Cranfield Conferences and Symposia

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Open Access
3D laser metal printing in zero gravity using additive manufacturing
(Cranfield University, 2019-05-09 10:12) Akhtar, Shariq
Poster presented at Cranfield University's 2019 Manufacturing Doctoral Community event.
Open Access
4D printing of Magnetic Shape Memory Alloys
(Cranfield University, 2022-01-14T15:44:56Z) Milleret, Anastassia
Magnetic shape memory alloys (MSMA) are ferromagnetic materials exhibiting a plastic reversible transformation when subjected to a magnetic field. This transformation occurs within few milliseconds, making them good candidates for ultra-fast actuators. Previous studies have reported an increase of the shape memory effect in bamboo-like Ni-Mn-Ga structures. Thus, 3D Printing, using Laser Powder Bed Fusion (l-PBF), is a potential manufacturing approach to fabricate near-net-shape textured MSMAs structures. This study investigates the influence of l-PBF process parameters (laser power, scan speed, hatch spacing and scanning strategy) on the relative density and the microstructure of bulk and lattice specimens made from a gas atomised Ni-Mn-Ga powder doped with excess Mn. The as-built bulk samples showed a high relative density, up to 98% with a homogenous 14M structure and a ferromagnetic behaviour. The residual porosity in the bulk material is mainly due to gas voids, lack of fusion and cracking. Fabrication of lattice structures at a low laser power (70W) and scan speed (450 mm/s) resulted in a significant decrease in cracking. The effect of process parameters on the strut’s geometry was also investigated, in addition the influence of the lattice geometries on the magnetic properties. Microstructural analysis revealed a layered microstructure with a stripe-like surface relief that originated from the presence of martensitic twins within the sample. Further work will focus on developing a new design to enhance the magnetic properties.
Open Access
4D Printing of Magnetic Shape Memory Alloys
(Cranfield University, 2020-12-02 11:40) Milleret, Anastassia
Magnetic shape memory alloys (MSMA) are ferromagnetic materials exhibiting a plastic reversible transformation. Compared to thermally activated shape memory alloys, such as NiTi, the response of MSMA is much faster (less than a millisecond), making them good candidates for actuators, sensors, micro pumps and energy harvesters. To date, the Ni-Mn-Ga system is the most studied MSMA, and is the focus of this study. The shape memory effect in MSMA is driven by a phase transformation from a high ordered austenitic Heusler phase to a lower symmetry martensitic phase. The change in the shape occurs within the martensitic phase in the presence of a magnetic field. This is due to the reorientation of the twin variants. The best magnetic shape memory effect was reported in single crystalline Ni-Mn-Ga exhibiting up to 10% strain. However, in the polycrystalline form, grain boundaries create obstacles for twin boundary motion and thus the shape memory effect is reduced. Nevertheless, recent studies show a high magnetic-field induced strain, up to 8.7%, in polycrystalline Ni-Mn-Ga foams. Increasing porosity and grain size decreases the grain boundary constraint. MSMAs foams can be made using ceramic space holders, by binder-jetting or by ink-printing. However, these techniques create random distribution and/or size porosity. Further investigations are required to control porosity and grain morphology to enhance the shape memory effect. In addition, magnetic properties are orientation-dependant. Previous studies have reported the possibility to control the grain orientation via laser-powder bed fusion (l-PBF) additive manufacturing technique by tuning the printing parameters and the scanning strategy. Thus, l-PBF appears to be a potential approach to create near-net shape oligocrystalline and foam-structure Ni-Mn-Ga.
Open Access
A holistic approach of Reconfigurable Manufacturing System (RMS) lifecycle
(Cranfield University, 2019-05-09 10:34) Tang, Jiecheng
Poster presented at Cranfield University’s 2019 Manufacturing Doctoral Community event.
