Advantages of Using Combined Bathymetry and Side Scan Data in Survey Processing T.M. Hiller, L.N. Brisson EdgeTech, West WareHam MA, USA
EdgeTech 6205 Combined Bathymetric and Side Scan Sonar
EdgeTech s Next Generation MPES Bathymetric Technology Coverage of up to 10 x water depth. IHO Special Order compliant coverage over 9x water depth Over 200⁰ Swath Coverage Co-registered Dual Frequency Side Scan Imagery High Resolution Superior Data Quality & Integrity
Technology Summary : EdgeTech 6205 Multi-Phase Echo Sounder (MPES) technology Typical Multibeam Footprint Swath up to 10 x water depth, and IHO SO to up to 9 x water depth. 200⁰ field of view Typical 6205 Footprint Two Bathymetric frequency Options 230 khz, longer range 540 khz, higher resolution Integrated, Co-registered Dual Frequency Side Scan Imagery
Swath bathymetry systems utilize two differing technologies to achieve bathymetry measurements across a swath of the sea floor: Beam Forming (MBES) Interferometric Sonars MPES combines MBES and Interferometry to improve nadir performance and multipath rejection, while maintaining a wide swath
EdgeTech s Next Generation MPES Bathymetric Technology 6205 Swath Bathymetry and Side Scan System Port and Starboard transducers: 10 bathy receive staves per side Chirp pulses for higher accuracy and extended range Full nadir coverage Improved Multipath and Wake Suppression Total field of view is over 200 degrees Integrated dual frequency side scan
Frequency Options The 6205 is available in several standard frequency configurations: 230 khz Bathymetry : to 215m depth below transducers 230 & 550 khz Dual Frequency Side Scan 550 khz Bathymetry :to 75m depth 230 & 550 khz Dual Frequency Side Scan 550 khz Bathymetry 550 & 1600 khz Dual Frequency Side Scan The modular design of the 6205 also allows for multi-frequency bathymetry options with field exchangeable array design for survey operations in both shallow and deep water operations.
Side Scan Sonar : Real Ranges Frequency Range 230 khz 150 to 300m 540 khz 100 to 150m 1600 khz 30 to 35m Shallow water (< 30m) Range may be limited by noise from surface reflections, channel effects etc.
Three types of data available - Bathymetry - Backscatter - Sidescan (Dual Frequency)
Aim Show the overall system performance Wide Swath and coverage at Nadir Use IHO S44 5 th Ed. Special Order as a standard Methodology Create a Reference Surface Multiple lines, in various directions, over the same area Run a test line and compare to that Reference Surface Results Demonstrates Wide Swath Coverage Demonstrates Compliance at Nadir
Reference Surface St. John s River, Jacksonville, FL, USA Approximate Water Depth = 10 m The reference surface was acquired using 200% coverage with a boustrophedonic lattice pattern, consisting of 16 N-S lines and 16 E-W lines, and only logging the highest quality data, or 90 deg swath. Support Sensors Applanix POS MV Trimble HPD450 Radio Real-time kinematic (RTK) Average surface looks clean and noise free.
EdgeTech 6205 test line differenced from a reference surface Approximate Depth = 10 m Results Error bars show 95% confidence level
Data Resolution retained at Nadir Circles are made by Clam Dredgers Cross Section Shown Depth of these scours is about 5cm 20 cm
Cross Section Shown Data Resolution retained at Nadir
Wide Swath Data: New River, bank-to-bank
Advantages of Co-Registered Bathymetry & Side Scan - Improved understanding of data during survey - Significantly aids data processing and filtering - Enhances object detection - Improved feature definition and interpretation - Improves interpretation of shoal features - Improved interpretation of complex areas - Complementary information for identifying bottom type
Fish Shadows Spikes Fish
Improved Data Cleaning with the Aid of SS Imagery - Wakes
Sidescan helps identification of shoal features
Additional information for Object Detection and Identification
Co-Registered Bathymetry & Side Scan aids Object Interpretation
Bathymetry and Co-registered Side Scan aids Pipeline Surveys The Great Lakes Research Center (GLRC) at Michigan Technological University, deployed an OceanServer Iver AUV with an EdgeTech 2205 combined Side Scan Sonar and Bathymetry system with the goal of imaging an underwater pipeline. Side scan sonar and bathymetry images were used to check the location and integrity of the pipeline over a long and varied terrain. Using side scan sonar coregistered with bathymetry the team was able to view intricate details about the pipeline and the bottom topography, helping accomplish their mission.
Co-Registered Bathymetry & Side Scan improves interpretationof of debris field
Improved interpretation of complex areas: 550kHz Bathymetry and Side Scan of Dock Entrance
Data Interpretation with the Aid of SS Imagery Bottom features
Data Interpretation with the Aid of SS Imagery Bottom Types 100m
Data Interpretation with the Aid of SS Imagery Bottom types Eel Grass Side Scan & Co-Registered Bathymetry Water Depth less than 1 meter at Chart Datum
Advantages of Using Combined Bathymetry and Side Scan Data in Survey Processing T.M. Hiller, L.N. Brisson EdgeTech, West WareHam MA, USA