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Fig. 4. When the friction is eliminated through vibrations the little play between 
the studs and the slot-edges correlate and facilitate movements of the studs. The 
figure shows the movements in some points. Compare the 2-mm-length. 
the slotted templets can be practically made with angles with very small 
errors and in order to facilitate and quicken this work new prototype- 
instruments for fast and accurate point transference and templet slot- 
ting have been designed and are built under the authors’ supervision 
for the Swedish Army Material Command at the Royal Inst. of Tech- 
nology.*) The instruments will be shown at the VIII International 
Congress of Photogrammetry. 
The assembly of the slotted templets is the next occasion for errors to 
occure, and to a dominating extent do occur. Friction between studs and 
slot-edges, between the templets and between templets and triangulation 
table decreases the automatic adjustment of the templet positions which 
is the main advantage of the MRT. The necessary small "play" between 
studs and slotedges — the diameter of the studs must be 0,05— 0,15 
mm less than the width of the slots- and the frictional forces and acci- 
dental occurences when the templets are assembled, correlate and re- 
sult in rather big errors with the error vectors in a whirllike pattern. 
sometimes these "errors" also hinder the completion of the assembly of 
the templets. Through vibrating the assembly the friction is lowered, 
which facilitates the assembly. However it does not reduces the influ- 
ence of the play on the final accuracy very much. This, however, is 
according to the author's investigations achived through the special 
measure to incline the assembly slightly, in order to get a small com- 
ponent of the gravity force parallel to the triangulation surface, and 
*) As there is also a need for a star-templet apparatus for triangulation in a 
scale 2—3 times the photography scale such an equipment is also designed and 
manufactured and will also be displayed . 
  
  
  
  
  
  
  
  
  
  
  
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