Vision based active antenna-basic considerations on two-points detecting method

This paper is an extended version of the vision based active antenna (VBAA) that can detect the contact force, the stiffness of the environment, and the contact location between an insensitive elastic antenna and an environment, through the observation of the antenna´s shape by a camera. If measured points are on the antenna, two arbitrary points are sufficient for computing the contact location and the contact force uniquely. In a practical application of VBAA, however, the measured points are not always on the antenna. In this paper, we show the condition for uniquely obtaining both contact location and contact force under the situation that the measured points are not always on the antenna. We also show a new compensation method to improve the sensing accuracy. We further verify our idea experimentally