George Jeronimidis

George Jeronimidis
University of Reading · School of Construction Management and Engineering

About

89
Publications
18,785
Reads
How we measure 'reads'
A 'read' is counted each time someone views a publication summary (such as the title, abstract, and list of authors), clicks on a figure, or views or downloads the full-text. Learn more
3,172
Citations

Publications

Publications (89)
Conference Paper
Full-text available
This paper analyses the effect of façade curvature with varying the surrounding building heights on pedestrian-level wind speeds and comfort for walking, using computational fluid dynamics. The case study focuses on 20 Fenchurch Street site in London as several complaints have risen in relation to high wind speeds, the cause of which is not thoroug...
Conference Paper
Full-text available
The constant increase in urban populations at the centre of large cities increases the demand for residential developments. Whilst the construction of tall buildings solves many of the housing crises, they introduce several environmental challenges. Accelerating winds at pedestrian level through down-drafting, flow channelling and corner accelerati...
Article
Changes to the angular position of the vibrating floating mass transducer (FMT) coupled to the long process of the incus will not affect stapes velocity. The MED-EL Vibrant Soundbridge is an active middle ear implantable device, which constitutes an effective alternative to acoustic hearing aids for the rehabilitation of patients with sensorineural...
Article
What can we learn from the spatial logic of collections of trees in the rainforest? Evan Greenberg of the EmTech programme at the Architectural Association (AA) School of Architecture in London and George Jeronimidis of the Centre for Biomimetics at the University of Reading combine forces to analyse the rainforest's morphology and its potential as...
Article
Biomechanical properties of squid suckers were studied to provide inspiration for the development of sucker artefacts for a robotic octopus. Mechanical support of the rings found inside squid suckers was studied by bending tests. Tensile tests were carried out to study the maximum possible sucking force produced by squid suckers based on the streng...
Conference Paper
Two types of tactile sensors were developed to detect normal contact for a soft bodied robot inspired by octopus. The first type was fabricated using quantum tunnelling composite (QTC) materials. Under pressure, the material transforms from an insulator to a conductor. Electrolycra was used to connect the QTC pills to wires. The second type of sens...
Article
In order to fabricate a biomimetic skin for an octopus inspired robot, a new process was developed based on mechanical properties measured from real octopus skin. Various knitted nylon textiles were tested and the one of 10-denier nylon was chosen as reinforcement. A combination of Ecoflex 0030 and 0010 silicone rubbers was used as matrix of the co...
Conference Paper
Presented in this paper are two types of contact sensors developed for an octopus inspired robot. The first type was fabricated using QTC pills. The second type is a soft sensor composed of a thin silicone rubber plate sandwiched between two electrolycra sheets. There is a hole at the centre of the silicone plate. Under contact force, both types of...
Conference Paper
Biomechanical properties of squid suckers have been studied. The stiffness of the sucker rings was measured. Sucking force at sea level and maximum possible sucking force were obtained by using specially-designed tensile tests. Two biomimetic passive suckers were developed based on the studies of the squid sucker. The first one was a direct copy of...
Conference Paper
Octopus skin was characterized to set design criteria for the artificial skin of an octopus-inspired robot. Young’s moduli, failure strain and ultimate stress were obtained via uniaxial tensile tests. The fracture toughness of the skin was measured by using scissors cutting tests. Silicone rubber is waterproof and has a failure strain higher than 5...
Article
soft skin artefacts made of knitted nylon reinforced silicon rubber were fabricated mimicking octopus skin. A combination of ecoflex 0030 and 0010 were used as matrix of the composite to obtain the right stiffness for the skin artefacts. Material properties were characterised using static uniaxial tension and scissors cutting tests. Two types of ta...
Article
This paper presents a completely new design of a bogie-frame made of glass fibre reinforced composites and its performance under various loading conditions predicted by finite element analysis. The bogie consists of two frames, with one placed on top of the other, and two axle ties connecting the axles. Each frame consists of two side arms and a tr...
Article
Full-text available
Architecture and construction are highly interdisciplinary fields, integrating many professions and many disciplines on different levels of scale and complexity. Studies of natural systems have at all times been inspirational for design. Investigating the overlaps between biology and architecture we find that a biological paradigm inspires the curr...
Article
The paper describes results of an experimental programme carried out as one of the essential phases of the implementation of a EUREKA project EUROBOGIE, which is aimed at development of advanced vehicle bogies and has a great potential to lead to more efficient movement of freight and passengers with lower environmental impact. The aim of the proje...
