Sensors and Actuators A-physical最新文献_第4页

Room-temperature binder-free aqueous nanoimprint of TiO2 nanogratings for plasmonic broadband photodetectors 用于等离子体宽带光电探测器的TiO2纳米光栅的室温无粘结剂水印迹

IF 4.9 3区工程技术 Q2 ENGINEERING, ELECTRICAL & ELECTRONIC

Sensors and Actuators A-physical

Pub Date : 2025-12-14 DOI: 10.1016/j.sna.2025.117402

Yu-Heng Hung , Jyun-Jie Chen , Da-Rong Wang , Hsiang Chen , Hsin-Ying Lee , Chun-Hung Lin

We demonstrate a room‑temperature, high‑fidelity, binder‑free aqueous nanoimprint process that patterns pre‑crystallized anatase titanium dioxide (TiO₂) nanoparticles into subwavelength gratings without any polymeric or sol-gel precursor matrix. A perfluoropolyether (PFPE) soft mold combined with transient UV‑induced surface energy modulation enables complete cavity filling and preserves line‑edge definition during demolding, providing a low‑shrinkage and scalable alternative to resin‑ or sol–gel‑based nanoimprint. The nanoparticle‑derived TiO₂ gratings furnish broadband photonic scattering and diffraction‑assisted optical path lengthening, while subsequent Au nanoparticle (AuNP) decoration introduces localized surface plasmon resonances and near‑field hotspots that couple to grating modes, jointly intensifying ultraviolet field confinement and extending responsivity into the red and near‑infrared. The AuNP-decorated device achieves a responsivity of 9.24 A/W and a detectivity of 7.83 × 10¹² Jones at 365 nm, along with more than 600-fold enhancement in responsivity at 740 nm compared to the pristine TiO₂ device. This water‑based, additive‑minimal route avoids high‑temperature crystallization, reduces carbon contamination risk, and is compatible with temperature‑sensitive and large‑area substrates. These results establish a manufacturable nanoparticle‑derived photonic–plasmonic platform for high‑performance broadband oxide photodetectors.

我们展示了一种室温、高保真度、无粘合剂的水纳米压印工艺，该工艺将锐钛矿二氧化钛（TiO2）纳米颗粒预结晶成亚波长光栅，没有任何聚合物或溶胶-凝胶前驱体基质。全氟聚醚（PFPE）软模结合瞬态紫外线诱导的表面能调制，可以完成空腔填充，并在脱模过程中保持线边清晰度，提供低收缩和可扩展的树脂或溶胶-凝胶基纳米压印替代方案。纳米粒子衍生的TiO2光栅提供了宽带光子散射和衍射辅助光路延长，而随后的Au纳米粒子（AuNP）装饰引入了局部表面等离子体共振和与光栅模式耦合的近场热点，共同加强了紫外场约束，并将响应性扩展到红色和近红外。经aunp修饰的器件在365 nm处的响应率为9.24 a /W，探测率为7.83 × 1012 Jones，在740 nm处的响应率比原始器件提高了600多倍。这种水基、添加剂最少的路线避免了高温结晶，降低了碳污染风险，并且与温度敏感和大面积基材兼容。这些结果为高性能宽带氧化物光电探测器建立了一个可制造的纳米粒子衍生光子等离子体平台。

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引用次数: 0

An underwater comparison study between cometa inertial measurement units (IMU) & Qualisys motion capture system for lower body kinematics during freediving cometa惯性测量单元（IMU）与Qualisys运动捕捉系统水下自由潜水下体运动学比较研究

IF 4.9 3区工程技术 Q2 ENGINEERING, ELECTRICAL & ELECTRONIC

Sensors and Actuators A-physical

Pub Date : 2025-12-14 DOI: 10.1016/j.sna.2025.117350

Pauline Algourdin , Anthéa Serralheiro , Corentin Travouillon , Felix Lefevbre , Benjamin Ostre , Yoann Joliff

Freediving is an increasingly popular sport but remains under-researched due to its specific constraints. Studying kinematics under ecological conditions could improve performance and reduce injury risks. IMUs make it possible, but their reliability depends on the movement being performed. This study aims to test Cometa IMUs compared to Qualisys cameras for measuring lower body kinematics during a vertical flutter kicking motion. Seventeen participants performed a one-minute vertical flutter kick in water, 21 retro-reflective markers and 7 IMUs attached to their lower body. Cameras and IMUs data were processed using inverse methods with an OpenSim model to extract joint angles and kicking frequency. Absolute and relative errors, Pearson coefficients, ICC and Bland-Altman plots were analyzed. Relative error in frequency was less than 3 % across all angles. Relative errors regarding amplitude were below 30 % in the sagittal plane and up to 98 % in other planes. Pearson coefficients were greater than 0.9 in sagittal plane and between 0.71 and 0.8 for other planes indicating caution for those planes. LOA (Limit Of Agreements) indicated greater variability (mean LOA=17°) and biases (mean=-0.2°) showed IMU value overestimation. Differences across planes can be explained by Euler angle sequence used. Cometa IMUs provide lower-body kinematics in flexion in ecological conditions.

