Functions for modeling vehicle-ground interaction for an Avant front-end loader were developed for the simulation of robotic earth-moving tasks. A stand-alone Matlab program was used to test the functions, which are meant to be the first step in implementing vehicle-ground interaction capability in the Generic Intelligent Machines (GIM) Integrator virtual simulator, part of a joint project between the Helsinki University of Technology (TKK) and the Tampere University of Technology (TUT). The test program consisted of an automated sequence of scooping and dumping operations for moving a pile from one location to another. Slope re-settling algorithms were developed to make the simulation more realistic. Ground penetration by the scoop was purely kinematic, i.e. no forces were modeled. The overall program provides a good simulation of volume distribution and soil behaviour during earth-moving tasks, and total volume is conserved within a small margin.