Article
Full-text available
Movement in biology is an essential aspect of survival for many organisms, animals and plants. Implementing movement efficiently to meet specific needs is a key attribute of natural living systems, and can provide ideas for man-made developments. If we had to find a subtitle able to essentially convey the aim of this special section, it could read...
Article
Octopus skin samples were tested under quasi-static and scissor cutting conditions to measure the in-plane material properties and fracture toughness. Samples from all eight arms of one octopus were tested statically to investigate how properties vary from arm to arm. Another nine octopus skins were measured to study the influence of body mass on s...
Article
In order to develop skin artefact for an octopus-inspired robot arm, which is designed to be able to elongate 60% of its original length, silicone rubber and knitted nylon sheet were selected to manufacture an artificial skin, due to their higher elastic strain and high flexibility. Tensile and scissors cutting tests were conducted to characterise...
Article
This paper presents the results of quasi-static and dynamic testing of glass fiber-reinforced polyester leaf suspension for rail freight vehicles named Euroleaf. The principal elements of the suspension’s design and manufacturing process are initially summarized. Comparison between quasi-static tests and finite element predictions are then presente...
Article
Full-text available
Viscous coupling between filiform hair sensors of insects and arthropods has gained considerable interest recently. Study of viscous coupling between hairs at micro scale with current technologies is proving difficult and hence the hair system has been physically scaled up by a factor of 100. For instance, a typical filiform hair of 10 mum diameter...
Article
Full-text available
The importance of biological materials has long been recognized from the molecular level to higher levels of organization. Whereas, in traditional engineering, hardness and stiffness are considered desirable properties in a material, biology makes considerable and advantageous use of softer, more pliable resources. The development, structure and me...
Article
The aim of this study was to investigate the impact of cochlear implant electrode insertion on middle-ear low frequency function in humans. Preservation of residual low frequency hearing with addition of electrical speech processing can improve the speech perception abilities and hearing in noise of cochlear implant users. Preservation of low frequ...
Article
The mechanism of active stress generation in tension wood is still not fully understood. To characterize the functional interdependency between the G-layer and the secondary cell wall, nanostructural characterization and mechanical tests were performed on native tension wood tissues of poplar (Populus nigra x Populus deltoids) and on tissues in whi...
Article
Investigation of the fracture mode for hard and soft wheat endosperm was aimed at gaining a better understanding of the fragmentation process. Fracture mechanical characterization was based on the three-point bending test which enables stable crack propagation to take place in small rectangular pieces of wheat endosperm. The crack length can be mea...
Article
Full-text available
The paper presents results of a partial experimental programme carried out within the project EUREKA E! 2462 TRUS, which aim is to demonstrate a novel form of hybrid electric drive line without the need for overhead lines. The zero emissions public transport vehicle is based on a hybrid electric drive line with novel, strongly innovative features....
Article
A fully automated procedure to extract and to image local fibre orientation in biological tissues from scanning X-ray diffraction is presented. The preferred chitin fibre orientation in the flow sensing system of crickets is determined with high spatial resolution by applying synchrotron radiation based X-ray microbeam diffraction in conjunction wi...
Article
Inadvertent drilling on the ossicular chain is one of the causes of sensorineural hearing loss (HL) that may follow tympanomastoid surgery. A high-frequency HL is most frequently observed. It is speculated that the HL is a result of vibration of the ossicular chain resembling acoustic noise trauma. It is generally considered that using a large cutt...
Article
This paper presents the design evolution process of a composite leaf spring for freight rail applications. Three designs of eye-end attachment for composite leaf springs are described. The material used is glass fibre reinforced polyester. Static testing and finite element analysis have been carried out to obtain the characteristics of the spring....
Article
ABSTRACTA close examination of mechanical “noise” produced during the cutting of potato tuber parenchyma tissue suggested that the signals reflected the summation of the stretching and breaking of individual cell walls. Replacement of the cutting blade by a thin parallel-sided glass probe, together with the use of very sensitive load- and deflectio...
Article
The stress relaxation behaviour of two frozen sucrose solutions (7% and 19%) during indentation in the temperature range of -20C to -40C were investigated. The stress relaxation is similar to that of pure polycrystalline ice, which is controlled by steady-state creep. The steady state creep rate exponent, m, of 7% and 19% sucrose solutions lies bet...
Article
Full-text available
Direct measurement of strain field in a mechanically loaded Norway spruce branch–stem junction was performed by means of electronic speckle pattern analysis. Results were compared with strain distribution in a polyester cast of identical shape as the branch–stem junction, and a simplified polyester model consisting of two half-cylinders. Compared t...
