Page 119 - 4670

calculated. Distance measurements can be related to this
measurement.
Total Station surveying has some advantages in comparisson to
traditional theodolite surveying. These include:

- relatively quick collection of information;
- multiple surveys can be performed at one set-up location;
- easy to perform distance and horizontal measurements with

simultaneous calculation of project coordinates (Northings, Eastings,
and Elevations);
- digital design data from CAD and GIS programs can be
uploaded into and from data collector can perform surveying

calculations with adjustments: COGO and height calculations;
- the horizontal accuracy of a total station is dependent on
instrument type and in general;

- angle accuracy (horizontal or vertical) can range from 2 to 5;
- distance accuracy can range from +/- (0.8 + 1 ppm x D) mm to
+/- (3 + 3 ppm x D) mm, where D = distance measured. A ppm (parts

per million or mm/km) correction is entered into total station; it takes
into consideration changes of the speed of light in air defense of the
density of the air.

- the vertical accuracy is highly dependent on leveling the
instrument. Thus, two leveling bubbles are provided on the instrument
and are referred to the circular level and the plate level:* Sensitivity of
Circular level = 10’ / 2mm; * Sensitivity of Plate level = 30” / 2mm;

- vertical elevation accuracy is not as accurate as using
conventional survey levels and rod techniques.

VI. INDIVIDUAL WORK

Task 1. Write down a summarizing sentence for each
paragraph of the text and translate the text.

Types of geodetic instruments

Geodetic instruments are mechanical, optical-mechanical, electro-
optical, and radio electronic apparatus for the measurement of the

lengths of lines, angles, and super elevations in the construction of
astronomical-geodetic grids and leveling nets; for mapping,
construction, and installation; and for the operation of large
engineering structures, radio-telescope antennas, and so on. Geodetic

119