This paper presents a new strategy for behavior-based navigation of field mobile robots on challenging terrain, using a fuzzy logic approach and a novel measure of terrain traversability. A key feature of the proposed approach is real-time assessment of terrain characteristics and incorporation of this information in the robot navigation strategy. Three terrain characteristics that strongly aff...

Impact cratering produces characteristic variations in the topographic power spectral density (PSD) of cratered terrains, which are controlled by the size-frequency distribution of craters and the spectral content (shape) of individual features. These variations are investigated here in two parallel approaches. First, a cratered terrain model, based on Monte Carlo emplacement of craters and ben...

Direct numerical simulation is used to investigate the transition induced by threedimensional isolated roughness elements in a supersonic boundary layer at a free stream Mach number of 3.5. Simulations are performed for two different configurations: one is a square planform roughness and the other is a diamond planform roughness. The mean-flow calculations show that the roughness induces counte...

A numerical simulation of micro Poiseuille flow has performed for rarefied and compressible flow at slip flow regimes. The wall roughness is simulated in two cases with triangular microelements and random micro peaks distributed on wall surfaces to study the effects of roughness shape and distribution on flow field. Two values of Mach and Knudsen numbers have used to investigate the effects of ...

Digital terrain models (DTMs) are datasets containing altitude values above or below a reference level, such as ellipsoid tidal datum over geographic space, often in the form of regularly gridded raster. They can be used to calculate attributes that describe shape and characteristics topographic surfaces. Calculating these requires multiple software packages expensive specialized. We have creat...

The improvements of polarimetric SAR data inversion algorithms are discussed and presented. The confounding influence of roughness and vegetation cover on the estimation of the soil moisture contents are considered in the inversion algorithm that estimates moisture content and roughness parameters simultaneously from the pertinent combination of polarization measurements. The estimation of soil...

Interpreting laser data to allow autonomous robot navigation on paved as well as dirt roads using a fixed angle 2D laser scanner is a daunting task. This paper introduces an algorithm for terrain classification that fuses seven distinctly different classifiers: raw height, roughness, step size, curvature, slope, width and invalid data. These are then used to extract road borders, traversable te...