Article
Full-text available
Cercal hairs represent in cricket a wind sensitive escape system, able to detect the airflow generated from predating species. These sensors have been studied as a biomimetic concept to allow the development of MEMS for biomedical use. In particular, the behaviour of the hairs, including airflow response, resonant frequency and damping, has been in...
Article
Full-text available
Quality control on fruits requires reliable methods, able to assess with reasonable accuracy and possibly in a non-destructive way their physical and chemical characteristics. More specifically, a decreased firmness indicates the presence of damage or defects in the fruit or else that the fruit has exceeded its "best before date", becoming unsuitab...
Article
Full-text available
An adaptive tuned vibration absorber (ATVA) with a smart variable stiffness element is capable of retuning itself in respons to a time-varying excitation frequency, enabling effective vibration control over a range of frequencies. This paper discusse novel methods of achieving variable stiffness in an ATVA by changing shape, as inspired by biologic...
Article
This paper summarizes the design, manufacturing, testing, and finite element analysis (FEA) of glass-fibre-reinforced polyester leaf springs for rail freight vehicles. FEA predictions of load-deflection curves under static loading are presented, together with comparisons with test results. Bending stress distribution at typical load conditions is p...
Article
Full-text available
In this work, compliant actuators are developed by coupling braided structures and polymer gels, able to produce work by controlled gel swelling in the presence of water. A number of aspects related to the engineering of gel actuators were studied, including gel selection, modelling and experimentation of constant force and constant displacement be...
Article
The aim of this study was to measure the mass loading effect of an active middle-ear implant (the Vibrant Soundbridge) in cadaver temporal bones. Implantable middle ear hearing devices such as Vibrant Soundbridge have been used as an alternative to conventional hearing aids for the rehabilitation of sensorineural hearing loss. Other than the obviou...
Article
Full-text available
The realisation that much of conventional, modern architecture is not sustainable over the long term is not new. Typical approaches are aimed at using energy and materials more efficiently. However, by clearly understanding the natural processes and their interactions with human needs in view, designers can create buildings that are delightful, fun...
Article
Full-text available
Partial substitution of glass fibers with natural fibers in composites to measure the effect on falling weight was performed. Flax-epoxy laminates (dimensions 250 × 25 × 10mm ) were obtained by hand lay-up using different flax thread sizes (0.2, 0.9, and 2.3 mm). Quasi-static three-point bending tests was performed on an INSTRON 4302 testing machin...
Article
This paper shows the process of the virtual production development of the mechanical connection between the top leaf of a dual composite leaf spring system to a shackle using finite element methods. The commercial FEA package MSC/MARC has been used for the analysis. In the original design the joint was based on a closed eye-end. Full scale testing...
Article
Samples of Norway spruce wood were impregnated with a water-soluble melamine formaldehyde resin by using short-term vacuum treatment and long-term immersion, respectively. By means of Fourier transform infrared (FTIR) spectroscopy and UV microspectrophotometry, it was shown that only diffusion during long-term immersion leads to sufficient penetrat...
Article
It has been proposed in the literature that the penetration of resin compounds into the wood cell wall may enhance the durability of adhesive bonds. In the study presented here, the diffusion of resin compounds into the cell wall of two systems, phenol–formaldehyde (PF) and polymeric methylene di-phenyl-di-isocyanate (pMDI), respectively, was evalu...
Article
Composite sheets reinforced with wood pulp fibers were produced using Melamine formaldehyde (MF) resins for investigating the basic mechanical properties of the composites. The MF-impregnated sheets were cured at a temperature of 120°C in a hot press for 10 minutes under a pressure of 20 MPa to obtain a white to yellowish composite sheets of 1.2 mm...
Article
Xyloglucan-acting enzymes are believed to have effects on type I primary plant cell wall mechanical properties. In order to get a better understanding of these effects, a range of enzymes with different in vitro modes of action were tested against cell wall analogues (bio-composite materials based on Acetobacter xylinus cellulose and xyloglucan). T...
Article
In this paper we focused on the differences of mechanical properties of tension and normal wood of 1-year-old poplar trees, artificially tilted. Elastic and fracture properties have been measured and linked to the anatomy. Tension wood is well known because it prevents good surface finishing and leads to difficulties with sawing. We studied three m...
Article
Why it is easier to cut with even the sharpest knife when pressing down and sliding than when merely pressing down alone is explained. A variety of cases of cutting where the blade and workpiece have different relative motions is analysed and it is shown that the greater the slice/push ratio given by (blade speed parallel to the cutting edge/blade...
Article
The presence of mechanical anisotropy in β-keratin composite was analyzed. Cutting tests on the samples of keratin were carried out. The molecular structures of α- and β-keratin were compared. Despite the differences in the molecular structures of the two types of keratins, the toughness of the two appeared to be quite similar. The presence of mult...
