What is the present reality?
Historically, ADCPs have been sold with ‘core’ firmware that provides the basic ability to measure water currents. More sophisticated features such as wave or turbulence characterisation come as additional capability.
This method of providing new or upgraded features is detrimental to customer operations: Such features are guided by commercial development decisions made by the ADCP supplier and are thus beyond the control of any individual customer. Further, the customer has little or no choice in the method of implementation, which may be enforced by patent laws as each supplier seeks to protect their intellectual property. These restrictions potentially result in sub-optimal performance.
What is the Sonardyne solution?
Origin circumvents these problems by supporting Sonardyne’s Edge computing environment. In much the same way as apps can be installed on a smartphone, Edge applications can be installed on an Origin ADCP to enhance the capability of the instrument by implementing custom algorithms suitable for particular applications.
All Edge apps work in a similar way and are defined as either file‑based applications, or live (packet-based) applications, depending on the type of data they ingest. As Origin captures data according to its programmed measurement schedule, it produces files or live packets of data.
File apps process input files of data (such as PD0 format files) into a different output format, such as comma-separated variable (csv) format which can be read into a spreadsheet. The output files are typically much smaller than the input file. File apps are normally used in Origin ‘Endurance’ operations, where extending battery life is more important than near real‑time decision making.
By contrast, live apps process individual ensemble data as it is captured. This mode of operation is better for deployments where rapid feedback on the environmental properties is more important than battery conservation. A live app may simply look for a particular feature in the data and send an alarm when a certain criterion is met.
What Edge apps are available?
A selection of Sonardyne Edge apps are available for download and use with your Origin ADCP. What’s nice is that once a deployment is over, an app can be switched out for another, providing you with measurement flexibility to meet changing operational requirements.
A simple Edge app example is the Background Currents app appropriate for Origin 600 and Origin 65. This app computes the mean background current over a time interval, and either logs the data to disk, or exports it acoustically in near real‑time. Certain processing parameters (such as averaging window) can be modified in situ via custom commands issued acoustically to Origin. This allows customers to change the behaviour of the installed application without the need to change any of the code or issue a feature request to the supplier.
Another app appropriate for use with both the Origin 600 and Origin 65, is the QARTOD QC app. This app computes quality metrics of ADCP data, including velocity magnitude, echo intensity and rate of change of tilts.
For Origin 600, there are also some more sophisticated Edge apps, such as Waves and Turbulence apps.
The Waves Edge app processes data as it is collected by Origin and calculates a directional cross‑spectrum. The cross‑spectrum can be logged to disk for inspection after the device is recovered or exported live through Origin’s integrated acoustic modem for near real‑time monitoring of the waves.
The turbulence app measures turbulence kinetic energy (TKE) production and dissipation. This calculates production and dissipation metrics over a burst of measurements using standard algorithms. Similar to the Waves app, the results can be logged to disk for later inspection or transmitted live to the water surface acoustically.
Installing or changing Edge applications can be performed when cabled to Origin via the devices’ embedded Web UI, or acoustically using the Origin Topside software. This allows for maximum in‑field customisation that does not require costly retrieval of Origin; certain apps can be installed, used, deleted, and a different app installed while the device is on the seabed
To find out more about Edge computing, the SDK and the apps being made available by Sonardyne, check out videos on our YouTube channel.
Contact [email protected] for more information.