Published online by Cambridge University Press: 11 April 2006
The essential difference, from the theoretical point of view, between an externally excitedlciody and a fish is that the latter can apply lateral vibratory movements at any part of its surface, whereas in the ‘artificial fish’ lateral vibrations are applied only at the point where the external force acts on the body. A good example which illustrates how the artificial fish swims is the ‘Pod’. The Pod is a medical device consisting of a small magnet attached to a plastic ‘tail’. If the Pod is placed in a patient's blood vessel, and an alternating magnetic field is applied, the magnet oscillates angularly and the plastic tail causes it to swim. The purpose of the device is to deliver medicaments at any desired location in the circulatory system.
In this paper the theory of swimming of elastic slender bodies excited by an external force is presented. Special reference is made to the hydrodynamic forces acting on a swimming cylinder in viscous fluctuating flow. The results obtained are used in the analysis of the propulsion mechanism of the Pod.