3D Contour Following for a Cylindrical End-Effector Using Capacitive Proximity Sensors

In this paper we've equipped a cylindrical end-effector with an array of capacitive sensors in order to implement 3D contour following. During the task, using proximity servoing, the sensors are aligned parallel to the surface and kept at a target distance. In addition, due to the spatial resolution, it's possible to estimate the surface's curvature in two dimensions along the rows and columns of the array. We show how a compound movement can be derived from both curvatures that pre-aligns the end-effector in each step, yielding a predictive component for the control scheme. We evaluate our approach with different geometries and show that the curvature information produces smooth contour following paths. We show that the system can handle speeds up to 150mms(-1).