Article
A series of three-point bend tests using single edge notched testpieces of pure polycrystalline ice have been performed at three different temperatures (–20C, –30C and –40C). The displacement rate was varied from 1 mm/min to 100 mm/min, producing the crack tip strain rates from about 10–3 to 10–1 s–1. The results show that (a) the fracture toughnes...
Article
Measurement or prediction of the mechanical and fracture properties of foods is very important in the design, operation and optimization of processes, as well as for the control of quality of food products. This paper describes the measurement of yield stress of frozen sucrose solutions under indentation tests using a spherical indenter. Effects of...
Chapter
Active polymer gels have been around now for nearly thirty years [1–2]. Their unique swelling and de-swelling characteristics in the present of solvents, combined with the possibility of triggering the volumetric expansion or contraction by a number of physical and chemical means, make them particularly interesting for actuation. Changes in tempera...
Article
The adhesive fracture energy (fracture toughness) of tapes during globally elastic unpeeling is often calculated from the relation “”. We show that while this expression is correct for elastic peeling from rigid substrates, it gives misleading results when peeling from reversible flexible substrates. A two-dimensional analysis is presented for peel...
Article
Full-text available
Mechanical effects of turgor pressure on cell walls were simulated by deforming cell wall analogues based on Acetobacter xylinus cellulose under equi-biaxial tension. This experimental set-up, with associated modelling, allowed quantitative information to be obtained on cellulose alone and in composites with pectin and/or xyloglucan. Cellulose was...
Article
Full-text available
The functional design of the campaniform sensillum was modelled as a hole in a plate using two- and three-dimensional finite-element modelling. Different shapes of opening in a fibrous composite plate amplify differently the global strains imposed on the plate, and different configurations of reinforcement also have an effect. In this paper, the ma...
Article
Full-text available
A clear relationship has been established between the impact resistance and density of softwoods. However, there are hardwood species that have the same density but very different impact resistance. Softwoods are largely composed of tracheid cells (30-50 microm across); hardwoods have smaller fibre cells and also contain vessels (50-500 microm acro...
Article
Full-text available
A simple relationship is obtained between the external force F and the fracture toughness R for thin sheets in steady state elastoplastic combined tearing and peeling along se similar paths. The relationship depends only on the material properties (E, sigma (y), and alpha for an elastoplastic material with linear hardening) and strip cross section...
Article
Precise measurements of the deformation and fracture behaviour of food can be difficult because of problems associated with the produce, for example, sample preparation, gripping, size and geometry. The aim of this study was to characterise fruits and vegetables in terms of fracture properties using an established engineering test method and geomet...
Article
A treatment is described that enables epoxy resin to penetrate into the cell walls of plant fibres. This ensures a very good interface in the cured composites, mimicking the way that interfaces are formed in animal and plant materials. The treatment involves swelling the plant cell walls with urea solution, washing out the excess urea and then repl...
Article
The design and prototype manufacture of a controlled-stiffness composite femoral prosthesis is described. The prosthesis is composed of a cobalt-chrome core surrounded by a flexible composite outer layer. By varying the composite layer thickness it was possible to control the prosthesis stiffness. The new design was critically assessed by means of...
Article
Cross-ply GFRP circular plates have been impacted repeatedly at increasing input energies. The global bending stiffness of each plate was measured before and after each impact through quasi-static bending tests. The effects of local thickening as well as matrix cracking and delamination on global bending stiffness have been discussed. Approximate a...
Article
High volume fraction hemp and flax fibre composites were manufactured using low viscosity epoxy and phenolic resins. Using 80% volume fraction of flax fibres in epoxy resin, composites with a mean stiffness of 26 GPa and a mean strength of 378 MPa were produced. By reducing processing damage of the plant fibres mechanical properties could be increa...
Article
Morphological measurements of penguin feathers are used to construct a thermal model of heat transfer through the coat. Assuming uniform distribution of the feathers and their associated afterfeathers, it is possible to model heat transfer through the coat of the penguin using standard theory. It is shown that convection does not occur in the coat...
Article
Free vibration tests have been conducted to study the effect of low-velocity impact induced damage consisting of interlaminar delamination accompanied by matrix cracking on the natural frequencies of thin composite laminated circular plates. Local thickening has been identified, for the first time, as one of the important factors that influence the...
