Biocompatible Soft Fluidic Strain and Force Sensors for Wearable Devices

Fluidic soft sensors have been widely used in wearable devices for human motion capturing. However, thus far, the biocompatibility of the conductive liquid, the linearity of the sensing signal, and the hysteresis between the loading and release processes have limited the sensing quality as well as the applications of these sensors. In this paper, silicone based strain and force sensors composed of a novel biocompatible conductive liquid (potassium iodide and glycerol solution) are introduced. The strain sensors exhibit negligible hysteresis up to 5 Hz, with a gauge factor of 2.2 at 1 Hz. The force sensors feature a novel multifunctional layered structure, with microcylinder‐filled channels to achieve high linearity, low hysteresis (5.3% hysteresis at 1 Hz), and good sensitivity (100% resistance increase at a 5 N load). The sensors' gauge factors are stable at various temperatures and humidity levels. These biocompatible, low hysteresis, and high linearity sensors are promising for safe and reliable diagnostic devices, wearable motion capture, and compliant human–computer interfaces.     

Biocompatible Blends of an Intrinsically Conducting Polymer as Stretchable Strain Sensors for Real-Time Monitoring of Starch-Based Food Processing

Because stretchable strain sensors that have a resistance or capacitance sensitive to strain can sense skin deformation during physical movement, they have been extensively studied as wearable devices for healthcare monitoring. In principle, they can be used to monitor starch-based food processing in real time, since starch-based food can have remarkable volume change during processing. Monitoring starch-based food processing in real time can help achieve high quality and high productivity while reducing energy consumption. Nevertheless, there is no such report in the literature. Here, a blend of starch and a biocompatible intrinsically conducting polymer, poly(3,4-ethylenedioxythiophene): polystyrenesulfonate (PEDOT:PSS), is reported as a stretchable strain sensor to monitor starch-based food processing including fermentation, steaming, storage, and refreshing in a real-time manner. The resistance of the blends increases during the food volume expansion mainly caused by the fermentation, steaming, and refreshing, and it decreases as a result of the food volume shrinkage during cooling or storage. The signals can be thus used to optimize the processing conditions and control the food quality. This technology can be easily combined with the Internet of Things.     

Colorimetric Nanofibers as Optical Sensors

Sensors play a major role in many applications today, ranging from biomedicine to safety equipment, where they detect and warn us about changes in the environment. Nanofibers, characterized by high porosity, flexibility, and a large specific surface area, are the ideal material for ultrasensitive, fast‐responding, and user‐friendly sensor design. Indeed, a large specific surface area increases the sensitivity and response time of the sensor as the contact area with the analyte is enlarged. Thanks to the flexibility of membranes, nanofibrous sensors cannot only be applied in high‐end analyte detection, but also in personal, daily use. Many different nanofibrous sensors have already been designed; albeit, the most straightforward and easiest‐to‐interpret sensor response is a visual change in color, which is of particular interest in the case of warning signals. Recently, many researchers have focused on the design of so‐called colorimetric nanofibers, which typically involve the incorporation of a colorimetric functionality into the nanofibrous matrix. Many different strategies have been used and explored for colorimetric nanofibrous sensor design, which are outlined in this feature article. The many examples and applications demonstrate the value of colorimetric nanofibers for advanced optical sensor design, and could provide directions for future research in this area.     

光纤电流传感器研究新进展

介绍了全光纤电流传感器自１９９４ 年以来在光纤处理技术、新光路设计、新材料光纤、新结构光纤及对系统性能的专项研究方面取得的新进展。     

CMOS Differential and Absolute Thermal Sensors

This paper treats the test of CMOS digital ICs by using the thermal mapping of the silicon surface as a test observable. Two different temperature-sensing strategies are presented. The novel sensors developed are an on-chip CMOS Differential Temperature (DT) sensor and a Proportional to Absolute Temperature (PTAT) sensor. The sensors have been implemented in a standard .18 m CMOS technology.     

