The Mantaro ROV was designed and built by ASI Group in the early 1990s to support the inspection of a 20-km-long intake tunnel transporting water from the Mantaro River at the Tablachaca Dam to the Santiago Antúnez de Mayolo Hydroelectric Plant (SAM), still considered the largest hydroelectric plant in Peru. The project involved collecting data to evaluate the tunnel’s condition, including its diameter and any significant debris accumulation.
“The Mantaro ROV was a work in progress, with reliability and capability improvements made in almost every subsequent project,” noted Bob Clarke, Vice President of Research and Development at ASI Group. He further mentioned that no vehicle previously existed that could cover the necessary distance for a fully remote inspection. This required designing and building a vehicle equipped with an optical fiber umbilical to transmit control and sensor signals over long distances.
This project marked a significant milestone in the development and use of ROVs for underwater inspections.
Technological Comparison: How Has ROV Technology Evolved from the First Mission to Today?
The technology first used in the Mantaro ROV not only evolved but also became obsolete after many years of use. Analog sensors and controls have been replaced with digital ones, which are much easier to integrate, consume less power, and are more robust. Today, most control and data acquisition systems are computer-based, relying on software to process commands and signals.
Navigation and Positioning Systems Have Become More Affordable
“From the basic umbilical deployment originally used to determine distance traveled along the tunnel, we now use inertial navigation systems (INS) to pinpoint exact world coordinates in XYZ. With multiplexed digital signals and control software, there are more opportunities to alert conflicts, errors, and failures.”
– Bob Clarke, ASI Group
ASI Group now operates an extensive fleet of ROV equipment for various requirements and conditions. Among them, the Mohican ROV stands out, modified by ASI with umbilicals of 14, 12, and 10 km in length. Using this vehicle, ASI has broken several world records, including the longest penetration of a tunnel (over 13 km in 2018) and a new depth record of over 600 meters inside a pressurized tunnel leading to a hydroelectric unit. Some of these records have earned international recognition, including Guinness World Records for the longest single penetration of a flooded tunnel using an ROV and the longest flooded tunnel survey using an ROV, both repeatedly surpassed by ASI over the years.
How Has ROV Evolution Changed the Focus and Efficiency of Underwater Inspections?
The digitization of controls and sensors has facilitated the integration of new technology and peripherals, allowing for increasingly precise inspections in adverse conditions. Propulsion technology and vehicle design have also improved drastically, enhancing reliability and efficiency.
Bob Clarke also highlights the importance of proper technology use and ongoing workforce development, emphasizing that ROV inspections achieve their full potential only with experienced and trained personnel.
“It’s not just the advancement of technology but also the progress in working with a team of people that makes any ROV operation successful. Without a comprehensive understanding of the technology, its capabilities, and limitations, investing in expensive equipment alone will not lead to a high-quality outcome.”
– Bob Clarke, ASI Group
This has translated into clear benefits for companies adopting this technology. Tangible advantages include shorter inspection times (less downtime), the ability to inspect structures without draining, and the capacity to inspect areas never previously accessible.
We are global leaders in underwater operations! Contact us to collaborate on your project.