Article
Biaxial loading of pre-cracked cruciform testpieces has been preformed in a novel rig attached to a uniaxial testing machine. Fracture toughness R or c of the ductile acrylonitride butadiene styrene (ABS) and polyvinyl chloride (PVC) determined by the Cotterell–Mai method is dependent on remote biaxiality. Least toughness is shown for equibiaxial t...
Article
Previous studies have suggested that a controlled stiffness prosthesis is required to address the conflicting requirements of minimizing stress shielding and micromotion. The design for a controlled stiffness prosthesis is proposed and a preliminary analytical investigation performed to assess its predicted performance before fabrication of a proto...
Article
Simultaneous tearing and peeling of multiple strips is theoretically investigated using the large deflection theory of cantilevers made of elastoplastic material with linear strain hardening. The relationship between the fracture toughness and the curvature at the fracture propagation front is obtained for general cases. It is shown that for the mo...
Article
Experiments have been carried out to assess the fracture behaviour of potato tuber parenchyma tissue from two different varieties (cvs. King Edward and Record) in three different turgor states (turgid, fresh and flaccid). Methods included wedge-penetration fracture tests, razor-blade cutting tests, ball indentation tests and compression tests. Turg...
Article
Biological structures have evolved to fit their purpose and a discussion is given of the materials and engineering reasons for their success. The contrast is made between traditional engineering's extraction of maximum benefit from choice of materials and Nature's extraction of maximum benefit from structural shapes made of indifferent materials. T...
Article
The interface structure of poly(ether-ether-ketone) (PEEK)-carbon fibre composite and the crystal texture of PEEK matrix have been studied by scanning electron microscopy (SEM) after the samples were properly etched by argon plasma. We find that most of the PEEK'S crystals are induced by nucleating carbon fibre and then they developed the transcrys...
Chapter
A large part of the effort of the food industry is spent in attempting to understand the limitations of the type of food that animals can eat. An understanding of the factors that influence feeding behaviour can then be used to produce foodstuffs that are more attractive to the animal in question, whether it be man, cattle, dogs or cats. This book...
Article
The fracture properties of foods are relevant to texture but can be difficult to measure because of limitations of size or shape. Many established engineering tests for the measurement of crack growth and unstable propagation of cracks require specific test geometries, sizes and compliances of the specimen. With food materials this is rarely possib...
Article
The fracture toughness and dynamic mechanical moduli of frozen beef M. semitendinosus were investigated at various sub-zero temperatures using several different test geometries. Traditional fracture mechanics methods were considered inapplicable to frozen meat, since considerable plastic flow occurs in addition to elastic deformation and fracture....
Article
Many natural collagen containing materials are highly extensible composites and their mechanical behaviour will depend on the amount of collagen fibres present, the mechanical properties of the fibres and their distribution and orientation. A characteristic feature of these materials is that the fibrous collagen network can change orientation durin...
Article
Wood is a complex composite material that possesses an excellent combination of mechanical properties. In particular the toughness, or work of fracture, is very high, reaching a value in excess of 1.0 × 104 J/m2, which, mass for mass, is roughly equal to the toughness of steel and higher than that of artificial composites. The high work of fracture...
Article
THE work of fracture (that is, the energy needed in order to form a fracture surface roughly at right angles to the grain direction) is, for timber, exceptionally high in relation to other mechanical properties and density. It compares well, on a weight basis, with that of ductile metals. Our tests on air dry (12% moisture content) pitchpine (Pseud...
Article
Full-text available
SOMMARIO La vibrometria Laser, basata sull'effetto Doppler, consente di rilevare spostamenti d'ordine inferiore al nanometro. Questo la rende un metodo non distruttivo versatile per un gran numero d'applicazioni su ogni tipo di materiale, in particolare per il controllo del danneggiamento e dell'effetto delle alterazioni strutturali. La presente me...
Article
Full-text available
This is a preliminary study for microscopic lens thermography observations on a film-like and non-blackbody material. With this aim, a number of features present on the surface of a cardboard for storage boxes (grammage 300 g/m²) are observed using a Flir SC 3000 thermal imager microscopic lens with 26 mm fixed focal distance. Comments on quality o...
Article
Full-text available
Electro Active Polymers (EAPs) respond to an applied electrical potential with displacement. This permits their use for electrically-driven actuation mechanisms and in reverse as strain sensors. EAPs are currently the most promising class of materials for 'artificial muscles', as they are light-weight with high compliance, have high active strains...
Article
Full-text available
This work is aimed at presenting a simple and innovative method for the measurement of surface void content on balsa wood samples, slightly heated using microwaves, applying active IR thermography with a fixed focus microscopy lens. This method involves basic image thresholding to visualise voids, and appears to offer good results, when compared wi...

Network

Cited By