EP1535257B1 - Device and method for radio-based danger warning - Google Patents

Description

The invention relates to a device for radio-based hazard warning according to the preamble of claim 1 and a method for radio-based hazard warning according to the preamble of claim. 6

In EP 927 983 A2 a device for radio-based hazard warning is described, in which the difference in the speeds of sending and receiving vehicle is determined in a vehicle receiving the hazard warning and based on the determined speed difference, the decision is made whether a warning signal is output to the driver.

In FR 2 793 056 A device for warning the danger is described, in which the type of danger is indicated in the vehicle. In the receiving vehicle is determined whether it is necessary to send the warning to other vehicles.

In the WO 01/61668 A1 a device is described for the hazard warning, in which a warning zone is generated in the transmitting vehicle and sent out together with the danger warning. In the sending vehicle, the position of the vehicle and the road type on which the vehicle is located are determined using a navigation system. In the calculation of the warning zone in the transmitting vehicle, the speed difference between the speed of the transmitting vehicle and the typical or maximum speed of other vehicles on the given road type is included. The evaluation of the received hazard warning in the receiving vehicle is carried out using a navigation system by checking whether the receiving vehicle in the Warning Zone is located and whether the hazard warning relates to a potentially lying in front of the receiving vehicle section.

From the document "WARN - a new radio-based hazard warning system in the vehicle for more safety on the road", Brenzel, C., Hickel, F., Paßmann, C., VDI reports No. 1415, 1998, it is known, along with the hazard warning the type of risk to transmit the speed of the sending vehicle, as well as information about the position of the sending vehicle. In the receiving vehicle, the differential speed is determined to the sending vehicle. Vehicle position information is used to determine if the alert was generated by a preceding or succeeding vehicle or by oncoming traffic.

From the document "Wireless Vehicle to Vehicle Warning System", Paßmann, C., Brenzel, C., Meschenmoser R., SAE-Paper, 2000-01-1307, it is known to display in the receiving vehicle icons, the type of Symbolize danger. The receiving vehicle also displays the distance to the danger location.

It is off DE 199 52 392 A1 a method is known in which the driver route-dependent warning information is provided. Using digital road maps, for example, it is detected whether the driver is approaching a curve ahead. If the current speed of the vehicle is greater than a cornering speed limit, the driver is first visually warned. If the driver does not respond to the visual warning within a certain time, ie if he continues to drive at undiminished speed, an additional acoustic warning will be issued. Since the curve has a fixed position, the approach to a curve is always detected at a sufficiently great distance before the curve and different Warning levels of increasing urgency are triggered one after the other.

From the GB 2 349 000 A a radio warning system is known in which vehicles in hazardous situations transmit their position, speed and direction of each other by radio. If a vehicle receives such data from another vehicle, it is determined whether the values of these data are within critical ranges. In this case, a warning is issued to the driver of the data receiving vehicle.

In the WO 00 17016 A1 An obstacle warning device for vehicles is described. Both a near field for parking processes is sensory monitored as well as a larger environment for shunting. Various signals are used to warn of obstacles in the two different zones. To illustrate a continued approach to the obstacle, the issued warning signals can be intensified.

The invention is based on the object of providing an apparatus and a method for radio-based hazard warning, by means of which - especially with regard to traffic situations in overland traffic - an improved information output to the driver is realized.

This object is solved by the features of claim 1 and by the features of claim 7. The dependent claims relate to advantageous embodiments and further developments of the invention.

The basic idea of the triggering concept according to the invention is to include in the decision as to whether information is output to the driver, at least the approaching speed of the transmitting and receiving vehicle and the distance between the two vehicles. This is the invention The fact that the urgency of a warning is especially crucial to how much time the driver is given to respond to the warning and decelerate his vehicle. However, this time is calculated at least from the distance and the relative speed of receiver and transmitter, so that both variables for the triggering concept, ie the decision as to when an information is output and when the output is terminated, are decisive. The decision as to whether information is output to the driver takes place in the evaluation of a received radio message in a computer unit in the receiving vehicle.

