EXPERIENCE OF OBTAINING INITIAL DATA FROM GOOGLE EARTH TO BUILD A DIGITAL TERRAIN MODEL

Abstract

The Google Earth system is widely available, which allows to collect geographic spatial information both on a commercial basis and for own needs.

Geodetic measurements are accompanied by measurement errors, they are divided into rough, systematic and random. Systematic errors always distort the measurement result in any direction. Systematic errors are tried to be eliminated by introducing amendments. The analysis of publications shows that the question of obtaining data from the Google Earth system has interested many researchers. Some came to the conclusion that it makes no sense to use geospatial height data, but the use of 2-D data requires research. The relevance is substantiated.

The purpose of this article is to confirm the hypothesis that the Google Earth system provides precisely the systematic errors in finding distances so that by introducing linear corrections it is possible to increase the accuracy of linear measurements in this system.

The order of the experiment:

1) to take several places (territories) located in different parts of the country;

2) in the Google Earth, to find objects with clear contours near the experimenter's location;

2) to measure distances using the Google Earth;

3) to take screenshots of the measured areas;

4) to measure the distance with a tape measure;

5) to calculate the difference;

6) to repeat the experiment in another part of the territory;

8) to calculate the arithmetic mean (using MS Excel);

9) to calculate the standard deviation (using MS Excel).

Three territories located in the northern part of eastern Ukraine were considered. 10 experiments were carried out in each territory.

The hypothesis (that the Google Earth system gives systematic errors in finding distances) has been proven. Now, through the introduction of linear corrections, it is possible to increase the accuracy of linear measurements in this system.