Taking the Multibeam Jump 2011 RESON User Conference Taking the Multibeam Jump A rough guide based on experiments with RESON multibeam echosounders Jean-Guy Nistad & Mathieu Rondeau

Introduction Example of survey well suited for small enterprises: bridge pier mapping

Introduction Integrated (IMU + MBES), portable, pole-mounted solutions used on vessels of opportunity RESON Hydrobat (source: RESON) WASSP (source: ENL Electronic Navigation Ltd.

Introduction Problem: multibeam integration is complex Solution: share lessons from experiences with Seabat 7125 integration Three requirements are of importance: Measure all relative locations and sensor orientations Be aware of the sensor connection layout Anticipate the data processing workflow

Lever arms & orientations Scenario 1 X -3.512m POS/MV 320 X Y -0.207m Y Z -2.604m -1.835m -1.902m 0.674m 0.665m Reference Point SeaBat 7125 X Y 1.648m Z 0.596m

Lever arms & orientations Defining the Ship Reference Frame X vessel Z vessel T Pitch + Z vessel R Roll Y vessel +

Lever arms & orientations Scenario 2 Y X Z -0.658m -4.109m -0.895m -0.456m -0.975m 0.275m -0.817m Centre of gravity

Lever arms & orientations Measuring the IMU mounting angles Y vessel Az Heading X vessel + Z vessel T Pitch X vessel + Y vessel Z vessel R Roll +

Lever arms & orientations Measuring the sonar mounting angles Y vessel + Heading 30° starboard tilt X vessel Az Z vessel T Pitch X vessel + R Z vessel Roll Y vessel +

Lever arms & orientations Incidence of 90° starboard rotation of the IMU X vessel + X IMU Y IMU Az Y vessel Only detected with the 30° sonar tilt!

Lever arms & orientations Roll stabilization issue with 30° sonar tilt Quay side wall Seabed ? Missed side wall No roll stabilization Roll stabilization

Lever arms & orientations Scenario 3 Almost same as scenario 2 Simulating an integrated pole-mounted system For integrated systems, IMU – MBES are factory aligned. How then should they relate to the SRF?

Lever arms & orientations Scenario 3 + Heading Y sonar Az X sonar + Z sonar Pitch T X sonar Z sonar + Roll R Y sonar

How does the chosen layout affect timing latency issues? Connection Layouts Many different possible inter-sensor connection layouts How does the chosen layout affect timing latency issues?

Connection Layouts Full serial (RS232, RS422) + Sonar PC + =

+ = Connection Layouts Serial + USB between sonar and PC Processing Box

+ = Connection Layouts Serial + LAN between sonar and PC Processing Box

+ = Connection Layouts Serial + LAN between sonar and PC Processing Box

How does one solve for IMU latencies? Connection Layouts Latencies will vary depending on chosen layout The conventional patch-test will solve for GPS – sonar latency but not IMU – sonar latency 1 PPS is mistakenly seen as the ultimate solution to all latency issues How does one solve for IMU latencies?

Timing latencies Source: GeoSwath Plus Operation Manual Source: Lockhart, Arumugan, Precise Timing and TrueHeave® in Multibeam Acquisition and Processing

Data Processing Workflow PDS2000 Raw bathymetry More control in post-processing but harder to setup S7KPDS RESON Seabat 7125 Corrected bathymetry Easier to setup but less control in post-processing QINSy CARIS HIPS & SIPS XTF RESON Seabat 8101 Hypack HSX

RESON, Applanix, CARIS & QPS Conclusion Other helpful tips: Get familiar with standard hydrographic practices Get friends in the Support department! Many thanks to RESON, Applanix, CARIS & QPS