By linking the distance to the approach speed, the time remaining until reaching the transmitter becomes the determining quantity for the triggering concept. This also corresponds to the human perception of road hazards. The driver assesses the danger of a situation mainly after the time remaining to him to perform necessary actions and driving maneuvers to avoid an accident.

No warning is triggered if the distance to the transmitter is so great or the approach speed is so short that there is initially no need for action on the part of the driver. Likewise, if desired, the tripping concept can be designed to forego the triggering of a warning if the distance is so short or the approach speed so high that the driver no longer adequately responds to the event due to the short pre-warning time Warning could react.

Using the distance between the transmitting and the receiving vehicle and using the approaching speed of the transmitting and receiving vehicles, an emergency level for the information output is determined.

The urgency of a warning is inventively determined depending on the time since the last warning time. If two warnings follow each other at short intervals, then it can be assumed that the driver is driving with increased attention due to the first warning. Therefore, the second warning may be assigned a low level of urgency even if the transmitter is reached shortly.

The way in which information is provided to the driver depends on the level of urgency determined. In this way, the distance and the relative speed of receiver and transmitter for the type of output of information prevail.

The urgency level depends on when the driver informs about a received radio message and how this information or warning is output to the driver. This is particularly important for the high speeds used on motorways, where the driver must concentrate fully on the task of driving and only to a limited extent be able to record additional information and warnings issued by a vehicle system. The driver can intuitively understand the warning and react to it correctly.

The invention provides e.g. Massive carcass prevents the z. On freeways where multiple vehicles are involved and which often travel in poor visibility conditions, e.g. Fog, on confusing sections, e.g. behind a poorly visible curve or due to traffic jams, e.g. Jamming, construction site, happen. The radio-based hazard warning device enables the drivers of subsequent vehicles to recognize the danger ahead of them in a timely manner and then be able to brake their vehicle in good time. In one embodiment of the invention, it is possible to provide that the vehicle is automatically braked by an intervention in vehicle control systems.

In addition to the distance and the approach speed of receiver and transmitter, in a further embodiment of the invention further data can be taken into account in order to decide on the triggering of a warning and its urgency level. As examples are the speed and Acceleration of the receiving vehicle and the time since the last warning called. For example, route information can also be used to determine the level of urgency. Fahrstreckehinformationen be determined for example by means of a digital road map.

Thus, it is advantageous to trigger a warning only when the receiver drives sufficiently fast, as at low speeds, a timely visual recognition of the danger by the driver ensures and thus an additional system-side warning is superfluous.

It can also be checked on the basis of the current vehicle acceleration, whether the driver of the receiver already brakes hard enough to avoid driving on the transmitter. Also in this case can be dispensed with a warning.

The radio-based hazard warning device generates a hazard warning that extends beyond the optical range of a hazard warning device. As a result, an electronic extension of the classic hazard warning lights is achieved. An essential component of the device is a radio mode that allows the direct exchange of data between vehicles in real time and with a sufficiently long range, about 1 km. In addition, the device optionally includes a locating module, with which the position of the vehicle by

Location can be determined. This locating module can be part of a navigation system or coupled with a navigation system. If the locating module coupled to a navigation system or part of the same, the vehicle position can be determined with even greater accuracy, because the measured vehicle position can be mapped to the existing digital map in the navigation system by map matching. As a result, errors in the position determination can be compensated by the locating module.

The data received from the sending vehicle include information about the position of the transmitting vehicle. This position information includes positions determined by a location device and / or a direction lane of the vehicle. A directional lane of the vehicle is formed from the direction of travel and speed of the vehicle at different times. The received position information optionally also includes additional information about previous positions of the sending vehicle. The former positions of the vehicle form a position chain of the vehicle consisting of a series of points to which information about the position of the vehicle is available. In this case, the position chain can be a directional lane and / or a sequence of positions determined by means of a positioning system or navigation system.

