Design and evolution of a piezoelectrically actuated miniature swimming vehicle

Abstract

This work details the design of a miniature swimming vehicle that propels itself through oscillations of a flexible fin mounted in the stern. The fin is driven through a mechanism that is actuated by two curved-beam bending piezoelectric actuators. An optimization routine is used to design the mechanism for rigid body guidance. The actuators are modeled statically using the Bernoulli-Euler method. Hamilton's principle is applied to the actuators and, by employing the modal analysis, a dynamic actuator model is developed and compared to experimental data. The physical evolution of the swimming vehicle is discussed, and a prototype for an on-board digital control circuit is evaluated. The latest vehicle design, which incorporates on-board digital control, is presented in terms of its design and experimentally determined the performance characteristics. The current swimming vehicle prototype achieves fish-like maneuvering and an approximate velocity of 0.25 m/s.