Archeologist Rob Thrift is using an electronic total data station to map cultural features at the farmstead. He is entering data for a shot he just made (a point on a feature) into the "data collector." The theodolite on the tripod uses optics to sight in on a prism on top of a survey rod. When a button is pushed, the instrument sends out an electronic beam that bounces off the prism and returns to the instrument, which accurately measures the travel time for the electronic signal. This data is then used to calculate the distance and elevation. Total stations are used for land surveying and mapping. |