Abstract:
A method and a driver assistance system for notifying the driver of a motor vehicle about a danger spot are provided. In an embodiment, the method includes providing informational data about the danger spot from a data storage device, providing current image data using a camera, and analyzing a current danger situation by comparing the current image data with the informational data using a central processing unit. A warning signal is outputted to the driver via an output unit depending on the current danger situation.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
       [0001]    This application claims priority to German Patent Application No. 10 2011 018 157.1, filed Apr. 19, 2011, which is incorporated herein by reference in its entirety. 
       TECHNICAL FIELD 
       [0002]    The technical field generally relates to methods for supporting the driver of a vehicle at danger spots, in particular stops for special vehicles, for example public transportation vehicles, as well as to driver assistance systems for implementing the methods. 
       BACKGROUND 
       [0003]    There are numerous known devices for detecting traffic signs, in particular speed limit signs. Cameras are often used for detection. The traffic sign detection system is traditionally used to determine the maximum speed limit and warn the driver when the latter is being exceeded. 
         [0004]    In addition, publication DE 20 2009 010 876 U1 discloses a system for warning road users about an increased danger of accidents at bus stops. It proposes that a bus be equipped with a transmitter, and a receiver be provided with a signal light a distance away from the stop. As the bus approaches the stop, the transmitter on the bus sends information to the receiver, as a function of which the signal lights can be activated to warn trailing traffic. 
         [0005]    This system requires that each bus be equipped with a transmitter, and that each stop be equipped with a receiver and signal light. This makes it complicated and expensive. 
         [0006]    It is at least one object to provide a more cost-effective method with which the driver of a motor vehicle is alerted early on about a danger spot, in particular a stop for public transportation vehicles. In addition, other objects, desirable features and characteristics will become apparent from the subsequent summary and detailed description, and the appended claims, taken in conjunction with the accompanying drawings and this background. 
       SUMMARY 
       [0007]    In this regard, a method for notifying the driver of a motor vehicle before a danger spot, in particular a stop for buses or trams, involves the following steps: 
         [0000]    Providing informational data about a danger spot from a data storage device,
 
Acquiring current image data of the environment ahead by means of a camera,
 
Determining a current danger situation by comparing the current image data with the informational data by means of a central processing unit, and
 
Outputting a warning signal to the driver depending on the current danger situation via an output unit.
 
         [0008]    Since the environment ahead of the motor vehicle is acquired with the camera, the method allows predictive support for the driver. Depending on the range of the camera and the weather conditions, the driver can be provided with an early warning. His or her response time can be shortened as a result. The method thus makes it possible to better protect pedestrians at the danger spot against accidents. 
         [0009]    The camera is preferably arranged in or on the motor vehicle, and pointed forward at the road and/or roadside, so that it can detect primarily traffic signs located on the roadside and persons standing on the roadside. Depending on the alignment and acquisition angle of the camera, several indications can be acquired at the danger spot, for example, the persons crossing the road, the course of the road, or the traffic density. 
         [0010]    It is preferred that the camera for determining the current danger situation use the current image data of an image series. This makes it possible to compensate for obscured indications, for example, as a result of vehicles parking on the roadside or rain or fog, and ensure a high detection rate. 
         [0011]    While a central processing unit compares the current image data with the informational data, the informational data and current image data are preferably present as digital data, thereby enabling a digital image evaluation that permits a very rapid evaluation with a high level of precision. 
         [0012]    The informational data preferably encompass hazard indications, such as traffic sign data, in particular of a bus stop sign, a barricade sign, a stop sign, an intersection or a railway crossing. They preferably also encompass hazard indications such as road progression data, in particular for merging traffic, an intersection, or a bus bay. It is also preferred that the informational data encompass other hazard indications for typical dangers, in particular a traffic light or road inscription. 
         [0013]    In an also preferred embodiment, the informational data encompass contour data for recognizing a special vehicle, in particular a bus and/or a tram. 
         [0014]    It is preferred that the warning signal be output once a current danger situation has been identified and/or indicated, in particular the traffic sign and/or special vehicle. 
         [0015]    It is preferred that the danger situation be weighted as a function of the comparison data acquired by comparing the current image data with the informational data. The response to the danger situation varies in severity depending on the hazard posed to persons in the danger situation. 
         [0016]    In order to enable a weighting of the danger situation, another preferred embodiment provides that the informational data also encompass information for acquiring one or more of the following environmental data: 
         [0000]    Special vehicle has arrived at the danger spot,
 
Persons on the roadside,
 
Persons crossing the road,
 
Magnitude of traffic density,
 
Weather conditions,
 
Distance from adjacent vehicles,
 
Road progression, and/or
 
Current speed of vehicle.
 
