1. Field of the Invention
The present invention relates to a method for optimizing the provision of a predictive EHORIZON™ (Computer software and hardware for integrating navigational map data with electronic vehicle controls and software for providing driver alerts and control system inputs based upon vehicle parameters and navigational data) in a driver assistance system. In particular, the invention specifies a method suitable for making available an EHORIZON™ (Computer software and hardware for integrating navigational map data with electronic vehicle controls and software for providing driver alerts and control system inputs based upon vehicle parameters and navigational data) with sufficient accuracy in the case of changing available processor power in a driver assistance system.
2. Description of Prior Art
Driver assistance systems such as lane departure warning systems or adaptive cruise control (ACC) are known. Navigation systems are also finding widespread application both in the field of passenger cars and utility vehicles. A new generation of driver assistance systems make available to the driver and/or the vehicle information about the route lying ahead of the vehicle. This information, which is referred to as EHORIZON™ (Computer software and hardware for integrating navigational map data with electronic vehicle controls and software for providing driver alerts and control system inputs based upon vehicle parameters and navigational data), can comprise information about any bend courses, gradients, speed restrictions, or the like. As a result it is possible to inform the driver of hazardous situations clearly before such situations occur. This can lead to an improvement in safety and also to a reduction in the fuel consumption by virtue of the fact that it influences the engine management and/or the shift strategy of an automatic transmission. An EHORIZON™ (Computer software and hardware for integrating navigational map data with electronic vehicle controls and software for providing driver alerts and control system inputs based upon vehicle parameters and navigational data) can therefore transmit information about a bend lying directly ahead or an imminent gradient to an automatic transmission which, on the basis of this information, does not shift correspondingly until later into a higher gear speed and can therefore maintain rotational speed in an optimized range. Such an EHORIZON™ (Computer software and hardware for integrating navigational map data with electronic vehicle controls and software for providing driver alerts and control system inputs based upon vehicle parameters and navigational data) can also influence electrical energy management of a vehicle and also activate or deactivate functions in accordance with the route lying ahead. In an ACC an EHORIZON™ (Computer software and hardware for integrating navigational map data with electronic vehicle controls and software for providing driver alerts and control system inputs based upon vehicle parameters and navigational data) can be used to adapt the acceleration behavior of the vehicle to the course of the road.
In a driver assistance system of the type described above, an EHORIZON™ (Computer software and hardware for integrating navigational map data with electronic vehicle controls and software for providing driver alerts and control system inputs based upon vehicle parameters and navigational data) is provided by a horizon provider that precisely calculates the respective vehicle position based on stored digital maps, GPS information, gyroscope information, and/or wheel speed information, and transmits information continuously about the further course of the road into a BUS system (for example CAN bus) of the vehicle electronics. Further control systems, such as the engine management system, a transmission management system or an ACC, which are connected to this BUS system, build up the virtual picture of the road from the information provided using what is referred to as a reconstructor, and orient their control strategy to the expected course of the road.
To provide an EHORIZON™ (Computer software and hardware for integrating navigational map data with electronic vehicle controls and software for providing driver alerts and control system inputs based upon vehicle parameters and navigational data), the provider checks the position and possibly the route of the vehicle at fixed time intervals, determines the associated map detail of a digital map and the relevant roads, and provides necessary data via the BUS system. Such a procedure is configured for as constant as possible utilization of computing power. This requires a correspondingly large amount of computing power to be made available to ensure a sufficient provision of information of the provider into the BUS system even in situations with increased calculation expenditure such as change of route. This high level of available computing power is not called up and not required in the major part of the operating time.