An integrated GPS and Total Station instrument for cultural heritage surveying: the LEICA SmartStation example

Total stations and GPS receiver are normally used separately for terrestrial survey of cultural heritage, and the natural development has been the production of a single instrument where both a GPS and a total station work together. Several problems, such as the different reference systems used by the two techniques, require a geodetic approach to solve them. Leica Geosystems was launched SmartStation, an innovative product that integrates a GPS double frequency receiver and a Total Station series 1200. The real integration is obtained from a new firmware that is able to manage and store both kinds of measurements: angle and distance, RTK and other GPS observations. The GPS observations are functionally to the reference system set-up, while total station measurements provide the north direction of the reference system, and carry out a detailed survey using celerimetric measurements. A new instrument implies a new survey methodology, compared to classical techniques. Several survey scenarios can highlight the main advantages, that is no control points are needed, and there are no long traverses, or resections. To evaluate these new technologies and compare them with traditional ones, a case study survey has been conducted on the Porte Palatine, an archaeological building site in Turin, where a topographic referenced network was signalized and measured. The comparison focused on the time-saving, the staff needed to conduct the survey (skilled and/or unskilled), and the easiness of the survey operations.