Spelling suggestions: "subject:"remote operated vehicles""
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The prediction of hydrodynamic drag for ROVs with appendagesPedret, Benjamin G. January 1988 (has links)
No description available.
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Hydrodynamic aspects of ROV designBaker, J. H. A. January 1989 (has links)
No description available.
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Applying Technology of Virtual Reality to the Navigation of Remotely Operated VehiclesHung, Chia-Hui 24 August 2001 (has links)
When evaluating the benefits of the artificial reefs, the generally is performed by sending divers or using Remotely Operated Vehicles (ROV). But to do the observation work, the deep sea is too dangerous for human being to work longer time, and ROV has no capable navigation system. So underwater survey became difficulty. The thesis integrates LXT Tracking System, Global Positioning System, Motion Sensor, Gyro Compass and the ROV original sensors such as : pressure sensor and magnetic compass to resolve the navigation problem of ROV, together with the high-density data of Multibeam echo sounder to rebuild the status of the seabed and artificial reefs. The thesis tries to apply the technology of Virtual Reality (VR) in ROV to being the interface. The results demonstrate the VR interface can display the position of ROV in three-dimensional space actually. And it can show the position of ROV navigation and warning message in real time when sailing. So the VR Navigation System will improve the ability of operating ROV greatly.
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Programming by demonstration for dual-arm manipulationMudgal, Karan Chaitanya 28 May 2024 (has links)
Motivated by challenges operators face with manual control tasks, including fatigue and workload management, this research explores the adoption of a semi-autonomous control method to improve work environment quality and task metrics in controlled situations. Building upon the success of Programming by Demonstration (PbD) for single-arm industrial robotic applications, we extend these techniques to dual-arm robotic control. We present a semi-autonomous approach allowing users to supervise tasks while delegating control to the system, alleviating stress and fatigue associated with manual control operations. This research compares manual and semi-autonomous control in a human-robot team, focusing quantitatively on user performance and qualitatively on trust in the system. Participants controlled a dual-arm robotic system from a remote cockpit, monitoring progress through a graphical user interface (GUI) and camera views. Semi-autonomous control employs PbD with selectable ’motion primitives’. Trials involved a modified pick-and-place task and results demonstrate a significantly higher success rate across all metrics with semi-autonomous control.
This study highlights the applicability of PbD as a semi-autonomous control method in human-robot teams, reducing workload stress and enhancing task performance. Integrating sensors for dynamic environment analysis to create motion feedback mechanisms could further enhance user trust and system adaptability. Ultimately, this research suggests implementing semi-autonomous control for dual-arm robotic systems, offering faster onboarding for new operators and increased operational flexibility while minimizing user stress and fatigue.
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Video sequence analysis for subsea roboticsPlakas, Konstantinos January 2001 (has links)
No description available.
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Coordinated control of small, remotely operated and submerged vehicle-manipulator systemsSoylu, Serdar 20 December 2011 (has links)
Current submerged science projects such as VENUS and NEPTUNE have revealed the
need for small, low-cost and easily deployed underwater remotely operated vehiclemanipulator
(ROVM) systems. Unfortunately, existing small remotely operated
underwater vehicles (ROV) are not equipped to complete the complex and interactive
submerged tasks required for these projects. Therefore, this thesis is aimed at adapting a
popular small ROV into a ROVM that is capable of low-cost and time-efficient
underwater manipulation. To realize this objective, the coordinated control of ROVM
systems is required, which, in the context of this research, is defined as the collection of
hardware and software that provides advanced functionalities to small ROVM systems.
In light of this, the primary focus of this dissertation is to propose various technical
building blocks that ultimately lead to the realization of such a coordinated control
system for small ROVMs.
To develop such a coordinated control of ROVM systems, it is proposed that ROV and
manipulator motion be coordinated optimally and intelligently. With coordination, the
system becomes redundant: there are more degrees of freedom (DOF) than required.
Hence, the extra DOFs can be used to achieve secondary objectives in addition to the
primary end-effector following task with a redundancy resolution scheme. This
eliminates the standard practice of holding the ROV stationary during a task and
uncovers significant potential in the small ROVM platform.
In the proposed scheme, the ROV and manipulator motion is first coordinated such that
singular configurations of the manipulator are avoided, and hence dexterous manipulation
is ensured. This is done by using the ROV's mobility in an optimal, coordinated manner.
Later, to accommodate a more comprehensive set of secondary objectives, a fuzzy
based approach is proposed. The method considers the human pilot as the main operator
and the fuzzy machine as an artificial assistant pilot that dynamically prioritizes the
secondary objectives and then determines the optimal motion.
