Using light underwater : devices, algorithms and systems for maritime persistent surveillance

This thesis presents a novel approach to long-term marine data collection and monitoring. Long-term marine data collection is a key component for understanding planetary scale physical processes and for studying and understanding marine life. Marine monitoring is an important activity for border protection, port security and offshore oil field operations. However, monitoring is not easy because salt water is a harsh environment for humans and for instruments. Radio communication and remote sensing are difficult below ocean surface. Our approach to ocean data collection relies on the integration of (1) a network of underwater sensor nodes with acoustic and optical communication, (2) an autonomous underwater vehicle (AUV) and (3) a novel sensing device. A key characteristic is the extensive use of visible light for information transfer underwater. We use light for sensing, communication and control. We envision a system composed of sensor nodes that are deployed at static locations for data collection. Using acoustic signaling and pairwise ranging the sensor nodes can compute their positions (self-localize) and track mobile objects (e.g., AUVs). The AUV can visit the sensor nodes periodically and download their data using the high speed, low power optical communication. One consequence of using optical communication for the bulk of the data transfer is that less data needs to be transferred over the acoustic links, thus enabling the use of low power, low data rate techniques. For navigation, the AUV can rely on the tracking information provided by the sensor network. In addition, the AUV can dock and transport sensor nodes efficiently, enabling their autonomous relocation and recovery. The main application of our system is coral reef ecosystem research and health monitoring.

Department dc:contributor.department

Massachusetts Institute of Technology. Dept. of Electrical Engineering and Computer Science.

Grantor dc:publisher

Massachusetts Institute of Technology

Year dc:date.issued

2009

Author dc:creator

• Vasilescu, Iuliu

Advisor dc:contributor.advisor

• Daniela Rus.

• Electrical Engineering and Computer Science.

Statement dc:rights

• M.I.T. theses are protected by copyright. They may be viewed from this source for any purpose, but reproduction or distribution in any format is prohibited without written permission. See provided URL for inquiries about permission.

Licence dc:rights.uri

• http://dspace.mit.edu/handle/1721.1/7582

Language dc:language.iso

eng

Handle dc:identifier.uri

http://hdl.handle.net/1721.1/46790

OAI identifier oai:identifier

oai:dspace.mit.edu:1721.1/46790