WO2004003477A1

WO2004003477A1 - Method for displaying a map

Info

Publication number: WO2004003477A1
Application number: PCT/EP2003/006792
Authority: WO
Inventors: Elmar Cochlovius; Oliver Wagner
Original assignee: Harman Becker Automotive Systems Gmbh
Priority date: 2002-06-27
Filing date: 2003-06-26
Publication date: 2004-01-08
Also published as: DE10228724A1; AU2003246606A1

Abstract

With a method for presentation of a map on a display device of a map presentation system for a vehicle, the map is displayed initially in a first scale. Then a second scale differing from the first scale is defined. At least one interim scale is determined from the first and the second scale. Starting from the first scale, the map is firstly displayed in at least this one interim scale and only afterwards in the second scale.

Description

METHOD FOR DISPLAYING A MAP

The invention relates to a method for the presentation of a map on a display device of a map presentation system for a vehicle, whereby the map is initially presented in a first scale, whereby a second scale differing from the first scale is defined and the map is then displayed in the second scale.

A method of this type for the presentation of a road map is known from DE 100 27 516 A1. Here, the scale or the zoom factor in which the map is displayed on the display device of the map presentation system is calculated in each case depending on data present in the map presentation system, namely point of interest data, distance data and measurement values for the vehicle speed in question. After this, the map is presented with the calculated scale on the display device in order to show the user of the map presentation system a section of the map adjusted to the relevant operating situation of the vehicle. The method therefore works with a variable zoom factor, by which means, according to the published patent application, there is no need for the vehicle user to intervene directly in the zoom setting.

The method has the disadvantage, however, that a rapid change in the vehicle speed may cause a sudden change in the scale used for the map presentation at the time. The resultant violent change from the old to the new map section means that the vehicle driver requires a certain adaptation period to orient himself in the new map section. This may cause confusion and lack of attention on the part of the driver.

From DE 100 27 516 A1 , we are also already familiar with a method of the type mentioned at the beginning in which the vehicle user selects the right scale himself. A map presentation system known from practice which works using this method has a +/- key for setting the scale, with which the user can enlarge or reduce the scale by one increment in each case. It is not possible to directly select the scale or zoom factor, but the user can instead bring the set scale closer to the scale required in each case by repeatedly operating the +/- key. This method is also unsatisfactory, since, to give a sufficiently infinitely variable change in the map section, the +/- steps would have to be very fine, which means that operation would be correspondingly tiresome. In addition, the user has to keep the display device constantly in view in order to be able to monitor whether the required zoom factor has been reached.

The object of the invention is therefore to create a method of the type described at the beginning which allows the user of the map presentation system to orient himself quickly and easily after the scale of the map has been changed.

This task is solved by the fact that at least one interim scale is determined from the first and the second scale and that the map, after being presented in the first scale, is displayed initially in at least this one interim scale and only afterwards in the second scale.

Advantageously, therefore, the desired scale change is carried out via at least one interim stage, rather than suddenly. This creates, for the user of the map presentation system, the impression of a gradual transition from the map presentation in the first scale to the map presentation in the second scale. This allows him to follow important map contents with the eye and to find them again immediately in the map presentation in the second scale. The driver of the vehicle can thus orientate himself quickly and easily in the map after a scale change. The driver is less distracted from the road traffic and road safety is increased.

In an advantageous embodiment of the invention, a series of several interim scales is determined from the first and the second scale in such a way that these interim scales starting from a first interim scale, which is to be set first, to a last interim scale, which is to be set last, approach the second scale and then the map is displayed in these interim scales one after the other. The transition from the first to the second scale is therefore carried out via a sequence of several interim scales, with this sequence preferably being carried out so quickly that the user has the impression of a continuous scale change. In this way, the contents of the map can be followed even more easily by the eye.

It is an advantage if the individual interim scales in the series are selected in such a way that they bridge the difference between the first and the second scale in steps of equal sizes. This measure creates a particularly gentle transition from the map presentation in the first scale to the map presentation in the second scale.

In a practical embodiment of the invention, directly consecutive points in time in which a new interim scale or a new scale of the map presentation is set have roughly constant time differences between them. This measure can also produce a particularly gentle transition of the map presentation in the first scale to the map presentation in the second scale.

