distance for chosen the limit relatively small, a warning comes very late. At a very late Warning creates the danger that the time for a required reaction is no longer sufficient, so the vehicle is no longer in time the lane can be steered. In this case, the lane departure warning system a low sensitivity (Recognizing dangerous Conditions) on.

One Another problem arises from the fact that the reaction time of the driver the slower, depending inattentive or tired the driver is. The influence of the driver's attention becomes but not included in the static limits.

task The invention is therefore an initially mentioned lane departure warning to improve that the lane departure warning a high sensitivity at a simultaneously low rate of "false alarms".

The The object is achieved by a generic lane keeping according to the invention solved, in that the lane departure warning system comprises an activity facility which is formed, from the time course of the setting at least a control element to determine a driver activity, and that the Warning both in dependence from the deviation as well as depending on the driver's activity.

• – Erkennen einer Abweichung des Fahrzeugs von der Fahrspur;
• – Ermitteln einer Fahreraktivität;
• – Warnen des Fahrers in Abhängigkeit sowohl der Abweichung als auch der Fahreraktivität.

The invention is further achieved by a method for warning the driver of a vehicle when leaving the lane, according to the invention comprising the steps:

• Detecting a deviation of the vehicle from the lane;
• - determining a driver activity;
• - Warning the driver depending on both the deviation and the driver's activity.

Under "Driver Activity" is a rating the driver to understand to what extent this driver currently involved in the vehicle operation.

Of the Lane keeping assistant according to the invention does not work with a given static limit, but determines a driver activity, which has an impact on the limit.

If a high driver activity is determined, this speaks for a high attention of the driver. With a high attention of the driver, it is justifiable to increase the limit accordingly, so that a warning is issued relatively late. This late warning is also desirable: Firstly, the driver is able to respond to a warning in a relatively short time and the vehicle in good time in high driver activity attributed to the lane. On the other hand, the driver is not bothered with a high rate of false warnings that cause the driver to stop responding to the warnings with due attention.

is the driver is inactive, so there is a possibility that this on one Inattention or tiredness of the Driver is based. The lane-keeping assistant according to the invention sets in this case the limit for the warning to a relatively clotting conditions Value. this leads to to that the warning is done relatively early, so even one Inattentive driver has sufficient time to secure the vehicle to divert back into the traffic lane.

Of the Lane keeping assistant according to the invention has the following advantages: The rate of false alarms reduced. If the driver is active, he will only be warned if he is very is close to the lane marking. If the driver is not active, He is already warned when he is still with his vehicle further away from the lane marker.

Of the Lane Keeping Assist has a high sensitivity even in cases in which the driver is tired or is distracted and therefore deviates from the track.

Be useful considers such controls for determining driver activity, the essentially continuous information about the provide up-to-date driver attention. So it should be controls be that while a total journey possible often deliberately actuated become. In particular, drive elements are considered (eg. Accelerator pedal), brake elements (eg brake pedal) or steering elements (eg. B. steering wheel). But it is also to think about direction indicators or couplings.

Be useful the settings are recorded periodically. This ensures, on the one hand, that the settings are recorded regularly and changes can be easily determined. On the other hand, the periodic recording of the settings is technical easy to realize.

In Modern vehicles are used for fast data transfer between ECUs Bus system used, in particular a CAN bus (CAN: Controller Area Network). In such vehicles, the values of the settings appropriate over the Transfer bus system. In this way it is possible the lane keeping assistant according to the invention without big ones renovations and therefore cost-effective to install in known vehicles.

The activity of the driver leaves Reliable about changes of settings. When consciously changing a setting is the driver's attention required. A conscious change a setting is thus suitable, an activity of the driver express.

Is appropriate the activity facility trained, for each setting to determine the amount of time since the last change the setting has passed. In this way, a rate of change the setting determined for the assessment of driver activity is used.

