One of the remits of the EPSRC early career forum (ECF) in manufacturing research is to foster collaborative research between its members. This article gives an overview of some of the collaborative projects currently taking place as a result of the formation of the ECF. Taken as a whole the projects are all based in manufacturing research, but the work spans a wide range of STEM disciplines, reflecting the diversity of the ECF membership. There are a total of six formally funded projects currently ongoing amongst the collaboration activities.
Direct Digital Fabrication: Integration of Advanced Manufacturing ProcessesDr Jon Shephard – Heriot-Watt University
Dr Robert Kay – University of Loughborough
Dr Patrick Smith – University of Sheffield
Dr Colm Connaughton – University of Warwick
Digital Fabrication is the direct manufacture of three-dimensional objects using additive or subtractive processes. It enables agile, on-demand and fully automated production in a wide range of manufacturing contexts and is a key enabling technology for future high-value manufacturing applications. Current Digital Fabrication technologies are limited in the range of materials which can be used, the processing speed, and the resolution available.
This project seeks to improve the ability to combine multiple materials e.g. metals and plastics, in a single process which at present is very restricted. This will be achieved by using a multi-process integration approach to Digital Fabrication where the best process for the application in hand can be selected. It combines the advantages of additive manufacturing, laser based processing and ink jet printing technologies to deposit and integrate different materials within each layer. Additionally, mathematical modelling will be employed to develop improved understanding of the physical processes governing these technologies.
The project addresses the fundamental scientific challenges required to interleave these different manufacturing techniques in order to achieve fine-grained control over the spatial distribution, microstructure and interface properties of the different materials to be laid down in each layer. These challenges include the integration of different Digital Fabrication processes, the use of configurable laser profiles to control droplet evaporation properties, and the use of laser-based surface texturing to improve the adhesion between the various layers and thus improve the overall mechanical properties of the part.
The project will provide the unpinning research to enable the production of three-dimensional structures from a range of materials. This academic team will work along with a consortium of industrial partners with strong track records in innovation for high value manufacturing applications.
In-situ monitoring of component integrity during additive manufacturing using optical coherence tomographyDr Kristian Groom – University of Sheffield
Dr Adam Clare – University of Nottingham
This project brings together researchers with complimentary skill sets in opto-electronic engineering, optical systems and precision manufacturing to meet the challenge of developing instrumentation for use in additive manufacturing. Advanced, in‐situ, real-time process control based on optical coherence tomography (OCT) will be applied to the additive manufacture of polymer parts. Application of this non-invasive imaging technique will bring additive manufacturing to the forefront of manufacturing capability with respect to product integrity, whilst also offering significant cost and resource savings.
Conventional imaging systems can only see surface topography, however OCT can see below the surface. A successful outcome of this project will be the realization of an OCT system capable of rapid analysis of the sub-surface structure (e.g. voids and composition) of additively manufactured parts composed of single or multiple plastics. A scheme will be developed for its incorporation into the additive manufacturing process whereby in-situ monitoring and real-time feedback and control is carried out to ensure process integrity is maintained.
Manufacturing Green Nanoparticles for Efficient Cell ManufactureDr Siddharth Patwardhan – University of
Dr Simon Kuhn – University College London
Dr Harish Bhaskaran – University of Oxford
Dr Robert Thomas – University of Loughborough
The material-cell interface is extremely useful in enabling exquisite control of cellular manufacturing. This project will develop new nature-inspired manufacture of bespoke green nanomaterials as substrates for cell growth. The green nanomaterials, which provide an environmentally friendly approach, are scalable and have promising biomedical applications. This project will establish the role of mixing in nanomaterials scale-up operations. By developing novel nano-probe techniques, this work will extensively investigate the material-cell interface.
This project aims to deliver large scale manufacturing of green nanomaterials suitable for cellular manufacture. This project involves collaborations across non-traditional disciplines involving nanomaterials chemistry, fluid dynamics, cell manufacturing and nanotechnology, and combining expertise from two EPSRC Centres for Innovative Manufacturing and two EPSRC Manufacturing Fellows.
Development of an optical system for on-line tracking of cell growth on microcarriersDr Karen Coopman – University of Loughborough
Dr Haydn Martin – University of Huddersfield
In order that people can live longer and lead more active lives there is a need to develop novel affordable and effective treatments for ill health. In some cases, cells that we have within our own bodies can be used to repair damaged tissues or organs. However, in adults, this repair mechanism is very limited and often inefficient so we may need to rely on cells from donors. Unfortunately, since it takes billions of cells to repair, for example the heart muscle of a heart-attack patient, we must isolate cells from donors and expand their numbers before they can be used for treatment. Currently it is possible to do this at the laboratory scale, generating for instance, millions of mesenchymal stem cells in a stirred tank over a period of 2 weeks.
However, as we consider how this will be achieved on a bigger manufacturing scale, we need to develop tools that will help us monitor and control the process to ensure the cells grown in this way are the same every time. This feasibility project combines the expertise of both biologists and engineers, to create an optical device that can monitor the growth of these cells in this stirred tank environment by giving the operator information about cell number and morphology.
This project will generate an optical device based on interferometry to image moving microcarriers within the stirred tank bioreactor. This approach moves away from the need to manually sample from the bioreactor and carry out off-line analysis in order to assess cell growth progression and morphology and when to supplement in additional microcarriers in order to maximise cell yield.
Particle Shape and Flow behaviour in Laser Sintering: from modelling to experimental validation (PASF)Dr Oana Ghita – University of Exeter
Dr Jin Sun – University of Edinburgh
This project proposes to investigate the way the polymeric powders of different shapes and sizes flow, interact and sinter in the Laser Sintering process, through modelling and experimental validation. Laser sintering is part of the additive manufacturing technology, known for its benefits in industries where custom made products, lightweight and complex designs are required. In laser sintering a polymer powder bed is heated to just below its melt temperature. A laser is then focused onto the bed which scans a raster pattern of a single layer of the final part. The bed lowers slightly and a new layer of powder is applied. The process is then repeated until the component is made and the additive layer process is complete. The spreading and compaction of the powder is an important part of the LS process, a non-uniform layer of powder leads to high porosity and weaker bonding between layers and therefore a structure with poor mechanical performance. Similarly, the size and shape of particles can change the sintering process. Larger contact areas between particles lead to a good sintering profile and ultimately to a high density part and good mechanical properties. Surface area of particles, polymer viscosity and surface tension are characteristics which will be considered when modelling the flow and sintering process.This project is highly innovative as it will unlock the materials limitations for polymeric laser sintering and will allow rapid expansion into a wider range of higher value applications due to lower powders costs, wider choices and better understanding of their behaviour within the manufacturing process.
In addition to the EPSRC funded collaborative research projects outlined above, ECF members Oana Ghita and Patrick Smith have collaborated on the following publication:
Beard JD, Stringer J, Ghita OR, Smith PJ. (2013) High Yield Growth of Patterned Vertically Aligned Carbon Nanotubes Using Inkjet-Printed Catalyst, ACS Applied Materials & Interfaces, volume 5 (19), pages 9785-9790, DOI:10.1021/am402942q.