Open Access
A Human Factors Evaluation of Mixed Reality Technologies for Command and Control Applications
(Cranfield University, 2018-01-03 09:56) Bibb, Christopher
Technical paper presented at the 2017 Defence and Security Doctoral Symposium.This research assesses the Human Factors aspects of adopting Mixed Reality (MxR) technologies for advanced interaction and visualisation techniques within future cockpit environments, where the role of the occupant is envisaged to change from that of a pilot to mission management specialist. Specifically, the work sets out to assess the impact on human perceptual-motor performance, cognition, workload and situational awareness of replacing physical display and control facilities with virtual alternatives. The use of fully virtual displays, viewed through a head-mounted display, allows for the rapid integration of new advanced sensor visualisation methods as well as supporting the tailoring of task-oriented bespoke interface layouts to the end user’s immediate (and dynamically changing) needs, in contrast to the rigid nature of physical displays. Furthermore, a virtual display can reduce the time and cost of changes/upgrades without incurring extensive physical modifications to the platform. When performing continuous gross input tasks, early results indicate that the MxR system promotes minor performance increases in response time when compared to existing systems (touchscreen and HOTAS input methods), with a reduced physical and cognitive workload over prolonged use. However, for complex interaction tasks, the MxR system was subjectively rated as a more cumbersome display and interface method.
Open Access
A Novel Fast Readout, Gamma Detector System for Nuclear Fingerprinting
(Cranfield University, 2017-11-15 12:01) Giroletti, Alessia; Velthuis, J.J.; Scott, T.
Technical paper presented at the 2017 Defence and Security Doctoral Symposium. In order to be effective, decommissioning of nuclear facilities as well as recovery procedures following a nuclear accident require a precise estimation of the amount, type, and topological distribution of nuclear material present at the scene. In this work we present a novel, fast readout, spectroscopy system suitable for high radiation level environment which we estimate to be 10 times faster than current deployed systems.The proposed device is based on semiconductor materials: when hit by a photon they generate electron-hole pairs, which in turn give rise to a current pulse that is proportional to the incident photon energy. This mechanism allows recognizing the incident radiation source. The proposed apparatus is composed of five semiconductor materials (Silicon, Gallium Arsenide, Uranium Dioxide, Cadmium Zinc Telluride and Diamond), which allow the cover the detection of a wide range of energies. This multi-material platform enables the precise identification of 27 isotopes which can be found after a nuclear accident or when a nuclear plant is in decommissioning. The amplifier stage uses the Amptek A250 charge sensitive preamplifier which shows low-noise (<100 electrons rms) and fast (rise time 2.5 ns) response behaviours. The readout chain consists of a MAROC3 chip and an FPGA (field programmable gate array). To prove the validity of the system, several Monte Carlo simulations, using Geant4, were performed. Simulation results have shown that gamma spectroscopy and material abundance study are possible. The system is under test at the present.
Open Access
A picture from thousands of words
(Cranfield University, 2020-01-08 15:08) Oishee, Kundu,
The UK government announced its intention to purchase aircraft carriers in July 1998 and in December 2017 the first of the two ships were delivered to the Royal Navy. Newspaper reports on the procurement of the Queen Elizabeth class aircraft carriers have varied in their sentiment over the two decades- sometimes expressing positive, congratulatory emotions of pride and joy and at other times expressing criticism, anger, and despair at project management and outcomes. The image is a normalized plot of sentiment scores associated with 2,688 articles published in eleven British newspapers (broadsheets and tabloids) between 1998 and 2018, where sentiment scores have been calculated using the sentimentr package in R. This research method allows viewing project history at a glance, identifying and investigating critical periods of success and failure, accounting for wider public opinion towards public projects, and extracting greater meaning from textual data with speed and consistency.
Open Access
A review of simulation modelling approaches in aviation spare parts inventory optimisation
(Cranfield University, 2024-06-07) bin Mohammud, Zaki; Fan, Ip-Shing; Avdelidis, Nicolas P.
