An Advanced Digital Stereophotogrammetric System (ADSS)- 
Current Developments at the Technical University of Berlin 
Gerhard Koenig, Wolfgang Nickel, Juergen Storl 
Technical University of Berlin 
Photogrammetry and Cartography, EB9 
Straße des 17. Juni 135 
D-1000 Berlin 12, FRG 
Commission II 
Abstract 
Digital image data are increasingly adopted in the field of photogrammetry. This development 
has led to a new kind of stereophotogrammetric instrument, the digital stereoplotter. After the 
completion of an experimental system at the Technical University of Berlin (TUB) a new system 
is under development which will provide the performance needed in stereophotogrammetric 
applications. 
The paper describes design and concept of the ADSS. Hardware aspects concerning parallel 
architectures, especially the transputer approach, are discussed. Based on the Paracom Multi- 
Cluster-1 series environment the application of parallel techniques is demonstrated. Helios, a 
distributed operating system, and its tools, which allow comfortable programming, are presen 
ted. First comments are given on experiences with transputer networks concerning the perfor 
mance of the system. 
Introduction 
Fully digital systems are a topic of discussion in the photogrammetric community since the early 
eighties (SARJAKOSKI 1981, CASE 1982, ALBERTZ & KOENIG 1984). Microelectronics and sen 
sor technologies have seen enormous advancement over this period while at the same time 
hardware costs strongly decreased. This development makes working tools available at an ac 
ceptable price that offer analytical plotter functionality and in addition have further strong attribu 
tes (SARJAKOSKI 1981, GRUEN 1988) such as 
• no need for manual image handling, 
• lack of high-precision opto-mechanical parts, 
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