A Finite Element Approach to Enhance Aquatic Traction for Amphibious Spherical Robot

The paper reports the possibility to extend the functionality of a land spherical robot such that it can also be freely movable while floating on water. To compromise for both computational convergence and CPU time, a simplified 2D model with reasonably meshed components is used for time-dependent study based on the arbitrary Lagrangian-Eulerian (ALE) model of the fluid-structure interaction module. We observed that while a sparse fin structure can already provide good aquatic traction, installing excessive fins is not only unhelpful, on the contrary it is proven in our simulations that eventually it would even be detrimental due to the unexpected reverse pushing from the turbulence eddies. These results would definitely provide some insights and design guidelines for the implementation of aquatic fins to our current land spherical robot to enhance its amphibiousness.