Passively Powered Non-invasive Human Body Sensing on Bio-Degradable Conformal Substrates

在过去的十年中，优秀的非侵入式传感平台已经可以用于捕获实时健康和生活方式数据，fitbit和Apple Watch就是众所周知的例子。然而，目前的“可穿戴”传感器都有很大的局限性：它们通过绑带和类似的东西连接到身体上，不能长时间保持良好的连接；它们的功耗很高，这意味着设备最多每隔几天就要关机充电一次；它们造成了大量的电子垃圾。因此，他们远没有实现自己的真正潜力。这一挑战得到了EPSRC的认可，“传感和分析的颠覆性技术”成为2015年医疗技术战略的核心部分。我们建议通过推进新型材料制造方法来解决这一挑战，以实现下一代“共形”传感器节点。这将成为一个颠覆性的下一代传感器平台，用于长期监测许多身体参数（运动，电生理和温度数据），这与当前的生物传感方法非常不同。我们的新型制造将使传感器能够：-安装在保形基板上，直接附着在皮肤上，无需带，并一次保持接触数天。-使用喷墨打印制造，以减少浪费和响应式制造，可能为每个人量身定制每个传感器。基于石墨烯纳米颗粒的油墨将取代目前的银纳米颗粒油墨，由于石墨烯的惰性性质，银纳米颗粒油墨避免了与银油墨相关的电子垃圾问题。-采用新的油墨和衬底配方，使石墨烯油墨和共形衬底都是“瞬态”的。也就是说，它们工作一段时间，然后自然分解成安全、惰性和易于拆卸的部件，便于使用和处置。-使用在预应力基板上制造的“弹出式”结构实现3D。这将允许“驱动天线”，耦合3D天线的机械和电磁特性，以便使用天线组件同时进行传感和传输，大大减小设备尺寸，因为传统仪器可以移除。-超低功耗，采用新颖的开关策略，允许通过RFID无线链路进行安全的数字传输，而无需专用的高功率模数转换器微芯片。-通过设计减小尺寸的表皮天线，增加无线供电范围，利用纹身天线中的磁耦合环路，其表面积小于当前方法的3倍，减少了数字制造中墨水的使用。-对运动干扰的鲁棒性进行了优化，允许在现实世界中收集高质量的信号。-适用于关键元件的卷对卷和/或单张纸印刷的规模化生产，集成取放功能。-集成到最初的完整系统演示中，将向我们的合作伙伴展示，包括老年人和儿童长期使用传感器节点。总的来说，这些都代表了超越目前可用的“可穿戴”设备的一个步骤。我们的新传感器将是可定制的无电池RFID标签，它可以在距离供电读取器一米多的地方工作，一次可以连接许多天，并且具有由制造的瞬态特性设定的可控制寿命。在这个早期阶段，我们不建议针对任何一个临床应用领域，而是为保形身体传感器节点开发下一代技术，收集与许多疾病领域相关的纵向信息。我们将与合作伙伴一起，通过各种途径开展影响活动，最大限度地提高在医疗保健场景中接触相关最终用户的可能性。

Over the last decade excellent non-invasive sensing platforms have become available for capturing real-time health and lifestyle data, with the fitbit and Apple Watch being well known examples. However, current 'wearable' sensors all have major limitations: they connect to the body using straps and similar which do not maintain a good connection over long time periods; they have high power consumptions meaning the device must be taken off and recharged, at best, every couple of days; they contribute a significant amount to electronic waste. They are thus far from realising their true potential. This challenge is recognised by the EPSRC, with 'Disruptive technologies for sensing & analysis' being a core part of the 2015 Healthcare Technologies strategy. We propose to tackle this challenge by advancing novel material manufacturing approaches to realise next generation 'conformal' sensor nodes. This will make a disruptive next generation sensor platform for the very long term monitoring of a number of body parameters (motion, electrophysiological and temperature data) which is very different to current bio-sensing approaches. Our novel manufacturing will enable sensors which are: - Mounted on a conformal substrate, attaching directly to the skin without a strap, and maintaining contact for several days at a time.- Manufactured using inkjet printing to allow minimal waste and responsive manufacturing, potentially tailoring each sensor to each person. Graphene nanoparticle based inks will replace current silver nanoparticle inks which, due to the inert nature of graphene, avoids the electronic waste issues associated with silver inks. - Tailored with new ink and substrate formulations so that both the graphene ink and conformal substrate are 'transient'. That is, they work for a period of time and then naturally decompose into safe, inert and easily removed components, enabling easy use and disposal.- 3D in nature by using 'popup' structures manufactured on pre-stressed substrates. This will allow 'actuated antennas', coupling the mechanical and electromagnetic properties of a 3D antenna in order to allow simultaneous sensing and transmission using the antenna component, significantly reducing the device size as conventional instrumentation can be removed. - Ultra low power using a novel switching strategy to allow secure digital transmission over an RFID wireless link without the need for a dedicated, high power, analogue-to-digital converter microchip. - Increased in wireless powering range, by devising reduced size epidermal antennas that exploit magnetically coupled loops in tattoo antennas with under 3 times the surface area of current approaches, reducing ink use for digital fabrication.- Optimized for robustness to motion interference, allowing the collection of high quality signals in real-world, out-of-the-lab situations. - Suitable for scale-up manufacturing with roll-to-roll and/or sheet fed printing of key elements, integrating with pick and place capabilities. - Integrated into initial complete system demonstrators which will be showcased to our partners, covering the use of long term sensor nodes with people who are elderly and with children. Collectively these represent a step change beyond 'wearable' devices available today. Our new sensors will be customisable battery-less RFID tags that can operate more than a metre from a powered reader, stay attached for many days at a time, and with a controlled lifetime set by the transient nature of the manufacturing. At this early stage we do not propose to target any one clinical application area, but rather to make the next generation of technologies for conformal on-body sensor nodes that collect longitudinal information relevant to a number of disease areas. We will work with our partners through pathways to impact activities to maximise the possibility of exposure to relevant end users in healthcare scenarios.