In an advantageous embodiment of the invention, a relevance measure is determined from the received data of the transmitting vehicle and the position, speed and heading data of the receiving vehicle, is expressed by the probability with which the transmitting vehicle on the front, ie downstream, the Receiver lying section of the track is located. Advantageously, the receiving vehicle has route information with which the future route of the receiving vehicle is estimated. Advantageously, the relevance measure is determined from the received data of the transmitting vehicle and the predicted future driving route of the receiving vehicle, which expresses the probability with which the transmitting vehicle is located on the predicted future driving route of the receiving vehicle. In an advantageous embodiment of the invention, false warnings are recognized based on the time profile of the relevance measure. The information output advantageously takes place as a function of the determined relevance measure. This means, for example, that information whose relevance is too low is not output.

In an advantageous development of the invention, the information output to the driver is terminated as soon as a warning is recognized as false warning. In this case, it is advantageous if the driver, as soon as an information output is terminated due to a false warning, is informed explicitly by an immediately following information output that the previously reported danger is not relevant for him.

In an advantageous embodiment of the invention, the device for radio-based hazard warning includes a data transmitting device, the z. B. is triggered by the hazard warning lights of the vehicle. If the hazard warning system of a vehicle is triggered in this embodiment of the invention, then a corresponding radio message is broadcast to all vehicles in the vicinity of the transmitting vehicle. The transmitted data of each transmitter include its current speed, its position chain and a type of hazard. In one embodiment of the invention, it is also possible for the transmitter to transmit its identification number.

In an advantageous development of the invention, information about the degree of urgency is output by a voice output. In a particularly advantageous embodiment According to the invention, in a method, in particular in a warning warning display method, information about a degree of urgency is output only through a voice output and / or through a one-time voice output. In the display method, depending on the urgency, one of a plurality of predetermined display modes is selected, which includes at least one voice output and another display type.

The realization of different speech outputs to distinguish between different levels of urgency combined with an additional display type, for example an optical and / or a haptic display, has the advantage that the corresponding speech output already contains the important information without the driver having to query another source of information, for example, without having to read a display unit for displaying an optical display. The additional visual display serves only as an optical information storage, to which the driver when needed to refresh the information. This minimizes a distraction effect and increases the clarity of the warnings and the acceptance of the system.

According to an advantageous embodiment of the invention, the speech output may include a distance indication indicating the approximate distance to the source of danger for a determined first urgency level with a low degree of urgency. The distance indication signals to the driver that he still has enough time to reduce his speed by accelerating and possibly braking slightly.

If a second urgency level with a high degree of urgency has been determined, a warning message can be output to the driver, which signals to him that a quick reaction is required and the driver has to implement a braking deceleration which may also lie outside the normal driving comfort range.

At both levels of urgency, the speech output is for the purpose of minimizing the distracting effect. The different levels of urgency are conveyed by the various contents or formulations of the speech output.

In an alternative embodiment of the invention, at least one of the display modes may include a one-time speech output that warns of the danger and includes information about the determined urgency. The only one-time speech output further reduces the distraction of the driver.

In addition to the information on the urgency degree of the hazard warning, information about a danger type can be displayed, for example, via an optical display and / or via the voice output in both emergency levels.

To determine urgency, e.g. external data received from other vehicles or from a central office and evaluated. Alternatively or additionally, data from vehicle sensors may also be evaluated, which may also include a positioning system with a digital map and / or a navigation system.

For carrying out the display method, the display device according to the invention comprises a control / evaluation unit, a voice output unit with specific functionality and a further display unit.

In addition, a data receiving unit and / or a vehicle-side sensor unit may be provided which, for example, provide the control / evaluation unit with data for determining the urgency and / or the distance to the danger spot. The data reception unit can also be used to evaluate external data, for example, from other vehicles or from a control center.

Preferred embodiments of the invention will be described below with reference to the accompanying drawings.

