WO2008122367A1

WO2008122367A1 - Method for representing a weather event and display system

Info

Publication number: WO2008122367A1
Application number: PCT/EP2008/002404
Authority: WO
Inventors: Georg Obert
Original assignee: Bayerische Motoren Werke Aktiengesellschaft
Priority date: 2007-04-10
Filing date: 2008-03-27
Publication date: 2008-10-16
Also published as: DE102007016978A1; EP2135036A1

Abstract

The invention relates to a method for representing a weather event. In said method, on the basis of a vector-oriented electronic road map, part of a road map is reproduced on a display unit and a weather event object comprising a weather code, area description object and reference co-ordinates is received. The weather event is then represented on the display unit, on the basis of the weather event object, as an overlaid area on the road map.

Description

METHOD FOR PRESENTING A WEATHER EVENT AND

DISPLAY SYSTEM

The invention relates to a method for displaying a weather event and a corresponding display system.

From EP 0798540 A1 a method for referencing stationary objects on the earth's surface by assigning a unique code is known. This procedure includes the following steps:

- It is defined a grid with a given resolution (mesh size) and a predetermined position with respect to the earth's surface, the nodes of the grid are converted by a first reversible computing rule in a geographic coordinate system.

- The objects are uniquely mapped to the nodes of the grid.

- The nodes of the grid is uniquely assigned a code by a second reversible calculation rule.

- The identified object of the identified code of the associated node is assigned.

This should overcome compatibility problems with the least possible effort.

From DE 10139668 A1 a method for generating route-related weather and / or road condition information for a vehicle is known. In this case, the weather forecast data and data relating to the actual weather-related conditions in the surroundings of the motor vehicle are recorded by a central unit and informed on a display in the field of vision of the driver about the actual weather or the road condition along the travel route. In addition, the display of weather information on screens using a browser is known. An image is prepared by a service provider by providing it with a geographical reference (usually outline of the land mass with representation of national borders) and is brought into a digitally processable image format (GIF, JPEG, TIFF), which is then transmitted via communication media and displayed with the help of a browser. The representation of a weather situation or weather events by such a pixel-based image but has the disadvantage that no Ortsreferenzierung to a digital road map is present so that no assignment to a representation of an electronic road map is possible, and therefore a separate presentation must be made. Even when using different magnification levels, either an image has to be reloaded or one is content with a coarse pixel representation or with certain sections the loss of geo-referenced features for orientation.

The invention is therefore based on the object of specifying a technical teaching with which, in particular, the driver of a motor vehicle can be comprehensively and easily informed about location-dependent weather events.

This object is solved by the features of the independent claims. Advantageous developments of the invention can be found in the dependent claims. In the context of the invention are also developments of the independent system claim that correspond to the dependent method claims.

In a method according to the invention for displaying a weather event, a part of a road map is displayed on a display device based on a vector-oriented electronic road map. A weather event object is received that includes a weather code, a surface description object, and reference coordinates. The area description object may describe the size, orientation, and / or shape of the area by, for example, indicating coordinates of further corners or edge points of a geometric shape, or by specifying vectors that describe a geometric shape or traverse based on the reference coordinates.

The weather event is then displayed on the display device based on the weather event object as a surface superimposed on the illustrated road map, in particular transparent or semitransparent.

By the invention it is achieved that simultaneously with the representation of a vector-based road map, in particular superimposed on this, a weather event can be displayed in the right place relative to this road map. As a result, a driver can be detected quickly and reliably informed about a current or predicted weather event with regard to the situation.

If appropriate, size information contained in the area description object is still adapted to the currently set zoom factor of the representation of the road map in order to reliably inform the driver also with regard to the size of a current or predicted weather event.

Preferably, the vector-oriented electronic road map is based on nodes or edges or is described thereby, wherein the nodes are each assigned the coordinates of a defined coordinate system. Since the reference coordinates can also be described or described by coordinates of the defined coordinate system (if necessary after a corresponding conversion), the areal weather forecast can be described or described. Position can be assigned to the correct location or the correct node of the road map and so in relation to the road map displayed in the right place.

According to a preferred embodiment of the invention, the location of the area relative to the road map is determined based on at least one node of the road map and the reference coordinates, for example by assigning the reference coordinates to the node closest to the coordinate system or by locating the reference coordinates relative to two nearby nodes of the road map is determined by interpolation or extrapolation.

The above object is also achieved by a display system having a display device for displaying at least a part of a road map based on a vector-oriented electronic road map, with a receiving device for receiving a weather event object comprising a weather code, a surface description object and reference coordinates, and with a processor device , which is set up such that, based on the weather event object, the weather event is displayed on the display device as the area superimposed on the road map shown.