混合型光纤传感器

混合型光纤传感器综合了传统传感器已经验证的传感可靠性以及光纤数据传输的优点,易于实现传统传感器的光纤遥感、遥测。本文评述的混合光纤传感器类型范围涉及;电源驱动,光源驱动、硅微技术,特别应值得注意的是利用光纤通信网络传输传感数据的途径。     

国外声表面波传感器开发近况

以声表面波气体、温度和压力传感器为例，介绍了国外声表面波传感器的开发近况。指出了开发的重点、难点及今后的发展方向。     

干涉技术在光纤传感器设计中的应用

介绍了干涉型光纤传感器的基本原理，结合实例阐述了各种干涉型光纤传感器的设计方法与实现技术，讨论了光纤传感器所用光源的选择，举例说明了干涉仪在大规模、长距离传感系统中的应用方法，并展望了这类光纤传感器的发展前景。     

Rational Design of All Resistive Multifunctional Sensors with Stimulus Discriminability

A rational approach is proposed to design soft multifunctional sensors capable of detection and discrimination of different physical stimuli. Herein, a flexible multifunctional sensor concurrently detecting and distinguishing minute temperature and pressure stimuli in real time is developed using electrospun carbon nanofiber (CNF) films as the sole sensing material and electrical resistance as the only output signal. The stimuli sensitivity and discriminability are coordinated by tailoring the atomic- and device-level structures of CNF films to deliver outstanding pressure and temperature sensitivities of ? 0.96 kPa^?1 and ? 2.44%  ° C^?1, respectively, enabling mutually exclusive sensing performance without signal cross-interference. The CNF multifunctional sensor is considered the first of its kind to accomplish the stimulus discriminability using only the electrical resistance as the output signal, which is most convenient to monitor and process for device applications. As such, it has distinct advantages over other reported sensors in its simple, cost-effective fabrication and readout system. It also possesses other invaluable traits, including good bending stability, fast response time, and long-term durability. Importantly, the ability to simultaneously detect and decouple temperature and pressure stimuli is demonstrated through novel applications as a skin-mountable device and a flexible game controller.     

块状光学材料电流传感器研究新进展

主要介绍了块状光学材料电流传感器研究领域自１９９４年以来在传感头设计方案、理论研究及信号处理方案等方面的新进展。     

Biodegradable and Highly Deformable Temperature Sensors for the Internet of Things

Recent advances in biomaterials, thin film processing, and nanofabrication offer the opportunity to design electronics with novel and unique capabilities, including high mechanical stability and biodegradation, which are relevant in medical implants, environmental sensors, and wearable and disposable devices. Combining reliable electrical performance with high mechanical deformation and chemical degradation remains still challenging. This work reports temperature sensors whose material composition enables full biodegradation while the layout and ultrathin format ensure a response time of 10 ms and stable operation demonstrated by a resistance variation of less than 0.7% when the devices are crumpled, folded, and stretched up to 10%. Magnesium microstructures are encapsulated by a compostable‐certified flexible polymer which exhibits small swelling rate and a Young's modulus of about 500 MPa which approximates that of muscles and cartilage. The extension of the design from a single sensor to an array and its integration onto a fluidic device, made of the same polymer, provides routes for a smart biodegradable system for flow mapping. Proper packaging of the sensors tunes the dissolution dynamics to a few days in water while the connection to a Bluetooth module demonstrates wireless operation with 200 mK resolution prospecting application in food tracking and in medical postsurgery monitoring.     

压力传感器的芯片封装技术

对压力传感器芯片的各种封装技术作了比较和讨论，指出它们的优缺点和适用场合。还对各种封接键合材料的特性作了概括。     

红外热释电传感器的温度稳定性

本文推出红外热释电传感器的响应率与温度的函数式，并提供和分析了实验结果，理论和实验表明，热释电传感器的性能很大程度上取决于其前放级的设计水平。     

基于光纤光栅的分布式传感器

分布式传感器是光纤光栅的重要应用方面之一。本文较全面地介绍光纤光栅分布传感器的各种结构和检测方法，分析讨论了它们的特点和性能。     

新颖有源象素图象传感器的新进展

主要介绍静电感应晶体管、电荷调制器件、体电荷调制器件、基极存储图象传感器、增强ＭＯＳ图象、ＣＭＯＳ等有源象素图象传感器的新进展。     

光纤F-P传感器在用于复合材料检测的实验研究

光纤法珀(F-P)传感器广泛的应用于温度、应变、振动和压力等物理量的测量,由于其体积小、精度高等独特的优点非常适合于埋入复合材料或贴在表面对其进行测量,从而实现对符合材料的损伤诊断．利用光纤F-P传感器对复合材料结构损伤进行了试验研究,并结合有限元软件(ANSYS)对光纤F-P传感器在复合材料中的埋入方式、注意事项以及分布原则等进行了综合分析,初步给出了埋入的原则．