When we first started our quarterly newsletters a year ago, our goal was to keep our clients updated, showing off the work done at Chesapeake and giving a preview of some new areas that are in development. It was also our way of staying in touch with our clients. Since last March, we all have been caught up in the Covid pandemic and became somewhat isolated – and for the majority, we found ourselves at home in front of a computer screen. At some point soon, we will get back to the travels, to see folks in 3D and not in 2D, and to enjoy each other’s company.

For now, welcome to our Q1 2021 edition of the Chesapeake Times.

In this edition, you will read about the features in our upcoming release of SonarWiz, version 7.7.5. This version is currently in testing and our anticipated release date is April 28th. There are over 60 updates and changes added, from sidescan to sub bottom, single beam and multibeam. With the release out, the team will focus on completing the work on the globalization of the software, among other new tools and features.

Recently, I tried something new here at Chesapeake and assigned each of us to become a subject matter expert in one area of SonarWiz. I took on the single beam world – something all of us used at some point in our careers. Single beam is just a small part of the SonarWiz package, but it is becoming a more powerful tool for our users, as it leverages all the tools of SonarWiz for acquisition and processing. You will see my article on the work we have done to the servers and processing tools.

This quarter, we delivered the full topside solution for the GeoAcoustic Geopulse compact and Pulsar sidescan. Working with Richard Dowdeswell and his team, our new servers will handle all the command and control for these sonars – simplifying the user experience with a single topside solution. Read more about it in Patrick’s article.

Check out our website, as we continue to update and add news features, including videos of our recent webinars. We also have information on our next training event, to be held in June (virtually).

Someone famous once said – “If you’re not the lead dog, the scenery doesn’t change”. Our goal here at Chesapeake is to continue to lead, with innovation and features, working with clients to meet their needs. When explaining the quote to my daughter, she did not understand it, and simply asked, why can’t you turn your head and look in another direction?

She is still learning the meaning of a metaphor.

Which Way Is Up? - Plan View Rotation ........................ Jonathan Fleetwood, Engineer

Updates to Gains in 7.07.05....................................... David Finlayson, Chief Scientist

New SonarWiz Splash Screen................................... Christopher Favreau, CTO

New Advances in SonarWiz Single Beam.................. Harold Orlinsky, General Mgr

GeoAcoustics partnership for PulSAR & GeoPulse.... Patrick Zynda, Support Engr

North-up has until recently been the only plan view orientation available in SonarWiz. Views other than the main plan view - the external helm display and the 3D viewer - have been able to orient to the current survey line or vessel, but the plan view has always remained north-up.

A recent release of SonarWiz includes as a new feature the ability to rotate the main plan view itself. This allows for easy orientation to a user-specified heading, the current steering line, or actual vessel heading. Real-time collection benefits the most from this; SonarWiz can now make it easier to follow planned lines and ensure good coverage without the overhead of managing other programs and windows, especially with the help of the L/R steering indicator:

In the 2D Map Display section of the View ribbon tab, note the additions of a Compass Rose checkbox and an Orientation drop-down:

The Compass Rose checkbox in the ribbon displays a compass rose in the top right corner of the plan view to make its orientation apparent. It's a four-pointed design with one red point indicating zero, with a textual indicator in the center denoting the heading at the top of the screen. Tick marks are arranged at 30 degree intervals.

The Orientation drop-down offers quick switching between three modes: user-specified, ship up, and line up. Switching into any of these modes directly in the drop-down will switch to that mode, and apply it if/when it becomes applicable.

User-specified at 315 degrees:

Oriented to the currently-selected steering line:

Oriented to a vessel recording some simulated bathymetry data:

User-specified mode is applied by default at program startup with a zero heading, replicating north-up. Switching into this mode from either of the other two via the drop-down will snap the plan view back to its prior user-specified orientation. Ship-up and line-up orient the plan view to the currently active vessel or currently-selected steering survey line, if any.

The Settings entry at the bottom of the Orientation menu will allow for providing parameters to the user-specified and ship-up modes. User-specified mode allows for entering a heading value to place at the top of the plan view. Ship-up mode offers a threshold; incoming navigation headings differing from the current plan view orientation by more than this threshold will trigger a rotation.

Until recently, most sidescan and sub-bottom customers were mainly interested in producing beautiful imagery. The specific intensity values were not interesting so long as the relative image was sharp and well defined. SonarWiz gain algorithms were originally developed to make relative changes to the ping intensity values. Gains could be stacked, and if too much gain was applied to a portion of a ping such that it overflowed, rather than clipping the data, the algorithms were designed to rescale or normalize the data so that the whole dynamic range was compressed to fit the display. It was possible to apply gains---even unreasonable gains---and yet still produce an image that looked ok.

EGN was originally designed so that all files in a survey are added to a single EGN table and the user interface in SonarWiz was designed to support this. However, under some survey conditions, building a new EGN table for each track line produces better results. In this mode, you are using EGN much like beam angle correction. In prior versions of SonarWiz, creating a new table for each file was a tedious manual process. In SonarWiz 7.05.05, we’ve added a new check box to the table creation dialog that will automatically create and assign a new EGN table for every file in the project if desired.

