A new consideration on active antenna

This paper discusses the sensing accuracy of the active antenna that can detect the contact location between an insensitive flexible beam and an environment through the measurement of the rotational compliance of the beam in contact with the environment. During pushing motion of antenna, the contact point generally shifts on the environment's surface, which either underestimates or overestimates the rotational compliance and eventually brings a sensing error for localizing the contact point. The goal of this paper is to consider the effect of the environment's curvature on the rotational compliance. We show that the rotational compliance of the antenna being in contact with a curved environment depends on not only the contact distance but also on a new nondimensional parameter including the pushing angle and the environment's curvature where the antenna makes contact. We further show experimental results to support the theoretical analysis for various environments with different curvature.