https://www.um.edu.mt/library/oar/handle/123456789/930 2026-10-29T11:06:05Z 2026-10-29T11:06:05Z Jing, Fengmei Guo, Jiahao Wang, Xinru Mei, Yunlei Zhang, Dingming Ye, Weixiang Le, Conghuan Fan, Yali Zhu, Yanqi Micallef, Christopher Sant, Tonio Mollicone, Jean-Paul https://www.um.edu.mt/library/oar/handle/123456789/150319 2026-10-22T06:14:45Z 2026-01-01T00:00:00Z

Title: Towing response and drag reduction in a semi-submersible floating offshore wind turbine platform with fairings Authors: Jing, Fengmei; Guo, Jiahao; Wang, Xinru; Mei, Yunlei; Zhang, Dingming; Ye, Weixiang; Le, Conghuan; Fan, Yali; Zhu, Yanqi; Micallef, Christopher; Sant, Tonio; Mollicone, Jean-Paul Abstract: To reduce the wet-towing resistance of a semi-submersible floating offshore wind turbine (FOWT) platform, this study proposes the installation of fairings on the outer columns and investigates their influence on the platform motion response during towing through numerical simulation. The drag reduction performance of a single fairing on a cylindrical column is experimentally validated through scaled towing tank tests. Four fairing arrangement schemes are then designed, from which two schemes that satisfy intact stability requirements are selected. A platform-level CFD analysis is further conducted to quantify the drag reduction in the full platform, showing that Scheme 1 (all forward) and Scheme 2 (two forward, one aft) achieve drag reductions of 5.09% and 5.95%, respectively. A numerical representation of the complete towing system, comprising the platform, tugboat, and cables, is developed within the AQWA environment. The hydrodynamic model of the unmodified platform is numerically validated against free-decay data. The study proceeds with a frequency-domain assessment of the platform’s hydrodynamic behavior, followed by time-domain simulations to evaluate its motion responses under regular wave excitation. The results show that the triangular fairing provides stable drag reduction under different towing speeds and draft conditions. The fairings predominantly alter the added mass, radiation damping, and RAO in the pitch direction, while their influence on the heave and roll motions is relatively limited. For Scheme 1, the peak pitch added mass increases by 36.7%, the peak pitch radiation damping increases by 223.8%, and the peak pitch RAO increases by 20.3% relative to the bare platform. Scheme 2 induces smaller overall perturbations to the motion response compared with Scheme 1, while also offering a slightly higher drag reduction at the platform level. The study reveals that while fairings effectively reduce towing resistance, they also significantly modify the pitch motion characteristics of the platform. In engineering applications, both drag reduction benefits and motion performance changes should be comprehensively considered, and the fairing arrangement should be selected accordingly.

2026-01-01T00:00:00Z Abela, Luca Saliba, Michael A. https://www.um.edu.mt/library/oar/handle/123456789/149442 2026-09-28T08:06:28Z 2025-01-01T00:00:00Z

Title: Preliminary design and characterisation of a force and position sensor for a prosthetic finger Authors: Abela, Luca; Saliba, Michael A. Abstract: Modern prosthetic hands often lack force-sensing capabilities or the ability to detect the precise location of applied forces, limiting user feedback and dexterity. This work presents the analysis and preliminary development of a compact and practical force sensor for potential integration into a prosthetic finger. The design incorporates four strain gauges mounted on an internal beam structure to measure both force magnitude and point of application. A prototype was fabricated, and its performance was evaluated across varying force and location ranges. Results showed a mean absolute force error of 4.24% and a mean absolute position error of 2.7 mm. The proposed sensor contributes to advancing tactile sensing in prosthetics, and supports the development of more functional, user appropriate prosthetic hands which can enhance the quality of life for amputees.

2025-01-01T00:00:00Z Caruana, Martina Saliba, Michael A. Brincat, Norbert https://www.um.edu.mt/library/oar/handle/123456789/149438 2026-09-28T08:00:13Z 2025-01-01T00:00:00Z

Title: Robotics outreach : laboratory demonstrations for diverse audiences Authors: Caruana, Martina; Saliba, Michael A.; Brincat, Norbert Abstract: Robotics has seen a surge in popularity as an educational and engagement tool, leading the Robotic Systems Laboratory at the University of Malta to embark on the development of comprehensive outreach activity. This paper outlines the development of a coherent demonstration strategy and of targeted robotic demonstrations aimed at diverse audiences, including primary and secondary school students, tertiary education students, the general public, and visiting researchers. A structured design approach, incorporating quality function deployment, function-means analysis, and decision matrices, guided the conceptualisation and development phases. Five distinct demonstrations were developed: shapes drawing for primary students, pick-and place block handling for secondary students, a stair-descending robot demonstration for tertiary students, a cocktail-making demonstration for the general public, and a bottle-cap presence checking demonstration for visiting researchers. Post demonstration surveys gathered feedback, informing valuable suggestions for improvement, such as increasing robot operating speed for younger audiences and expanding complexity for advanced learners. The work concludes that these demonstrations can significantly enhance the outreach, educational, and engagement values of the laboratory, potentially increasing revenue and reach, and supporting the mission of the laboratory as a centre for public outreach and technological advancement.

2025-01-01T00:00:00Z Vella, Michela Saliba, Michael A. https://www.um.edu.mt/library/oar/handle/123456789/149437 2026-09-28T07:56:43Z 2025-01-01T00:00:00Z

Title: Biomechanical analysis and preliminary transtibial prosthesis design for pedal harpists Authors: Vella, Michela; Saliba, Michael A. Abstract: The concert harp is a string instrument played using both the hands and the feet. Harpists pluck the strings with their fingers while operating seven foot-pedals that change the pitch of the string notes. For this reason, the instrument is inaccessible to individuals with lower limb amputations. This work investigates the biomechanics of harp playing and proposes a new dedicated transtibial prosthesis design. A custom pedal jig was built, replicating the pedal box of the harp, and used in motion and force capture trials conducted using a Vicon system and Plug-in-Gait model. Analysis revealed rapid pedal transitions and foot motion that are distinct from and more demanding than everyday activities such as walking or running, and that cannot be performed by current commercial prostheses. A preliminary design has been developed based on these analyses, and evaluated using CAD simulations in Autodesk Inventor, confirming that the required range of motion can be achieved. Actuator selection was based on calculated forces derived from the biomechanical data. The preliminary design meets the key functional requirements.

2025-01-01T00:00:00Z