https://www.um.edu.mt/library/oar/handle/123456789/930 2026-09-24T18:49:18Z 2026-09-24T18:49:18Z Galea Naudi Borg, Karl Mollicone, Pierluigi Rochman, Arif Buhagiar, Joseph P. Schembri-Wismayer, Pierre https://www.um.edu.mt/library/oar/handle/123456789/149305 2026-09-23T06:15:35Z 2026-01-01T00:00:00Z

Title: Hyperelastic modelling of candidate elastomers for an inflatable knee implant Authors: Galea Naudi Borg, Karl; Mollicone, Pierluigi; Rochman, Arif; Buhagiar, Joseph P.; Schembri-Wismayer, Pierre Abstract: As the prevalence of knee osteoarthritis continues to rise, there is an urgent clinical need for load-bearing implants that can be arthroscopically delivered to restore joint function and delay major surgical intervention. This study addresses the core scientific challenges of material selection and mechanical characterisation for such implants, focusing on two candidate bioelastomers: polycarbonate urethane (PCU) (ChronoFlex C™ 80A) and silicone-polycarbonate copolymer (Si-PC) (ChronoSil® 93A). The novelty of this work lies in combining experimental hyperelastic material model generation for these candidate implant elastomers with a multiphysics computational assessment of a novel arthroscopically insertable inflatable knee implant for loadbearing osteoarthritis treatment. Comprehensive mechanical testing, including uniaxial tension, compression, planar shear and volumetric compression, was performed to quantify the nonlinear elastic behaviour of the two materials. Multiple hyperelastic material models, namely neo-Hookean, Mooney–Rivlin, Ogden, Ogden third order and polynomial third order, were fitted to the experimental data, and their accuracy was assessed through numerical modelling. For PCU, the neo-Hookean and Mooney–Rivlin models exhibited the lowest mean absolute errors, while the Ogden model showed improved performance in the working strain range (−50% to 100%). For Si-PC, only the neo-Hookean model fell below 10% error. These validated material models were then incorporated into a multiphysics computational framework to simulate the mechanical behaviour of a novel inflatable knee implant under physiological load, demonstrating acceptable structural response and favourable stress profiles. The computational model included knee joint structures derived from magnetic resonance imaging and computed tomography scans, hyperelastic material models, time-dependent loading and fluid–structure interactions between the implant and fluid contained within it. The integration of rigorous experimental characterisation and advanced material modelling provides a robust foundation for the future computational optimisation and clinical implementation of soft knee implants.

2026-01-01T00:00:00Z Bachmann, C. Aiello, G. Ambrosino, R. Balazs Bajari, J. Boscary, J. Carusotti, S. Claps, V. Cufar, A. Elbez-Uzan, J. Federici, G. Franke, T. Giannini, L. Gliss, C. Härtl, T. Hopf, C. Luongo, C. Maione, I. Maisonnier, D. Marzullo, D. Maviglia, F. Marek, P. Mollicone, Pierluigi Moscato, I. Mozzillo, R. Muscat, Martin Pagani, I. Park, J. H. Pereslavtsev, P. Quartararo, A. Renard, S. Steinbacher, T. Tarallo, A. Vallone, E. Vigano, F. Wiesen, S. Wu, C. https://www.um.edu.mt/library/oar/handle/123456789/149304 2026-09-23T06:11:44Z 2025-10-01T00:00:00Z

Title: Progress in the concept development of the VNS — a beam-driven tokamak for component testing Authors: Bachmann, C.; Aiello, G.; Ambrosino, R.; Balazs Bajari, J.; Boscary, J.; Carusotti, S.; Claps, V.; Cufar, A.; Elbez-Uzan, J.; Federici, G.; Franke, T.; Giannini, L.; Gliss, C.; Härtl, T.; Hopf, C.; Luongo, C.; Maione, I.; Maisonnier, D.; Marzullo, D.; Maviglia, F.; Marek, P.; Mollicone, Pierluigi; Moscato, I.; Mozzillo, R.; Muscat, Martin; Pagani, I.; Park, J. H.; Pereslavtsev, P.; Quartararo, A.; Renard, S.; Steinbacher, T.; Tarallo, A.; Vallone, E.; Vigano, F.; Wiesen, S.; Wu, C. Abstract: The volumetric neutron source (VNS) is a compact beam-driven tokamak with D-T plasma to generate a high neutron flux that will allow the testing and qualification of fusion nuclear components, in particular the breeding blanket. Recently, EUROfusion concluded a feasibility study that confirmed the feasibility of VNS for construction and operation. Also, aspects were identified that require further development and assessment, and these have been key subjects of the on-going conceptual design phase. This article summarizes the progress made in the design of VNS, including (i) the rationale for the minor modifications of major radius and aspect ratio, (ii) the configuration and performance of the equilibrium coils, (iii) the design of the in-vessel components including their remote handling concepts, (vi) design of the nuclear buildings and layout of the main plant systems including those related to the fuel cycle.

2025-10-01T00:00:00Z Attard, Daniel Saliba, Michael A. Mollicone, Pierluigi Rochman, Arif Fan, Dixia https://www.um.edu.mt/library/oar/handle/123456789/149303 2026-09-23T06:09:32Z 2025-12-01T00:00:00Z

Title: Development of a preliminary prototype robotic gripper inspired by the tentacles of cuttlefish Authors: Attard, Daniel; Saliba, Michael A.; Mollicone, Pierluigi; Rochman, Arif; Fan, Dixia Abstract: Soft robotic grippers offer unique advantages when it comes to tasks involving the delicate manipulation of irregular objects with a high degree of shape variability. These advantages stem from the use of inherently compliant soft materials, making them the safer option in many applications. Taking inspiration from biological systems, controlled deformation is “programmed” into a soft gripper through its geometry and materials, as opposed to joints and linkages as in conventional pinch-type grippers. This work outlines the development of such a system, a cable-actuated soft robotic gripper whose prehension is inspired by the tentacles of a cuttlefish. A segmented geometry and tendon-like actuation define the design to replicate the effortless, distributed bending observed in nature. The system development involved material selection, structural design, actuation and transmission design, manufacturing constraints, and the control system design. Through the integration of these elements, this work demonstrates a structured approach to building a soft bioinspired robotic gripper.

2025-12-01T00:00:00Z Fenech, Andrew Saliba, Anthony Theodore Farrugia, Mario https://www.um.edu.mt/library/oar/handle/123456789/145777 2026-04-21T08:49:28Z 2026-03-01T00:00:00Z

Title: Dual fuel knock mitigation technique through liquid state injection Authors: Fenech, Andrew; Saliba, Anthony Theodore; Farrugia, Mario Abstract: Dual-fuel engines allow the use of alternative fuels such as Liquified Natural Gas (LNG). Using LNG as the main energy source and a smaller quantity of diesel (to initiate combustion) offers the benefit of decreased emissions. The reduction of emissions is mostly due to the gaseous fuel’s better ability to burn more effectively. The gaseous fuels (e.g. methane CH4) has a lower carbon to hydrogen ratio than diesel and therefore less CO2 is produced. Particulate matter typically generated with diesel combustion is also greatly reduced. The use of dual fuel is however impacted by an operational phenomenon referred to as engine knock which limits the operational window of the engine. This knocking problem is accentuated during transients. The objective of this paper is to explore liquid state injection of LNG/propane. A small quantity of pressurized LNG/propane is injected into the airstream to lower the temperature of the charge air through the latent heat of evaporation of the LNG/propane. This liquid state injection is intended to lower the knock propensity especially during load increase transients where fuel is increased before the mass air flow has picked up (due to turbo lag).

2026-03-01T00:00:00Z