A novel pulsatile jet propulsion scheme for low speed maneuvering of small underwater robots is developed, demonstrated, and characterized. This propulsion scheme is loosely analogous to that used by squid and jellyfish. The potential for pulsatile jet propulsion is explored by first optimizing the design of a pulsatile jet actuator and associated actuation concepts. Next, a vehicle-level fluid dynamical model is developed in order to capture the interaction of the pulsatile jet flows with the primary flow past the vehicle. Prior development in nonlinear averaging-based vehicle feedback control schemes is adapted to this technology using such models. The pulsatile jet prototypes and control scheme is integrated into a prototype underwater vehicle, whose performance is characterized. The suggested propulsion scheme has very few moving parts, has no protruding components that increase drag, and takes up relatively little volume.
Undergraduate engineering students are heavily involved in the design, fabrication, and testing of the pulsatile jet actuators and underwater vehicle prototypes proposed in this project. These activities provide excellent hands-on engineering experiences for the participating students.