Several model-based control methodologies are proposed for small ROV/ROVM
systems to realize the desired motion produced by the redundancy resolution, including
an adaptive sliding-mode control, an upper bound adaptive sliding-mode control with
adaptive PID layer, and an H∞ sliding-mode control. For the unified system (redundancy
resolution and controller), a new human-machine interface (HMI) is designed that can
facilitate the coordinated control of ROVM systems. This HMI involves a 6-DOF
parallel joystick, and a 3-D visual display and a graphical user interface (GUI) that
enables a human pilot to smoothly interact with the ROVM systems. Hardware-in-theloop
simulations are carried out to evaluate the performance of the coordination schemes.
On the thrust allocation side, a novel fault-tolerant thrust allocation scheme is proposed
to distribute forces and moments commanded by the controller over the thrusters. The
method utilizes the redundancy in the thruster layout of ROVM systems. The proposed
scheme minimizes the largest component of the thrust vector instead of the two-norm,
and hence provides better manoeuvrability.
In the first phase of implementation, a small inspection-class ROV, a Saab-Seaeye
Falcon™ ROV, is adopted. To improve the navigation, a navigation skid is designed that
contains a Doppler Velocity Log, a compass, an inertial measurement unit, and acoustic
position data. The sensor data is blended using an Extended Kalman Filter. The
developed ROV system uses the upper bound adaptive sliding-mode control with
adaptive PID layer.
The theoretical and practical results illustrate that the proposed tools can transform, a
small, low-cost ROVM system into a highly capable, time-efficient system that can
complete complex subsea tasks. / Graduate
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Influence of seasonally variable hypoxia on epibenthic communities in a coastal ecosystem, British Columbia, CanadaChu, Jackson Wing Four 25 April 2016 (has links)
Natural cycles of environmental variability and long-term deoxygenation in the ocean impose oxygen deficiency (hypoxia) on marine communities. My research exploits a naturally occurring hypoxia cycle in Saanich Inlet, British Columbia, Canada where I combined spatial surveys with remotely operated vehicles, ecological time-series from the subsea cabled observatory VENUS, and lab-based respirometry experiments to examine the influence of seasonally variable oxygen conditions on epibenthic communities.
In situ oxygen thresholds established for dozens of fish and invertebrate species in this system show they naturally occur in lower oxygen levels than what general lethal and sublethal thresholds would predict. Expansion of hypoxic waters induced a loss of community structure which was previously characterized by disjunct distributions among species. Communities in variable hypoxia also have scale-dependent structure across a range of time scales but are primarily synchronized to a seasonal oscillation between two phases. Time-series revealed timing of diurnal movement in the slender sole Lyopsetta exilis and reproductive behavior of squat lobster Munida quadrispina in the hypoxia cycle. Hypoxia-induced mortality of sessile species slowed the rate of community recovery after deoxygenation. The 10-year oxygen time-series from VENUS, revealed a significant increase in the annual low-oxygen period in Saanich Inlet and that deoxygenation has occurred in this system since 2006. Differences in the critical oxygen thresholds (O2crit) and standard metabolic rates of key species (spot prawn Pandalus platyceros, slender sole, and squat lobster) determined the lowest in situ oxygen at which populations occurred and explained disproportionate shifts in distributions and community respiration. Finally, a meta-analysis on global O2crit reported for crustaceans showed that hypoxia tolerance differs among major ocean basins.
Long-term trends of deoxygenation suggest a future regime shift may occur when the duration at which a system remains below critical oxygen levels exceeds the time needed for communities to recover. Species-specific traits will determine the critical threshold and the nature of the community response in systems influenced by variable states of oxygen deficiency. However, oceanographic and evolutionary history provides context when determining the regional response of benthic communities influenced by rapidly changing environments. / Graduate / 0329 / 0416 / 0433 / jwfchu@gmail.com
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Development of Sensors and Microcontrollers for Underwater RobotsJebelli, Ali January 2014 (has links)
Nowadays, small autonomous underwater robots are strongly preferred for remote exploration of unknown and unstructured environments. Such robots allow the exploration and monitoring of underwater environments where a long term underwater presence is required to cover a large area. Furthermore, reducing the robot size, embedding electrical board inside and reducing cost are some of the challenges designers of autonomous underwater robots are facing. As a key device for reliable operation-decision process of autonomous underwater robots, a relatively fast and cost effective controller based on Fuzzy logic and proportional-integral-derivative method is proposed in this thesis. It efficiently models nonlinear system behaviors largely present in robot operation and for which mathematical models are difficult to obtain. To evaluate its response, the fault finding test approach was applied and the response of each task of the robot depicted under different operating conditions. The robot performance while combining all control programs and including sensors was also investigated while the number of program codes and inputs were increased.
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