Additive manufacturing (AM) is projected to require 60,000 jobs in the UK by 2025, but there are a series of barriers to the industrial application. One of the most problematic is non-comprehensive knowledge in design for AM (DfAM). This study aims to test the effect of two undergraduate DfAM teaching approaches. A visual and audial approach (design lecture) and a kinaesthetic, problem-based learning (PBL) approach (manufacturing laboratory) were compared against technical and participant perspective criteria to assess the learning, engagement, and self-efficacy of the students. The participants were set a DfAM challenge; to redesign a bracket. The technical merits of the designs were evaluated after teaching through a design lecture alone or after a design lecture and manufacturing-laboratory. The participant’s perspective was evaluated at the end of the study. The groups who undertook both the design lecture and manufacturing laboratory showed a mean technical mark of 100% for criteria (C) 13 (“Parts have been consolidated into one part”), 91.7% for C14 (“The bracket is hollowed where possible”) and 100% for C16 (“Manufacture was successful”). These technical marks demonstrate a statistically significant increase over those of the groups who undertook the design lecture alone. The participant evaluation reinforced this result; the manufacturing laboratory was chosen more frequently in answer to questions on applicability (Q13 = 83%), preparedness (Q15 = 83%), and gaining confidence in DfAM (Q31 = 74%). This study demonstrates the importance of PBL in DfAM, both to increase technical aptitude of the student (creativity and manufacturing) and their perspective on their own learning and self-efficacy.

Integration of advanced technologies have revitalised treatment methods in the current clinical practice. In orthopaedic surgery, patient-specific implants have leveraged the design freedom offered by additive manufacturing (AM) exploiting the capabilities within powder bed fusion processes. Furthermore, generative design (GD), a design exploration tool based on the artificial intelligence, can integrate manufacturing constraints in the concept development phase, consequently bridging the gap between AM design and manufacturing. However, the reproducibility of implant prototypes are severely constrained due to uncomprehensive information on manufacturing and post processing techniques in the detailed design phase. This paper explores the manufacturing feasibility of novel GD concept plate designs for High Tibial Osteotomy (HTO), a joint preserving surgery for a patient diagnosed with osteoarthritis in the knee. A design for AM (DfAM) workflow for a generatively designed HTO plate is presented, including; detailed DfAM of GD concept designs, fabrication of plate prototypes using electron beam powder bed fusion (PBF-EB) of medical grade Ti-6Al-4 V, post processing and inspection. The study established PBF-EB as a suitable manufacturing method for the highly complex GD plate fixations, through evaluating the impact of manufacturing and post processing on the surface finish and geometrical precision of the plate design features.

Additive manufacturing (AM) is expected to generate huge economic revenue by 2025; however, this will only be realised by overcoming the barriers that are preventing its increased adoption to end-use parts. Design for AM (DfAM) is recognised as a multi-faceted problem, exasperated by constraints to creativity, knowledge propagation, insufficiencies in education and a fragmented software pipeline. This study proposes a novel approach to increase the creativity in DfAM. Through comparison between DfAM and in utero human development, the unutilised potential of design through the time domain was identified. Therefore, the aim of the research is to develop a computer-aided manufacturing (CAM) programme to demonstrate design through the time domain, known as Temporal DfAM (TDfAM). This was achieved through a bespoke MATLAB code which applies a linear function to a process parameter, discretised across the additive build. TDfAM was demonstrated through the variation of extrusion speed combined with the infill angle, through the axial and in-plane directions. It is widely accepted in the literature that AM processing parameters change the properties of AM materials. Thus, the application of the TDfAM approach offers the engineer increased creative scope and control, whilst inherently upskilling knowledge, in the design of AM materials.

The clinical diagnosis of atherosclerosis via the measurement of stenosis size is widely acknowledged as an imperfect criterion. The vulnerability of an atherosclerotic plaque to rupture is associated with its mechanical properties. The potential to image these mechanical properties using magnetic resonance elastography (MRE) was investigated through synthetic datasets. An image of the steady state wave propagation, equivalent to the first harmonic, can be extracted directly from finite element analysis. Inversion of this displacement data yields a map of the shear modulus, known as an elastogram. The variation of plaque composition, stenosis size, Gaussian noise, filter thresholds and excitation frequency were explored. A decreasing mean shear modulus with an increasing lipid composition was identified through all stenosis sizes. However the inversion algorithm showed sensitivity to parameter variation leading to artefacts which disrupted both the elastograms and quantitative trends. As noise was increased up to a realistic level, the contrast was maintained between the fully fibrous and lipid plaques but lost between the interim compositions. Although incorporating a Butterworth filter improved the performance of the algorithm, restrictive filter thresholds resulted in a reduction of the sensitivity of the algorithm to composition and noise variation. Increasing the excitation frequency improved the techniques ability to image the magnitude of the shear modulus and identify a contrast between compositions. In conclusion, whilst the technique has the potential to image the shear modulus of atherosclerotic plaques, future research will require the integration of a heterogeneous inversion algorithm.

Design techniques represent a huge economic barrier to the progression of Additive Manufacturing (AM) to more industrial applications. The aim of this research is to use biological analogies, taken from human development to offer a new perspective on what the definition of additive design and manufacturing could encompass in the future. Efficient design for additive manufacturing requires increased creativity, something that is currently constrained by the psychological inertia imposed by a history of subtractive manufacturing. The development of the human, i.e. the differentiation and proliferation of cells to form tissues and organs, creates an organism that develops and functions in synergy. This may be considered the epitome of sophisticated AM. In this study, a novel methodology, utilising the Theory of Inventive Problem Solving, was applied to develop bottom-up analogies between the two systems. A detailed biological discussion of human development is presented, offering a vision of how AM could begin to reflect the synergy displayed during the growth of the foetal form. The results propose a series of developments to current design methods and manufacturing systems for AM. In-situ design for AM is projected as an innovative methodology of expanding design freedom to incorporate temporal stimuli and material response through space and scale across the build envelope. Manufacturing technologies under the themes of Hybrid, Suspended, Perfusion and Diffusion Manufacturing are proposed from insight taken from the development of the foetal bones, amniotic fluid, cardiovascular system and the function of the placenta and fast block polyspermy.