It is particularly advantageous if, when determining a new scale during the presentation of the map in an interim scale, a new interim scale or a new series of interim scales is determined from the currently set interim scale as the new first scale and the scale to be set as the new second scale and if the map is then shown afterwards in the new interim scale or the new series of interim scales. This avoids overlapping sequences of interim steps. In addition, the map presentation is quickly modified to the desired new scale.

In a preferred embodiment of the method, whilst the map is presented in an interim scale, data for a map presentation to be displayed at a later time are loaded from a map data memory into a working memory of a control device of the display device. Advantageously, this allows a look-ahead strategy to be implemented for the requesting of required map data which can be loaded for example from a navigation device into the control device. The working memory of the control device does not contain all map data, but rather only the information that is required for the map representation in the first scale and in slightly differing interim scales. If the data required for the presentation of the map in further interim scales and/or in the second scale are not available, they can be requested immediately. The waiting time required to load these data can be logically bridged with the map presentations in the interim scales in a way that is not noticeable to the user.

In an advantageous embodiment of the invention, the first and/or second scale is determined as a function of at least one operating parameter of the vehicle and the operating parameter is, in particular, the vehicle speed. This then produces a fully automatic zoom factor setting which means that the strain on the user of the map presentation system is even less.

The first and/or second scale can, however, also be determined as a function of an entry made by a user of the map presentation system. Once again, the invention allows the user of the map presentation system to follow important map contents with the eye and to orient himself again immediately after the change from the first to the second scale.

In the following, an embodiment of the invention is explained in more detail on the basis of the drawing. It shows:

Fig. 1 a schematic representation of the components of a navigation system with a map presentation system,

Fig. 2 a graphic representation showing a sequence of reproductions of a road map shown on a display device of a map presentation system, whereby the scale of these reproductions changes from a first to a second scale value, and

Fig. 3 a flow chart showing the individual processing steps for the transition of the map presentation from a first to a second scale by means of a softzoom step.

A navigation system designated in Fig. 1 as a whole with 1 for a vehicle not shown in more detail in the drawing has a navigation device 2 with a microprocessor 3 which is connected via a bus 4 to a control device 5 of a map presentation system 6. The navigation device 2 has devices not shown in any more detail in the drawing for determining the position of the vehicle and a memory in which data are stored for a road map. The memory may include, for example, an optical data medium.

The control device 5 has, for its part, a microprocessor 7, which is attached via a further bus 8 to a working memory 9. The bus 8 is also connected via a graphic controller 10 with a display device 11 to reproduce a map presentation 12 (see Fig. 2) of the road map and with an operating panel 13. Using the operating panel 13, a user can transmit data and/or control commands to the control device 5.

The scale or zoom factor with which the map presentation 12 is presented on the display device 11 is calculated, using the microprocessor 7, from operating parameters of the vehicle present in the map presentation system 6. In the embodiment according to Fig. 2, this scale, which is also described in the following as the first scale, is 1 cm : 50 m (figure on top left). As the operating parameter, for example the vehicle speed can be evaluated, whereby at a high vehicle speed a large scale, i.e. a not very detailed map presentation 12, and at a low vehicle speed a small scale, i.e. a more detailed map presentation 12, is calculated. The vehicle speed is measured using a speed sensor 14 and transmitted via a signal line to the microprocessor 7. However, it is also conceivable that the vehicle speed is transmitted via the bus 4 from the speed sensor 14 to the microprocessor 7. The data for the presentation of the map in the calculated scale and data required for slightly differing scales are loaded from the navigation device 2 into the working memory 9. Using the graphic controller 10, the data are processed and presented graphically in the form of the map presentation 12 in the previously calculated scale on the display device 11 (Fig. 2).

After at least one operating parameter of the vehicle has changed, a second scale differing from the first scale is determined in a corresponding way. In the embodiment according to Fig. 2, this second scale is 1 cm : 200 m (figure on bottom left). From the first and the second scale, a series of several interim scales is then determined which are selected in such a way that they bridge the difference between the first and the second scale in steps of the same size (Fig. 2, right). After the map has been shown initially in the first scale, it is then presented consecutively in the individual interim scales and then in the second scale on the display device 11. If, during the display of the map in an interim scale, the data required for a map presentation to be displayed at a later point are not available in the working memory 9, these are loaded immediately from the navigation device. The time required for the subsequent loading of the data is bridged by displaying one or more interim scale map presentations 12 which are present in the working memory 9.

