257 research outputs found
Letter fro Martin F. Toal to Hagan
No full textHolograph letter from Martin F. Toal, Collegio Brignole Sale, Via Fassolo 29, Genoa, to Hagan, concerning the bed Daniel O'Connell died in. Monsignor O'Riordan had made efforts to obtain it; the owners are now in a position to give it to the Irish people. Asking whether the Irish College would receive it; the last descendant Sir John O'Connell is entering a monastery and it ought not to end up in a museum or rot in a magazine. Season's greetings
Letter from Martin F. Toal to Hagan
No full textHolograph letter from Martin F. Toal, Collegio Brignole Sale, Via Fassolo 29, Genoa, to Hagan. Explaining that the matter of Daniel O'Connell's deathbed cannot be finalised for a while yet; explaining circumstances. The owner of the villa it is in is a Signore Bolgarelli, he is very old and the only one who can identify the bed. Reiterating more fully that the item 'would be out of place in modern Ireland where the blighting shadow of Leinster House would rest on it were it honoured by a place in that museum. Ireland at present seems to have no place in its affections for those who illumined its past'. [Enclosing] holograph card from Rector G. Latini C.M. of Brignole-Sale, Genoa, to (Hagan), repeating that it would be premature to send a student for the bed
A Simulation Tool for Home Energy Production and Storage System Using Photovoltaic and Airborne Wind Energy
No full textThis paper presents a software tool called EPSS-AWE (Energy Production and Storage Simulator - Airborne Wind Energy) that simulates a hybrid solar-wind energy production and storage home system, in which the wind power production element is an AWE generation system and the solar element is a traditional photovoltaic (PV) plant. Simulation based on realistic data can be used to evaluate the performance of hybrid power production and storage systems in different configurations, and to correctly size their components in the design phase
A hybrid control architecture development for the guidance, navigation and control of the tethra prototype submersible vehicle
No full textThe Mobile & Marine Robotics Research Centre (MMRRC) at the University of Limerick is developing a highly manoeuvrable AUV platform to address the challenges of highresolution seabed survey in both shallow and deep water. The work of the author in the development of a novel guidance, navigation and control (GNC) system for the Tethra AUV is described in the thesis. A full and comprehensive GNC system, with open architecture, has been designed, implemented and tested with many novel features.
The main components of the control system include: Control Allocation, Virtual Joystick, Low-level controllers, Fuzzy controller for Obstacle Avoidance and Behaviour Coordinator/Arbitration.
As result of the research and development of the author the Tethra AUV has been endowed with a comprehensively integrated Guidance Navigation and Control system, enabling the execution of full survey scale operations in challenging near seabed scenarios
A high frequency wide field of view ultrasonic sensor for short range collision avoidance applications on intervention class underwater vehicles
No full textIn this thesis a novel sensor design for intervention class AUVs and UUVs is described. The objective of this study is the development of sensor solutions that facilitate autonomous or remote guidance of underwater vehicles in close proximity to marine platforms, the seafloor or other hazards. In particular, this study addresses the need for improved sensing within the working envelope of intervention class vehicles. A literature review of the state-of-the-art in collision avoidance sensors identifies a number of performance and design shortfalls with currently available sensors as applied to intervention class UUVs and AUVs generally. This thesis then focuses on addressing these sensing shortfalls and in so doing strives to remove a practical impediment to the realisation of viable intervention AUVs. The sensor developed tested and evaluated provides a low-cost solution based on ultrasonic sensing principles. The new sensor design is characterised by a wide-angle spatial transmission pattern, good range resolution, short minimum detection range and fast response time. In target applications such as station keeping, docking and close quarters collision avoidance where reliable sensor coverage in the working envelope of a vehicle is of critical importance to vehicle safety, multiple ‘short range’ sensors with overlapping detection patterns can be used to augment data obtained using conventional ‘long range’ sonar and vision sensors
Performance optimised reverberation modelling for real-time synthesis of sidescan sonar imagery
No full textIn this thesis a novel performance optimised approach to sidescan sonar simulation is described. Seminal approaches to sonar simulation reported in the literature are seen to produce visually realistic results that are verified using statistical and spectral methods. The problem is that the computational implementations of the underlying acoustic models are numerically intensive to an extent that prohibits real-time implementation. It is shown in this thesis that for sonar imaging simulations, the principal performance-limiting factor is the method of processing applied to the highly intricate and excessively detailed polygonal mesh required to accurately model seafloor reverberation. By current techniques, discovery of ensonifed facets at each ping requires direct interrogation of each facet constructing the seafloor mesh to determine its contribution to the backscattered imagery. The inherent computational bottleneck significantly arrests the runtime performance delivered by the simulation. From a literature review