When carrying out sampling tasks close to the ocean bottom, a ROV keeps station at a fixed position and compensates the tether effects and currents. However, the operation of ROV thrust propellers for station keeping might stir up sediment and cause poor visibility, which forces ROV operators to stop work until the sediment clears. The purpose of this thesis, therefore, is to design and fabricate a seafloor moving platform able to approach steadily to sampling objects without stirring up much sediment. This moving platform must be combined with the second generation NCKU-NSYSU ROV, a sampling manipulator, and a sample storage apparatus. Also, the moving platform requires some capabilities for travel over relatively smooth seafloor. A wheel-driven mobile platform, as a result, is developed, in which the front wheels and rear wheels are respectively driven by two separately provided DC motors. The required power and serial command signals are transmitted to the platform via the second generation NCKU-NSYSU ROV. A four-bar linkage for steering font wheels is designed to work close to the Ackerman condition, and a chain-and-sprocket drive train is used to transfer power to the rear wheels. The motor controllers used for controlling DC motors are constructed based on MSP430 MCU (Micro Controller Unit). The preliminary driving performance of the platform is tested. The testing results indicate that the moving platform can drive steadily and behave as expected.

The acquisition of marine survey data is traditionally undertaken from surface vessels including boats and temporary rigs. Translation of these techniques to the nearshore zone is a complex task and requires equipment adaptation and. often the sacrifice of data coverage. The remotely operated vehicle (ROV) offers the potential for overcoming some of the standard nearshore survey Concems, providing remote intervention and data acquisition in areas of restricted access. In situ testing is the most efficient and reliable method of acquiring data with minimal sediment disturbance effects. Research has been undertaken into the viability of nearshore cone penetration testing (CPT) which has shown the T-Bar flow round penetrometer to be a possible solution. Data could be acquired in sediments with undrained shear strengths of up to 300 kPa from a bottom crawling ROV weighing 260 kgf and measuring 1 m in length by 0.6 m in width. The collection of sediment cores may be necessary in areas requiring ground truthing for geophysical or in situ investigations. A pneumatic piston corer has been designed and manufactured and is capable of collecting sediment cores up to 400 mm in length, 38 mm in diameter, in sediment with undrained shear strength of 17 kPa. To ascertain additional sediment characteristics in situ, a resistivity subbottom profiling system has also been designed and tested and allows for discrimination between sediment types ranging in size from gravel to silt. The integration of equipment and testing procedures can be fiirther developed through the use of integrated data management approaches such as geographical information systems (GIS). An offthe- shelf GIS, Arclnfo 8, was used to create a GIS containing typical nearshore data using the Dart estuary as a case study location.

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ITC/USA 2014 Conference Proceedings / The Fiftieth Annual International Telemetering Conference and Technical Exhibition / October 20-23, 2014 / Town and Country Resort & Convention Center, San Diego, CA / This paper discusses the rover engagement display (RED), an application that integrates network communication, control systems, numerical and visual analysis of telemetry, and a graphical user interface for communicating with the embedded systems of a remote vehicle. The target vehicle is a wheeled rover participating in the University Rover Challenge, a competition that observes the performance of rovers in an environment similar to that of the planet Mars. Communication with the rover occurs via a TCP connection and messages adhere to a simple protocol. The RED user interface is visually modular in an attempt to provide additional scalability and extensibility. Control algorithms, user interface design concepts, and code architecture (C#) are discussed.