Aviation spare parts are expensive and are being kept as a buffer for unscheduled and scheduled maintenance activities. Apart from cash flow being locked in the inventory, spare parts for aircraft or helicopters are also critical in the continuous operations of air assets. In addition, the holding cost is roughly 20 per cent of the total inventory value. Holding costs are costs such as insurance, utilities and manpower. Minimising the total inventory value could be done by adopting a lower inventory count through various methods, such as the provision of spare parts, which can be done either by forecasting the failure of components or by using new maintenance methodologies, such as predictive maintenance. The methods have been used widely in the aviation industry for a long time. The upward trend of papers published from 1963 to 2023 shows that aviation spare parts optimisation is still being discussed. This paper reviews the simulation modelling approaches to optimise aviation spare inventory. 221 papers were reviewed from Scopus and Web of Science (WoS) literature databases, and 17 papers from 1982 to 2023 were chosen based on the simulation modelling approach, such as System Dynamics and Discrete-Event Simulation. The papers were classified according to simulation modelling techniques, spare parts and operations classification, and challenges and opportunities.
Open Access
A Standard European Tank? Technology Transfer and the Quest since 1945 for a Joint International Main Battle Tank within Europe and NATO
(Cranfield University, 2017-11-15 11:53) Cubbin, Mike
Poster presented at the 2017 Defence and Security Doctoral Symposium.International cooperation in defence has long been a feature of diplomacy, and there are many theoretical advantages to both international technology transfer and standardisation within military alliances, from military organisation and logistics to political consolidation, and on to economic savings in both development and production. International collaboration in the defence industry has produced many successful weapon systems, from technologically advanced fighter aircraft to anti-tank missiles. Given the success of many joint defence projects such as the Tornado and Eurofighter aircraft, and the Roland and Brimstone missile systems, the question emerges as to why there have been no successful collaborative international main battle tank projects. The quest for a standard tank design within NATO began with the Franco-German ‘standard European tank’ project in 1956, and NATO countries have since made several further attempts towards a joint Main Battle Tank (MBT) design. At the time of writing there is talk of yet another potential joint European tank project, this time between France, Germany and possibly Poland. An important question that arises from the many works on armoured warfare, armoured vehicle technology and military technology transfer then is, why has NATO yet to agree and produce a standard tank despite several attempts since 1945? To date, there has been only one successful truly collaborative main battle tank design, and that was the Anglo-American Mark VIII ‘International’ in 1917.
Open Access
A Standard European Tank? Technology Transfer and the Quest since 1945 for a Joint International Main Battle Tank within Europe and NATO
(Cranfield University, 2017-11-15 12:02) Cubbin, Mike
3MT presented at the 2017 Defence and Security Doctoral Symposium.International cooperation in defence has long been a feature of diplomacy, and there are many theoretical advantages to both international technology transfer and standardisation within military alliances, from military organisation and logistics to political consolidation, and on to economic savings in both development and production. International collaboration in the defence industry has produced many successful weapon systems, from technologically advanced fighter aircraft to anti-tank missiles. Given the success of many joint defence projects such as the Tornado and Eurofighter aircraft, and the Roland and Brimstone missile systems, the question emerges as to why there have been no successful collaborative international main battle tank projects. The quest for a standard tank design within NATO began with the Franco-German ‘standard European tank’ project in 1956, and NATO countries have since made several further attempts towards a joint Main Battle Tank (MBT) design. At the time of writing there is talk of yet another potential joint European tank project, this time between France, Germany and possibly Poland. An important question that arises from the many works on armoured warfare, armoured vehicle technology and military technology transfer then is, why has NATO yet to agree and produce a standard tank despite several attempts since 1945? To date, there has been only one successful truly collaborative main battle tank design, and that was the Anglo-American Mark VIII ‘International’ in 1917.
Open Access
A survey framework for setting an Augmented Reality (AR) roadmap in rolling stock organizations
(Cranfield University, 2024-06-07) Scheffer, Sara; Abbas Yawar
In anticipation of Industry 4.0’s significant impact on future maintenance systems, Augmented Reality (AR) emerges as a key technology. Even though AR has proven to be mature and applicable in maintenance practices, its practical implementation and challenges faced by organizations remain understudied. The integration of AR into organizational systems poses a crucial challenge, necessitating novel maintenance strategies, interdepartmental collaboration, and clearly defined goals. This research addresses the impact of AR on organizations, emphasizing the need for organizational readiness and adaption in maintenance processes, AR technology adoption, and IT infrastructure integration. This research demonstrates the development of an AR roadmap for rolling stock organizations through the application of a comprehensive survey framework. The study is based on a dual-pronged approach, incorporating a maturity and readiness assessment to ascertain the current state of AR adoption and organizational readiness. The survey framework systematically evaluates critical aspects such as existing technology infrastructure, operator skills, challenges faced, and desired organizational outcomes. The survey findings contribute to developing a tailored AR roadmap that addresses the specific needs and challenges of rolling stock maintenance operations. This research aims to enhance AR integration in rolling stock organizations and provides a practical guide for effective implementation.
