Opportunity rover wheel tracks after recovery from bogging down in Purgatory dune (Credit NASA/JPL-Caltech)
Coupi DEM simulation results showing MER steady state wheel sinakge and soil force network for wheel slip from 0 – 90%.
The DEM model was calibrated and validated using MIT test data for wheel slips up to 50%. Model simulations predicting wheel mobility from 50% to 99% that exceeded the range of known experimental data were shown to be accurate from NASA Glenn Research Center test data. The DEM simulation results are used to define wheel/terrain interactions for the MER rover vehicle dynamics model (ARTEMIS). The approach combines the accuracy of the DEM to describe wheel mobility with the computational efficiency of the ARTEMIS vehicle dynamics model of the MER rover.
Coupi DEM simulation results showing MER time-dependent wheel singage for wheel slip of 99%.
Comparison of Coupi DEM simulation of rover wheel mobility with test data from MIT and NASA Glenn Research Center showing the agreement between simulated and measured wheel drawbar pull (the pulling force of the wheel).
Description of this work and related information about DEM simulation of Mars soil can be found at: