Autonomous Docking Demonstrations with Enhanced REMUS Technology

As autonomous underwater vehicles (AUV's) become more pervasive and enter common usage, systems that expand their capabilities, extend their range, and/or permit operation in denied areas become essential. A dock is one method of achieving these goals. An autonomous dock for an AUV provides the capability to greatly increase the duration and extent of AUV operations, provided the dock has a substantially greater energy supply than the AUV. Other docking station applications include the possibility of installation onto a cabled oceanographic observatory, thus providing unlimited power for battery recharge and continuous data communications. This paper presents the design, development, testing, and results of recent field demonstrations of a compact bottom-mounted docking station for a modified REMUS-100 series AUV. In addition to the dock development, the REMUS vehicle was enhanced with a new, modular endcap to facilitate the installation of modular sensors to the vehicle for the docking program. These sensors include a new digital ultra-short baseline (USBL) acoustic homing array and a periscope camera for sea-surface observations. The USBL homing array along with DVL velocity and altitude information provided the capability of the AUV to reliably navigate along a pre-programmed glidepath into an entrance nozzle of the dock. A unique challenge of this second generation docking system was the requirement for small size and near-bottom entrance into the dock.