https://www.um.edu.mt/library/oar/handle/123456789/83113 Thu, 09 Apr 2026 09:29:34 GMT 2026-04-09T09:29:34Z https://www.um.edu.mt/library/oar/handle/123456789/92489 Title: Design of a child resistant cosmetic closure mechanism Abstract: This project was conducted in order to design a child-resistant cosmetic closure mechanism for Toly Ltd., the industrial partner. The academic objectives consisted of critical reviews of standards and patents, generating alternative working principles of the child-resistant package as well as conducting an FMEA and DFMA exercise of the selected final solution. On the other hand, the industrial objectives consisted of identifying the design specifications, generating alternative solution concepts and selecting the best solution based on several criteria. Moreover, prototyping development and testing of the selected solution, as well as a detailed design for mass production for the selected solution, were also required. The basic design cycle was used to have a logical structure within this project. This allowed the implementation of various tools and methods in the early stages of design, such as the PDS, QFD, and SCAMPER. Later stages utilised other approaches such as 3D modelling and rapid prototyping. Various alternative concepts were produced, analysed and evaluated through brainstorming, creative thinking, numerous analyses as well as a decision matrix. The selection process comprised elements such as manufacturability, assembly, and child resistance. Furthermore, a number of physical prototypes were developed using cutting-edge equipment at the engineering faculty, which were produced from CAD models. When the physical prototype was completed, the design was examined and tweaked to meet both the academic and industrial objectives while facilitating injection moulding and mass production while lowering the risk of failure during manufacture. Finally, the changes were implemented to the 3D CAD models. Description: B.Eng. (Hons)(Melit.) Fri, 01 Jan 2021 00:00:00 GMT https://www.um.edu.mt/library/oar/handle/123456789/92489 2021-01-01T00:00:00Z https://www.um.edu.mt/library/oar/handle/123456789/92478 Title: Interlayer adhesion optimisation of fused deposition modelling 3D printed PEEK Abstract: Fused deposition modelling (FDM) has become the preferred 3D printing method for hightemperature polymeric materials. This is mainly due to FDM’s wide availability and comparatively minimal cost of entry. Poly-ether-ether-ketone (PEEK) is one such high-temperature, highperformance polymer with several potential uses in various industries and applications. However, its use hinges upon whether the required geometry may be successfully 3D printed in such a way that its high-performance characteristics and properties are retained in the produced part. This project, developed in collaboration with the University of Malta and Trelleborg Sealing Solutions Malta, aims to develop an optimised printing profile which results in strong interlayer adhesion of successive layers of the printed geometry, as printed in the Z-axis, vertical build orientation. Towards this aim, this project considered the effects of four quantitative printing parameters, namely: Layer Height, Nozzle Temperature, Printing Speed, and Extrusion Multiplication over two levels (or parameter values), on the tensile strengths and flexure strengths of a set of standard testing geometry. The selection of these four factors and their levels was based on a review of the available literature, and on observations made by the researcher during a series of familiarisation experiments with the printer being utilised. A Design of Experiment (DoE) technique, the associated theory, and several statistical tools were utilised in the design, analysis, and interpretation of the results obtained. The best performing tensile test specimen was specimen 16, with optimised parameter values of LH = 0.2mm, NT = 430˚C, Speed = 1800mm/min, and EM = 0.8. This specimen had an observed ultimate tensile strength of around 19MPa. This value was considerably below the 100MPa tensile strength observed in moulded PEEK specimens. The best performing flexural test specimen meanwhile was specimen 6, with optimised parameter values of LH = 0.1mm, NT = 430˚C, Speed = 900mm/min, and EM = 0.8. This specimen had an observed flexural strength of 116.4MPa, which was comparable to the flexural strength observed in moulded PEEK specimen which had a value of 164MPa. Description: B.Eng. (Hons)(Melit.) Fri, 01 Jan 2021 00:00:00 GMT https://www.um.edu.mt/library/oar/handle/123456789/92478 2021-01-01T00:00:00Z https://www.um.edu.mt/library/oar/handle/123456789/92418 Title: Design of 3D printed customisable post-stroke rehabilitation devices to provide a high-quality user experience Abstract: Cerebrovascular Accidents, also referred to as strokes, are one of the leading causes for disabilities in the world. Hence rehabilitation devices have been introduced to post-stroke rehabilitation programs to facilitate the therapists’ work and assist the patient. The