         [0017]    It is preferred that at least the warning signal differ as a function of the weighting, and/or that the vehicle be slowed down, and/or that the vehicle even be diverted. 
         [0018]    It is especially preferred that a bus stop or railway stop, for example for a street car, be detected. In an especially preferred embodiment, the informational data encompass at least the traffic sign data for a stop for a special vehicle, in particular a bus or tram. In this embodiment, the informational data preferably encompass additional informational data at the stop and/or informational data for acquiring the bus or tram. 
         [0019]    In addition, a driver assistance system that utilizes the above-described method is provided. The driver assistance system preferably encompasses a camera, a data storage device for storing informational data, a central processing unit for acquiring a danger situation, and an output unit for outputting a warning signal. 
         [0020]    The warning signal is preferably an optical, acoustic and/or haptic signal, wherein the output unit is a light source, in particular an LED, a display, a loudspeaker and/or a steering wheel. However, it is also preferred that the warning signal be or encompass a control signal to an engine management system of a vehicle, which makes it possible to slow down and/or divert the vehicle. 
         [0021]    The driver assistance program is preferably provided for acquiring a stop, in particular for buses or trams. 
     
    
     
       DETAILED DESCRIPTION OF THE DRAWINGS 
         [0022]    The embodiments will hereinafter be described in conjunction with the following drawing figures, wherein like numerals denote like elements, and wherein: 
           [0023]      FIG. 1  shows a road as seen by the driver of a vehicle; and 
           [0024]      FIG. 2  shows a driver assistance system according to an exemplary embodiment. 
       
    
    
     DETAILED DESCRIPTION 
       [0025]    The following detailed description is merely exemplary in nature and is not intended to limit application and uses. Furthermore, there is no intention to be bound by any theory presented in the preceding background or summary or the following detailed description. 
         [0026]      FIG. 1  shows a road  2  as seen by the driver of a vehicle  1 . The vehicle exhibits a driver assistance system  10  according to an exemplary embodiment (see  FIG. 2 ). The driver assistance system  10  encompasses an image processing unit, here a camera, which is arranged in a vehicle interior  11 . The camera cyclically acquires current image data  91  (see  FIG. 2 ) of the environment ahead of the vehicle  1  in the traveling direction  22 , so as to recognize a danger situation at a danger spot  3  as early as possible. 
         [0027]      FIG. 1  shows such a danger situation, in which the danger spot  3  is here a stop. The terms danger spot  3  and stop are used synonymously in the following. 
         [0028]    The stop  3  is here characterized by a bus stop sign  41 . In addition, a ticket machine  42  and road marking  43  of the stop  3  are provided. 
         [0029]    A waiting person  5  is visible on a roadside  21  in the area of the stop  3 . 
         [0030]    Output units  61 - 63  (see also  FIG. 2 ) are provided in a vehicle interior  11 , which can be used to output a warning signal  661 - 663  (see also  FIG. 2 ) in the danger situation. Depicted here as the output units are a light  61 , a display  62  as well as a steering wheel  63  of the vehicle  1 . The light  61  and display  62  can be used for optical warning signals  661 ,  662 , and the steering wheel  63  for a haptic warning signal  663 , for example by vibrating. A modified steering support in a preferred steering direction is further possible. 
         [0031]    Alternatively or additionally, it is conceivable to use a loudspeaker (not shown) as an output unit for an acoustic warning signal. Given a danger situation involving a high hazard level, it is also further preferred that the vehicle be alternatively or additionally slowed down or diverted away from the danger by means of an engine management system  64  (see  FIG. 2 ). 
         [0032]      FIG. 2  shows the driver assistance system  10  according to an embodiment. The driver assistance system  20  encompasses a data storage device  8 , which stores informational data  81  regarding the danger situation. 
         [0033]    For example, such informational data  81  include hazard indications like traffic sign data that enable traffic sign detection. Primarily the traffic signs where a danger situation might exist, for example, a bus stop sign  41  (see  FIG. 1 ), a closed sign, a stop sign, an intersection sign, a railway crossing sign or marking, or combinations thereof, are stored. 
         [0034]    Other examples for informational data  81  include road progression data, which permit the recognition of a merge, a crossing, a curve or a bus bay, or other typical danger-related informational data  81 , e.g., which allow recognition of a traffic light. 
         [0035]    Informational data  81  can also include road markings  43  or road inscriptions, for example an inscription like “TAXI”, which enable the recognition of merges, bus stops or the like, such as merge signs and bus stop signs. 
         [0036]    It is further preferred that contour data for recognizing a “special vehicle”, for example, a bus and/or tram, be used as informational data  81 , which reflect the contour of such a vehicle and enable the recognition of the vehicle. 
         [0037]    It is also conceivable to use the contour of a ticket machine  42  (see  FIG. 1 ) for recognizing the bus stop  3 . 
         [0038]    The informational data preferably also encompass information with which environmental data relating to the danger situation can be acquired. For example, such environmental data make it possible to determined that: 
         [0000]    a “special vehicle,” for example a bus or tram, but potentially a garbage truck or the like as well, has arrived at the danger spot  3 ,
 