自由潜水是一项越来越受欢迎的运动，但由于其特定的限制，研究仍然不足。研究生态条件下的运动学可以提高运动性能，降低损伤风险。imu使其成为可能，但其可靠性取决于所执行的运动。本研究旨在测试Cometa imu与Qualisys相机在垂直扑动踢腿运动中测量下体运动学的比较。17名参与者在水中进行了一分钟的垂直扑动踢腿，他们的下半身附有21个反射标记和7个imu。使用OpenSim模型对相机和imu数据进行逆方法处理，提取关节角度和踢腿频率。分析绝对误差和相对误差、Pearson系数、ICC和Bland-Altman图。各角度频率相对误差均小于3 %。矢状面相对误差小于30 %，其他面相对误差高达98 %。矢状面的皮尔逊系数大于0.9，其他平面的皮尔逊系数在0.71到0.8之间，表明对这些平面要谨慎。LOA（协议极限）表明较大的可变性（平均LOA=17°），偏倚（平均=-0.2°）表明IMU值高估。平面间的差异可以用欧拉角序列来解释。Cometa imu在生态条件下提供下体屈曲运动学。

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引用次数: 0

Portable SPR sensor with laser interference lithography –Fabricated Ag nanogratings for high-sensitivity biosensing 便携式激光干涉光刻SPR传感器-用于高灵敏度生物传感的银纳米光栅

IF 4.9 3区工程技术 Q2 ENGINEERING, ELECTRICAL & ELECTRONIC

Sensors and Actuators A-physical

Pub Date : 2025-12-13 DOI: 10.1016/j.sna.2025.117399

Shaojun Yu , Kai Cao , Jianjun Cao , Yan Kong , Yuanlin Zheng , Wenjie Wan

Although surface plasmon resonance (SPR) technology has advanced rapidly, many existing SPR sensing platforms still suffer from limitations in portability and cost. To address these challenges, we developed a compact grating-coupled SPR (GC-SPR) sensor that employs laser interference lithography for rapid, large-area, and low-cost fabrication of nanogratings. Silver gratings with periods of 611, 781, and 785 nm were prepared, each exhibiting distinct SPR absorption characteristics. Comparative analysis identified the 781 nm grating as the optimal structure, which was subsequently integrated into a compact, fully self-contained GC-SPR device. The turn-key system, constructed via 3D printing, incorporates a lithium battery, LED light source, polarizer, and fiber-optic spectrometer. Performance evaluation using glucose solutions (0–20 %) demonstrated excellent refractive index sensing, achieving a high sensitivity of 715.5 nm/RIU and a high resolution of 3.91× 10⁻⁵ RIU. Furthermore, biosensing capability was validated by detecting Human IgG with a limit of detection (LOD) of 14.35 nM, with clear resonance wavelength shifts confirming specific molecular binding. These results highlight a cost-effective, miniaturized, and high-performance SPR platform with strong potential for point-of-care diagnostics, environmental monitoring, and food safety applications.

虽然表面等离子体共振（SPR）技术发展迅速，但许多现有的SPR传感平台在便携性和成本方面仍然存在局限性。为了解决这些挑战，我们开发了一种紧凑的光栅耦合SPR （GC-SPR）传感器，该传感器采用激光干涉光刻技术快速，大面积，低成本地制造纳米光栅。制备了周期为611、781和785 nm的银光栅，每个光栅都表现出不同的SPR吸收特性。对比分析确定781 nm光栅为最佳结构，随后将其集成到一个紧凑的、完全独立的GC-SPR装置中。该交钥匙系统通过3D打印构建，集成了锂电池、LED光源、偏振器和光纤光谱仪。使用葡萄糖溶液（0-20 %）进行性能评估，显示出优异的折射率传感，达到715.5 nm/RIU的高灵敏度和3.91× 10−5 RIU的高分辨率。此外，通过检测人IgG验证了生物传感能力，检测限（LOD）为14.35 nM，具有明显的共振波长偏移，证实了特异性的分子结合。这些结果突出了一个具有成本效益、小型化和高性能的SPR平台，在即时诊断、环境监测和食品安全应用方面具有巨大的潜力。

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引用次数: 0

Low-resistivity nanocomposite electrodes based on carbon nanotubes and a water- and organic-solvent-soluble PEDOT derivative for high-performance actuators 基于碳纳米管和水和有机溶剂可溶性PEDOT衍生物的高性能执行器低电阻率纳米复合电极

IF 4.9 3区工程技术 Q2 ENGINEERING, ELECTRICAL & ELECTRONIC

Sensors and Actuators A-physical

Pub Date : 2025-12-13 DOI: 10.1016/j.sna.2025.117385

Naohiro Terasawa , Mutsuo Tanaka

Poly(3,4-ethylenedioxythiophene):poly(4-styrenesulfonate) (PEDOT:PSS) is widely available as an aqueous dispersion of colloidal particles; however, it has several technical limitations, including poor solubility in water and organic solvents, which hinder processability and device performance. This study synthesized a novel PEDOT derivative bearing a methylsulfonic acid moiety, poly[(2,3-dihydrothieno[3,4-b][1,4]dioxin-2-yl)methylsulfonic acid] (PEDOT-SO₃H), which is highly soluble in aqueous and organic media. The performance of PEDOT-SO₃H was investigated by fabricating nanocomposite electrodes and actuators composed of highly conductive single-walled carbon nanotubes synthesized via the super-growth (SG) method (SG-SWCNTs), PEDOT-SO₃H, and one of two ionic liquids (ILs). Thus, the underlying mechanisms were observed and determined to be a combination of electric double-layer and faradaic capacitance. The electromechanical and electrochemical properties of the SG-SWCNT/PEDOT-SO₃H/IL composites were compared with those of previously developed SG-SWCNT/PEDOT:PSS/IL and SG-SWCNT/IL composites. The PEDOT-SO₃H-based electrode demonstrated significantly lower volume and surface resistivity and a higher specific capacitance than the PEDOT:PSS-based electrode. Furthermore, the PEDOT-SO₃H-based actuators showed greater maximum strain than PEDOT:PSS-based actuators. These results indicate that PEDOT-SO₃H can improve the performance of actuators. The frequency-dependent strain behavior was accurately predicted using a kinetic model based on double-layer charging, which confirmed that the actuator operated via a combination of double-layer and faradaic capacitance mechanisms. In conclusion, PEDOT-SO₃H offers superior conductivity, capacitance, and strain performance compared with PEDOT:PSS, making it a promising material for next-generation soft actuators, particularly in biomedical and flexible electronic applications.

聚（3,4-乙烯二氧噻吩）：聚（4-苯乙烯磺酸盐）（PEDOT:PSS）作为胶体颗粒的水分散体广泛应用；然而，它有几个技术限制，包括在水和有机溶剂中的溶解度差，这阻碍了可加工性和设备性能。本研究合成了一种具有甲基磺酸基团的新型PEDOT衍生物，聚[（2,3-二氢噻吩[3,4-b][1,4]二恶英-2-酰基）甲基磺酸](PEDOT- so3h)，该衍生物在水和有机介质中高度可溶。通过制备由超生长（SG）法合成的高导电性单壁碳纳米管（SG- swcnts）、PEDOT-SO3H和两种离子液体中的一种（il）组成的纳米复合电极和致动器，研究了PEDOT-SO3H的性能。因此，观察并确定了潜在的机制是双电层和法拉第电容的结合。将SG-SWCNT/PEDOT- so3h /IL复合材料的机电和电化学性能与先前开发的SG-SWCNT/PEDOT:PSS/IL和SG-SWCNT/IL复合材料进行了比较。PEDOT- so3h基电极比PEDOT: pss基电极具有更低的体积和表面电阻率和更高的比电容。此外，基于PEDOT- so3h的致动器比基于PEDOT: pss的致动器显示出更大的最大应变。这些结果表明，PEDOT-SO3H可以改善执行器的性能。利用基于双层充电的动力学模型准确预测了频率相关的应变行为，证实了执行器是通过双层和法拉第电容机制的组合工作的。总之，与PEDOT:PSS相比，PEDOT- so3h具有优越的电导率、电容和应变性能，使其成为下一代软执行器的有前途的材料，特别是在生物医学和柔性电子应用中。

