1. HYPACK Multibeam Training Seminar
HYCUBE
HYPACK ® MULTIBEAM COURSE
4/24/2017
HYPACK Multibeam Training Seminar

2. HYCUBE: HYPACK’s Implementation of CUBE
4/24/2017
HYPACK Multibeam Training Seminar

3. HYPACK Multibeam Training Seminar
CUBE
Combined
Uncertainty and
Bathymetric
Estimator
Intended to Speed Processing of Multibeam Data.
Developed by Dr. Brian Calder of CCOM-UNH.
A statistical approach to cleaning multibeam data.
4/24/2017
HYPACK Multibeam Training Seminar

4. Introduction – the basics
HYSWEEP
SURVEY
MBMAX
HYCUBE
HSX
HS2
XYZ
Z-Values
Uncertainty
Ratio
# of Hypotheses
HYPACK Multibeam Training Seminar
4/24/2017

5. HYPACK Multibeam Training Seminar
CUBE Terminology
CUBE Node: An X-Y point where CUBE will make depth estimates based on the surrounding data points.
CUBE Nodes are ‘spaced’ at User Defined fixed distances, resulting in a square grid.
CUBE
Nodes
Neighborhood
Data Points from HS2 File
HYPACK Multibeam Training Seminar
4/24/2017

6. HYPACK Multibeam Training Seminar
CUBE Terminology
CUBE
Nodes
Neighborhood
Data Points from HS2 File
CUBE Neighborhood: The area surrounding a CUBE Node where depths can influence the ‘hypotheses’
HYPOTHESIS: A possible depth estimate at a node.
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.
HYPACK Multibeam Training Seminar
4/24/2017

7. Cube Grid and Neighborhoods
Nodes
Neighborhood
Data Points from HS2 File
A series of CUBE nodes make a CUBE GRID.
Soundings about the neighborhood of each node are used to generate depth estimates for the node (Hypotheses).
If there are multiple depth hypotheses at a node, CUBE selects its best estimate of the depth.
HYPACK Multibeam Training Seminar
4/24/2017

8. HYPACK Multibeam Training Seminar
First Step
HYSWEEP
SURVEY
HSX
MBMAX
HS2
HYCUBE
XYZ
Requires Minimal to No Pre-Editing
Must be in HS2 format, so you must get to Phase 2 MBMAX
Recommended that you Apply and Run some Filters in Phase 2 to minimize the amount of obvious ‘fliers’ or ‘spikes’ in the data
This will reduce the number of Hypotheses that CUBE will generate
Save to HS2 format
HYPACK Multibeam Training Seminar
4/24/2017

9. HYCUBE Read Parameters
HYPACK Multibeam Training Seminar
4/24/2017

10. Node Generation Read Parameters
Node Spacing:
User Defined Distance between depth estimates. (In the Project’s distance units)
Originally, you had to have a minimum number of depths (11) in a neighborhood in order to generate a CUBE estimate.
Capture Distance:
The ‘influence radius’ of a sounding is equal to the depth times the Capture Distance Scale percentage.
5% seems to work well. (e.g. 10’ x 5% = 0.5’)
Median Length: (No Longer an Option)
The number of depths needed in a neighborhood in order to generate a CUBE estimate. HYCUBE will use 1 sounding, if that’s all that is available.
Also used for the CUBE Median Filter (3 = weak; 11 = strong)
HYPACK Multibeam Training Seminar
4/24/2017

11. Disambiguation Method Read Parameters
Disambiguation: Method used by CUBE to select a depth hypothesis for a node when multiple hypotheses exist.
Prior: Selects the hypothesis represented by the most data points.
Likelyhood: Searches for the nearest node with a single depth hypothesis and bases it’s select off that z-value. (Recommended)
Posterior: A combination of the above two methods.
HYPACK Multibeam Training Seminar
4/24/2017