Open Access
A sustainability-based framework for predicting the remaining useful life of a complex engineering asset
(Cranfield University, 2024-06-07) Venkata Subhadua, Vaishnav; Ali, Zain; Farsi, Maryam; Norton, Andy
As climate change became recognised as a major global challenge, the ability to define and account for the environmental performance of an asset became an important attribute aiding the sustainable development strategies towards net-zero. Remaining Useful Life (RUL) indicator allows for optimised maintenance scheduling and the life extension of an asset. However, the existing RUL prediction methods do not fully consider the environmental performance (EP) of an asset. This paper aims to develop a sustainability-based framework for complex engineering assets’ RUL prediction based on a systematic review of key literature. The proposed framework introduces a new concept, so-called ‘sustainable-RUL’ (SRUL), which refers to the estimated remaining lifetime that an item is able to function reliably and be environmentally sustainable. The Scopus database is used to develop the PRISMA framework. Finally, a generic S-RUL framework is introduced which incorporates the environmental sustainability aspect into the RUL prediction. Hence, the decision-maker is provided with a single predictive indicator, that accounts for the asset reliability and EP at the same level of granularity, thus facilitating the selection of maintenance policies that establishes a condition for ecological and economic stability.
Open Access
A Taxonomy for Contrasting Industrial Control Systems Asset Discovery Tools
(Cranfield University, 2022-11-24T17:33:43Z) Samanis, Manolis
The number of tools for scanning industrial assets has grown considerably over the past decade. There is currently a plethora of free and commercial asset scanning tools which specialize in industrial control system (ICS) devices. However, to the best of our knowledge, there is no information pertaining to their actual capabilities and no experimental comparative comparison of their features. Moreover, it is not clear to what depth of scanning these tools can reach and whether the tools are suitable to use in a scaled industrial network architecture. This poster provides the first systematic features comparison available on free to use asset scanning tools, on the basis of an ICS scanning taxonomy we propose. Based on the taxonomy, we investigate tools scanning depth and validate results through experimentation on Siemens and Allen Bradley devices.
Open Access
A Thin and Structured Acoustic Metamaterial for Absorption of Airborne Sound
(Cranfield University, 2017-01-24 16:22) Starkey, Tim
Poster presented at the 2016 Defence and Security Doctoral Symposium.Achieving precise control over the propagation of sound energy has far reaching implications in both airborne and underwater environments. Obtaining a high level of control in the reflection, transmission, and absorption characteristics of sound is a significant challenge in the realisation of the next generation of sonar, acoustic imaging, acoustic cloaking, and sound attenuating devices.Traditionally the control of sound through a medium is governed by the bulk material properties of the fluid or the solid with which the sound is interacting. The bulk modulus and mass density are often the key parameters, but also the limiting factors in many acoustic engineering problems; for instance, it is impossible to absorb low frequency sound with a traditional (bulk) thin lightweight material.One route to overcome these limitations is to design and fabricate bespoke acoustic ‘metamaterials’ to control, guide, or otherwise manipulate the propagation of acoustic energy. These metamaterials are usually composite materials that comprise structured elements that exhibit periodic or geometric features with physical dimensions that are smaller than the wavelength of sound. The collective behaviour of the structured ensemble can be tuned to produce completely artificial behaviours that would not otherwise be seen using naturally occurring materials. At present there is a rapid expansion in acoustic metamaterial research, with studies demonstrating the potential utility these materials will have in a variety of technological applications.In this poster, I will show how sound absorption by an acoustic metamaterial can be achieved by exploiting the thermos-viscous boundary layer. This boundary layer is created at the interface between air and a solid material due to the ‘non-slip’ boundary condition for sound propagating in the direction tangential to the interface. Our metamaterial comprises a perforated (holey) metal plate separated from a flat surface by a small air gap. The sound attenuation in this structure is strongly dependent on the thickness of the air gap. By using this approach, sound absorbers that are significantly thinner and lighter than conventional sound absorbing panels may be realised.
