Volumetric Ergodic Control
This addresses the limitation of existing ergodic control methods that model robots as non-volumetric points, offering improved efficiency for robotic search and manipulation tasks, though it is incremental in extending prior formulations.
The paper tackles the problem of ergodic control for robots by introducing a volumetric state representation to account for physical volume, improving coverage efficiency by more than a factor of two while maintaining a 100% task completion rate across experiments.
Ergodic control synthesizes optimal coverage behaviors over spatial distributions for nonlinear systems. However, existing formulations model the robot as a non-volumetric point, but in practice a robot interacts with the environment through its body and sensors with physical volume. In this work, we introduce a new ergodic control formulation that optimizes spatial coverage using a volumetric state representation. Our method preserves the asymptotic coverage guarantees of ergodic control, adds minimal computational overhead for real-time control, and supports arbitrary sample-based volumetric models. We evaluate our method across search and manipulation tasks -- with multiple robot dynamics and end-effector geometries or sensor models -- and show that it improves coverage efficiency by more than a factor of two while maintaining a 100% task completion rate across all experiments, outperforming the standard ergodic control method. Finally, we demonstrate the effectiveness of our method on a robot arm performing mechanical erasing tasks.