Fig. 1

Ein Blockdiagramm einer Vorrichtung zur funkbasierten Gefahrenwarnung,

Fig. 2

ein Diagramm mit Dringlichkeitsstufen,

Fig. 3

eine beispielhafte Informationsausgabe und

Fig. 4

ein weiteres Beispiel einer Informationsausgabe

Fig. 5

ein Flussdiagramm eines Anzeigeverfahrens zur Gefahrenwarnung in einem Kraftfahrzeug; und

Fig. 6

ein schematisches Blockdiagramm einer Anzeigevorrichtung zur Gefahrenwarnung in einem Kraftfahrzeug.

Showing:

Fig. 1

A block diagram of a radio-based hazard warning device,

Fig. 2

a diagram with urgency levels,

Fig. 3

an exemplary information release and

Fig. 4

another example of an information release

Fig. 5

a flowchart of a display method for hazard warning in a motor vehicle; and

Fig. 6

a schematic block diagram of a warning device in a motor vehicle.

In the figures, like reference numerals are used for corresponding elements.

As can be seen from FIG. 1, the radio-based hazard warning device comprises a data reception unit 10, data transmission unit 15 and a computer unit 20. Preferably, the radio-based hazard warning device is provided with a navigation system 30, an output unit 40, an activation device 50 and a sensor unit 60 Vehicle bus system connected. The sensor unit may comprise a plurality of different sensors, in particular a crash sensor, a speed sensor, etc. The activation device 50 may, for. B. be the hazard warning lights of the vehicle.

The urgency level of a warning is determined when first receiving a radio message when processing the radio message in the computer 20. There may be one or more levels of urgency. The value pairs of distance and approach speed, which belong to a certain level of urgency, can be described, for example, by the fact that the reaction time granted to the driver and the braking deceleration with which he must brake his vehicle in order to prevent it from approaching the transmitter are between common upper limits and lower thresholds. The lower the reaction time and the greater the deceleration, the higher the urgency level. By way of example, urgency levels 0, 1, 2, 3, 4 are shown schematically in FIG. 2 in a diagram.

A warning is only triggered if the approach speed is sufficiently high. If the sender and receiver travel at almost the same speed and constant distance one behind the other, or if the sender even moves away from the receiver, then the sender is no danger to the following receiver and can waive a warning become. This corresponds to the priority level 0 in the diagram of FIG. 2.

Once a priority level has been set, it will be retained as long as further radio messages from the same station are received. Thus, the urgency level of the warning when approaching the danger point is not increased even if the driver does not reduce his speed. The main reason for this is that it is not known which specific danger emanates from the sending vehicle or is marked by it. For example, it makes a big difference whether the sending vehicle is on or off the lane. This information is not necessarily available. Therefore, the driver is much better able than the radio warning system to draw conclusions about the dangerousness of the situation by observing his traffic environment. If the driver sees no danger to himself and his vehicle, then he will continue despite the warning with almost unchanged speed. It can not be concluded from this behavior, however, that the driver did not perceive the warning.

Moreover, in a radio warning system, the time at which a radio message is received from a preceding vehicle can not be foreseen, and also the distance to this vehicle becomes known only upon receipt of the first radio message. Therefore, it may happen that the receiver is already very close to the transmitter when first receiving a radio message and there is only a little time left. In particular, the time may be too short to go through several warning levels of increasing urgency in turn.

By the device for warning the driver should be prompted by the warning mainly to continue with increased attention and watch his traffic environment, since the danger of a situation u. U. from the received danger message is insufficient to remove. If the driver does not detect a specific hazard for him, he will continue despite the warning with almost unchanged speed. This behavior then requires no second, more urgent warning of the hazard warning device.

Advantageously, the driver is warned as long as radio messages are received and the transmitter is located in front of the receiver. It should be noted, however, that external influences can lead to temporary disruptions of the communication connection. Therefore, in the device described here, a failure of further radio messages is initially interpreted as a temporary interruption of the communication link and not as switching off the transmitter. The warning is maintained and the relative motion of the receiver with respect to the transmitter is updated assuming that the transmitter is moving at its last known speed. Only when no more radio messages are received for a sufficiently long time, the warning is terminated, but at the earliest after a minimum warning time, which ensures that the driver can also perceive the displayed warning.