The second new option for EGN is the surfacing of a table smoothing parameter. EGN correction tables are stored by beam angle and range. The correction for each sample is determined by interpolation on the EGN table. We found that in some cases, neighboring nodes in the table of corrections were sensitive to outliers and this would result in along-track stripes in the processed data. Smoothing the correction table reduces the artifact significantly. But, as with all things, sometimes smoothing introduces artifacts of its own. By allowing advanced users to control the smoothing or even to turn it off entirely, EGN will work well on more data sets.

If you are interested in learning more about SonarWiz gain algorithms, we recently gave an in depth webinar on each of the available algorithms. You can watch the webinar on YouTube: Cocoa with CTI: Sidescan Gain Settings

The New SonarWiz Splash Screen

Single beam sonars are like the middle child – always there, but never given much attention. An easy-to-use system, to set up and to process data, and widely used around the world in hydrography, and always forgotten. Here at Chesapeake, we decided to give it its 15 minutes of fame and spent time last quarter updating the program with new tools and features, enhanced our servers. We worked with manufactures to capture and process their full stream of data. Two systems in place now are the Teledyne Odom E20 and the Kongsberg EA440

When the work started, we had a few goals in mind: Full control of the sonar – without the need for other software. Nothing wrong with manufacture’s software, but if SonarWiz can do all the controls, no need to have it run alongside. Secondly, store the data in industry format, so anyone can use it. Of course, processing in SonarWiz would be great, but we did not want to restrict anyone from using other software. Depth is stored in XTF, sidescan in XTF and sub-bottom in SegY. (note - the last two are not typically considered “single beam”, but these systems are sending more than just depth data). Lastly, store the manufacture’s own file format. It is a bit of a redundancy, but if we are to replace the manufacture’s software, we need to make the same type of file. On the processing side, be able to handle the full datagram from the manufacture’s own format. In the case of the E20, it is their s7k, and the EA440, it is their RAW file.

SonarWiz has all the tools already developed for multibeam, and leveraged off using them for processing single beam data. Some of the tools for cleaning the data include the swath editor, tides, sound velocity, and RTK tides using external navigation. SonarWiz also added in a beam performance test to validate and ensure the system meets a certain criterion. Tools needed for a final product - Sounding export, with frequency options, tools for gridding and contouring, plus all the tools already in SonarWiz – export to KML, coverage reports, etc. can all be done.

Processing the acoustic datagram, SonarWiz uses the sub bottom tools for this data. Although these single beam systems are not a traditional sub bottom system, the datagram provides data from the water column to the sub surface – giving the user more information to use for the analysis. Stored as a SegY file, the data is imported into the program seamlessly and allows the user the tools of sub-bottom – digitizing acoustic reflectors, measuring thickness, marking contacts. The EA440 also has transducers to generate sidescan imagery. Processing of this data imagery data uses the SonarWiz tools for sidescan mosaicking.

As we continue our work on the single beam module, we will be adding in new sensors and formats. Keep an eye on the server for new additions to the program.

Chesapeake Technology is excited to announce a partnership with GeoAcoustics Ltd to provide users a complete survey solution, combining hardware and software for a seamless operation of sidescan and sub bottom sonar systems.

All purchased PulSAR Sidescan and GeoPulse Compact Sub Bottom sonars will come with the complete SonarWiz data acquisition package. Customers will be provided with a special version of the SonarWiz installer that already includes the real time server needed and unlike other servers that can only simply read information being broadcast from the system, it can be operated without the need for any additional software. Full control of the sonar settings – including power, gain, ping rate and more, are handled in the SonarWiz software.

While collecting data, customers will have full access to SonarWiz’s powerful real-time capabilities with waterfall displays, navigation, and signal processing. The data will be recorded in a raw file format (XTF and SEGY) as well as SonarWiz’s internal file format (CSF).

For any customers using these systems, our sales team would like to offer a free evaluation of the programs post processing capabilities which would provide you with a full survey solution from fish to Geotiff!

Join CTI this June for a three day virtual training on post processing of sidescan, sub bottom, bathymetry and magnetometer data. It will be held June 9-11 from 10:00am - 6:00pm EST. We may also include a half day or more about real time data collection with SonarWiz, date to be announced.

Partnering with Kongsberg Mesotech on Wednesday, May 12, we'll be hosting a webinar demonstrating SonarWiz and the M3 FLS import, functionality and processing.

We will be back at Mesotech for onsite or virtual training for two days, September 28-29. Finally we have tentatively scheduled our Annual Winter training workshop for Dec 7 - 9 at the College of Charleston. Stay tuned for further details. 

Over the past year, we drastically increased individualized training sessions. These are completely customizable and are especially convenient, as customers are able to keep a recorded copy of the class to share or watch again. This is especially helpful for our users worldwide who can review and train during their normal business hours. We are also offering hybrid training options with a mix of recorded and live custom training. Please contact us to schedule.

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