Sustainable Digital Fabrication of Low Energy Passive Wireless Sensors

This project concerns new ways of fabricating exciting new wireless sensing technologies. Our Digital Future and The Internet of Things have application in intelligent buildings, homeland security, oil and gas industries, assisted living and healthcare, agriculture, transport and environmental monitoring. Research is already being carried out in Intelligent packaging to indicate wirelessly when food is deteriorating; tamper-proof light-sensing tags; labels that detect explosives; or sweat and pH sensors for biomedical applications that assess how a recent operation is healing. The sensors in these new technologies must be small, thin and very cheap. Also, not needing a battery will reduce cost and the need for chemicals which are bad for the environment.

In this project we will investigate sensing technologies two areas of global significance: (i) Food Security and (ii) National Security/Bio-sensing.

In the first application, Food Security, (i.e. the stable and sustainable provision of sufficient food to the populations of developed and developing countries) will become critically important with expanding global populations and increasing food prices. Roughly 30-40% of all food is currently wasted with an increasing need for postharvest storage technologies effecting small scale traders, distributers, vendors and consumers. Reducing waste in developed countries is particularly challenging and is linked to cultural attitudes and lifestyle. In the UK the following sectors account for various proportions total waste: Farms: 15%, Transport/processing: 25%, Retail: 10%, Food service: 15%, Home & municipal: 35%. Smart packaging which detects food breakdown from farm pack house to consumer storage can significantly impact on this wastage at all parts in the chain though technologies are sought that will minimise the cost and infrastructure impact on suppliers and customers.

The second application is for bodyworn and bio-sensing where body- and skin-mounted wireless sensors have significant potential for monitoring of vital signs in security, emergency services, and medical/health use. However, there is a continuing drive for organisations such as the police to adopt existing and modified off-the-shelf technologies rather than developing infrastructure from scratch. For instance, smart phones are now permitted for certain uses by the armed forces and the MoD Blackberry has been adopted for classified email access. The technologies proposed here for rapid development and manufacture do not require unique new-builds as they enable add-ons to NFC RFID enabled smart phones and commercial RFID readers.

In all applications, battery-free wireless sensor fabrication has significant benefits for replacement cost and environmental issues such as extraction of materials and disposal at end of life. Also, barriers exist to national and global adoption of this emerging sensing area because many current technologies are adaptations of conventional wireless, power storage and sensing solutions. We propose a new approach where digital fabrication processes are applied to novel passive wireless sensing to lead to game changing impact, reduced costs and wastage, and to overcome the barriers to large scale adoption.

The digital fabrication to be used is Inkjet printing, and we will not only print stretching and bending metal tracks onto elastic polymer substrates, but also modify the substrates to make them sensitive to certain chemicals. Finally, we will also explore how to print the polymer substrate itself, enabling the entire tag metal antenna and sensing base to be fabricated by inkjet.

In order to maximise the impact of our research we will use existing strong communication and engagement channels with key stakeholders. It is routine for us to invite interested parties to regular project progress meetings and for us to give invited talks. One example is Kent's attendance at the DSTL Antenna Steering Group were our research was presented to a forum comprising members from DSLT, MoD, HMGCC and GCHQ. The Wireless Friendly Building Forum is again a means for communicating the results of our work which uses its website and attendance at special stakeholder events to from a platform for publicising the progress of this project. Additionally, Batchelor's school at Kent uses new social media effectively and previous approaches from the wider media have resulted from our tweets.

OMIC's membership and collaboration with the Electronic, Sensors and Photonics KTN as well as the Organic Electronics association will communicate progress within the programme and identify potential collaborators. Experience and contacts made within the Northernway Printed Electronics Supply Chain Project 2009-2011 have facilitated engagement and visibility within the UK the print community which have been invaluable in project exploitation. Through Yeates' role as on the organising committee of the Non Impact Printing conference in the US we will enable visibility to the most recent advances annually to a global scientific and industrial community. Public engagement will be actively encouraged, the visual and tactile nature of the technology making it widely accessible through such forums as the Royal Society Summer Science exhibition and Manchester Science week.

We are working with supporters including soft fruit suppliers, packaging producers and defence engineers and we have prepared this proposal in association with them. They have been actively advising and steering us towards an end user perspective and will be invited to attend at least one formal research meeting a year as an advisory panel. It is intended they will inform and guide us throughout the project as well as indicating necessary follow-on work such as necessary clinical trials or the practicalities of transfer and uptake. For instance, Peter Vinson is a member of Berryworld Ltd. and will provide a conduit for our outputs to be considered by fruit distributers and correctly trialled for eventual uptake. For instance, he has identified a barrier to adoption will be the cost and complexity of tag placement equipment as this must be borne by the suppliers. Our discussions with Crown Packaging plc in Oxfordshire have identified the need for demonstrators of novel technologies to interest clients. Additionally Dr Jonathan Miller of DSTL, Fort Halstead, is informing us about the relevance of rapid design-to-fabrication cycles for future wearable technologies working in association with off-the-shelf infrastructures. This existing and on-going experience base will inform and steer our pathways to impact.

We will create demonstrators and resource a presence at a national industrial/public show such as Pro2Pac 2015 at the London ExCeL and a European industrial conference such as an IDTechEx Wireless Sensor Network event. There would also be visits to companies for dissemination and potential print trials as well as attendance at industrial conferences and the regular Wireless Friendly Building Forum meetings.