Testing a pneumatic underwater glider in shallow water

In this paper we discuss the testing of a novel underwater glider designed to be fast and maneuverable for operation in the littorals. The glider´s pneumatic buoyancy engine was shown to operate reliably and provide large, rapid displacements. However, the compressibility of the bladder and associated change in tank weight (from exhausting air with each dive) presented significant challenges in trimming the vehicle. Several design considerations unique to a glider with unlimited roll control (and a cylindrical moving mass actuator) were identified through testing. The performance of a long baseline acoustic positioning system was characterized, and the challenges associated with deploying this system in a shallow-water, rocky-bottom lake are discussed.