Aufnahme- und Erfassungstechniken Raumbezogener Daten zum Aufbau und zur Aktualisierung von Dreidimensionalen Gebäudeinformationssystemen

Abstract

The construction and maintenance of buildings demand a great number of technical and design information. As tools of information acquirement maps, plans, metric photographs are available. Usually, the available data is treated independently and this can lead to mixing up the data and in consequence to not satisfactory preparation of the decision making process. The volume of the available information related to the buildings and their environment is growing continuously, it cannot be processed without proper tools, thus the decision making is impossible in the lack of those. The Building Information System (BIS) containing geometric, utility and graphical data aims at the solution of these problems. The capture of utility and geometric data related to the buildings can be performed directly (primary data capture) or indirectly (secondary data capture). In the first case the data is captured directly from the building or its digital image. The direct acquisition of utility data frequently can be linked to the acquisition of the building`s geometry. By secondary data capture, data are digitized from existing data sets (plans, other materials). In primary data capture one can apply the methods of surveying and photogrammetry. In the first case it is advantageous to use equipment and methods providing electronic recording of digital data. In the second case both the traditional and digital methods of photogrammetry are in use. The methods of secondary data capture are based on such archive materials as maps, plans, metric images. In this case two ways are applied for filling up the BIS: digitizing of existing maps, plans, photogrammetric images, and taking over of existing digital data sets. To the latter method we have to make the comment that the design realized by some kind of up to date CAD software results in data which is suitable, if checked properly, for direct transfer to the BIS. In this case we need converter modules for transferring the data without any loss. Theoretical studies in our days and also practical experience show that the methods of data capture and data processing related to geometric and utility data for BIS should be developed with consideration of local circumstances and possibilities. If separately applied, the photogrammetric or surveying approach can deliver only a part of the required three-dimensional information for building description. Therefore in the practice several methods are combined for data capture, to ensure the economical way of building up the geometric and utility data set.