10/28/2015hypack multibeam training seminar1 hycube hypack ® multibeam course

04/20/23 HYPACK Multibeam Training Seminar 1

HYCUBEHYCUBE

HYPACK ® MULTIBEAM COURSE

HYCUBE: HYCUBE: HYPACK’s Implementation of CUBEHYPACK’s Implementation of CUBE


CUBECUBE

CCombined ombined

UUncertainty and ncertainty and

BBathymetric athymetric

EEstimatorstimator

• Intended to Speed Processing of Multibeam Data.Intended to Speed Processing of Multibeam Data.• Developed by Developed by Dr. Brian Calder Dr. Brian Calder of CCOM-UNH.of CCOM-UNH.• A statistical approach to cleaning multibeam data.A statistical approach to cleaning multibeam data.


Introduction – the basicsIntroduction – the basics

04/20/23HYPACK Multibeam Training Seminar 4

Z-ValuesZ-Values UncertaintyUncertainty RatioRatio # of Hypotheses# of Hypotheses

HYSWEEPSURVEY

HSX MBMAX HS2 HYCUBE XYZ

CUBE TerminologyCUBE Terminology• CUBE Node:CUBE Node: An X-Y point where CUBE will make An X-Y point where CUBE will make

depth estimates based on the surrounding data depth estimates based on the surrounding data points.points.– CUBE Nodes are CUBE Nodes are ‘spaced’ ‘spaced’ at User Defined fixed distances, at User Defined fixed distances,

resulting in a square grid.resulting in a square grid.


CUBENodes

CUBENeighborhood

Data Points from HS2 File

CUBE TerminologyCUBE Terminology

• CUBE Neighborhood:CUBE Neighborhood: The area surrounding a CUBE The area surrounding a CUBE Node where depths can influence the ‘hypotheses’Node where depths can influence the ‘hypotheses’

• HYPOTHESIS:HYPOTHESIS: A possible depth estimate at a node. A possible depth estimate at a node.– A CUBE Node can have multiple ‘hypotheses’.A CUBE Node can have multiple ‘hypotheses’.

Note:

CUBE ‘hypotheses’ are not actual soundings, but are estimates of depth at each node, based upon the data points in the node’s neighborhood.


CUBENodes

CUBENeighborhood


Cube Grid and NeighborhoodsCube Grid and Neighborhoods

• A series of CUBE nodes make a CUBE GRID.A series of CUBE nodes make a CUBE GRID.• Soundings about the neighborhood of each node are used to generate Soundings about the neighborhood of each node are used to generate

depth estimates for the node (Hypotheses).depth estimates for the node (Hypotheses).• If there are multiple depth hypotheses at a node, CUBE selects its If there are multiple depth hypotheses at a node, CUBE selects its

best estimate of the depth.best estimate of the depth.


CUBENodes

CUBENeighborhood


First StepFirst Step


• Requires Minimal to No Pre-EditingRequires Minimal to No Pre-Editing

• Must be in HS2 format, so you must get to Phase 2 MBMAXMust be in HS2 format, so you must get to Phase 2 MBMAX

• Recommended that you Apply and Run some Filters in Phase 2 to Recommended that you Apply and Run some Filters in Phase 2 to minimize the amount of obvious ‘fliers’ or ‘spikes’ in the dataminimize the amount of obvious ‘fliers’ or ‘spikes’ in the data

• This will reduce the number of Hypotheses that CUBE will This will reduce the number of Hypotheses that CUBE will generategenerate

• Save to HS2 formatSave to HS2 format

HYSWEEPSURVEY

HSX MBMAX HS2 HYCUBE XYZ

HYCUBE Read ParametersHYCUBE Read Parameters


Node GenerationNode GenerationRead ParametersRead Parameters

• Node Spacing:Node Spacing:– User Defined DistanceUser Defined Distance between depth estimates. (In the Project’s distance units) between depth estimates. (In the Project’s distance units)– Originally, you had to have a minimum number of depths Originally, you had to have a minimum number of depths (11) (11) in a neighborhood in a neighborhood

in order to generate a CUBE estimate.in order to generate a CUBE estimate.

• Capture Distance:Capture Distance:– The ‘influence radius’ of a sounding is equal to the depth times the Capture The ‘influence radius’ of a sounding is equal to the depth times the Capture

Distance Scale percentage. Distance Scale percentage. – 5% seems to work well. (e.g. 10’ x 5% = 0.5’) 5% seems to work well. (e.g. 10’ x 5% = 0.5’)

• Median Length: (No Longer an Option)Median Length: (No Longer an Option)– The number of depths needed in a neighborhood in order to generate a CUBE The number of depths needed in a neighborhood in order to generate a CUBE

estimate. estimate. HYCUBE will use HYCUBE will use 11 sounding sounding, if that’s all that is available., if that’s all that is available.– Also used for the CUBE Median Filter (3 = weak; 11 = strong)Also used for the CUBE Median Filter (3 = weak; 11 = strong)


Disambiguation MethodDisambiguation MethodRead ParametersRead Parameters

• Disambiguation: Disambiguation: Method used by CUBE to select Method used by CUBE to select a depth hypothesis for a node when multiple a depth hypothesis for a node when multiple hypotheses exist.hypotheses exist.

– Prior: Prior: Selects the hypothesis represented by the most data points.Selects the hypothesis represented by the most data points.

– Likelyhood: Likelyhood: Searches for the nearest node with a single depth Searches for the nearest node with a single depth hypothesis and bases it’s select off that z-value. (hypothesis and bases it’s select off that z-value. (RecommendedRecommended))

– Posterior: Posterior: A combination of the above two methods.A combination of the above two methods.



