Presentation on theme: "Taking the Multibeam Jump"— Presentation transcript:
1 Taking the Multibeam Jump 2011 RESON User ConferenceTaking the Multibeam JumpA rough guide based on experiments with RESON multibeam echosoundersJean-Guy Nistad & Mathieu Rondeau
2 IntroductionExample of survey well suited for small enterprises: bridge pier mapping
3 IntroductionIntegrated (IMU + MBES), portable, pole-mounted solutions used on vessels of opportunityRESON Hydrobat(source: RESON)WASSP(source: ENL Electronic Navigation Ltd.
4 Introduction Problem: multibeam integration is complex Solution: share lessons from experiences with Seabat 7125 integrationThree requirements are of importance:Measure all relative locations and sensor orientationsBe aware of the sensor connection layoutAnticipate the data processing workflow
5 Lever arms & orientations Scenario 1X-3.512mPOS/MV 320XY-0.207mYZ-2.604m-1.835m-1.902m0.674m0.665mReference PointSeaBat 7125XY1.648mZ0.596m
6 Lever arms & orientations Defining the Ship Reference FrameX vesselZ vesselTPitch+Z vesselRRollY vessel+
7 Lever arms & orientations Scenario 2YXZ-0.658m-4.109m-0.895m-0.456m-0.975m0.275m-0.817mCentre of gravity
8 Lever arms & orientations Measuring the IMU mounting anglesY vesselAzHeadingX vessel+Z vesselTPitchX vessel+Y vesselZ vesselRRoll+
9 Lever arms & orientations Measuring the sonar mounting anglesY vessel+Heading30° starboard tiltX vesselAzZ vesselTPitchX vessel+RZ vesselRollY vessel+
10 Lever arms & orientations Incidence of 90° starboard rotation of the IMUX vessel+X IMUY IMUAzY vesselOnly detected with the 30° sonar tilt!
11 Lever arms & orientations Roll stabilization issue with 30° sonar tiltQuay side wallSeabed?Missed side wallNo roll stabilizationRoll stabilization
12 Lever arms & orientations Scenario 3Almost same as scenario 2Simulating an integrated pole-mounted systemFor integrated systems, IMU – MBES are factory aligned. How then should they relate to the SRF?
14 How does the chosen layout affect timing latency issues? Connection LayoutsMany different possible inter-sensor connection layoutsHow does the chosen layout affect timing latency issues?
15 Connection LayoutsFull serial (RS232, RS422) + Sonar PC+=
16 + = Connection Layouts Serial + USB between sonar and PC Processing Box
17 + = Connection Layouts Serial + LAN between sonar and PC Processing Box
18 + = Connection Layouts Serial + LAN between sonar and PC Processing Box
19 How does one solve for IMU latencies? Connection LayoutsLatencies will vary depending on chosen layoutThe conventional patch-test will solve for GPS – sonar latency but not IMU – sonar latency1 PPS is mistakenly seen as the ultimate solution to all latency issuesHow does one solve for IMU latencies?
20 Timing latencies Source: GeoSwath Plus Operation Manual Source: Lockhart, Arumugan, Precise Timing and TrueHeave® in Multibeam Acquisition and Processing
21 Data Processing Workflow PDS2000Raw bathymetryMore control in post-processing but harder to setupS7KPDSRESON Seabat 7125Corrected bathymetryEasier to setup but less control in post-processingQINSyCARISHIPS & SIPSXTFRESON Seabat 8101HypackHSX
22 RESON, Applanix, CARIS & QPS ConclusionOther helpful tips:Get familiar with standard hydrographic practicesGet friends in the Support department!Many thanks toRESON, Applanix, CARIS & QPS