38 | Dredging and Port Construction | March 2013 dpcmagazine.com

feature: dredging and port software

One of the Smart Dredging Project partners (see DPC December 2012), IHS Systems "achieves efficiencies

with the help of sensors, programmable logic controllers (PLC), supervisory control and data acquisition systems (SCADA), model-based control software (MBC) and artificial intelligence (AI).

"This equipment, co-operating with inboard actuators and power systems, provides extra ‘eyes’ and ‘hands’ to operators, enabling them to optimise the production of their dredging vessels. Together with simulator utilisation, dredge track presentation and dynamic positioning/dynamic tracking systems (DP/DT), a modern dredger moves soil from and to accurately defined locations under tight tolerances, limiting costs and emissions".

Early developmentsSounds simple when put in a nutshell like the above, but the fact is technology's come a long way since the 1960s and 1970s when instrumentation such as vacuum meters replaced the intuitive process assessment of experienced operators and electro-hydraulic control began to require the application of relay technology.

"Gradually, more attention was paid to processes, requiring more instrumentation

such as pressure, density and velocity meters," an IHC Sysems spokesman explained. "The first attempts gave us tailored instrumentation – not very accurate, but robust enough to survive in the dredging environment. It had no counterpart in the common instrumentation industry – but it kept working and was vital for the then modest control and automation systems.

"More sophisticated instruments followed," he continued, "such as the radioactive mixture density meter and the inductive velocity meter, and in the 1980s and 1990s a balance was found between robustness and accuracy by combining industrial sensors with self-designed adaptations. Standardisation and accuracy became similar to that onshore".

Probably the decisive development was the PLC in the 1980s. First used for digital signals only, it enabled circuit schemes to be realised through easy programmable junctions instead of electrical wiring – a development that had an enormous impact on lead times and commissioning flexibility.

"PLCs opened the way to communication with computers," the spokesman noted. "In only 10 years computer capacity exploded and PCs and industrial standards were introduced, allowing the first SCADA systems to emerge

Dredge smart, dredge efficient!Efficient dredging – from sensor to artificial intelligence – is the stated focus and mission of IHC Systems

aboard dredgers, eventually developing into large-scale use of hardware and software platforms, with the benefits of worldwide availability. Together with modern sensors, they shape today's reliable control, automation and presentation systems".

Driving towards the futureIHC Systems’ application of AI and MBC means "it's now approaching ‘immeasurable’ values online," the spokesman said, "as well as the verification and temporary replacement of signals by ‘dead reckoning’. Control systems can now be informed with parameters not previously available, such as the estimated forces in a TSHD’s suction pipe(s) during dredging for DP/DT information, or the average grain size to aid intricate pumping processes. As well as making vulnerable sensors superfluous, benefits include accuracy and production improvements.

"These adaptive self-learning systems can be developed and tested in practice, using real-time simulators, primarily invented to test sophisticated control circuits. These are increasingly adopted by leading dredging contractors for training crew and staff".

Finally…There are two challenges engineers still face, the spokesman concluded: "AI and MBC applications look promising, but bringing them to maturity, with consequent efficiency improvements, is the first challenge.

"Second is a tendency towards total integration of systems’ software and hardware – alarm monitoring, propulsion control, power management, and platform control. With collaboration by IHC Drives & Automation, such a system exists on Shanti Sagar XV, an IHC Merwede-built 13,000kW cutter suction dredger. More dredgers will follow!"

» www.ihcsystems.com

The efficient dredging concept provides additional ‘eyes’ and ‘hands’ to operators Royal Boskalis

DP/DT strongly benefits from artificial intelligenceIHC Merwede