Nuovi Metodi Operativi per il Rilievo Architettonico: icnografia con il distanziometro a raggi infrarossi

Architectural surveying has for many years been approached in a manner which was so amateur that it left many people wondering whether it really was a separate discipline. Nowadays, the researcher's operational and algorithmic mentis form rejects this conception and suggests working on the methods, techniques and sequences of operations which are feasible and led to results; it also suggests recording every minute of this work, to describe it down to the minutest detail and be completely open about the errors committed and the choice criteria. The research presented here concerns a small piece of the mosaic which could be called «New Operative Methods for Architectural Surveying ». It is a programme involving. several Italian universities and concerns a method which simplifies and makes planimetric surveys quicker and more reliable. The method simplifies surveying, because the procedures 'can be carried out even by a single operator and makes it quicker because the field tests have shown a considerable reduction in the working times and finally it is more reliable because the procedure allows checking for any errors made during measurement. The method is based, in short, on the use of a theodolite equipped with an infra-red ray diastimeter which can operate even without a reflecting prism, i.e., by exploiting its own reflection on the surface under study. The diastimeter is accompanied by a laser which, thanks to a simple system of mirrors, produces a ray which is coaxial to the viewpoint of the diastimeter and allows sighting which does not require collimation via the spyglass. It is evident that while allowing a rather rapid surveying for polar coordinates, this method can free the surveyor from the tiring operations of trilateration and interacting with a computer and allows an almost immediate or even on-line results, i.e., at the very moment of measurement, attaining a sort of tracing of the building. To check both the quantity and quality errors made by the instrument, in our case, a WILD DIOR 3002 DISTOMAT, a simple and effective measuring instrument was prepared in the basement of Pescara University's Faculty of  Architecture. The instrument's performance was checked on various materials as were the different situations of the incidence of the ray of the surface being studied. The results obtained showed that the error is very constant and can therefore be checked by using a suitable procedure which consists in calibrating the instrument in the field. Three procedures were then experimented for collecting measurements and linking the models: the first, or «central» consisted in placing the instrument in a first position from which one could correspond all the other positions, measuring their three-dimensional coordinates vis-a-vis a reference system which originates from the first position. The second, or «tracking», is nothing more than the typical polygonal procedure. The third, or «support points» is that which furnished the best results, in terms of both precision and feasibility. In conclusion, research on surveying procedures is still an open field and there is much to discover as regards both the philological aspect and also the use of new technologies. When these studies are completed, architectural surveying, as regards both its practice and teaching, will be seen in a completely different light. The method will be appreciated to the same extent that the graphic quality of a plan is today, the traditional 'plan' will find itself in a context which no longer comprises tables, but various information and coordinates, which are however nonetheless aimed at satisfying the common objective of any scholar of architecture: knowledge.