Toward a compact underwater structured light 3-D imaging system

A compact underwater 3-D imaging system based on the principles of structured light was created for classroom demonstration and laboratory research purposes. The 3-D scanner design was based on research by the Hackengineer team at Rice University. The system is comprised of a low-power, open-source hardware single-board computer running a modified Linux distribution with OpenCV libraries, a DLP pico projector, camera board, and battery module with advanced power management. The system was designed to be low-cost, compact, and portable, while satisfying requirements for watertightness. Future development and applications may involve navigation systems for an autonomous underwater vehicle (AUV). An initial study of 3-D imaging methods is presented, and the strengths and drawbacks of each type are discussed. The structured light method was selected for further study for its ability to produce high-resolution 3-D images for a reasonable cost. The build of the 3-D imaging system was documented for reproducibility, and subsequent testing demonstrated its functions and ability to produce 3-D images. An instruction guide for operation of the device is provided for future classroom and laboratory use. The 3-D imaging system serves as a proof-of-concept for utilizing structured light methods to produce 3-D images underwater. Image resolution was limited by the output resolution of the pico projector and camera module. Further exploration in obtaining ultra high-resolution 3-D images may include use of a more powerful projector and a higher resolution camera board module with autofocus. Satisfactory 3-D scanning validated the performance of structured light scanning above water. However, contaminants in the water hindered accurate rendering by the system while submerged due to light scattering. Future development of a on-the-fly mapmaking system for AUV navigation should include algorithms for filtering light scattering, and hardware should based on an instantaneous structured light system utilizing the Kinect 2-D pattern method. Autofocus and increased projector brightness would also be worthwhile additions.

Department dc:contributor.department

Massachusetts Institute of Technology. Department of Mechanical Engineering.

Grantor dc:publisher

Massachusetts Institute of Technology

Year dc:date.issued

2013

Author dc:creator

• Dawson, Geoffrey E

Advisor dc:contributor.advisor

• John J. Leonard.

• Mechanical Engineering.

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/1721.1/83705

OAI identifier oai:identifier

oai:dspace.mit.edu:1721.1/83705