In the subsequent years, technological advancements in sensors, computers, and control systems propelled the evolution of DP systems, giving captains complete control of the position and heading of their vessels, even in the most trying of weather conditions.
At the most basic level, the concept and operation of a DP system hasn’t changed, with thrusters used to counteract external forces and keep the vessel at the desired position or path. However, recent leaps made in these technologies have enhanced safety and performance offshore.
Tech on the Horizon
While traditional measurements of wind speed and direction have proven beneficial to the industry, real-time sea state measurements of waves and currents are still only applied to a limited degree.
A reluctance to embrace these technologies is to the detriment of efficient and safe offshore operations.
Advancements in wave and vessel motion prediction have the potential to revolutionize the offshore industry. It enables the exciting ability to envisage what is likely to happen ahead of time and will be a major boon to the maritime and energy sectors.
Headway has been made to turn this concept into a reality, but wave prediction is still in its early stages, and there is a need to educate the sector on how it works. Waves are stochastic; they are random and variable, so while they can be analyzed out of sight, they can’t be predicted with absolute certainty. In other words, it is impossible to know the specifics of a wave that has not been seen.
Predicting future waves can be separated into two broad categories: statistical and deterministic. Statistical prediction uses up-to-the-minute information to build a better understanding of the forecasted wave conditions, including probable maximum wave heights in a given period in the range of minutes to hours or days.
Deterministic prediction covers the use of advanced analytics and artificial intelligence (AI) from a combination of radar sources in real time for exact information to monitor and track specific waves and predict their impact in the range of seconds to minutes, giving offshore personnel advanced warning that a big wave is approaching.
Caution is Key
Once this prediction technology is installed on vessels it can support DP operations, which rely on accurate and short-term information to maintain their position, especially during critical operations such as subsea construction, installation, deployment or retrieval of equipment, or underwater inspections.
(Image credit: Miros)
In the sea state monitoring industry, deterministic prediction is the Holy Grail and is repeatedly discussed. However, as is always the case when deploying any technological advancements, caution is key. Operators planning to use existing sea-state measurements or coming wave prediction technology should be prepared to spend time becoming familiar with the applications and understanding the reliability of the measurements. There are several steps to take and added value to gain before vessel operators can reach the ultimate ambition of ‘automatic control’.
Evaluating if the weather forecast is in line with the actual weather conditions is vital, and data from well-proven sea state measurements can feed into offline planning and simulation tools. From there, the technology can non-intrusively improve visual sea state awareness for the crew on the bridge. It is clearly beneficial to simply look out of the window or check the forecast.
The next and more integrated technology use is around DP consequence analysis; sea state information is measured at the vessel’s specific location and applied to estimate corresponding environmental forces acting on the vessel. Rather than relying on forecasts, this gives a better way to assess whether operations can continue safely if a failure happens. Should these previous steps have proved successful, the prediction of incoming waves or vessel response can inform manual action, such as holding back on specific operations, firing up thrusters, or adjusting position.
Looking Forward
The pinnacle for wave prediction technology would be for the sector to reach a level where measurements directly and automatically feed into the DP control system, as is done today for wind sensors. In this situation, the system would foresee a four-meter wave hitting at a near- specific point in time and reacting without human input.
minimizing risks.
That doesn’t mean to say that at some point in the future, vessels will be self-operating. Airplanes still require pilots to monitor the systems, even if the autopilot is used for most of a flight. It’s a similar principle here.
Wave prediction technology is all about making people’s jobs easier and improving decision-making in a tough and changing environment, with the overarching aim of minimizing risk.
The industry also should not lose sight of the journey and steps that need to be taken to reach this ultimate aim of automated control.
Looking forward, there is considerable value still to be realized, value that can greatly improve the efficiency, accuracy, and safety of offshore operations. As we mark four decades as a pioneer in marine technology,
Miros remains committed to helping the sector use the information at its fingertips to stay ahead of the wave.
To find out more, visit: www.miros-group.com
This feature appeared in environment coastal & offshore (eco) magazine’s 2024 winter edition Ocean Enterprise, to read more access the magazine here.