A warning is also terminated when the driver of the receiver indicates by switching on his own hazard warning lights that he has detected the reported hazard. Advantageously, the switch-on of the hazard warning lights and not the state "warning lights on" is used as a criterion for stopping the warning, because otherwise the driver would receive no warning when he approaches a transmitter with already switched hazard warning lights, because he, for example, another vehicle towing. Turning on your own hazard warning lights is an advantageous way for the driver to acknowledge a warning and thus stop it manually. By limiting this type of Acknowledgment, the system remains simple. Further operating actions are conceivable.

A warning is automatically terminated even if the approach speed of the receiver to the transmitter or the absolute speed of the receiver become very small. This prevents that e.g. a display in the vehicle is unnecessarily blocked for a long time.

Scenarios are conceivable, for example when approaching a jam end, where several transmitters simultaneously emit radio messages.

In the system described here, the radio messages of any number of transmitters can be processed in parallel. In this case, successive radio messages of the same transmitter are recognized by their common identification number. First, it is individually checked for each transmitter whether a warning must be issued and which priority level is assigned to it. Then, for the one warning to be issued to the driver, the level of urgency and the type of hazard are set independently of each other.

For the hazard types, a distinction is made between a general hazard, a virtual warning triangle, an accident and a construction site. The danger type general danger is sent when the driver has triggered the hazard warning lights manually and the engine of the vehicle is running, eg when approaching a jam end. The type of hazard virtual warning triangle is sent when the driver has triggered the hazard warning lights manually and the engine of the vehicle is off, for example because the vehicle has a breakdown. The accident type is sent when the hazard warning lights have been triggered automatically by the crash sensor of the vehicle. And the type of construction site is not sent by vehicles, but by beacons that mark the beginning of a construction site.

For the warning to be issued to the driver, the highest of all the urgency levels determined from the received data is used. If the radio messages of different transmitters relate to different types of risk, these are prioritized. For example, the risk type "accident" receives the highest priority. The priority order is then in descending order, for example, accident, general danger, virtual warning triangle and construction site. For the warning to be given to the driver, the highest priority is selected from all existing hazard types.

How to generate a single warning from different radio messages will be explained by the following example. At a distance of 800 meters in front of the receiving vehicle an accident has occurred. In a participating vehicle of the crash sensor was triggered, which in turn has automatically activated the hazard warning lights and thus the transmission function of the radio warning system. The accident vehicle sends the type of accident. A traffic jam forms in front of the scene of the accident. A subsequent vehicle, which is 500 meters in front of the receiver, approaches the end of the jam. The driver triggers the hazard warning lights manually. This vehicle sends the danger type general danger. In the receiving vehicle, the urgency level of the warning is now determined for both transmitters. Since the distance to the vehicle approaching the tail end is much smaller, its warning is assigned a higher level of urgency than the warning of the crashed vehicle. At the same time, the accident type has priority over the type of danger general danger. As a result, the driver is warned of an accident with high urgency, which accurately describes the actual danger situation.

Advantageously, the information about the position transmitted by a sending vehicle comprises a directional lane of the vehicle, formed from the direction of travel and speed of the vehicle at different times. Alternatively or additionally, the information about the position generated by a navigation system 30, this is advantageously done using a location device, for. B. GPS. The road type and the direction of travel can also be determined using a navigation system 30. The determination of position, road type and direction by means of a navigation system 30 is in WO 01/61668 A1 and is incorporated herein by reference. The determination of position, road type and direction using directional lanes of vehicles is in EP 0 927 983 A2 and is incorporated herein by reference.