Resolving diversity patterns and their underlying drivers has application for both ecological theory and ocean management. Because seafloor characteristics are often used to assess bottom habitat, I examined the relationship between deep-sea benthic (bottom-living) diversity and multi-scale topographic heterogeneity. Most work occurred on the Canadian Pacific continental shelf at Learmonth Bank with additional sites in Strait of Georgia (BC) and Gulf of Maine (Atlantic shelf). High-resolution species distribution and seafloor data were annotated from remotely operated vehicle benthic imagery surveys while large-scale seafloor data were derived from multibeam sonar. New method development to address problems of current methods and to facilitate comparison among ecosystems is a major outcome. My new MiLS method (microtopographic laser scanning) can profile the deep seafloor at a resolution of ~1-2 cm with high accuracy and precision. I also developed a new ACR (arc-chord ratio) rugosity index as a measure of 3-D topographic heterogeneity that is simple, accurate and highly versatile. Model systems and scales vary among my studies but results consistently yield a positive relationship between diversity and topographic heterogeneity and identify bottom hydrodynamics as an important underlying driver. Rockfish Sebastes spp. associate with higher seafloor rugosity non-randomly and select for deep-sea corals and sponges over inert substrata alone. Data indicate that degradation of biogenic structures is a long-term detriment to rockfish species. Gorgonian coral- and sponge-dominant biotopes strongly associate with a single substratum type. These relationships were used to map coral and sponge distributions. This work, which collectively adds new information on the ecological relevance and distribution of corals and sponges, is pertinent to the conservation and management of fish stocks and vulnerable marine ecosystems. Epibenthic community variables abundance, richness, and Shannon diversity positively correlated with both the local microtopographic heterogeneity on a scale of 10 m2 and with the surrounding regional large-scale topographic heterogeneity on scales of 25 to 250,000 m2. Relationships were strongest between epibenthic community variables and the largest scale rugosity and were used to generate and test predictive diversity models. Where management strategies rely on surrogate measures in data-poor areas, mapping benthic diversity using ACR rugosity will provide good indicators. Although bottom hydrodynamics is consistently identified as an underlying driver of epibenthic patterns related to topographic heterogeneity, data suggest the nature of the relationship varies across spatial scales. At small scales, high topographic heterogeneity likely increases diversity by increasing the number of available niches (including hydrodynamic gradients; e.g., the abrupt vertical rugosity created by tall corals and sponges provides rockfish refuge from currents) while at large scales, high topographic heterogeneity increases local diversity less directly through distant hydraulic events that alter bottom flow hydrodynamics. / Graduate / 0329 / 0416 / 0799 / cdupreez@uvic.ca

This research investigates the impact a Remotely Operated Vehicle (ROV) program has on student interest in, and perception of, technology and engineering (sTEm). ROV programs embed areas of science, technology, engineering and math (STEM) into their curriculum; however, emphasis for this study is placed on interest and perception of the "T" and "E" of STEM. Although there are many articles detailing the benefits of ROV programs, there is little empirical data documenting the impact on student interest and perception of sTEm. This study outlines the background of a few major ROV programs in the U.S.; specifically Utah Underwater Robotics (UUR), an ROV statewide program within a landlocked state, the methods for gathering data and findings from a sTEm survey instrument administered to over 300 students ranging from 6th to 12th grade who participated in a five-month ROV program and near 50 students who did not. Key findings include: 1. Males were more interested in technology and engineering than females, regardless of whether they participated in the UUR ROV program. 2. Male and female students in the UUR program were more interested and had a more positive perception of engineering than those who did not participate in the UUR ROV program. 3. Females in the UUR program reported more interest in engineering careers and activities than females not in the program. 4. Females in the program reported more interest and self-efficacy in science than females not in the program. 5. Males in the UUR program reported more awareness of the positive and negative consequences of technology and engineering than those who did not participate.

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

In the past decade, the design and manufacturing of intelligent multipurpose underwater vehicles has increased significantly. In the wide range of studies conducted in this field, the flexibility and autonomy of these devices with respect to their intended performance had been widely investigated. This work is related to the design and manufacturing of a small and lightweight autonomous underwater vehicle (AUV) with vision capabilities allowing detecting and contouring obstacles. It is indeed an exciting challenge to build a small and light submarine AUV, while making tradeoffs between performance and minimum available space as well as energy consumption. In fact, due to the ever-increasing in equipment complexity and performance, designers of AUVs are facing the issues of limited size and energy consumption. By using a pair of thrusters capable to rotate 360o on their axis and implementing a mass shifter with a control loop inside the vehicle, this later can efficiently adapt its depth and direction with minimal energy consumption. A prototype was fabricated and successfully tested in real operating conditions (in both pool and ocean). It includes the design and embedding of accurate custom multi-purpose sensors for multi-task operation as well as an enhanced coordinated system between a high-speed processor and accustomed electrical/mechanical parts of the vehicle, to allow automatic controlling its movements. Furthermore, an efficient tracking system was implemented to automatically detect and bypass obstacles. Then, fuzzy-based controllers were coupled to the main AUV processor system to provide the best commands to safely get around obstacles with minimum energy consumption. The fabricated prototype was able to work for a period of three hours with object tracking options and five hours in a safe environment, at a speed of 0.6 m/s at a depth of 8 m.

Orientador: Prof. Dr. Magno Enrique Mendoza Meza / Coorientadora: Profª. Drª. Silvia Lenyra Meirelles Campos Titotto / Dissertação (mestrado) - Universidade Federal do ABC, Programa de Pós-Graduação em Engenharia Mecânica, Santo André, 2018.