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Published in Cheng Siong Chin, ™, 2020
The demand for remotely operated vehicles (ROVs) [1] has increased extensively over the years due to their ability to carry out a search operation in environments that are beyond human capabilities. With advanced technologies, these underwater vehicles can travel more than 3000 m deep into the ocean for pipeline inspection and cable laying, making them a valuable asset for the offshore industry. The ROV controlled by a pilot on board a vessel relies on limited data received from underwater sensors. Hence, operating the ROV in an uncertain underwater environment is quite challenging for novice pilots who have little experience and knowledge. Moreover, it puts the ROV and surrounding equipment and environment at a higher risk [2]. Although a high level of skills is required for operating the ROV, pilot training is still conducted on-the-job basis [3]. A safe alternative to using a simulated-based pilot training system [3–5] was used. Based on the ROV mission requirements, various operating conditions and vehicle configurations can be constructed in the virtual world [6–7]. Pilot trainees can pick up skills and knowledge in a safe, conducive and low-pressure learning environment assisted with training guides [8].
Controllability studies on fish-shaped unmanned under water vehicle undergoing manoeuvring motions
Published in Petar Georgiev, C. Guedes Soares, Sustainable Development and Innovations in Marine Technologies, 2019
A. K. Ranjith, S. Janardhanan, V. Chandran, N. J. Gomez, G. Ilieva, J. Sygal
In ostraciiform models, the undulation is confined mostly to the caudal fin without moving the body. The thrust for this model is generated with a lift-based method, allowing cruising speeds to be maintained for long periods. This form is considered to be the simplest of all for carrying out mathematical studies. A UUV with hull form geometrically similar to that of a box-fish, a typical ostraciiform model undergoing manoeuvring motions in heave and pitch, has been analysed for controllability in the present study. UUVs also known as underwater drones are vehicles with no humans onboard during the course of their mission. There are basically two types of UUVs-autonomous underwater vehicle (AUV) and remotely operated vehicle (ROV). AUVs are more or less like robots not entailing human intervention throughout their mission while ROVs are remotely operated from a ground station.
Oceans: Observation and Prediction
Published in Yeqiao Wang, Atmosphere and Climate, 2020
Oscar Schofield, Josh Kohut, Grace Saba, Xu Yi, John Wilkin, Scott Glenn
Propeller-driven autonomous underwater vehicles (AUVs) are powered by batteries or fuel cells and can operate in water as deep as 6000 m. Similar to gliders, AUVs relay data and mission information to shore via satellite. Between position fixes and for precise maneuvering, inertial navigation systems are often available onboard the AUV to measure the acceleration of the vehicle, and combined with Doppler velocity measurements, it is used to measure the rate of travel. A pressure sensor measures the vertical
Data-driven approach for uncertainty quantification and risk analysis of composite cylindrical shells for underwater vehicles
Published in Mechanics of Advanced Materials and Structures, 2023
Ming Chen, Xinhu Zhang, Guang Pan
Composite materials are extensively applied in aerospace, aircraft, automobile and civil engineering because of their excellent properties [1–3]. In recent years, more and more underwater vehicles have been manufactured using composite materials because of their unique properties such as ultra-high strength, light weight, and resistance against corrosion [4–6]. Traditionally, the hulls of underwater vehicles are made of metallic materials such as high-strength steel, aluminum and titanium alloys. However, the buoyancy-to-weight ratio and load-carrying capacity of these hulls are relatively low [7, 8]. An effective measure is to substitute metallic materials with composite materials, making the hull lighter and increasing the load-carrying capacity [9]. In this way, the flexibility and payload of an underwater vehicle can be greatly improved.
Design, development, and control of a tough electrohydraulic hexapod robot for subsea operations
Published in Advanced Robotics, 2018
I. Davliakos, I. Roditis, K. Lika, Ch.-M. Breki, E. Papadopoulos
Underwater robots are employed in a number of scientific, exploration, commercial, and military tasks. Underwater robots include Remotely Operated Vehicles (ROVs) or Autonomous Underwater Vehicles (AUVs). Although these can be used in underwater repairs and exploration, they cannot be used in tasks on the seabed or shores, such as laying cables. Legged, tracked, or even wheeled underwater robots can be used as subsea explorers or navigators and for operations such as trenching. However, underwater tracked and wheeled vehicles cannot operate over rough, slopped, or discontinuous terrain, as they can become unstable easily [3]. Because of their ability to lift their legs over obstacles, place them in a range of discontinuous stance points, and change the main body position and attitude by adjusting leg configuration, subsea legged robots can be more stable than other types of robots, rejecting environmental disturbances from sea currents, slopes, etc.