A position chain of a vehicle consists of a sequence of points for which information about the position of the vehicle is available. In this case, the position chain may be a directional lane and / or a sequence of positions determined by means of location system or navigation system 30. The position chain describes the geometry of the route traveled by the transmitter in the recent past. By comparing its own chain of positions with the transmitter's position chain, the receiving vehicle, the receiver, can check whether the routes traveled by both vehicles are identical and whether the transmitting vehicle, the transmitter, is ahead, ie downstream, or behind, ie upstream, the receiving vehicle, the receiver is located. The result of this comparison is expressed by a measure of relevance. For example, it can be recognized on motorways whether the transmitter is on the same lane in front of the receiver or on the opposite lane. If the sending vehicle is in front of the receiving vehicle on the same lane, the relevance measure is large and the driver of the receiver must be warned of the reported danger. If the sending vehicle is behind the receiving vehicle or on the opposite lane, then the relevance measure is small and the received danger message has no meaning for the driver of the receiver.

Another advantage of the triggering concept described here is the detection of false alarms. A false warning is a warning that warns the driver of a hazard that is not on his future route. There are situations in which a false warning can not be avoided. For example, if the transmitter is just behind a fork in the road, eg on the left branch, then the driver of the receiver must be warned in good time of the reported danger, even if the warning is not yet known, if the receiver is on the left or right branch of the fork will drive. Regardless of the future turn decision, the relevance measure of the transmitter is sufficiently large to trigger a warning. However, after reaching the crotch, the further course of the relevance measure depends on whether the receiver travels the left or right branch of the crotch. In the first case, the position chains of sender and receiver still agree well, the relevance measure remains high and the warning is maintained. In the second case, the position chains of transmitter and receiver diverge and the relevance measure decreases. If it falls below a certain threshold, then it can be assumed that transmitter and receiver are now on different routes and the warning was triggered by mistake. Due to the falling edge of the relevance measure, a false message is therefore detected. If this is the case, then not only the warning is terminated, but the driver is also explicitly informed that the previously reported risk is no longer relevant for him now. This prevents the driver from losing confidence in the radio warning system due to false warnings, which may be unavoidable, or wondering about the apparently groundless disappearance of the warning.

The triggering concept can still be refined by route information that can be taken, for example, a digital road map. On the one hand, with the route information, the future route of the transmitter can be predicted at least until the next crossing point. Thus, the position chain of the transmitter can be extended and the reliability of the relevance measure, which depends on the overlap length of the position chains of transmitter and receiver, can be increased. In addition, with the route forecast, the distance between transmitter and receiver can be more accurately determined because the exact geometry of the track part lying between the two vehicles is known. Likewise, in certain situations false warnings can be avoided by the route information. For example, if it is detected that a transmitter is behind a fork, then only high-priority warning stages can be allowed, thereby ensuring that the distance threshold for triggering the warning is behind the fork and thus allowing the receiver to wait after the fork travels the same branch as the transmitter or the other route alternative chooses.

In an advantageous embodiment of the invention, the triggering concept is supplemented by an output concept. The output concept determines how the driver is warned. There is a close link between the urgency level of a warning, which is determined by the triggering concept, and the type of output. The driver can visually and / or acoustically informed about the danger ahead.

The optical output takes place via a vehicle-mounted display 70. This is preferably integrated into the instrument cluster and thus located in the primary field of view of the driver. There, with an optical output, the attention of the driver can be advantageously directed to the hazard warning. The display area of the display is in different areas 80, 90, 100, 110, 120 divided, which can be controlled individually, pass various information to the driver and activated or hidden depending on the urgency level of the warning.

For warnings associated with a low level of urgency, such as priority level 1, the display configuration in FIG. 3 is used, for example. Symbol A in area 80 is a warning symbol that signals the driver that he should continue with increased attention and caution. This symbol can be the same for all hazard types. However, hazard type specific symbols can also be used. Symbol B in area 90 signals to the driver that the hazard warning has been sent by a preceding vehicle. This information is important to make clear to the driver that the danger has not been detected on board and therefore he can not assume that he will be warned of any comparable danger. The text C in area 100 also informs the driver of the nature of the danger ahead, ie the type of hazard, e.g. Accident.

