Towards automated substrate mapping with low-cost sidescan sonar

2nd Multibeam in Rivers Workshop, Flagstaff, AZ

Transcript

1. Towards automated substrate mapping with low-cost sidescan sonar Daniel Buscombe, GCMRC-USGS MBES in Rivers Workshop Flagstaff, AZ, March 2015
3. 10cm transducer
4. Starboard scans Colorado River in Grand Canyon
5. Penobscot River, Maine
6. 30 miles of Marble Canyon in 2013 30 miles of Eastern Grand Canyon in 2014 Several reaches in Glen and Marble Canyons repeat mapped 2013 - 2015
8. w = cos (θ) = ℎ For given h, shadow length w increases as decreases θ = sin Assuming h constant over small window: Step 1: calculate w for each window Step 2: remove bias in w caused by sonar geometry Object height h and shadow length w are related by: w = w π/2 sin−1(c/tf) w = w dx
9. RM30 Marble Canyon Colorado River Preliminary data – do not cite
10. RM61 Marble Canyon Colorado River Preliminary data – do not cite
11. Dog River, Mobile May, Alabama. Credit: Allen Aven, Dauphin Island Sea Lab 200 kHz echosounder: full waveform 1st echo 2nd echo Chap 3.1-3.2, Penrose et al. (2005) “Acoustic Techniques for Seabed Classification” RoxAnn
12. ‘Roughness’ ‘Hardness’ Volume scattering coefficients K=3 means acoustic ‘classes’ Preliminary data – do not cite
13. Glen Canyon Substrate/Vegetation Mapping Lasers spaced 9cm
14. Glen Canyon Vegetation/substrate Mapping ‘Roughness’ ‘Hardness’ 3 acoustic classes Preliminary data – do not cite
15. PyHum (Beta) software Collaborations/data welcome!!! https://pypi.python.org/pypi/PyHum pip install PyHum https://github.com/dbuscombe-usgs/PyHum git clone https://github.com/dbuscombe-usgs/PyHum.git
16. Thanks! • Paul Grams, Ted Melis, Mike Yard: GCMRC • Sean Smith: U Maine • Dan Hamill, Joe Wheaton: USU • Allen Avery: Dauphin Island Sea Lab Upper Granite Gorge, Colorado River, May 2014
17. Upper Marble Canyon, May 2012