Open Access
Absence of Presence
(Cranfield University, 2020-01-10 08:45) Binti zulkifli, Safiah
The tiny the object, the more difficult it is to detect. Failed to detect does not simply signifies the absence of presence. The object may be camouflage and immersed in this huge world - as this image demonstrates! With a booming micro-drones easily available for all walks of life, it is hugely possible for these drones to perform stealthy surveillance being unnoticeable. But, wait! This fact can be avoidable with a specifically design radar for a micro-size target detection. By extracting micro-Doppler signature which is induced by mechanical vibration or rotation from a target – in this case is the flapping wings enable the presence more significant and visible. It is the time to monitor the usage of this presence to avoid illegal and illicit activities for further exploitation. Full control of the latest technology ensure the harmonic and peaceful environment.
Open Access
Accurate, fast and stable solver for electromagnetic scattering of absorbing layer materials
(Cranfield University, 2016-12-06 11:26) Dély, Alexandre
Poster presentation at the 2016 Defence and Security Doctoral Symposium. The boundary element method is an efficient and flexible tool for the modelling of scattering of electromagnetic waves by conducting and penetrable objects. It finds applications in the solution of forward and inverse problems in e.g. radar footprint determination, stealth technology, and imaging for diagnostics and security. To model scattering by objects that are for almost perfectly conducting, the classic equations are augmented with a so called impedance boundary condition (IBC). The IBC specifies a relationship between the electric field and the magnetic field on the surface of the scatterer, or equivalently between the magnetic and electric currents. IBC applications are numerous: especially they are well suited to simulate metals coated by a dielectric/absorbing layer which is the base of stealth technologies. In this contribution, an IBC enabled electric field integral equation will be introduced that can provide accurate results in linear time complexity at arbitrarily low frequency. The starting point of this work is the classic IBC formulation. Unfortunately, this suffers from low frequency and dense grid breakdowns. This means that the accuracy of the solution deteriorates and/or the computation time increases, when the frequency is low and/or when the number of unknown of the problem is high, because the iterative solvers used to solve the linear system require more iterations. The new IBC-EFIE introduced in this work does not suffer from these problems and can deliver highly accurate solutions at arbitrary frequency in near linear computational complexity. The formulation is based on quasi Helmholtz decomposition techniques and multiplicative preconditioners and yields a system whose condition number is independent of both the frequency and the discretization density.
Open Access
Achieving Effective Innovation Based On TRIZ Technological Evolution
(Cranfield University Press, 2009-03-31) Sun, J. G.; Tan, R. H.; Cao, G. Z.; Rajkumar Roy; Essam Shehab
This paper outlines the conception of effective innovation and discusses the method to achieve it. Effective Innovation is constrained on the path of technological evolution so that the corresponding path must be detected before conceptual design of the product. The process of products technological evolution is a technical developing process that the products approach to Ideal Final Result (IFR). During the process, the sustaining innovation and disruptive innovation carry on alternately. By researching and forecasting potential techniques using TRIZ technological evolution theory, the effective innovation can be achieved finally.
Open Access
Achieving workplace inclusiveness by using ergonomics risk assessment
(Cranfield University Press, 2013-09-19) Hussain, Amjad; Case, Keith; Marshall, Russell; Summerskill, Steve
Traditional manufacturing work practices do not consider human variability issues during the design process. However, most manual assembly activities demand high levels of repetition and speed without compromising product quality and work productivity. Individual factors including age, gender, skill, experience and anthropometry cause variations in task strategies that lead to variations in individual and organizational work performance. The ergonomics-based risk assessment methods OWAS, REBA and RULA have been used to evaluate risk levels associated with working methods. This paper discusses the need for these methods to understand and highlight the key issues generated by these variations with the objective of minimizing these variations. Methods that can be used to promote working strategies that minimize the level of risk are described. The proposed research method potentially reduces work-related musculoskeletal disorders, injuries, pain, and promotes safe, healthy, productive and more inclusive working strategies suitable for a diverse working population.