one or more persons  5  are waiting on the roadside  21 ,
 
one or more persons  5  are crossing the road  2 
 
and combinations thereof.
 
         [0039]    Such additional informational data also make it possible to acquire: 
         [0000]    the magnitude of traffic density,
 
the distance and/or relative speed of the vehicle  1  in relation to adjacent vehicles,
 
the road progression,
 
the current speed of the vehicle  1 , or
 
combinations thereof.
 
         [0040]    These additional informational data enable or improve a weighting of the danger situation, so that the warning signal  661 - 664  can be changed as a function of the weighting, i.e., the ascertained level of danger. The intensity and/or duration of the warning signal  661 - 664  is here varied depending on the weighting of the danger situation. In a danger situation that poses very little or no danger to third parties  5  and the vehicle  1 , it is preferred that no warning signal  661 - 664  be output. Given a very acute danger situation, it is preferred that a continuous and strong, for example loud or bright, warning signal  661 - 664  be output, or that the vehicle  1  even be slowed down or diverted. 
         [0041]    The driver assistance system  10  provides for a camera  9  for acquiring current image data, which acquires the environment ahead in the traveling direction  22 . By comparing the informational data with the current image data, a danger situation is acquired when hazard indications are present. To this end, the driver assistance system  10  provides for a central processing unit  7 . For example, a danger situation is present if a specific traffic sign was acquired, and/or if a bus stop was acquired, and/or if a special vehicle was acquired. 
         [0042]    The central processing unit  7  is also provided for controlling the driver assistance system  10 , and thus generates a warning signal  661 - 664  depending on the weighting of the danger situation. 
         [0043]    For example, a steering wheel  63  is here provided as the output unit  61 - 64  for the warning signal  661 - 664 , and enables a haptic warning by vibrating. In addition, for example, a light  61  and a display  62  for optical warnings are provided here. It is further provided that the warning signal  664  be transmitted to the engine management system  64 , so as to even slow down the vehicle  1  or divert it from the danger. 
         [0044]    In the exemplary embodiment on  FIG. 1 , the danger situation is primarily recognized based on the stop sign  41 , but also based on the road machine  42  and road marking  43 . The driver assistance system  10  according to an embodiment also recognizes a present hazard posed by a person  5  waiting on the roadside  21 , and weights the danger situation accordingly. For example, the light  61  here outputs a warning light indicating the bus stop. 
         [0045]    While at least one exemplary embodiment has been presented in the foregoing detailed description, it should be appreciated that a vast number of variations exist. It should also be appreciated that the exemplary embodiment or exemplary embodiments are only examples, and are not intended to limit the scope, applicability, or configuration of the invention in any way. Rather, the foregoing detailed description will provide those skilled in the art with a convenient road map for implementing an exemplary embodiment, it being understood that various changes may be made in the function and arrangement of elements described in an exemplary embodiment without departing from the scope of the invention as set forth in the appended claims and their legal equivalents.