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.

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

No description available.

Το μεγαλύτερο μέρος της επιφάνεια του πλανήτη καλύπτεται από τους ωκεανούς. Η περιέργεια του ανθρώπου να εξερευνήσει και να καταλάβει το πώς λειτουργεί το περιβάλλον του, σε συνδυασμό με την αναζήτηση νέων πόρων, ώθησε τον άνθρωπο στον υδάτινο κόσμο. Δεδομένου του βάθους της θάλασσας, οι αρχικές αυτόνομες καταδύσεις, αλλά και οι καταδύσεις με την βοήθεια αναπνευστικών συσκευών δεν κάλυψαν παρά στο ελάχιστο την πρόσβαση στον κόσμο αυτό. Η ανάπτυξη κάποιου διαμεσολαβητή ήταν όχι μόνο χρήσιμη αλλά και απαραίτητη για να προσεγγίσουμε μεγάλα βάθη αλλά και επικίνδυνα, για τους δύτες, μέρη. Στην παρούσα εργασία παρουσιάζεται η χρησιμότητα των υποβρύχιων οχημάτων, σε διάφορους τομείς των ανθρώπινων δραστηριοτήτων. Αναπτύσσονται φυσικές έννοιες και βασικοί ορισμοί για την περιγραφή του περιβάλλοντος στο οποίο λειτουργούν τα υποβρύχια οχήματα. Στη συνέχεια γίνεται αναφορά των διαφόρων κατηγοριών των υποβρύχιων οχημάτων που έχουν αναπτυχθεί μέχρι σήμερα. Αναλύονται λεπτομερώς οι τεχνολογικές τους δυσκολίες, τα πλεονεκτήματα και τα μειονεκτήματα του κάθε είδους υποβρύχιου οχήματος, καθώς επίσης και οι τεχνολογικές εξελίξεις στον τομέα αυτό. Για παράδειγμα, οι ακουστικές επικοινωνίες, η υποβρύχια πλοήγηση και η αποφυγή εμποδίων, ώστε να καταστεί εφικτή η υποβρύχια εξερεύνηση. Τέλος, παρουσιάζονται τα σπουδαιότερα υποβρύχια οχήματα που έχουν κατασκευαστεί μέχρι σήμερα και έχουν οδηγήσει σε σημαντικές ανακαλύψεις στον υδάτινο κόσμο. / -

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.

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.

The work presented in the thesis concerns the design and development of a novel thruster fault diagnosis and accommodation system (PDAS) for overactuated, open-frame underwater vehicles. The remotely operated vehicles (ROVs) considered in this thesis have four thrusters for motion in the horizontal plane with three controllable degrees of freedom (DoF). Due to the redundancy resulting from this configuration, for the case of a partial fault or a total fault in a single thruster it is possible to reallocate control among operable thrusters in order that the ROV pilot is able to maintain control of the faulty ROV and to continue with missions. The proposed PDAS consists of two subsystems: a fault diagnosis subsystem (FDS) and a fault accommodation subsystem (FAS). The FDS uses fault detector units to monitor thruster states. Robust and reliable interrogation of thruster states, and subsequent identification of faults, is accomplished using methods based on the integration of selforganising maps and fuzzy logic clustering. The FAS uses information provided by the FDS to perform an appropriate redistribution of thruster demands in order to accommodate faults. The FAS uses a hybrid approach for control allocation, which integrates the pseudoinverse method and the fixed-point iterations method. A control energy cost function is used as the optimisation criteria. In fault-free and faulty cases the FAS finds the optimal solution, which minimises this criteria. The concept of feasible region is developed in order to visualise thruster velocity saturation bounds. The PDAS provides a dynamic update of saturation bounds using a complex three-dimensional visualisation of the feasible region (attainable command set), such that the ROV pilot is informed with the effects of thruster fault accommodation, incorporated in the new shape of the attainable command set. In this way the ROV pilot can easy adapt to newly created changes and continue the mission in the presence of a fault. The prototype of the PDAS was developed in the MATLAB environment as a Simulink model, which includes a nonlinear model of an ROV with 6 DOF, propulsion system and a hand control unit. The hand control unit was simulated in hardware using a joystick as input device to generate command signals. Different fault conditions are simulated in order to investigate the performance of the PDAS. A virtual underwater world was developed, which enabled tuning, testing and evaluation of the PDAS using simulations of two underwater vehicles (FALCON, Seaeye Marine Ltd. and URIS, University of Girona) in a 'realistic' underwater environment. The performance of the PDAS was demonstrated and evaluated via tank trials of the FALCON ROV in QinetiQ Ocean Basin Tank at Haslar, where the existing control software was enhanced with the PDAS algorithm. The results of real-world experiments confirmed the effectiveness of the PDAS in maintaining vehicle manoeuvrability and in preserving the vehicle mission in the presence of thruster faults.

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.

Předkládaná práce se zabývá návrhem a konstrukcí dálkově řízené sondy pro průzkum zatopených krasových oblastí. Cílem práce je zhotovení cenově přijatelné sondy pro speleologický výzkum. Soustava senzorů a dálkově řízený kamerový systém umožňuje pořízení záběrů z velkých hloubek, které lze později analyzovat.