For warnings associated with a high level of urgency, for example, the display configuration shown in FIG. 4 is used. Again, the symbols A and B are displayed, however, the two display areas 110, 120 provided for the symbols completely fill the display area and the text output is dispensed with. The larger icons allow the driver's attention to be directed even faster to the display or warning. For urgent warnings u. U. anyway in the short time to reach the transmitter the time to read a text information.

In a further embodiment of the output concept, the symbols of FIG. 3 or FIG Warn also for a certain time together or separately from each other flashing, so that the driver can recognize the visual warning even faster and different from other displays on the display better.

The visual warnings can still be supplemented by acoustic signals or voice outputs to ensure a safe perception of the warning even when the driver's gaze away from the instrument cluster, for example, because he operated or mounted in the center console radio or other control device fully focused on the observation of the traffic environment. In turn, different acoustic levels are assigned to different urgency levels so that the driver can immediately recognize their urgency on the basis of the acoustic warning.

In this output concept is advantageous that can be dispensed with the direct output of the distance to the transmitter. In general, the position measurements of sender and receiver are faulty, and the exact geometry of the lying between two vehicles section may not be known. Finally, there is also evidence that drivers misjudge numerically specified distances, which calls into question the usefulness of a numerical distance indication.

Rather, in the described output concept there is a close relationship between the type of optical and acoustic output and the temporal proximity to the transmitter or the necessary driver reaction. This ensures that the driver can react quickly and intuitively to the warning and the driver reaction is not delayed by the tedious and a high distraction effect recording textual and numerical information.

FIGS. 5 and 6 show a further advantageous embodiment of the display concept, which comprises a display method and a display device.

In the danger warning display method illustrated in FIG. 5, in a first step 5.100, an urgency of the hazard warning to be displayed is determined. In a next step 5,200, one of several display modes is selected depending on the determined urgency level. If a first urgency level with a low urgency level is determined, a first display mode (step 5.300) is selected, and then a one-time speech and another type of display are activated in step 5.350 to warn of the danger, with only the speech output containing urgency level information. The further type of display is, for example, an optical and / or haptic display. In the illustrated embodiment, an additional visual indication is activated and the low degree of urgency is represented by the one-time speech output of the distance to the danger location.

At a determined second level of urgency with a high, i. A second display mode (step 5400) is selected in relation to the above low degree of urgency and then, in step 5.450, a one-time speech display and another display type are activated in the form of an optical display warning of the danger, wherein only the speech output contains information about the speech Urgency level includes. In the illustrated embodiment, the high degree of urgency is represented by the one-time speech output of a warning.

At the first emergency level and the associated selected first display mode, the driver is informed by voice once about the type of danger and the distance to the danger point, eg "traffic jam at 700 meters" or "accident in 600 meters. "The visual display includes a warning symbol with an additional text that also describes the danger, eg" traffic jam "or" accident. "The first priority level has a more informative character the voice output takes place and does not appear visually.

This approach is based on the knowledge that drivers are accustomed on the one hand from their everyday experience to dealing with specific distance information, for example by distance indications on traffic signs, but on the other hand can only estimate distances with difficulty. Since the speech output includes the usual and therefore expected distance indication, the acceptance of the display method increases. The driver has the impression that he has received all relevant information. At the same time it is ensured by the only one-time acoustic distance indication that the driver is only given a qualitative impression of the distance to the danger spot. This feature is important because the exact distance to the danger point can not usually be determined and therefore the driver must not rely on the distance indication. Therefore, it is avoided in the present case to update the distance indication acoustically or to display it continuously on a display.

