Tactile Ergodic Coverage on Curved Surfaces

In this article, we present a feedback control method for tactile coverage tasks such as cleaning or surface inspection. Although these tasks are challenging to plan due to the complexity of continuous physical interactions, the coverage target and progress can be effectively measured using a camera and encoded in a point cloud. We propose an ergodic coverage method that operates directly on point clouds, guiding the robot to spend more time on regions requiring more coverage. For robot control and contact behavior, we use geometric algebra to formulate a task-space impedance controller that tracks a line while simultaneously exerting a desired force along that line. We evaluate the performance of our method in kinematic simulations and demonstrate its applicability in real-world experiments on kitchenware. Our source codes, experiment videos, and data are available at https://sites.google.com/view/tactile-ergodic-control/.