New Hypothesis Window in 2011 Version

Running HYCUBERunning HYCUBE Select HS2 fileSelect HS2 file

(Single file or LOG file)(Single file or LOG file)

Select Select Configuration:Configuration: Sonar Type Sonar Type VesselVessel Error ModelError Model

Read ParametersRead Parameters Node SpacingNode Spacing Min/max depthMin/max depth Max angle (optional Max angle (optional

filters to use)filters to use)


Sonar DeviceSonar DeviceCUBE ConfigurationCUBE Configuration

• CUBE has error models CUBE has error models for some sonars.for some sonars.• This information improves This information improves

the TPU computation.the TPU computation.

• If your sonar is not listed:If your sonar is not listed:– Select ‘Not Listed’.Select ‘Not Listed’.


List of sonars with built-in error models in HYCUBE

Vessel SettingsVessel SettingsCUBE ConfigurationCUBE Configuration

• CUBECUBE uses the Vessel uses the Vessel Settings to assist in the Settings to assist in the computation of computation of TPUTPU..

• In HYPACK 2009, the In HYPACK 2009, the items are populated items are populated from the from the TPU EDITORTPU EDITOR..

• In previous versions, In previous versions, you had to enter your you had to enter your own values each time.own values each time.


Error ModelError ModelCUBE ConfigurationCUBE Configuration

• There are two error There are two error models that CUBE can models that CUBE can use when calculating use when calculating the TPU.the TPU.• Simple (IHO S-44)Simple (IHO S-44)• Full MBESFull MBES

• CUBECUBE will reject depths that will reject depths that have a have a TPUTPU above the above the specified specified Survey OrderSurvey Order


Cube Grid Cube Grid WindowWindow

• Displays CUBE Displays CUBE surfaces.surfaces.– Depth SurfaceDepth Surface

– UncertaintyUncertainty

– RatioRatio

– # of Hypotheses per # of Hypotheses per NodeNode

• New OpenGL New OpenGL improvements.improvements.

• Left-click to select Left-click to select node.node.


Depth SurfaceDepth SurfaceCUBE Grid WindowCUBE Grid Window

• Shows a 3D display of Shows a 3D display of CUBE Depth Surface.CUBE Depth Surface.

• Left-clickLeft-click to set cursor to set cursor position.position.– CUBE Node window CUBE Node window

updates to show updates to show distribution at selected distribution at selected node.node.

• Left-Click-and-dragLeft-Click-and-drag to to change viewing angles.change viewing angles.

• Right-clickRight-click to pan. to pan.


Uncertainty SurfaceUncertainty SurfaceCUBE Grid WindowCUBE Grid Window

• Useful for quality control.Useful for quality control.

• User can export an XYZ User can export an XYZ file where ‘z’ is the file where ‘z’ is the uncertainty for the depth uncertainty for the depth representing each node.representing each node.


RatioRatioCUBE Grid WindowCUBE Grid Window

• Useful for quality Useful for quality control.control.

• The lower the better….The lower the better….


• Ratio = 5 – [NS / ( NA – NS )] where

• NS = # depth samples in selected hypothesis and,

• NA = # depth samples in all hypotheses.

2 examples:

• GOOD: 40 depths in selected hypothesis, 10 in alternate,

5 – [40/(50-40)] -> Ratio = 1

• BAD: 10 depths in selected hypothesis, 40 in alternate,

5 – [10/(50-10)] -> Ratio = 4.75

Hypothesis CountHypothesis CountCUBE Grid WindowCUBE Grid Window

• Shows how many depth Shows how many depth estimates are generated estimates are generated at each node.at each node.


CUBE Node CUBE Node WindowWindow

• Displays:Displays:– Distribution of z-values in the Distribution of z-values in the

node’s neighborhood.node’s neighborhood.

– CUBECUBE Hypothesis ( Hypothesis (selectedselected) with ) with uncertainty boundaries.uncertainty boundaries.

• Modifies:Modifies:– Allows you to select an Allows you to select an

alternative hypothesis for a alternative hypothesis for a CUBE node.CUBE node.

• Searches:Searches:– Search for a CUBE node with Search for a CUBE node with

multiple hypotheses.multiple hypotheses.

– Select alternative hypothesis.Select alternative hypothesis.


Left-click on the alternate hypothesis to select it.

Save OptionsSave Options• Saves to XYZ file.Saves to XYZ file.

• Z can be: Z can be: – CUBE Depth EstimateCUBE Depth Estimate

– CUBE UncertaintyCUBE Uncertainty

– RatioRatio

– Hypothesis CountHypothesis Count

– Sounding Nearest CUBE Depth EstimateSounding Nearest CUBE Depth Estimate

• Adjustment:Adjustment:• Optionally adds or subtracts the Optionally adds or subtracts the

Uncertainly to/from the CUBE Depth.Uncertainly to/from the CUBE Depth.


Sample CUBE SessionSample CUBE Session

• Input: HS2 FilesInput: HS2 Files

• How much pre-editing How much pre-editing in MBMAX should you in MBMAX should you do?do?

– That’s a good That’s a good question…….question…….


Stats: Stats: CUBE Results vs. Reference SurfaceCUBE Results vs. Reference Surface

• Mean Difference: 0.02’ = 0.6 cm.Mean Difference: 0.02’ = 0.6 cm.

• Max Difference: 0.45’ = 13.7 cm.Max Difference: 0.45’ = 13.7 cm.

• 95% Confidence: 0.09’ = 2.7 cm.95% Confidence: 0.09’ = 2.7 cm.


Comparison: CUBE vs. Sort Min/MaxComparison: CUBE vs. Sort Min/Max


Green: Check Lines Processed in CUBE. Black: Reference Survey Sorted for Min and Max.

The HYCUBE surface usually resembles a smoother median surface.

10/28/2015hypack multibeam training seminar1 hycube hypack ® multibeam course

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