TravelPilot 
Vehicle Information System with Route Guidance 
Fig. 3.2 
  
  
   
satellite 
receiver 
  
  
  
memory card for Yellow Pages 
  
Route Guidance with symbol and voice instructions 
compass 
     
traffic messages (via radio broadcasting 
or road infrastructure). 
Direct selcetion of goals, relief of motorists through easily understandable driving recommendations 
(symbol and voice instructions), automatic calculation of alternative routes, integration of 
information on traffic situations and Yellow Pages. 
voice emission 
  
CERCA 
ES SI 
  
  
À TELE ATLAS 
available. In this way locations can be improved 
continuously. The resulting position is shown to the driver 
as a symbol, together with a map representation in the 
background on a vector display. 
The route finding function calculates the optimal route from 
the current position to a desired destination. For this 
purpose a weighted graph is built from the road network, 
where edges are road segments which are often called 
links. These links are ranked according to different criteria. 
The most important criterion is the travel time per link, 
derived from its length and road class. Travelling durations 
are further influenced by the traffic regulations (e.g. speed 
limits etc.), and number of turns, traffic lights and complex 
intersections. The ,turn-by-turn" driving instructions are 
derived on the basis of the determined optimal route. If the 
driver doesn't follow the recommended driving instruction 
at some location, the system calculates at once a new 
optimal route from this location to the desired destination. 
range / medium-range two-way communication between 
the infrastructure and drivers). In regions, where no 
infrastructure is available, autonomous vehicle navigation 
systems are put into use. 
The further development is to integrate the information 
from telephone directories such as yellow pages and 
messages about the actual traffic situations into the route 
finding and guidance process. 
3.3 Multimedia travel guides 
When combined with information about catering, tourist 
attractions, cultural sites and events, MultiMap forms the 
open basis for extremely useful and attractive multimedia 
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K7/PDK650918 e1 
travel guides, with which one can plan his trips or cultural 
outings at home comfortably, before he really starts. He will 
be accompanied on his voyage through Europe by these 
guides, if they are installed on portable or hand-held PC's. 
One of this kind of products is MERIAN screen from the 
tourist guides publisher Gräfe und Unzer. 
3.4 StreetNet, StreetMap and StreetPilot 
StreetNet and StreetMap for Europe build different subsets 
of MultiMap. StreetNet is of high data quality with detailed 
information, 5 - 25 m geometric accuracy and finer road 
classification, therefore is suitable for GIS-application and 
fleet management. StreetMap is of standard data quality 
with less information, 25 - 100 m geometric accuracy and 
gross road classification and is thus conceived for desktop 
mapping and geo-marketing. 
StreetPilot is a route planning program for DOS/windows, 
containing digital data from MultiMap. It can calculate 
routes from city to city and street to street with detailed path 
description and clear map display. It can be extended with 
following additional modules: GPS positioning, object 
management, geo-coding through a DDE interface, DAS 
hotel and restaurant guide, train time table of federal 
railways (Bundesbahn) and network version. 
4. Conclusion 
The future work is to complete digital road maps for the 
whole Western Europe by the end of 1998 (Fig. 4.1). We 
will market the existing products and develop new MultiMap 
products. Our effective approaches of quality controlling on 
International Archives of Photogrammetry and Remote Sensing. Vol. XXXI, Part B4. Vienna 1996