Augmented paper applications: Initial user tests of a wireless pattern reader

A handheld pattern reader has been developed to read low visibility conductive patterns on paper. The patterns are formed by masking conductive paper with a non-conductive, printed lacquer. The reader was developed as part of an EU-funded project investigating methods of augmenting paper. Data read from the patterns was used to trigger events in the digital domain. Usability tests were undertaken to investigate the performance of the prototype. Results showed that at this stage of development there was significant variation in performance of the prototype from user to user. Further work is being undertaken to determine the causes of this variability

A time-strain monitoring system fabricated via offset lithographic printing

This paper reports progress in the development of strain sensors fabricated using the Conductive Lithographic Film (CLF) printing process. Strain sensitive structures printed via an unmodified offset lithographic printing press using a silver loaded conductive ink have been deposited concurrently with circuit interconnect, to form an electronic smart packaging system. A system populated with SMT components has proven successful in interpreting and logging deformation incidences subjected to a package during testing. It is proposed that with further development such a system could be printed in sync with packaging graphics using a single printing process to form an integrated time – strain monitoring system

Fabrication and characterization of smart fabric using energy storage fibres

Fibre supercapacitors were designed and manufactured using a dip-coating method. Their electrochemical properties were characterized using a VersaSTAT 3 workstation. Chinese ink with a fine dispersion of carbon and binder was coated as the electrode material. The specific capacitance per unit length of a copper fibre supercapacitor with the length of 41 cm reached 34.5 mF/cm. When this fibre supercapacitor was bent on rods with a diameter of 10.5 cm, the specific capacitance per length was 93% of the original value (without bending). It showed that these fibre supercapacitors have good flexibility and energy storage capacity. Furthermore, the fibre supercapacitor in the fabric showed the same capacitance before and after weaving.The European Union Seventh Framework Programme (FP7/2007–2013) under grant agreement no. [281063]

A study of the electrochemical performance of strip supercapacitors under bending conditions

© 2016 The Authors. In recent years, much effort has been spent developing thin, lightweight and flexible energy storage devices to meet the various requirements of modern smart electronics. In this work, thin strip supercapacitors were successfully developed using activated carbon as the active electrode material. The electrochemical performance of these strip supercapacitors has been studied under mechanical bending conditions. The results indicate that the strip supercapacitor was functional under bending conditions between the bending angles of 30° to 150°. The capacitance of the sample was still about 70% of the original capacitance at different bending angles. This suggests the strip supercapacitor developed has a reasonable flexibility. Simulation model of equivalent circuit was established to analyze the charge transfer resistance (CTR) and equivalent series resistance (ESR) results in electrochemical impedance spectroscopy (EIS) testing. The correlation between the capacitance and the resistance of the strip supercapacitor under bending conditions was investigated and obtained.The European Union Seventh Framework Programme (FP7/2007-2013) under grant agreement no. 28106

Improving the efficiency and accuracy of nocturnal bird Surveys through equipment selection and partial automation

Birds are a key environmental asset and this is recognised through comprehensive legislation and policy ensuring their protection and conservation. Many species are active at night and surveys are required to understand the implications of proposed developments such as towers and reduce possible conflicts with these structures. Night vision devices are commonly used in nocturnal surveys, either to scope an area for bird numbers and activity, or in remotely sensing an area to determine potential risk. This thesis explores some practical and theoretical approaches that can improve the accuracy, confidence and efficiency of nocturnal bird surveillance. As image intensifiers and thermal imagers have operational differences, each device has associated strengths and limitations. Empirical work established that image intensifiers are best used for species identification of birds against the ground or vegetation. Thermal imagers perform best in detection tasks and monitoring bird airspace usage. The typically used approach of viewing bird survey video from remote sensing in its entirety is a slow, inaccurate and inefficient approach. Accuracy can be significantly improved by viewing the survey video at half the playback speed. Motion detection efficiency and accuracy can be greatly improved through the use of adaptive background subtraction and cumulative image differencing. An experienced ornithologist uses bird flight style and wing oscillations to identify bird species. Changes in wing oscillations can be represented in a single inter-frame similarity matrix through area-based differencing. Bird species classification can then be automated using singular value decomposition to reduce the matrices to one-dimensional vectors for training a feed-forward neural network.EThOS - Electronic Theses Online ServiceGBUnited Kingdo