As can be seen in Fig. 2 on the right, the sequence of the map presentations 12 in the interim scales has been selected in such a way that the scale of the map presentations 12 reproduced on the display device 11 approaches the second scale gradually, starting from a first interim scale to be set first (1 cm : 75 m) to a last interim scale to be set last (1 cm : 175 m). It is also clear in Fig. 2 that directly consecutive points in time in which a new interim scale or a new scale of the map presentation 12 is set have constant time differences between them, which are 0.2 seconds in the embodiment. As can be seen from a comparison of the individual map presentations 12 in Fig. 2, the insertion of the map presentations 12 in the interim scales gives what seems to be a continuous, gentle transition from the map presentation 12 in the first scale (Fig. 2, top) to the map presentation 12 in the second scale (Fig. 2, bottom). As a comparison, the dashed line in Fig. 2 also shows the procedure in a method known from the state of the art in which the scale of the map presentation is changed suddenly in just one step from the first to the second scale. It can be clearly seen that after the scale change it is only possible for the user to find his way in the less detailed new map presentation 12 with difficulty.

Figure 3 shows the individual steps in processing the softzoom step explained above in more detail. To start with, the individual interim scales are calculated. A loop is then run through in which the map is displayed in the first interim scale. After this, a check is carried out in the loop as to whether the map was displayed in all interim scales. If this is not the case, the loop is run through again with the next interim scale. Once all interim scales have been run through, the map is shown in the second scale or target scale.

If, whilst the loop is being run through, the map needs to be presented in a target scale deviating from the target scale so far, the running through of the loop is stopped and the interim scales are recalculated. The currently set interim scale then forms the new first scale and the desired target scale forms the new second scale. After this, a new softzoom step is displayed on the display device 11 using the new interim scales calculated in this way.

In the method for presentation of a map on a display device 11 of a map presentation system for a vehicle, the map is therefore firstly presented in a first scale. A second scale differing from the first scale is then defined. At least one interim scale is determined from the first and the second scale. On the basis of the first scale, the map is displayed firstly in at least this one interim scale and only afterwards in the second scale.

Claims

1. Method for presentation of a map on a display device (11) of a map presentation system (6) for a vehicle, whereby the map is presented initially in a first scale, whereby a second scale differing from the first scale is defined and the map is then displayed in the second scale, characterised in that at least one interim scale is determined from the first and the second scale and that the map is displayed after being presented in the first scale initially in at least this one interim scale and only afterwards in the second scale.

2. Method according to Claim 1 , characterised in that a series of several interim scales is determined from the first and the second scale in such a way that these interim scales approach the second scale starting from a first interim scale to be set first to a last interim scale to be set last and that the map is displayed in these interim scales one after the other.

3. Method according to Claim 1 or 2, characterised in that the individual interim scales in the series are selected in such a way that they bridge the difference between the first and the second scale in steps of equal sizes.

4. Method according to Claims 1 to 3, characterised in that directly consecutive points in time in which a new interim scale or a new scale of the map presentation is set have roughly constant time differences between them.

5. Method according to Claims 1 to 4, characterised in that when defining a new scale during the presentation of the map in an interim scale, a new interim scale or a new series of interim scales is determined from the currently set interim scale as the new first scale and the scale to be set as the new second scale and that the map is then displayed in the new interim scale or the new series of interim scales.

6. Method according to Claims 1 to 5, characterised in that whilst the map is being shown in an interim scale, data for a map presentation to be displayed at a later point are loaded from a map data memory into a working memory of a control device of the display device.

7. Method according to Claims 1 to 6, characterised in that the first and/or second scale is defined as a function of at least one operating parameter of the vehicle and that the operating parameter is in particular the vehicle speed.

8. Method according to Claims 1 to 7, characterised in that the first and/or second scale is defined as a function of an entry by a user of the map presentation system (6).

9. A map presentation system (6) for a vehicle comprising:

a display device (11) for presenting a map in a first scale and in a second scale different from the first scale;

characterized by

means (5, 7, 10) for determining from the first and second scale at least one interim scale; and

a graphic controller (10) for displaying the map in at least one interim scale.

10. The map presentation system according to claim 9, further characterized by further comprising a working memory (9) and a microprocessor (7) for generating the map presentation data in accordance with at least one vehicle operating parameter.

11. A navigation system comprising the map presentation system according to claim 9 or 10, characterized by further comprising means for determining the position of the vehicle.

12. The navigation system according to claim 11 , further comprising a memory for storing road map data and means (3, 4) for delivering the road map data to the map presentation system.