OAR@½ñÈÕºÚÁÏ Collection:/library/oar/handle/123456789/831132026-08-07T05:24:35Z2026-08-07T05:24:35ZDesign of a child resistant cosmetic closure mechanism/library/oar/handle/123456789/924892022-03-29T06:14:54Z2021-01-01T00:00:00ZTitle: 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.)2021-01-01T00:00:00ZInterlayer adhesion optimisation of fused deposition modelling 3D printed PEEK/library/oar/handle/123456789/924782022-03-29T06:13:19Z2021-01-01T00:00:00ZTitle: 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 = 430ËšC, 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 = 430ËšC, 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.)2021-01-01T00:00:00ZDesign of 3D printed customisable post-stroke rehabilitation devices to provide a high-quality user experience/library/oar/handle/123456789/924182022-03-29T06:11:13Z2021-01-01T00:00:00ZTitle: 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.)2021-01-01T00:00:00ZThe use of recycled PET for high performance injection moulded components/library/oar/handle/123456789/923632022-03-29T06:02:12Z2021-01-01T00:00:00ZTitle: 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.)2021-01-01T00:00:00Z