抄録
This paper proposes the Self-excited Dynamic Active Antenna (SDAA) that can detect a contact location between an insensitive flexible beam and an object through observation of the fundamental natural frequency of the beam in contact with the object. The main part of SDAA is composed of a flexible beam, one permanent magnet and two electromagnets. The permanent magnet is attached to a part of the beam and two electro magnets are positioned at both side of the permanent magnet with a small gap. These magnets contribute to not only exciting the motion but also changing the boundary condition of the beam. We analyze the rerationship between the displacement of the permanent magnet and the induced force, and show the linear spring-like behavior of the magnetic force. We also show that the contact position is uniquely determined by utilizing two fundamental natural frequencies before and after changing the boundary condition, whereas both the fundamental and the second natural frequencies are necessary for localizing the contact point under the conventional type of Dynamic Active Antenna. We presents the basic working principle of SDAA and show some experimental result to verify the idea.
