Energy efficiency studies through 3D laser scanning and thermographic technologies

Infrared thermography is generally used in energy efficiency studies in buildings, as well as in moisture detection studies and building inspections for heat losses. Commonly, thermographic studies are qualitative, based on detection of differences of temperature between points: and they only include thermal measurements on specific points or areas, associated to many other factors such as the thermal properties of the materials and environmental temperature and humidity. But this way of working presents a lot of limitations, as there is no way of executing precise quantitative measurements, because thermographic models are simple in geometry and thermographies include geometrical distortions introduced by the camera they are taken with. Laser scanning technology can be an optimal complement for the thermographic measurement, because it provides the metric information that allows the quantification of the thermal studies if the clouds of points are texturized with thermographies. In this paper a methodology for registering thermographies in clouds of points is explained, with the following steps: procedure for processing the metric calibration of the thermal camera, register of thermographies in the cloud of points based on control points, and finally, processing the textured cloud of points to obtain rectified thermographies, with no optical distortions. (C) 2011 Elsevier B.V. All rights reserved.