In order to characterize the mechanical behavior of grain piles, we investigate the response of a noncohesive two-dimensional packing of cylinders submitted to a localized force. By means of image processing, we obtain an accurate measurement of the individual grain displacements in the reversible regime of deformation. The measured displacement field deviates unambiguously from the predictions...

Mohammed E. Haque, Ph.D., PE, Texas A&M University, Department of Construction Science, College Station, TX 77843-3137 [email protected] Abstract  With the advances in information technology over the last decade, the traditional teaching format of having an individual lecture to an audience has been supplemented and, in some cases, replaced by the rapid development and implementation of new ...

We present a composite forward model of the mechanics of an excavator backhoe digging in soil. This model is used to predict the trajectories developed by a closed-loop force based control scheme given initial conditions, some of which can be controlled (excavator control parameters), some directly measured (shape of the terrain), and some estimated (soil properties). Since soil conditions can ...

Considering unsaturation conditions of soil significantly helps to produce relatively real results. Numerical methods have been assumed as conventional methods in soil mechanics to examine soil behavior. However, the accuracy of numerical methods dramatically depends on applying the appropriate behavioral model to solve problems. One of the known elastoplastic models for unsaturated soils i...

Subsoils are widely used on tillage and combination machines. The tiller of the combined machine for preparing soil sowing melons gourds carries out strip loosening subsoil layers. study aims to theoretically determine traction resistance a deepener gourds. uses basic provisions mathematics, theoretical mechanics, agricultural mechanics. In studies, it is assumed that destruction under influenc...

L-band (1-2 GHz) microwave radiometry is a remote sensing technique that can be used to monitor soil moisture, and is deployed in the Soil Moisture and Ocean Salinity (SMOS) Mission of the European Space Agency (ESA). Performing ground-based radiometer campaigns before launch, during the commissioning phase and during the operative SMOS mission is important for validating the satellite data and...

This paper investigates slip-based traction control of a planetary rover that travels over natural rough terrain. Special attention is made on tire-soil traction mechanics and articulated body dynamics. Experiments are carried out with a rover test bed to understand the physical behavior of tire-soil interaction and, thereby, a traction model is investigated using the tire slip ratio as a state...