  This paper presents preliminary results towards the development of an
autonomous ocean observing system using Miniature Underwater Gliders (MUGs)
that can operate with the support of Unmanned Aerial Vehicles (UAVs) and
Unmanned Surface Vessels (USVs) for deployment, recovery, battery charging, and
communication relay. The system reduces human intervention to the minimum,
revolutionizing the affordability of a broad range of surveillance and data
collection operations. The MUGs are equipped with a small Variable Buoyancy
System (VBS) composed of a gas filled piston and a linear actuator powered by
brushless DC motor and a rechargable lithium ion battery in an oil filled
flexible enclosure. By using a fully pressure tolerant electronic design the
aim is to reduce the total complexity, weight, and cost of the overall system.
A first prototype of the VBS was built and demonstrated in a small aquarium.
The electronic components were tested in a pressure testing facility to a
minimum of 20bar. Preliminary results are promising and future work will focus
on system and weight optimization, UAV deployment/recovery strategies, as well
as sea trials to an operating depth of 200m.
