The examples and perspective in this article deal primarily with Germany and do not represent a worldwide view of the subject. (March 2023) |
In surveying, free stationing (also known as resection) is a method of determining a location of one unknown point in relation to known points.[1] There is a zero point of reference called a total station. The instrument can be freely positioned so that all survey points are at a suitable sight from the instrument. When setting up the total station on a known point, it is often not possible to see all survey points of interest. When performing a resection (free stationing) with the total station, bearings and distances are measured to at least two known points of a control network. With use of a handheld computer, recorded data can be related to local polar coordinates, defined by the horizontal circle of the total station. By a geometric transformation, these polar coordinates are transformed to the coordinate system of the control network. Error can be distributed by least squares adjustment. Upon completion of observations and calculations, a coordinate is produced, and the position and orientation of the total station in relation to where the control network is established.[citation needed]