Research on Laser Range Scanning and Its Application

At present, there are lots of methods to acquire geographic information infrastructure. The traditional acquisitions of spatial data mainly use the methods as follows: surveying directly in the field, digitizing from existing maps, and photogrammetry. Data digitized from existing maps are often dated and go behind time. Optical images, which are more fundamental and matured means, include enormous and visual information, and have a good speed to capture data. But it is rather difficult to recognize, interpret and model objects included in image. And highly complicated, expensive stereo measurement instrument and skilled operators characterize photogrammetry. The approaches between field survey and photogrammetry are time-consuming, and the former is often low efficiency and the latter results in high cost. Moreover, DEM generated from photogrammetry render problems if the topography shows only minor differences in height and/or in significant contrast, and in forested area is problematic, too. Laser-scanning has been accepted to generate DEM for several years.Laser-scanning technique, which is divided into both ground-based and airborne according to its mounted platform, is mainly used to such applications as surveying bulk, measuring profile, generating surface DEM, and so forth.We focused on the ground-based laser-scanning technique including the development of algorithms, model, visualization, and of the applications suitable to laser scanning. Ground-based laser range scanner is one of the potential sensors for the automatic reconstruction of detailed surface data of the spatial objects. In our research, we employed fixed platform with motive station. In this paper, the development and principle of laser range scanning is introduced. The method of volume measurement by use of laser scanning is discussed and a system for this work is developed. Comparing with traditional surveying method, laser scanning has advantages in precision, automation, visualization as well as efficiency and working situation.