CONFIGURATION OF THE SYSTEM 
The configuration of the system which would conform with most 
of the requirements listed in the introduction is illustrated 
in Fig.l. The system is based on four camera stations located 
at the corners of a quadrangle. The quadrangle can take the 
shape of a square or a rectangle depending on the design of the 
data acquisition system. 
The four station system can be achieved by raising the stereo- 
metric frame to the required height (Fig.4). Due to the config- 
uration of the four stations,the system is named the QUADRU- 
STATIONAL close-range photogrammetric system. 
The system used in this experiment consists of a specially des- 
igned stereometric stand and two UMK 10/1318 short-range cameras 
(Fig.9). The object to be measured is first photographed from 
position S, and S, (Fig.1), then the horizontal frame upon which 
the camerad are mounted, is raised to position S, and S, and a 
Second stereopair is taken. Throughout this papér, the camera 
stations are referred to as S (S18 and S,.  Stereopairs are 
referred to by the two stations involved in each particular pair. 
FORMULATION OF THE MATHEMATICAL MODEL - NORMAL CASE 
In the normal case of quadrustational system (multi-station/ 
multi-stereo), the camera axes are all perpendicular to both 
horizontal and vertical bases (Fig.2). The mathematical model 
presented hereafter is based on the special symmetrical case, in 
which the system has all four cameras at equal separations. Fig.3 
shows the configuration in the XZ plane for the stations S. and 
52 only. From similar triangles 812184 and S, NA and solving for 
X; we get: 
X =X + xy (zg = Z)/£f; (1) 
e 1 
The relation in the YZ plane is 
Y = ts vu "576 (2) 
1 
The same relationship may be written for the second photograph 
from triangles Syn,a, and SNA. Thus 
X = Xs + x, (25 - 2)/f, sen (3) and Y = Yo +y, (25 -2)/f, oo (4) 
2 2 2 2 
where 
X "Ys 12g (i=1,2) = coordinates of the exposure stations 
i i i 
X,V,Z = coordinates of the object point A 
x, rY, (i-1,2) = image coordinates of ground point A 
on the ith photograph 
and fif, = principal distances of the two cameras. 
B = (Xs 7X6 ) » camera base, H - Zg ~Zg = camera-object 
2 1 1 2 distance 
131