
Applied Acoustics (aae) understands that for companies in the dredging, offshore construction, and subsea exploration industries, working in the transition zone holds a distinctive series of challenges. Read more >>
Coastal areas are subject to constant wave action and fluctuating tides, accelerating wear on equipment and creating an environment where traditional subsea positioning systems may not perform adequately.
In response to these difficulties, Applied Acoustics has developed the MiniPod acoustic positioning system. Designed to function in dynamic conditions, it provides highly accurate positioning for vehicles, divers, and towed arrays when other methods, such as USBL, fall short.
The transition zone is a difficult operational environment for offshore activities, referring to the shallow area between dry land and navigable offshore waters. It is a region that traditional positioning technologies, like USBL or GNSS, struggle to cover effectively, as wave action and turbulent conditions disrupt standard methods.
Companies operating in this zone must contend with environmental forces that make cable laying, trenching, and dredging complex and dangerous.
The combination of wave forces, induced currents, and corrosion increases the operational risk for vessels and machinery. Furthermore, fluctuating tides that constantly reshape the seabed make precision critical if companies wish to avoid equipment damage or delays.
Key Challenges for Transition Zone Operations
The harsh environmental conditions in the transition zone intensify challenges for operations like dredging and trenching. Strong wave forces and unpredictable seabed conditions complicate the laying of subsea cables or foundations.
Positioning equipment becomes unreliable when subjected to violent wave action, necessitating constant recalibration and robust tools that can survive the conditions.
The accessibility and equipment strain caused by the shallow depth of the transition zone creates further difficulties. Equipment often struggles to navigate between surface and subsea operations, as water splash zones expose machinery to harsh conditions, reducing their longevity and accuracy.
Inconsistencies in positioning systems, like the acoustic USBL, typically results from issues with signal distortion in the transition zone, where temperature and salinity variations interfere with signal transmission.
Similarly, GNSS systems used for surface positioning can become unreliable due to vibrations caused by heavy machinery operations. Such environmental disturbances lead to jumps or inaccuracies in position readings, making precise operations harder to execute.
Limitations of Inertial Navigation Systems (INS), despite these normally offering another method of tracking movement, cause the systems to be vulnerable to vibration and drift over time. This sensitivity can lead to frequent recalibrations and inefficiencies during high-vibration activities, like excavation.
Without external corrections, such as those provided by GNSS-linked systems like the MiniPod, INS systems are not ideal for the transition zone’s harsh conditions.
Improving Operations with MiniPod Technology
Applied Acoustics’ MiniPod offers a solution designed specifically for the operational difficulties of the transition zone. The compact GNSS-enabled MiniPod system provides accurate real-time positioning for equipment and vehicles operating between the surface and subsea levels.
The MiniPod tracks dredging equipment and monitors subsea assets effectively, even in turbulent environments. Its quick signal acquisition times enable precise monitoring, improving safety during underwater installations and reducing downtime by offering continuous feedback on equipment location and status. The MiniPod’s key features include:
- Shock Resistance: The MiniPod’s internal and external shock mounts allow it to withstand the high-vibration environments typical of the transition zone. With a shock rating of up to 75G, it can endure tough conditions without losing accuracy.
- Precision Positioning: Both the 100 and 200 series MiniPods offer enhanced accuracy through dual GNSS configurations and LBand corrections. This flexibility allows operators to fine-tune positioning, even in environments where GPS alone may be unreliable.
- Deep Submersion Capability: The 106G MiniPod model is designed for immersion up to 6000m, making it ideal for deep-sea operations that require precision positioning upon surfacing. Its internal battery ensures that critical positioning systems remain operational, even in case of power failure, for up to an hour.
- Flexible Power Options: The MiniPod system supports various power configurations, allowing operators to hot-swap power packs for continuous operation, making it adaptable to long-duration projects in harsh environments.
The combination of advanced features provided by the MiniPod improves the safety and efficiency of offshore operations in the transition zone. By delivering precise positioning data and reducing operational downtime, the MiniPod system allows companies to navigate this challenging environment more effectively.
Furthermore, the ability to predict equipment wear and manage marine growth ensures that transition zone operations are both safer and more cost-effective. The MiniPod’s ability to streamline operations helps companies maintain tighter control over project timelines and budgets, preventing the risk of escalating costs.
Operating in the transition zone presents a series of complex challenges, from unpredictable environmental conditions to the difficulty of maintaining accurate positioning. Technologies like the MiniPod acoustic positioning system represent a significant advancement in mitigating these challenges.
With enhanced precision, robust design, and adaptability to harsh conditions, the MiniPod allows companies involved in dredging, cable laying, and offshore construction to work more safely and efficiently, helping to control costs and minimize risks in one of the most demanding operational environments.
Read the original article, or visit the aae website to find out more.