12. HYPACK Multibeam Training Seminar
New Hypothesis Window in 2011 Version
4/24/2017
HYPACK Multibeam Training Seminar

13. HYPACK Multibeam Training Seminar
Running HYCUBE
Select HS2 file
(Single file or LOG file)
Select Configuration:
Sonar Type
Vessel
Error Model
Read Parameters
Node Spacing
Min/max depth
Max angle (optional filters to use)
4/24/2017
HYPACK Multibeam Training Seminar

14. Sonar Device CUBE Configuration
CUBE has error models for some sonars.
This information improves the TPU computation.
If your sonar is not listed:
Select ‘Not Listed’.
List of sonars with built-in error models in HYCUBE
4/24/2017
HYPACK Multibeam Training Seminar

15. Vessel Settings CUBE Configuration
CUBE uses the Vessel Settings to assist in the computation of TPU.
In HYPACK 2009, the items are populated from the TPU EDITOR.
In previous versions, you had to enter your own values each time.
4/24/2017
HYPACK Multibeam Training Seminar

16. Error Model CUBE Configuration
There are two error models that CUBE can use when calculating the TPU.
Simple (IHO S-44)
Full MBES
CUBE will reject depths that have a TPU above the specified Survey Order
4/24/2017
HYPACK Multibeam Training Seminar

17. HYPACK Multibeam Training Seminar
Cube Grid Window
Displays CUBE surfaces.
Depth Surface
Uncertainty
Ratio
# of Hypotheses per Node
New OpenGL improvements.
Left-click to select node.
4/24/2017
HYPACK Multibeam Training Seminar

18. Depth Surface CUBE Grid Window
Shows a 3D display of CUBE Depth Surface.
Left-click to set cursor position.
CUBE Node window updates to show distribution at selected node.
Left-Click-and-drag to change viewing angles.
Right-click to pan.
4/24/2017
HYPACK Multibeam Training Seminar

19. Uncertainty Surface CUBE Grid Window
Useful for quality control.
User can export an XYZ file where ‘z’ is the uncertainty for the depth representing each node.
4/24/2017
HYPACK Multibeam Training Seminar

20. HYPACK Multibeam Training Seminar
Ratio CUBE Grid Window
Useful for quality control.
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
4/24/2017
HYPACK Multibeam Training Seminar

21. Hypothesis Count CUBE Grid Window
Shows how many depth estimates are generated at each node.
4/24/2017
HYPACK Multibeam Training Seminar

22. HYPACK Multibeam Training Seminar
CUBE Node Window
Displays:
Distribution of z-values in the node’s neighborhood.
CUBE Hypothesis (selected) with uncertainty boundaries.
Modifies:
Allows you to select an alternative hypothesis for a CUBE node.
Searches:
Search for a CUBE node with multiple hypotheses.
Select alternative hypothesis.
Left-click on the alternate hypothesis to select it.
4/24/2017
HYPACK Multibeam Training Seminar

23. HYPACK Multibeam Training Seminar
Save Options
Saves to XYZ file.
Z can be:
CUBE Depth Estimate
CUBE Uncertainty
Ratio
Hypothesis Count
Sounding Nearest CUBE Depth Estimate
Adjustment:
Optionally adds or subtracts the Uncertainly to/from the CUBE Depth.
HYPACK Multibeam Training Seminar
4/24/2017

24. HYPACK Multibeam Training Seminar
Sample CUBE Session
Input: HS2 Files
How much pre-editing in MBMAX should you do?
That’s a good question…….
HYPACK Multibeam Training Seminar
4/24/2017

25. Stats: CUBE Results vs. Reference Surface
Mean Difference: 0.02’ = 0.6 cm.
Max Difference: 0.45’ = 13.7 cm.
95% Confidence: 0.09’ = 2.7 cm.
4/24/2017
HYPACK Multibeam Training Seminar

26. Comparison: 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.
4/24/2017
HYPACK Multibeam Training Seminar