A Robust Automatic Digital Terrain Modelling Method Based on Fuzzy Logic

Most of the proposed methods for automatic DTM reconstruction are based on parametric estimation processes with very little capabilities for reasoning and decision making. Human operators which measure DTMs solve interpretation related problems while they carry out the geometric measurements. When working with terrain often decisions have to be made which are of imprecise nature. For those problems fuzzy logic is a perfect basis to design a fuzzy inference process. In this paper we start to develop a fuzzy system for DTM acquisition. Fuzzy logic can be blended with proven concepts and modules of DTM generation and therefore may supplement rather than substitute classical procedures for DTM reconstruction. In a first step we design and implement algorithms for fuzzy feature detection and fuzzy matching in image space. The transfer from image space to object space is then carried out by classical spatial intersection combined with robust finite element modelling for the reconstruction of the terrain surface. Experiments with a Iranian test site are carried out and show the applicability of the procedure. In the next step of future work imprecise hypothetical information extracted from image space will be combined in a fuzzy manner with surface modelling to complete the fuzzy inference system.