It can happen that changes Although measurable, but not on a conscious behavior of the driver decline. Such changes do not contain any useful information for evaluating driver activity. Therefore it is appropriate to make a change only then to consider if the change exceeds a predefined threshold.

In an embodiment are for the duration of each setting determines at least two time intervals, assigned the different ratings of driver activity are. That way the driver activity categorize, for example, into the categories "active" and "inactive" or into the categories "active", "quiet" and "inactive." In the first example becomes the driver's activity divided into two parts, in the second example in three. Of course you can the classification will be further refined to reflect any specificities consider to be able to. To think would be about the type of vehicle: z. As cars or trucks. It is also conceivable the adaptation to different traffic situations: z. B. rides predominantly on the highway or country road, City driving. possibly The classification can also be made dependent on the characteristics of the driver be: z. B. Driver with a lot of experience or novice driver.

In one embodiment it is provided that the warning device is designed to output the beginning and the intensity of the warning as a function of both the deviation and the activity. Thus, in this embodiment, not only the timing of the warning is made dependent on the driver's activity, but also the type of warning. With regard to the intensity of the warning, for example, the following Intensities: weak warning, strong warning, assistance with intervention, strong warning with assistance or reaching a safe state.

The Warning device may be formed according to the invention, the warning acoustically, optically, haptically and / or through intervention in the vehicle control leave. An optical display is for example via a central display or a head-up display possible.

Is appropriate the track detection device with infrared sensors, laser sensors and / or video sensors. Such sensors are suitable capture the environment of the vehicle and, if necessary, in one To evaluate image processing device. Preferably, different Sensors combine accuracy and reliability to increase the evaluation.

Is appropriate the lane detection device is formed, the deviation by Comparison of the current position of the vehicle or a future one Determine position of the vehicle with a lane marking. It is conceivable z. B., the current center of the vehicle with the center of the road or the edge of the lane. Regarding the future Position of the vehicle comes, for example, the detection of the cross-shelf into consideration.

Also according to the invention a vehicle provided that with a lane departure warning according to the invention Is provided.

The Invention is illustrated by the in the following figures embodiment explained in more detail. It demonstrate:

1 a block diagram of a lane departure warning according to the invention,

2 a block diagram for determining an activity of the driver and

3 a schematic course of a vehicle on a road.

In 1 is schematically a lane departure warning 1 shown.

The Lane Keeping Assist 1 includes sensors 2 , The sensors 2 are used to detect the lane on a road and to detect a deviation of the vehicle from the lane. In the present embodiment, the sensors are video sensors, in particular optical cameras, which image the surroundings of the vehicle. The output signals of the sensors 2 are sent to a track detection device 3 transfer. The track recognition device 3 evaluates the images of the sensors 2 out. For this purpose, the track recognition device 3 equipped with an image processing device. The track recognition device 3 transmits the result of the evaluation to a warning device 4 ,

The Lane Keeping Assist 1 includes sensors 5 , which detects drive settings of a driver-operable input member (eg, accelerator pedal), brake settings of a driver-operable brake member (foot brake), and steering adjustments of a driver-operable steering member (steering wheel). The output signals of the sensors 5 be sent to an activity facility 6 transfer. The transmission takes place periodically at about 10 Hz. The transmission of these output signals takes place in the present embodiment via a CAN bus system of the vehicle.

The activity facility 6 comprises a memory unit and a computer unit, which are formed from the output signals of the sensors 5 to calculate an activity of the driver. The calculated activity is sent to the warning device 4 transfer.

The warning device 4 thus obtains data expressing driver behavior (from the lane detection device 3 ) and data expressing driver activity (from the activity facility 6 ). These data together form a two-dimensional matrix, from which the whether and the like of a warning can be taken.

Tabelle 1 Table 1 below shows such a matrix:

Table 1

The driver activity is divided into three areas: "active", "quiet" and "not active ". Driver behavior is also divided into three areas: "safe", "uncertain", "dangerous / critical".

