Underwater Inspections using Remotely Operated Vehicles (ROV)

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ROV (Remotely Operated Vehicle) 

ROV (Remotely Operated Vehicle) is a tethered underwater vehicle/underwater robot which is submersible and can be used to conduct underwater inspections.ROVs can be utilized in challenging situations where diver-based inspections are quite difficult. ROV can be fitted with data capturing equipment, low light HD cameras, depth sensors, and altimeters which give a better idea about underwater objects.

Types of ROV

  • Work class ROV

Inspections can be conducted at greater depths using a work-class ROV. Inspections using work-class ROVs are typically conducted at depths where diver-based inspections are rather challenging.

  • Light Work Class ROV

At relatively shallow depths, this kind of ROV can be used.

  • Observation Class ROV

The observation class ROV is another name for the inspection class ROV. This class of ROV can support additional payloads and sensors.

  • Micro or Mini ROV

Micro or small ROVs are used at shallow depths. These ROVs are smaller than others of their kind.

EyeROV TUNA is an observation class ROV that goes up to a depth of 100m and gives you live HD videos. Its Dual HD camera gives a real-time view of the underwater structure to the user. With higher endurance provided by multiple batteries and a tether length of up to 300 m, it is the perfect ROV for demanding underwater inspections and operations. The TUNA ROV is also designed for carrying custom payloads as per the requirement of the operation having a range of attachments and sensors

EyeROV TURT, system is an electrically propelled, tethered underwater remotely operated vehicle (ROV), which is externally powered. The equipment has the capability to integrate various industrial payloads and an operational up-to-depth rating of 200m. The system is a custom modular ROV design with high-performance onboard computers and an intuitive control console for critical infrastructure inspection and surveillance operations.  The equipment is indigenously developed with enhanced control mode, high-intensity lights and HD cameras. The TURT ROV has 6 Degree’s of Freedom, making it highly maneuverable in challenging work environments. 

Key Operational parameters to know for choosing an ROV survey

  • Water current- is an important parameter which affects the ROV piloting

  • Turbidity-Due to turbidity, visibility may be poor thus the images obtained may be hazy and unclear. In such cases, imaging sonar can be included in the ROV.

  • Marine growth-May affect the visibility of the structure of interest for the ROV pilot and hence the purpose of the survey might be affected. In such extreme scenarios, appropriate cleaning payloads or penetrative radiations/waves-based payloads are to be accordingly chosen for the survey

  • Depth rating -An adequate depth rating is a necessary criteria in any underwater inspection. EyeROV TUNA has a 100 m depth rating and a tether length of 300m. EyeROV TURT has a depth rating of 300m.

  • Endurance/Portability/Operational Range-When light observation class ROVs are chosen there is always some trade off’s to be done between the endurance, portability and range of operations as they are interdependent. Light Portable ROVs are battery operated and they can have lightweight and very long-range tethers (up to 2km with Fiber optic tether), while their endurance is limited to a few hours. If externally powered is chosen then the range is only 300m  or less and the system gets bulkier as the Tether and reels get heavier and hence overall portability. These factors affect the full operations detrimentally and hence each unit is chosen wisely. 

ROV piloting

TUNA ROV is an externally powered (from Genset) underwater vehicle. The ROV is connected to the control station using special electrical cables(tether) for communication, data transfer and powering the vehicle. The ROV can be controlled from the control station through the Joystick. ROV carries multiple cameras and payloads and all the necessary sensors to execute the inspections effectively.

Execution methodology

EyeROV TUNA has full HD live streaming cameras and an additional static HD camera will be live streaming the surface/area of inspection and can continue inspection at pitch black darkness with its 6000+ Lumen lighting. ROV TUNA will dive from the water surface to the bottom using its powerful diving thrusters delivering powerful down thrust. A "LAWN MOWER" pattern parallel surveying dive lines with each line in the grid having 2 meters spacing and appropriately spaced from the wall surface for best visibility conditions will be executed. Measurements of dimensions of cavities, potholes and cracks will be done using LASER SCALAR onboard TUNA.

 All data will be live streamed by TUNA onto the control station display kept on the dam top. As and when required and as per the direction of the Engineer-In-Charge close-up views of defects can be easily photographed - as TUNA has advanced navigation and stabilisation controls.

Applications of ROV

Numerous industries, including aquaculture, infrastructure inspection, search and rescue operations, oil and gas, and others, can use ROVs for a wide range of purposes.

In aquaculture, ROVs are incredibly helpful for observing the life of marine creatures. It draws attention to the enormous changes in the underwater environment that affect marine life.

Inspection of undersea infrastructure is another important application for ROVs. The infrastructure below the water deteriorates over time, necessitating the inspection of underwater infrastructure.

Dams are a significant piece of underwater infrastructure that can be used for a variety of things, including irrigation, power generation, flood control, and the delivery of water for both domestic and commercial usage. Upstream and downstream parts make up a dam. Dams should be inspected at regular intervals to guarantee their safety.

Bridges offer ways to get across a barrier. Bridges should be regularly inspected and maintained to prevent the breakdown of these structures. The segment of the bridge that supports the entire structure is called the substructure. The components of a bridge's substructure that are present below the water line are vulnerable to destruction since they are hidden from view.

The complexity of SAR operations has decreased due to ROV innovation. The major limitations of diver-based SAR operations are water current and depth, but such scenarios can be avoided by employing an ROV. In diver-based search and rescue missions, both the safety of divers and the expense of such operations are important challenges. The best solution for SAR operations is a remotely operated vehicle (ROV), which is both affordable and less risky than diver-based examinations.

Another important industrial sector is oil and gas. The transfer of gas and oil in this industry is greatly aided by the use of pipelines. These pipes need to be handled with extreme caution because pipeline failure can have negative effects on both human life and the environment. Thus, pipeline maintenance and inspection are of utmost significance.