Imaging Ladar for 3-D Surveying and CAD Modeling of Real-World Environments

To establish mobile robot operations and to realize survey and inspection tasks, robust and precise measurements of the geometry of the 3-D environment is a required basic sensor technology. For visual inspection, surface classification, and documentation purposes, however, additional information concerning reflectance of measured objects is necessary. High-speed acquisition of both geometric and visual information is achieved by the described active ladar, developed by Zoller and Fröhlich (Z+F). In contrast to other range-sensing devices, the Z+F system is designed for high-speed and high-performance operation in real indoor and outdoor environments, emitting a minimum of near-infrared laser energy. It integrates a single-point laser measurement system and a mechanical deflection system for 3-D environmental measurements. Experimental results are reported from surface inspections in tunnels, the generation of 3-D CAD models of a work cell in an automotive manufacturing plant, the modeling of free-form surfaces such as historic sculptures, and applications in mobile robot navigation.