Design of Motion-Artifact Robust Electronic Tattoos and Software Reconfiguration Methodologies for Bio-impedance Sensing

电子纹身是一种超薄、超软的传感器和电子设备，可以像临时转移纹身一样非侵入性地附着在人体皮肤上。与最先进的可穿戴电子产品相比，电子纹身具有几个特殊的特点。首先，它们与皮肤保持一致，并与人体紧密接触，从而实现可靠的信号测量。其次，它们可以让皮肤呼吸，消除传统贴片的不利影响。最后，它们不限制自然的皮肤运动，因此为用户提供了高度的舒适性。换句话说，用户可能会“戴上它，然后忘记它”。电子纹身将为影响国民健康的下一代无处不在、不引人注目和具有成本效益的健康和健康监测提供新的机会，将个人需要的个性化护理带到家里。战略教育和外展努力的重点是通过为期一年的本科生研究经验扩大未被充分代表的群体在科学和工程领域的参与，并与德克萨斯农工大学EnMed项目和德克萨斯大学-奥斯汀新生NSF工程研究中心合作，加强研究生院的准备工作。新兴的生物阻抗传感提供了新的范式来捕捉人体手腕周围的许多重要的生理信号，包括心率、呼吸频率和血压。手腕作为人体最有活力的部位，处于不断的运动状态。生物阻抗传感的主要挑战是运动伪影的负面影响，运动伪影会破坏数据，降低信号保真度，并阻碍足够自信的决策。我们的项目利用超薄和超软的电子纹身在手腕上进行生物阻抗传感，因为电子纹身使电极和人类皮肤能够实现最亲密但非侵入性的耦合，即使在严重皮肤变形的情况下也是如此。我们的项目还探索了软件重新配置方法和机器学习技术，以进一步应对挑战。具体来说，我们研究了：1)首次设计和开发了一系列亚微米厚、皮肤一致的石墨烯电极纹身，以及2)新的重构技术，将消除或减少与运动伪影相关的噪声，并提高信号保真度。

Electronic-tattoos (e-tattoos) are ultra-thin, ultra-soft sensors and electronics that can noninvasively adhere to human skin like a temporary transfer tattoo. Compared to the state-of-the-art wearable electronics, e-tattoos offer several exceptional characteristics. First, they conform to the skin and create a tight contact with the human body enabling robust signal measurements. Second, they may allow the skin to breathe eliminating the adverse effect of traditional adhesive patches. Lastly, they do not constrain natural skin motion hence present high degrees of comfort for the user. In other words, the user may "put it on and forget about it". E-tattoos are poised to enable new opportunities for the next generation of ubiquitous, unobtrusive and cost-effective health and wellness monitoring impacting the national health, bringing personalized care the individuals need to their homes. A strategic education and outreach effort focuses on broadening the participation of underrepresented groups in science and engineering via a year-long undergraduate research experience with enhanced graduate school preparation in partnership with Texas A & M University EnMed program and University of Texas-Austin NASCENT NSF Engineering Research Center. Emerging bio-impedance sensing offers new paradigms to capture a number of important physiological signals including heart rate, respiration rate and blood pressure, all around the human wrist. As the most dynamic body part, the wrist is under constant movement. The major challenge in bio-impedance sensing is the negative effects of motion artifacts that corrupt the data, degrade the signal fidelity, and prevent decision making with sufficient confidence. Our project leverages ultra-thin and ultra-soft e-tattoos for bio-impedance sensing on the wrist because e-tattoos enable the most intimate but noninvasive coupling for the electrodes and the human skin, even under severe skin deformation. Our project also explores software reconfiguration methodologies and machine learning techniques to further address the challenges. In particular, we investigate: 1) design and development of an array of submicron-thick, skin-conformable graphene electrode tattoos for the first time, and 2) novel reconfiguration techniques that would eliminate or reduce the noise associated with motion artifacts and enhance the signal fidelity.