Please wait, while we are loading the content...
Please wait, while we are loading the content...
Content Provider | IEEE Xplore Digital Library |
---|---|
Author | Chotiros, N.P. Isakson, M.J. Piper, J.N. McNeese, A. |
Copyright Year | 2014 |
Description | Author affiliation: Appl. Res. Labs., Univ. of Texas at Austin, Austin, TX, USA (Chotiros, N.P.; Isakson, M.J.; Piper, J.N.; McNeese, A.) |
Abstract | Improvements to a method of seafloor roughness measurement using low-power lasers and a video recorder mounted on a remotely operated vehicle (ROV) are presented. The platform is a Saab Seaeye Falcon observation class ROV. Six green laser beams are spread into illuminated planes using gratings or cylindrical lenses. The intersection of the laser planes with the ocean bottom was imaged on a high-definition digital video recorder at an oblique angle. After correcting for aberrations due to refraction between air and water and other imperfections, the three-dimensional coordinates of the laser profiles relative to the video recorder are computed for each video frame. This is a low-cost device, since the laser modules are commercial line generator modules of moderate power output. Green lasers were chosen for their low attenuation in seawater. The power output of each laser module was chosen to be within the Class 3R designation to avoid the permitting issues of high power lasers, although high power units are being developed. The lasers are housed within an optically clear acrylic tube. In addition to the laser modules, a light-emitting diode (LED) white light source is also deployed within the laser housing to provide background illumination of the seabed around the laser lines. The digital video recorder is a high definition consumer-grade device, housed in a separate tube with a clear acrylic window. Power is provided by the ROV. The signal and controls are carried by one shielded twisted pair cable through the ROV umbilical to the shipboard control unit. Auxiliary data include roll, pitch and heading information are simultaneously recorded. Ultra short baseline (USBL) acoustic positioning information from the ROV is also recorded. In previous experiments, the laser planes were arranged in parallel, but in the current configuration some laser planes are rotated to intersect with the others. The intersections present additional difficulties for the automatic tracing and identifying software, but they provide a number of advantages in calibration and position tracking. |
Starting Page | 1 |
Ending Page | 4 |
File Size | 1104388 |
Page Count | 4 |
File Format | |
e-ISBN | 9781479936465 |
DOI | 10.1109/OCEANS-TAIPEI.2014.6964504 |
Language | English |
Publisher | Institute of Electrical and Electronics Engineers, Inc. (IEEE) |
Publisher Date | 2014-04-07 |
Publisher Place | Taiwan |
Access Restriction | Subscribed |
Rights Holder | Institute of Electrical and Electronics Engineers, Inc. (IEEE) |
Subject Keyword | Measurement by laser beam Correlation Semiconductor lasers Sea measurements Laser modes Laser beams ROV laser profiling roughness wavenumber spectrum seabed |
Content Type | Text |
Resource Type | Article |
National Digital Library of India (NDLI) is a virtual repository of learning resources which is not just a repository with search/browse facilities but provides a host of services for the learner community. It is sponsored and mentored by Ministry of Education, Government of India, through its National Mission on Education through Information and Communication Technology (NMEICT). Filtered and federated searching is employed to facilitate focused searching so that learners can find the right resource with least effort and in minimum time. NDLI provides user group-specific services such as Examination Preparatory for School and College students and job aspirants. Services for Researchers and general learners are also provided. NDLI is designed to hold content of any language and provides interface support for 10 most widely used Indian languages. It is built to provide support for all academic levels including researchers and life-long learners, all disciplines, all popular forms of access devices and differently-abled learners. It is designed to enable people to learn and prepare from best practices from all over the world and to facilitate researchers to perform inter-linked exploration from multiple sources. It is developed, operated and maintained from Indian Institute of Technology Kharagpur.
Learn more about this project from here.
NDLI is a conglomeration of freely available or institutionally contributed or donated or publisher managed contents. Almost all these contents are hosted and accessed from respective sources. The responsibility for authenticity, relevance, completeness, accuracy, reliability and suitability of these contents rests with the respective organization and NDLI has no responsibility or liability for these. Every effort is made to keep the NDLI portal up and running smoothly unless there are some unavoidable technical issues.
Ministry of Education, through its National Mission on Education through Information and Communication Technology (NMEICT), has sponsored and funded the National Digital Library of India (NDLI) project.
Sl. | Authority | Responsibilities | Communication Details |
---|---|---|---|
1 | Ministry of Education (GoI), Department of Higher Education |
Sanctioning Authority | https://www.education.gov.in/ict-initiatives |
2 | Indian Institute of Technology Kharagpur | Host Institute of the Project: The host institute of the project is responsible for providing infrastructure support and hosting the project | https://www.iitkgp.ac.in |
3 | National Digital Library of India Office, Indian Institute of Technology Kharagpur | The administrative and infrastructural headquarters of the project | Dr. B. Sutradhar bsutra@ndl.gov.in |
4 | Project PI / Joint PI | Principal Investigator and Joint Principal Investigators of the project |
Dr. B. Sutradhar bsutra@ndl.gov.in Prof. Saswat Chakrabarti will be added soon |
5 | Website/Portal (Helpdesk) | Queries regarding NDLI and its services | support@ndl.gov.in |
6 | Contents and Copyright Issues | Queries related to content curation and copyright issues | content@ndl.gov.in |
7 | National Digital Library of India Club (NDLI Club) | Queries related to NDLI Club formation, support, user awareness program, seminar/symposium, collaboration, social media, promotion, and outreach | clubsupport@ndl.gov.in |
8 | Digital Preservation Centre (DPC) | Assistance with digitizing and archiving copyright-free printed books | dpc@ndl.gov.in |
9 | IDR Setup or Support | Queries related to establishment and support of Institutional Digital Repository (IDR) and IDR workshops | idr@ndl.gov.in |
Loading...
|