In the matrix, the different warning options are entered in the matrix elements assigned to the driver activity and the driver behavior. For example, the matrix element (active, safe) has the entry "system active." This means that the driver is merely informed that the system is active, for example, via an optical element, such as an LED If the matrix element (active, uncertain) is given a weak warning, for example in the form of an acoustic signal, the matrix element (not active, dangerous / critical) is provided with the lane departure warning 1 engages the vehicle control and the vehicle leads to a safe state, for example, brings to a standstill on the roadside.

Tabelle 2 Table 2 below shows another matrix:

Table 2

in this connection it is a 2 × 3 matrix, at the driver's activity into the two areas "active" and "not actively "divided is. The possible Restrict warnings on a soft and a loud Nagelbandratterntern. The driver behavior is divided into three areas: "safe area", "more dangerous Range "," more critical Area".

The Driver behavior is based on the future position of the vehicle, the above the cross-shelf is defined. Dodge the cross shelf from the middle of the track not more than 0.2 m away, the driver's behavior is classified as "safe" a deviation of the cross shelf from the track center, which is greater than 0.2 m but less than 0.3 m, the driver behavior is classified as "uncertain" a deviation of the lateral deviation from the center of the track over 0.3 m is the driver behavior as "dangerous / critical" classified.

The warning device 4 gives a warning according to the entries in the matrix. Present is via a microphone 7 An audible tone is emitted to increase the driver's attention.

In 2 is the activity facility 6 shown in more detail.

The activity facility 6 includes reception facilities 9a , b, c, which read at a frequency of about 10 Hz data from the CAN bus system of the vehicle.

The receiving device 9a receives the setting of the accelerator pedal. The setting corresponds to the extent to which the driver presses the accelerator pedal. The setting is a value from the interval 0% to 100%. 100% corresponds to the fully depressed accelerator pedal.

The receiving device 9b receives the brake pressure of the foot brake. The brake pressure is a value from the interval 0 bar to 250 bar.

The receiving device 9c receives the steering wheel angle. The steering wheel angle is from the interval -1,400 ° to + 1,400 °.

For this becomes three sizes each calculated the difference to the previous received value. The result is a sequence of value differences or changes, which are also obtained with a frequency of 10 Hz. To coincidental, not to avoid meaningful differences, only changes are considered, the above a predefined threshold. In the present example the threshold values are set as follows: a) Accelerator pedal: 1% based on the interval 0% to 100%; b) Brake pedal: 1.5 bar to the interval 0 bar to 250 bar; c) Steering wheel: 0.5 ° to the interval -1.400 ° to + 1.400 °.

For each signal, the difference serves as an index of the driver's activity. If at least one of the signals has changed, an overall activity is assumed at that time. This can be done, for example, by assigning the value "1" (active) .If one of the signals has changed during a period, the total activity is set to the value "0" (not active). The total activity is through a module 11 provided.

Is the activity in the module 11 If the value is "0", the duration of inactivity is summed up in a module 12 ,

About one suitable threshold for the duration of inactivity An index is calculated that represents a measure of driver activity.

The activity is in a module 13 calculated. In the calculation of the driver's activity is also advantageous, the speed v of the vehicle 15 considered.

The activity is finally output in the form of a value "0" (not active), "0.5" (quiet) and "1" (active) and to the warning device 4 transfer.

The determination of the activity taking into account the speed v of the vehicle 15 The duration of inactivity is set to zero as soon as a driver's activity is measured, for example because the driver has applied the brake.

He follows no change one taken into account Setting, the duration of inactivity is measured.

These Duration is for classified different speeds.

For speeds Below 60 km / h, two thresholds are set as follows: 3 Seconds and 8 seconds. These thresholds lead to the three intervals with the assigned activities: under 3 seconds ("1" or "active"), between 3 and 8 seconds ("0.5" or "quiet"), over 8 seconds ("0" or "inactive").