In the following, the invention is explained in more detail by means of examples with reference to the following figures:

FIG. 1 shows a simplified flow diagram for the representation of a

Weather event;

FIG. 2 shows a representation of a two-dimensional weather event; FIGS. 3-6 show variants for describing a two-dimensional weather event.

As shown in FIG. 1, in a content provider CP weather information is summarized based on corresponding measurements and provided in a suitable form:

a) Weather data in GRID format (gridded binary), which includes georeferencing. b) Cloud images of satellites that have a (cartographic) graphical reference to the Earth's surface. c) Precipitation zones based on a weather radar, which have a (karto) graphical and local reference (coordinates of the radar station).

At a service provider SP, these weather information are processed in such a way that they can be displayed by a navigation system in the correct location.

For this purpose, a planar weather event is converted into one or more weather event objects, each comprising a weather code, a surface description object and reference coordinates (for example, a reference coordinate pair, which may also be referred to as a reference coordinate) in WGS84 coordinates.

The area description object indicates the size, orientation, and / or shape of an area within which the corresponding weather event occurs. The surface can be defined by WGS-84 coordinates of other corners or boundary points of a geometric shape or by vectors (described ben by suitable WGS-84 coordinates), which describe a geometric shape or a polygon starting from the reference coordinates. In particular, the area description object is likewise described vector-oriented.

The weather event object is transmitted, for example, in the context of a broadcast, multicast or unicast system to one or more vehicles, in particular vehicle navigation systems F, and stored there in a memory device.

In a memory device (map data memory) assigned to the vehicle navigation systems F, a vector-oriented digital road map is stored, which can be displayed in sections with different scales on a display device.

In this case, "vector-oriented" means that the electronic road map is based on nodes and edges, wherein the nodes are each defined by WGS84 coordinates. In particular, lines or curves are defined by a starting point, possibly several intermediate points and an end point, and the line thickness. The link or edge between these points is then calculated by a graphics program and gives, for example, a road to be displayed. In areas next to the line also the type of filling is defined. In contrast to a bitmap or pixel graphic, a vector graphic can be scaled down or enlarged without loss of quality.

On the display of the navigation system based on the weather event object, the weather event is displayed as the superimposed surface of the road map shown. For this purpose, the location of the area is determined based on the road map based on at least one node of the road map and the reference coordinate. In addition, the size and shape of the Area determined by the location of the remaining vertices transmitted with the area description object. For this purpose, the position of these corner points relative to the road map is likewise determined based on at least one node of the road map and the corresponding coordinates of the corner point. As a result, the surface is anchored on the vector-oriented road map or the road map läge- and size correctly assigned, so that the representation of the area together with the representation of the road map is freely scalable and displayed accordingly.

Figure 2 shows the representation of a road map SK with a superimposed representation of two different weather events ("rain", "heavy rain") with corresponding vertices (numbers 1 to 10 and 1 to 9). The weather event WE "rain" is represented by a larger area, which is superimposed on the road map representation substantially transparent. By way of example, the reference coordinates RK of this area are also shown. The weather event "Heavy Rain" is represented by a smaller area, which is essentially not transparently superimposed on the road map display.

FIG. 3 shows a rectangle which, starting from the reference coordinates RK, is spanned by two vectors of length a and b. One or more such rectangles may describe the area of a weather event.

FIG. 4 shows an ellipse which, starting from the reference coordinates, is determined by two vectors of length a and b. One or more of such ellipses may also describe the area of a weather event.

Figure 5 shows a plurality of tiles of the same size, shape and orientation, by starting from the reference coordinates by the indication Further coordinate pairs (0.0, 0.1, 1, -1, ...) the surface of a weather event can be described.

FIG. 6 shows, starting from the reference coordinates, a polygon whose vertices can each be described by a vector. By such a polygon, the area of a weather event can also be described.

Claims

claims

1. A method for displaying a weather event

in which a part of a road map (SK) is displayed on a display device based on a vector-oriented electronic road map,

- in which a weather event object is received, which comprises a weather code, a surface description object (a, b) and reference coordinates (RK), and

- In which on the display device based on the weather event object, the weather event as the road map (SK) superimposed area (WE) is displayed.

2. The method of claim 1, wherein the vector-oriented electronic road map is based on nodes and edges, where nodes are each associated with the coordinates of a defined coordinate system.

3. The method according to any one of the preceding claims, wherein the reference coordinates (RK) is described or described by coordinates of the defined coordinate system, and wherein the position of the surface (WE) relative to the road map based on at least one node of the road map and the reference coordinates (RK) is determined.

4. Display system with a display device for displaying at least part of a road map (SK) based on a vector-oriented electronic road map, with a receiving device for receiving a weather event object, which comprises a weather code, a surface description object and reference coordinates (RK), and with a processor device which is set up such that based on the weather event object the weather event is superimposed on the display device as the road map shown is pictured.