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and will be presented at the Ottawa 
Symposium. The most important 
activities are reported below. 
Integration of GPS, INS, Laser Scanners 
and Digital Cameras for Aerial Mapping: 
GPS is used for automatic positioning and 
orientation of the sensor platform. With 
an operational, automatic ambiguity 
solution available, real-time kinematic 
GPS can be used for sensor platform 
positioning. Developments are under 
way to fully integrate inertial systems 
with GPS for on-line altitude 
determination, however, the high price of 
inertial units is still an obstacle. Digital or 
video images are collected together with 
the positional information. Aerial video is 
becoming a popular tool for taking 
inventory of forests and wildlife 
management. As high resolution digital 
cameras (» 2,000 x 2,000 pixels) are 
practically not available for aerial 
mapping, digital image collection systems 
are mostly restricted to time critical 
applications as well as mapping of linear 
features. This is one of the research areas 
that will need more attention in the 
future. Laserscanners are being used for 
surface reconstruct ion and DRM 
generation. They are in the prototype 
stage and are promising tools for real- 
time orthophoto production. There are 
also interesting developments going on to 
install digital cameras in the wing-tips of 
airplanes to take stereo-image pairs of 
powerlines. The position and orientation 
of the airplane is determined by 3 GPS 
antennas. 
Vehicle Navigation Applications: a 
number of infrastructure mapping 
systems have been developed over the 
past years. They are based on the 
integration of GPS and INS for 
positioning vehicles continuously. 
Different imaging sensors are available for 
video-logging and attribute collection, as 
well as stereo-vision systems for spatial 
519 
positioning of objects in the environment 
of highways. Data collected with these 
systems are immediately stored in a GIS. 
Other research deals with autonomous 
vehicle navigation. Image sequences are 
analyzed by tracking points and linear 
features along the road to estimate the 
vehicle's motion and speed. On-line 
triangulation techniques, such as Givens 
transformations, and 3D Kalman filters 
are applied. In this category we also 
include the developments in the IVHS 
(intelligent vehicle highway systems) 
field. They mostly deal with the 
installation of moving map displays and 
traveler information systems in cars and 
trucks, to show the position of the vehicle 
in real-time on a digital map. 
Integration of GIS and Image Analysis: 
the integration of GIS data is very useful 
for automatic, digital image analysis. This 
is especially true in real-time 
environments, where different sensors are 
available that can support image analysis. 
Automation is a must in such an 
environment and can only be achieved by 
proper interfaces. Multi-media, spatial 
data-bases enhanced by different types of 
digital imagery provide valuable 
information in this endeavor. 
Working Group II/I News 
* Development of a report/bulletin on 
sensor and GIS integration is on-going. 
It will probably be completed for the 
Symposium in June 1994. 
* A survey is being conducted on the 
state-of-the-art in real-time mapping, 
including the activities of different 
institutions and Commercial 
companies world-wide. 
* Two technical sessions will be 
organized at the ISPRS Commission II 
Symposium in Ottawa, Canada (June 
1994).