| Summary: | Trigonometric leveling is one of the methods to determine the height
differences between points. This could be done by measuring vertical angle and
distance using Total Station. The accuracy of this method depends on the precision
of the vertical angle, distance, instrument�s height and reflector�s height data. This
research aims to find out the impact of giving the correction to the instrument and
reflector height to the precision and accuracy of the height determination using Total
Station at Borobudur vertical monitoring network.
Data used in this research are leveling data using Leica SPRINTER-100 of
Borobudur network in 2011 and trigonometric leveling data using Nikon DTM-322
Total Station in 2012. Correction was given to instrument and reflector height data of
Borobudur network in 2012, in order to have direct vertical height of the observed
points. Least square adjustment with minimum constraint was done to estimate the
height and the precision of each point for three different networks, the leveling
network, the trigonometric network without correction of instrument and reflector
height, and trigonometric network with correction applied. Comparative study of the
adjustment result from the leveling and trigonometric networks was done using
Fisher and student t-test with 95% level of confidence.
The result of comparative study show that the precision of estimated height
from trigonometric network with correction applied and the leveling network was
differ significantly. The average height precision of trigonometric data with
correction applied was 0,03 m and the height precision of the leveling data was 0,002
m. The correction of instrument and reflector height of 2012 Borobudur vertical
network Borobudur increased the precision of the estimated point slightly (about
0,002 m), but gave significant correction to the estimated height to the level of 0,02
m. It can be concluded that the precision of height determination using Total Station
in this case has not meet the leveling precision, thus further study on trigonometric
leveling need to be done.
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