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Unmanned or manned underwater vehicles are often designed in cylindrical shapes which have desirable properties for withstanding the pressures that can be experienced in undersea environments. However, cylindrical designs are not required for non-pressurized enclosures. Non-cylindrical designs may provide benefits to developers including allowing a wider variety of materials for construction, greater...
Based on the current widespread use of underwater vehicles, a special type of underwater glider equipped with energy-saving diamond-structured rotatable wings that can improve the underwater vehicle's lift-drag ratio optimize hydrodynamic performance, and enhance flight quality was studied. With the support of adaptive meshing technology and Fluent's epsilon standard turbulence model, lift and drag...
The Atmospheric Diving Suit (ADS) has a longstanding history of use to aid in subsea construction, salvage, repair, platform inspection, oil and gas operations, and scientific purposes such as examining shipwrecks. The emergence of Remotely Operated Vehicle (ROV) technology, and other unmanned underwater vehicles, have begun to supplement the ADS in certain applications. However, due to the complex...
This paper introduces an underwater wheeled vehicle towing system which is composed of an anterior traction winch, a posterior brake winch, wire rope and fixed pulleys. Under the coordinate driving of two winches which one draw in the cable while another one let out the cable, the wheeled vehicle can be towed to achieve the accelerating, uniform speed and decelerating movement on the track which is...
In this study, virtual planar-motion-mechanism (PMM) tests in pure sway motion at constant forward speed are carried out to determine the sway added mass values of a 6:1 prolate spheroid. Added mass values are obtained by solving the Euler equations and the Reynolds Averaged Navier-Stokes (RANS) equations across a range of frequencies and depths. The effect that distance from the surface and radiation...
In this paper, the conceptual design with integrating motion control and considering the cross current was applied to establish a submarine motion simulator, where the path motion stability is evaluated. The methods used to construct the simulator include the standard navigation approach by applying the LOS algorithms and PD control Euler-Rodriguez quaternion for conversion between submarines motion...
There is a growing interest in the use of untethered underwater vehicles. These vehicles require robust and error-free underwater communication for transmission of mission-critical data. In contrast, the requirements for sensor payloads are often less stringent. Depending on the type of data, different Quality-of-Service (QoS) demands can be identified. To maximize the bandwidth utilization of underwater...
In this work, we present a bio-inspired fin prototype as a propulsion system for a submarine robot. We explain the rajiform locomotion, which is intended to be imitated with the movements of the fin. It is also explained how the undulations on the fin allow it to have different behaviors, thus generating thrust in different directions, which in turn generates several types of motion for the fin. Our...
Solar power plays a significant and sometimes primary role in the energy budgets of many terrestrial sensor systems due to its reliability, power density, and simplicity. More importantly, photoelectric generation can be accurately predicted for a given terrestrial location. This knowledge of expected harvested power is critical for both provisioning in design and scheduling of activities in operations...
The underwater vehicle-manipulator system (UVMS) generally has more degrees of freedom than those required to perform a given task. Because of these extra of degrees of freedom, UVMS has infinite combinations of joint velocities. In this paper, in order to generate the joint angle trajectories of the manipulator, a redundancy resolution is performed to minimize the distance between the position of...
This paper presents the motion simulation of an autonomous underwater helicopter (AUH), a new type of underwater vehicle proposed by Zhejiang University. In order to determine whether its controllability meets the design requirements, a singularity-free unit quaternion stable control method is used for simulating the AUH performance in MATLAB, including its force and trajectory under different types...
This paper combines FMEA and n2 approaches in order to create a methodology to determine risks associated with the components of an underwater system. This methodology is based on defining the risk level related to each one of the components and interfaces that belong to a complex underwater system. As far as the authors know, this approach has not been reported before. The resulting information from...
This paper addresses the time-optimal path planning problem for underwater vehicles in obstacle-constrained environments. It is assumed that the vehicles can move at variable speeds but their dynamics are subject to bounded curvature and turn rate. We present a novel pose-based search algorithm, which is a modified A∗ algorithm to find time-optimal paths between a given pair of vehicle poses including...
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