Eccentric (geodesy)

An eccentric (also Offset , lat. Ex centro "from the center"; in the meaning of "moved from the center") is responsible for the geodesics and a surveyor's formation point of the tripod , which intentionally differs from the ideal line.

Measurement of rebounding house corners or points that are difficult to measure by setting an eccentric

Such eccentrics are sometimes set to the side of the best measurement line or the polygon in order to be able to measure some points that are otherwise difficult to access.
In the picture this concerns points 13 and 14 (whereas 22-24 are already visible from point E). Usually the eccentricity is less than 10 meters and the eccentric point is only "attached". In the case of long eccentric stretches, however, the measurement line (in the example ABCDE) can contain the eccentric (i.e. AB-Exz-CDE), which is done, for example, in the case of a very uneven course in a mine or in some tunnel installations .

While survey points are accessible everywhere, this would be problematic for points of the gravity network because of possible vibrations. Therefore eccentric points in the area are marketed here.

See also

• Centering , alignment
• Local measurement
• eccentric
• Eccentric anomaly

Literature and web links

• Franz Ackerl: Geodesy and Photogrammetry , Chapter 20.5, Eccentric Angle Measurement. Georg Fromme Publishing House, Vienna 1959
• Land surveying systems , chap. AGREF, Federal Surveying Office, Vienna 2011
• On the admissibility of eccentrics, Section 6.2 of the Measurement Ordinance 2009

Individual evidence

1. ↑ Swiss Geodetic Commission: SG 95: The new gravity network of Switzerland , Volume 54, ETH Zurich 1999