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In this paper the complete setup of the demonstration breadboard of the photogrammetric diagnostic tool is presented 
with special emphasis on the photogrammetric characterization of the breadboard, calibration strategies and the 
evaluation of image sequences with respect to the specific needs of fluid physics experiments under microgravity 
conditions. 
2. THE BREADBOARD 
The breadboard developed for ESA/ESTEC to demonstrate the application of close range photogrammetry to fluid motion, 
e.g. drops and columns, within a fluid matrix consists of the fluid cell, the motion device, the drop and column dummies 
and the photogrammetric front end. The photogrammetric front end consists of three electronic CCD cameras which form 
a compact setup in front of one observation window of the fluid cell and means for the calibration of.this photogrammetric 
measuring unit (see fig. 1). 
  
Figure 1: The breadboard 
2.1 The fluid cell 
The dimension of the fluid cell and the fluid body chosen are representative concerning typical microgravity experiments 
[ESA 1991] (see figure 2). The objects can be moved within the fluid cell with an inner size of 50 x 50 x 70 mm”. A double 
walled window has been chosen to represent the thermal insulation of a typical cell and the window thickness of 10 mm is 
representative for interferometric windows. A reseau grid is placed on the inner sides of the the front and back window of 
the fluid cell. Top and bottom windows are also made of glass to be able to use additional observation techniques. The 
objects are inserted into a fluid matrix, here an optical matching oil is used to simulate true optical conditions. The drop 
and the fluid column representing the model scene are manufactured from solid state transparent materials. To simulate 
different sizes of the drops high precision glass balls with diameters from 2 - 20 mm can be attached to a moveable rod, 
to simulate the column bodies three different objects with cylindrical, spheroidal and hyberboloidal shape are 
manufactured from plexiglass and can be mounted instead. The moveable rod can be attached to a linear motion unit PI 
4200 from Physics Instruments, which is controlled by PC via an interface board to simulate the motion. 
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Figure 2: The fluid cell with motion unit 
IAPRS, Vol. 30, Part 5W1, ISPRS Intercommission Workshop "From Pixels to Sequences", Zurich, March 22-24 1995