1-3-4 
navigation, objects measurement, environment data 
collection and other functions. 
3.1 Car Navigation 
There are two navigation modes. The one is free 
navigation. The other is the optimal road navigation. 
Free navigation mode is to point the vehicle position 
and orientation in real-time on the digital map. The 
optimal navigation gives the shortest road in time or in 
distance from start point to terminal point. The shortest 
route is marked with a different color. The interface on 
the screen is divided in to two parts. The left digital map 
is in driver coordinate system. The right part is in map 
coordinate system. The input & output of the 
information are done by voice in multi-media 
environment. Inertial navigation instruments based on 
GIS are also included to keep track of the vehicle’s 
position when GPS signals are temporarily lost 
3.2 Object Measurement 
In WUMMS, there is an absolute positioning sensor i.e. 
GPS receiver. There are two types of Relative 
positioning sensors, passive imaging sensors such as 
video cameras, and active image sensors such as a laser 
range finder. Laser range finder is a promising tool for 
accurate distance measurement. The digital images are 
captured simultaneously, and each image is time lagged 
using GPS data. The GPS data are then used to geo- 
reference the stereo image captured by cluster of CCD 
camera and thus form the basis of the photogrammetric 
measurement system. Stereo triangulation and image 
processing technology are subsequently used to provide 
three-dimensional coordinates of selected features in 
object space. The solutions with and without INS data 
are under investigation. 
3.3 Environment Data Collection 
In WUMMS the sensors that measure the temperature, 
air pressure, gravity, content of fluid about environment 
etc besides the position of object, can be implemented. 
For instance, an operator can collect attribute 
information by recording voice on audiotapes. This is 
especially useful for collecting street addresses and road 
names from a moving van. Digital voice can be stored 
just as any other attribute associated with a geographic 
position. 
3.4 Data Acquisition, Processing, Storage and 
Management 
The conceptual layout and data flow of an integrated 
mobile mapping system is generally composed of 
modules of data collection, data processing and data 
management (see Figure 4). 
Figure .4 Conceptual Design of A Mobile Mapping System that integrates Various Sensors, 
Data-Analysis Function an Object-Oriented, Multi-Media Database.(Kurt Novak, 1995) 
The mobile mapping systems collect land-related 
information, that requires positioning sensors (such as 
GPS ) to determine the absolute location of the mapping 
vehicle at any time. A number of other sensors are 
installed to obtain features relative to the vehicle and 
environment. But the showing concept from Fig 4 is not 
comprehensive. The MMS is merely assistance for 
generating the database of spatial and attribute. 
Therefore we can acquire information or data based on 
existing GIS. In other words, we can find new 
information based on old GIS database. We can acquire 
many information and knowledge from existing GIS 
database by means of data mining. For example, one can 
find and utilize known control points, roads for 
photogrammetry reconstruction of the new CCD images. 
All collected data must be integrated in order to create a 
comprehensive, multi-media database which combines 
spatial positions with attributes, images and various 
other measurement. Usually, absolute positions must be 
available before relative observation can be derived,