Ultrasonic sensors and techniques for motion tracking and characterization of biological soft tissues

各种慢性疾病，如影响血液循环的关节硬化症和影响老年人肌肉骨骼系统的类风湿性关节炎，都会损害他们的体能。一旦出现身体障碍，老年人通常会躺在床上休息，并需要照顾者的帮助来维持他们的日常活动。此类疾病的早期诊断对于制定旨在阻止疾病进一步发展的适当治疗策略至关重要。生物组织的力学性质为医学诊断提供了重要的重要信息。超声具有无创、无风险(无电离辐射照射)、高帧速率、低成本实时采集图像等优点，已成为一种强有力的诊断工具，并得到了广泛的应用。超声诊断技术不仅可以提供解剖结构的静态图像，还可以提供与身体活动和生理状况相关的内部组织运动的实时动态信息。实时、连续的超声监测有利于在临床设施和实验室之外进行诊断，不干扰日常生活活动。然而，目前的便携式超声成像系统和超声探头可能不适合在家中进行长时间、连续的监测。因此，膜式柔性和专用超声波传感器有利于提供与人体选定位置的稳定接触，例如颈部、手臂和腿部，这些部位是弯曲的、可变形的和可移动的。人们还希望这种传感器是可穿戴的和紧凑的。这项研究计划将开发一种低成本、轻便、可靠、可批量生产和一次性使用的非侵入性超声可穿戴传感器(WUS)技术，用于自动和连续评估心脏健康监测的动脉功能。利用开发的WUS技术，将建立连续监测心血管功能的临床应用，如血压波形和动脉僵硬。传感器的一次性对于接触人体的医疗设备是可取的，因为它在使用后不需要消毒或灭菌。开发的WUS技术将包括先进的信号处理算法，可以自动检测动脉区域并实时估计动脉直径的变化。开发的WUS技术将允许在医院、诊所和实验室之外监测患者的心血管健康状况。此外，人们将能够佩戴高性价比的超声波传感器，持续监测他们的健康状况。

Various chronic ailments such as arthrosclerosis affecting blood circulation and rheumatoid arthritis affecting the musculoskeletal system in elderly people impair their physical ability. Upon onset of a physical disorder elderly people are often placed on bed rest and require assistance from caregivers to maintain their daily activities. Early diagnosis of such ailments is crucial for devising appropriate treatment strategies aimed to impeding further progression of the disease. Mechanical properties of biological tissues contain significant and vital information for medical diagnosis. Ultrasound has been a powerful tool for diagnosis and is widely used since it is noninvasive, risk-free (no ionizing radiation exposure), and capable of capturing images in real-time at a high frame rate and at low-cost. Ultrasonic diagnostic techniques can provide not only static images of anatomical structures but also real-time dynamic information of internal tissue motion associated with physical activities and physiological condition. Real-time and continuous ultrasonic monitoring is beneficial for carrying out diagnosis outside clinical facilities and laboratories, without interfering with daily life activities. However, the current portable ultrasound imaging system and ultrasound probe may not be suitable for a long-time and continuous monitoring at home. Therefore, film-type flexible and dedicated ultrasonic sensors are beneficial for providing stable contact with chosen locations of a human body, such as a neck, arm and leg, which is curved, deformable and movable. It is also desirable that such sensors be wearable and compact. This research program will develop a low-cost, lightweight, reliable, mass-producible and disposable non-invasive ultrasonic wearable sensor (WUS) technology for automatic and continuous assessment of arterial functions for cardiac health monitoring. Using the developed WUS technology, a clinical application for continuous monitoring of cardiovascular functions such as blood pressure waveforms and artery stiffness will be established. Disposability of the sensor is desirable for a medical device that contacts a human body since it does not require disinfection or sterilization after its usage. The developed WUS technology will include advanced signal processing algorithms that can automatically detect arterial regions and estimate arterial diameter changes in real-time. The developed WUS technology will allow monitoring of cardiovascular health conditions of patients outside hospitals, clinics, and laboratories. Furthermore, people will be able to wear cost-effective ultrasonic sensors that will continuously monitor their health conditions.