At the second level of urgency and the associated selected second display mode, the voice prompt of a warning message directly prompts the driver to be cautious and drive on with high attention. He is also informed about the nature of the danger. Examples of the second urgency level voice response warning are "attention, congestion" or "attention, accident". By using the term "attention", the driver is signaled that he must react immediately to the warning, for example, by a rapid and strong braking, possibly even beyond a normal driving comfort range, because the danger spot is immediately in front of him. There is no more speech output with a distance indication. The spatial and temporal proximity of the event is described by the warning "Attention". Also in the case of the second level of urgency, there is an optical display which in the illustrated embodiment is identical to that from the first priority level. This makes it clear that the voice output is the primary information channel through which the urgency of a hazard warning is conveyed. The optical display is only to be seen as a supplement.

In order to determine the urgency, data from a data receiving unit and / or from a sensor unit with a locating unit with a digital map and a navigation system are evaluated in the exemplary embodiment shown.

As can be seen from FIG. 6, the warning device warning device in a motor vehicle shown there comprises a control / evaluation unit 20 for determining a temporal urgency of the hazard warning to be displayed and for selecting one of a plurality of predetermined display modes depending on the degree of urgency determined and a display device 6.3 to display the hazard warning with the selected display mode. The display device 6.3 comprises an optical display unit 6.3.1 and a voice output unit 6.3.2, which warn of the danger in at least one display mode, with only the voice output unit 6.3.2 outputting information about the degree of urgency.

If the control / evaluation unit 20 determines a first urgency level with a low degree of urgency, the visual display unit 6.3.1 and the speech output unit 6.3.2 output an indication of the type of danger, for example "traffic jam" or "accident". The voice output unit 6.3.2 also outputs a distance indication, which corresponds to the approximate distance of the vehicle to the danger spot.

If the control / evaluation unit 20 determines a second urgency level with a high degree of urgency, the visual display unit 6.3.1 and the speech output unit 6.3.2 again display the indication of the type of danger. The voice output unit 6.3.2 also issues a warning that signals that an immediate response is required.

To determine the urgency, the control / evaluation unit 20 evaluates external data received from a data receiving unit 10 from other vehicles and / or from a control center. Alternatively or additionally, data can be evaluated by a vehicle-side sensor unit 5, which includes, for example, sensors of driver assistance systems and / or of a positioning unit with a digital map and / or a navigation system 30.

Claims (7)

1. Method for issuing warnings of hazards to the driver of a vehicle, in which data from at least one other vehicle is received and the received data is evaluated, the received data comprising information about the position, the speed and the direction of travel of the transmitting vehicle, the approach speed between the receiving vehicle and the transmitting vehicle being determined in order to evaluate the received data in the receiving vehicle and the distance between the transmitting vehicle and the receiving vehicle being determined in order to evaluate the received data in the receiving vehicle, characterized in that using the distance between the transmitting vehicle and the receiving vehicle and using the approach speed between the transmitting vehicle and receiving vehicle an urgency level for the outputting of information is determined, information being output to the driver as a function of said urgency level and the urgency level being defined as a function of the time which has passed since information was last output.
2. Method according to Claim 1,
   characterized in that false warnings owing to the time profile of a relevance measure which is determined from the data received from the transmitting vehicle and the position data, speed data and direction of travel data of the receiving vehicle and which specifies the probability of the transmitting vehicle being located downstream on a section of road before the receiving vehicle are recognized.
3. Method according to Claim 1 or 2,
   characterized in that, directly subsequent to a false warning, information is output to the driver to the effect that the previously signalled hazard is not relevant.
4. Method for issuing warnings of hazards to the driver of a vehicle according to Claim 1,
   characterized in that the information output to the driver contains information about the determined degree of urgency.
5. Method for issuing warnings of hazards to the driver of a vehicle according to Claim 4,
   characterized in that the information about the determined degree of urgency (0, 1, 2, 3, 4) comprises a hazard distance information.
6. Method for issuing warnings of hazards to the driver of a vehicle according to Claim 4 or 5,
   characterized in that the information about the determined degree of urgency (0, 1, 2, 3, 4) is conveyed to the driver by voice output.
7. Method for issuing warnings of hazards to the driver of a vehicle according to Claim 6,
   characterized in that the voice output is supplemented by visual displays and/or haptic indications depending on the degree of urgency which is determined.

Images