For speeds between 60 km / h and 110 km / h, two threshold values become as follows set: 4 seconds and 9 seconds. These thresholds lead to the three intervals with the assigned activities: under 4 seconds ("1" or "active"), between 4 and 9 seconds ("0.5" or "quiet"), over 9 seconds ("0" or "inactive").

For speeds between over 110 km / h, two thresholds are set as follows: 6 seconds and 12 seconds. These thresholds lead to the three intervals with the assigned activities: under 6 seconds ("1" or "active"), between 6 and 12 seconds ("0.5" or "quiet"), over 12 seconds ("0" or "inactive").

In 3 is schematically a part of a roadway 15 shown. On the roadway 15 a vehicle is moving 16 at a speed v along the roadway 15 ,

On the roadway 15 is a lane 17 shown in dashed lines. The lane 17 in this case is the center line of the roadway 15 , The vehicle 16 moves with its center (not shown) on the lane 17 ,

By suitable sensors (not shown), the future vehicle position is extrapolated based on the current speed v. The distance d of the future vehicle position 18 from the lane 17 is the cross-shelf of the vehicle 16 that as deviation from the lane 17 is used.

1

Lane Departure

2

sensors

3

Lane detection device

4

warning device

5

sensors

6

activity unit

7

speaker

8th

vehicle control

9a b, c

receiving devices

10

CAN bus

11

module

12

module

13

module

14

speed

15

roadway

16

vehicle

17

lane

18

Future vehicle position

Claims (15)

Lane Keeping Assist for a vehicle, with the Lane Keeping Assist ( 1 ) a track recognition device ( 3 ) for detecting a deviation of the vehicle ( 16 ) from a lane ( 17 ) and a warning device ( 4 ) for warning the driver as a function of the deviation, characterized in that the lane departure warning system comprises an activity device ( 6 ), which is designed to determine a driver activity from the time profile of the setting of at least one operating element, and that the warning takes place both as a function of the deviation and as a function of the driver's activity. Lane departure warning system according to claim 1, characterized in that that the at least one operating element is a drive element, in particular an accelerator pedal. Lane departure warning system according to claim 1 or 2, characterized characterized in that the at least one operating element is a brake element is, in particular a brake pedal. Lane departure warning according to one of the preceding claims, characterized characterized in that the at least one operating element is a steering element is, in particular a steering wheel. Lane departure warning system according to one of the preceding claims, characterized in that the activity device ( 6 ) is designed to detect the settings periodically. Lane departure warning system according to one of the preceding claims, characterized in that the activity device ( 6 ) is configured, the settings from a bus system ( 10 ) read out. Lane departure warning system according to one of the preceding claims, characterized in that the activity device ( 6 ) is adapted to determine for each setting the time that has elapsed since the last change of the setting. Lane departure warning system according to claim 7, characterized in that that for the duration of each adjustment at least two time intervals are assigned to the different ratings of driver activity are. Lane departure warning according to one of the preceding claims, characterized in that the warning device ( 4 ) is adapted to deliver the beginning and the intensity of the warning as a function of both the deviation and the driver's activity. Lane departure warning system according to claim 9, characterized in that the warning device ( 4 ) is formed to deliver the warning acoustically, visually, haptically and / or by engaging in the vehicle control. Lane departure warning system according to one of the preceding claims, characterized in that the lane recognition device ( 3 ) Comprises infrared sensors, laser sensors and / or video sensors. Lane departure warning system according to one of the preceding claims, characterized in that the lane recognition device ( 3 ) is formed, the deviation by comparing the current position of the vehicle ( 16 ) or a future position of the vehicle ( 16 ) with a lane marking. Method for warning the driver of a vehicle ( 16 ) when leaving the lane with the steps: - detecting a deviation of the vehicle ( 16 ) from the lane ( 17 ); - determining a driver activity; - Warning the driver depending on both the deviation and the driver's activity. Method according to claim 13, characterized in that it is equipped with a lane keeping assistant ( 1 ) is carried out according to one of claims 1 to 12. Vehicle with a driver assistance system after a the claims 1 to 12.