- Vorführexperimente, Videos
Friction and Smoothness of a Surface
Basic explanation of friction of sand (and other materials).
- Wissenschaftliche Artikel
Rolling friction on a granular medium
Experimental study for the rolling of spheres on a granular bed.
Rolling resistance of a spherical pod on a granular bed
The motion of a spherical ball rolling without slipping or plowing on a granular bed is studied. A definition of the rolling resistance force and torque is supposed. A simplified model predicts the velocity independence and suggests an inverse dependence of the rolling resistance coefficient on the reduced inertia of the ball.
Rolling resistance on sand
Experiments are conducted to measure the resistance experienced by cylindrical shells rolling over flat beds of several granular media. The results are compared to a theoretical model based on Mohr-Coulomb rheology.