Lithographically printed voltaic cells – a feasibility study

It has been shown that circuit interconnects and various passive components can be fabricated on a variety of flexible substrates using the offset lithographic process. This paper reports on a feasibility study investigating the manufacture of voltaic cells deposited via offset lithography. The Leclanche´ cell, an established battery chemistry, was chosen as an appropriate technology for adaptation to the offset lithographic process. Development of inks with appropriate rheological properties for lithographic printing was undertaken. Zinc and carbon electrodes were fabricated with silver-based current collectors. Electrolyte composition was investigated along with separator materials. Zinc and carbon-based inks have been produced which result in deposited material appropriate for use as electrodes. A separator material soaked in electrolyte has been combined with these electrode structures and an MnO2 paste to form a voltaic cell. A printed battery, made up of these voltaic cells, with a capacity greater than 8 mAh at 6 V has been produced. The fabrication of voltaic cells via offset lithography facilitates the production of electronic systems with power sources provided by the same printing process. This paper provides information of interest to all those involved in the developing industry of printed and flexible electronics

Development and characterisation of lithographically printed voltaic cells

This paper reports progress in thefabrication ofvoltaic cells and batteries via offset lithographic printing. Successful design and manufacture oflithographically printed voltaic cells wouldfacilitate the integration of printedpassive components, interconnects and display elements for disposable electronics in low-volume, low weight circuits and systems. The Conductive Lithographic Film (CLF) printing process was developed by Brunel University to fabricate circuit interconnect and various passive components at high speed and low cost. Afeasibility study, investigatingprinted cells based on Zinc-Carbon electrochemistry, is described. This has resulted in the production ofa printed battery able to power a microcontroller-driven LED display system for more than three hours. Further work seeks to improve cell capacity, address manufacturing process issues, and characterise the structures in more detail

Experimental design to optimise electrical performance of strip supercapacitors

Strip shaped electric double-layer supercapacitors (EDLCs) using activated carbon as the electrode material have been successfully fabricated and optimised. Their electrochemical characteristics were studied using a VersaSTAT 3 electrochemical workstation. The experimental design software, JMP™, was used to optimise the main parameters of supercapacitors in order to maximise the electrical performance. Simultaneously, the relationship between the electrical performance and the key manufacturing factors of the EDLCs, including the binder content, the electrolyte concentration and the thickness of electrode materials was studied and discussed

Examination of silver-graphite lithographically printed resistive strain sensors

This paper reports the design and manufacture of three differing types of resistive strain sensitive structures fabricated using the Conductive Lithographic Film (CLF) printing process. The structures, utilising two inks prepared with silver and graphite particulates as the conductive phase, have been analysed to determine electrical and mechanical properties with respect to strain, temperature and humidity when deposited on four alternative substrate materials (GlossArt, PolyArt, Teslin and Melinex)

Electroluminescent light sources via soft lithography

Microcontact printing is a process used to print high-resolution protein arrays for biosensors. The paper aims to investigate using these techniques to print electrically conductive fine line structures for electroluminescent (E/L) light sources. The viability of using microcontact printing as a process for electronics fabrication is investigated. Polydimethylsiloxane stamps inked with alkanethiol compounds form self-assembled monolayers on substrate surfaces, acting as the resist to subsequent etching processes. The printed lines are characterized with regard to their performance as high-electric field generators in electroluminescent displays. It has been demonstrated that microcontact printing is a cheap, repeatable process for fabricating electronic devices. The results demonstrate the viability of the process to fabricate electric field generator structures for E/L light sources with reduced driving voltages. The paper demonstrates that microcontact printing can produce electrically conductive fine-line structures with high resolution, confirming its viability in printed electronics manufacture