Open Access
Acoustic Interface States via Material Variation
(Cranfield University, 2020-01-07 15:05) Pearce, Benjamin
Interface states at the boundary between two phononic crystals can arise when the two crystals possess overlapping bandgaps and differing signs in the imaginary components of their impedance [1]. The suitability of a given pair of crystals when designing an interface system can be inferred from the parity of the supported standing edge states marking the beginning and end of their band gap [2]. A crystal that supports a standing wave with an even parity pressure distribution at the beginning of its band gap will possess a differing imaginary impedance sign to a crystal supporting an odd parity state at the start of its band gap [2]. Previous works [1,2,3] have designed such systems by varying the geometry of a crystal, such variations result in the band gap of the crystal closing and re-opening, leading to two crystals with geometries that place them either side of a band gap closure. This will meet the previously given criteria for exhibiting an interface state [3]. The present study uses a variation of materials within a phononic crystal to demonstrate an interface system, whilst maintaining a consistent geometry between the two crystals. FEM Modelling was performed, using the commercial COMSOL software, to show that variations in the material properties of one of the materials within a phononic crystal results in an analogous process of band gap opening and closing. Two, two component 1D phononic crystals consisting of alternating layers of materials ‘A’ and ‘B’ were then designed and modelled to confirm the parity of their band gap edge states. Material ‘A’ was set as 3 mm thick ABS plastic, whilst material ‘B’ was either water or aluminium with thickness of 0.3 mm. The crystals were numerically modelled to provide the transmission spectra both individually and as a combined interface system revealing the predicted presence of an interface state. Initial experimental confirmation is underway, with a preliminary sample of an ABS/water crystal having been constructed, and its transmission spectrum obtained. Results thus far show the presence of the expected modes and a band gap. Further investigations are now underway using an improved sample so that data may be better compared with modelling.References:1. Xiao, M., Zhang, Z. Q., & Chan, C. T. (2014). Surface impedance and bulk band geometric phases in one-dimensional systems. Physical Review X, 4(2), 1–12. 2. Meng, Y., Wu, X., Zhang, R. Y., Li, X., Hu, P., Ge, L., Wen, W. (2018). Designing topological interface states in phononic crystals based on the full phase diagrams. New Journal of Physics, 20(7). 3. Xiao, M., Ma, G., Yang, Z., Sheng, P., Zhang, Z. Q., & Chan, C. T. (2015). Geometric phase and band inversion in periodic acoustic systems. Nature Physics, 11(3), 240–244.
Open Access
Adaptations to unaccustomed resistance training for women in physically demanding occupations
(Cranfield University, 2020-01-09 15:41) McGuire, Stephen
Improvements in maximal strength may reduce injury risk and improve occupational performance. Women’s naturally lower muscular strength compared to men, can be offset through resistance training (RT), but research into its implementation has been limited. Therefore, the time-course of muscular adaptations is of interest, with evidence suggesting adaptations in size and strength are detectable as early as 3-4 weeks, concomitant with an attenuation of RT induced muscle damage. This evidence offers a reduction in the time commitment of RT that may enhance readiness for physically demanding activity, but functional adaptations have yet to be explored. The purpose of this thesis is to explore measurement techniques, moderators of baseline variation and responses to unaccustomed heavy-load RT in civilian women representative of individuals entering physically demanding occupations. Specifically, high reliability and acceptable validity as a measure of maximal strength was established for the isometric mid-thigh pull, now a UK Armed Forces entrance test, in non-athlete females. Next, the influence of physical characteristics, previous sporting activity, and single nucleotide polymorphisms on variation in strength was assessed. The ongoing final study aims to assess the efficacy of a 4-week heavy compound RT program on improving performance and biochemical adaptations.