popularity of 3D printing in the healthcare industry has also increased due to its high customisability benefits. Therefore, the primary objective of this project was to analyse the design of 3D printed customisable rehabilitation device which provides a high-quality User Experience (UX) for post-stroke patients. This was carried out by selecting an off-the-shelf device as a case-study and follow the design cycle to improve it through AM. A literature review of previous studies regarding rehabilitation devices with a user-centred approach was carried out. A comprehensive review and comparison was also conducted to grasp a critical understanding of the strengths and limitations each of the selected state-of-the-art rehabilitation devices and their User Experience. By following the design cycle, the Problem Analysis was carried out by gathering data from observations of a demonstration by physiotherapists and a study conducted with occupational therapists. This allowed for a better understanding of the user and functional requirements as well as assisted in the prioritizing of the technical parameters necessary for the creation of the Product Design Specification. The Solution Synthesis presents an iterative process used to develop concept solutions of rehabilitation devices. The most suitable concept was selected as the provisional design for the following design stage. This design was modified and improved by designing it for AM and User Experience. The developed design was simulated, and 3D printed to realise the product’s characteristics in the form of a functional prototypes. In the Evaluation phase the 3D printed device was also evaluated with typical stakeholders to assess the User Experience. The results prove that 3D printing is an improved means of manufacturing to obtain a customised post-stroke rehabilitation device with high-quality User Experience when compared to off-the-shelf products. There is still a lot of research required to continue exploiting the benefits of AM in rehabilitation devices such as through multi-material 3D printing. Description: B.Eng. (Hons)(Melit.) Fri, 01 Jan 2021 00:00:00 GMT https://www.um.edu.mt/library/oar/handle/123456789/92418 2021-01-01T00:00:00Z https://www.um.edu.mt/library/oar/handle/123456789/92363 Title: The use of recycled PET for high performance injection moulded components Abstract: Recycling plays a crucial part in a circular economy. However, due to contamination and material degradation during a material’s use phase, the material properties of recycled material is reduced significantly, many times being used for second class applications. Instead, this project aims to upscale the properties of recycled PET (rPET) such that to achieve high performance mechanical properties with an injection moulding process. Hence, the aim of this project is to increase the tensile properties and thermal properties of rPET, in order to reach high performance properties, such as PEEK. Studies have shown that with the use reinforcing fibres, such as, E-glass or Basalt fibres, the tensile properties increases significantly. Ceramic fillers, coupling agents and nucleating agents may also increase the tensile properties, as the two former enhance the adhesion and bonding between the two phases of the composite, while the latter increases the crystallinity of the material. To increase the melting temperature, the chemical composition of the polymer would need to be amended; however, composites with added glass fibres demonstrate significant greater strength at elevated temperatures. Calculations show that Basalt and S-glass fibres are an attractive sustainable alternative to the more commonly used E-glass fibres, as other than displaying greater strength, they display better environmental properties. Tensile specimens, designed according to the ISO527 standard, were produced with rPET and additional E-glass and S-glass reinforcing fibres. Fibres were cut and added manually into the hopper, which proved to be significantly hard due to clogging and clumping of the fibres. In fact, for samples made of E-glass fibres, only a fibre content of less than 1% was obtained. At such a low fibre content, no increase in tensile properties was observed. However, the maximum fibre content obtained for S-glass fibres was nearly 12%. Although at 12% the strength only increased by 6.4%, the Young’s Modulus increased by 65% reaching a maximum value of 4.41GPa, exceeding that of PEEK. This increase is significantly lower than the predicted calculations where, at 12% fibre content, the Young’s Modulus should have increased by 109%. Only a 65% increase was obtained primarily due to the inhomogeneous mixture observed from micrograms as well as significant material degradation from the injection moulding process. This was due to difficulty when trying to input the glass fibres as well as the disuse of an extrusion or compounding process. Description: B.Eng. (Hons)(Melit.) Fri, 01 Jan 2021 00:00:00 GMT https://www.um.edu.mt/library/oar/handle/123456789/92363 2021-01-01T00:00:00Z