it emerged that the performance-related challenges to be overcome in sonar simulation have direct parallels with those encountered in the field of 3D graphics rendering when processing object models for interactive visualisation. Several schemes presented in the computer graphics literature to address this issue are identified in this thesis as suitable candidates to accelerate sonar simulation. A novel sidescan sonar simulator is then implemented by incorporating a mesh abstraction pipeline within the simulation process to dynamically adapt the local seafloor geometry according to its spatial proximity to the roving sonar fanbeam footprint. In the resulting transitional multi-resolution mesh, the ensonifed swathe is described at its full original resolution and geometry, while non-ensonifed regions are described by orders of magnitude fewer geometric primitives. The new approach to sonar simulation is experimentally tested and the results show it to offer a performance acceleration translating to an orders of magnitude improvement in simulation response times. Most important, it is also shown that the increased simulation throughput effectively translates current sonar simulation technology from offline to online application while affecting no degradation to the integrity of simulator-generated imagery
An energy efficient pneumatic-electricity system – modelling study of the scroll expender
No full textMASK - increasing sea knowledge awareness among high school students using marine robots
No full textCOVID-19 pandemic impacted considerably the field of school education. In-presence learning was largely replace for blended learning or fully remote learning for extended periods of time. This has led in certain cases to increase the digital divide. Moreover, hands-on projects were limited by the same reasons. On the other hand, many universities fully exploited their capabilities and further developed the field of remote access to infrastructures allowing partners that could not travel to
utilise the robots and installations from their homes. This is particularly helpful in the field of marine robotics where tests at sea are expensive and logistically complex. Finally, the e-learning and remote testing possibilities opened up an opportunity for smaller environmental footprint of teaching and testing activities. Exploiting these opportunities, a consortium of three universities and two high schools started the Marine Robots for better Sea Knowledge awareness (MASK) project. This paper presents the project and its initial results and provides qualitative assessment of the current results
Distributed control system and novel power take off method for pumping-mode airborne wind energy
No full textThe robotic control of tethered parafoils enables a number of exciting applications,
primarily a novel approach to wind energy generation. The airborne wind energy
(AWE) paradigm aims to reduce greatly the mass and cost of materials required to
generate electrical power from the wind. With innovative, distributed control systems
and advanced materials, free flying tethered wings can replace the tower and blades of a
conventional wind turbine, with the power take off system relocated to ground level.
The critical enabling challenge faced by such systems, is the development of suitable
control system hardware and software architectures with robust controllers maintaining
the safe and optimal operation of the system. Suitable power take off methods form an
integral part of AWE systems, as the mechanical power is produced on a periodic cycle.
A holistic approach to the design, development and testing of a distributed control
system for the flight of tethered kites has been undertaken. The airborne control
element must operate harmoniously with the ground based power take off unit. A series
of flight tests of a prototype control system developed has been carried out in the field.
A detailed analysis of results and outcomes is provided. Paralleling the prototype
development a mathematical model and simulation tool for the power take off
synchronisation of multiple AWE systems has been developed with analysis of the
performance and requirements for such a system. Continuous power output is achieved
from multiple interconnected cyclical sources in a model that presents one feasible
AWE farm topology. Having gained low cost access to altitude, additional payload
applications for the automatic flight of parafoils emerge such as aerial sensor and
observation platforms or ‘over the horizon’ communications links
Using DotNetNuke in development and implementation of marine robotics research at University of Limerick
No full textThis thesis explores using the open source content management system DotNetNuke (DNN) for the design and implementation of a portal website for the Mobile & Marine Robotic Research Centre (MMRRC) at University of Limerick. This was done in collaboration with the research team in university research centre. Based on plenty of research material accumulated during years of studies, the MMRRC website would be a platform for visitors or interested researchers to learn about the research activities and projects undertaken by MMRRC team at University of Limerick and keep the latest news updated on the website all the time. During this project, there was an exercise in Shannon Estuary which explored a ship undersea and simulate oil leak from the ship. The MMRRC team played significant role in planning and executing the exercise. Video, pictures, as well as real-time data obtained from this exercise were updated on the website. In contrast to traditional websites, this portal website developed with DNN can be easily and conveniently managed by administrators using role-based approach
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