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引用次数: 0

A comprehensive review of EEG electrode technologies: Advancements, applications, and future directions 脑电电极技术的综合综述：进展、应用和未来方向

IF 4.9 3区工程技术 Q2 ENGINEERING, ELECTRICAL & ELECTRONIC

Sensors and Actuators A-physical

Pub Date : 2025-12-13 DOI: 10.1016/j.sna.2025.117396

Mahnaz Bayat , Javad Safaie , Sahar Mollazadeh Beidokhti , Fabrice Wallois

Electroencephalography remains a fundamental tool in neurological diagnostics, cognitive research, and emerging consumer applications. This comprehensive review critically examines the technological landscape of non-invasive EEG electrodes through a novel comparative framework rather than a conventional chronological analysis. We systematically evaluate wet, semi-dry, and dry electrode technologies across four key dimensions: material and design innovations, signal quality metrics, clinical and research applications, and implementation challenges. Our analysis reveals that while standard wet electrodes remain the gold standard for signal fidelity, they nevertheless require extensive setup, cause notable discomfort—particularly for children and long-term users, and demand ongoing gel reapplication, all of which limit their practicality in many real-world settings. Significant advancements in semi-dry electrodes now address these shortcomings by offering comparable performance with reduced preparation time and enhanced usability. Dry electrodes, despite inherently higher impedance, demonstrate increasing viability for long-term and ambulatory monitoring when paired with appropriate signal processing techniques. This review provides a decision framework for selecting optimal electrode technologies based on specific application requirements, subject characteristics, and recording environments. We identify critical research gaps, particularly in standardization methods, cross-population validation, and integration with emerging materials. As EEG applications expand beyond traditional clinical settings into consumer markets, this review offers valuable guidance for researchers, clinicians, and technology developers navigating the rapidly evolving landscape of EEG electrode technologies.

脑电图仍然是神经学诊断、认知研究和新兴消费者应用的基本工具。这篇全面的综述通过一个新颖的比较框架，而不是传统的时间顺序分析，批判性地考察了非侵入性脑电图电极的技术前景。我们系统地评估湿、半干和干电极技术在四个关键方面：材料和设计创新、信号质量指标、临床和研究应用以及实施挑战。我们的分析表明，虽然标准湿电极仍然是信号保真度的金标准，但它们仍然需要大量的设置，引起明显的不适，特别是对于儿童和长期用户，并且需要不断地重新涂抹凝胶，所有这些都限制了它们在许多现实环境中的实用性。现在，半干电极的重大进步通过缩短制备时间和增强可用性来提供类似的性能，从而解决了这些缺点。尽管干电极本身具有更高的阻抗，但当与适当的信号处理技术配对时，它在长期和动态监测方面的可行性越来越高。这篇综述提供了一个决策框架，以选择最佳电极技术的基础上，具体的应用需求，主题特点和记录环境。我们确定了关键的研究差距，特别是在标准化方法、跨群体验证和与新兴材料的整合方面。随着脑电图应用从传统的临床环境扩展到消费者市场，这篇综述为研究人员、临床医生和技术开发人员在脑电图电极技术快速发展的前景中导航提供了有价值的指导。

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引用次数: 0

Wireless IoT-based continuous ECG monitoring using ESP32 and thingspeak based performance analysis across age groups 基于无线物联网的连续心电图监测，使用ESP32和基于thingspeak的跨年龄组性能分析

IF 4.9 3区工程技术 Q2 ENGINEERING, ELECTRICAL & ELECTRONIC

Sensors and Actuators A-physical

Pub Date : 2025-12-13 DOI: 10.1016/j.sna.2025.117392

Kokkonda Mounika, Shaik Vaseem Akram

Continuous cardiac activity monitoring for the early identification of cardiovascular diseases, but current ECG systems are cumbersome with limited mobility, expensive, or without real-time connectivity. This work presents the development and design of a wireless, IoT-based real-time ECG monitoring system using the ESP32 micro controller and AD8232 ECG sensor, coupled with the cloud through Thing Speak. The system continuously tracks heart rate fluctuations among various age groups, wirelessly transmitting ECG data over Wi-Fi in real time for storage, visualization, and analysis. The research tests the ESP32's wireless communication capabilities with an emphasis on latency, power consumption, and network efficiency in a real-time healthcare monitoring environment. Heart rate information was gathered from participants in different age groups children (3−5, 6−11), young adults (19−35), middle-aged individuals (36−55, 55−75), and elderly persons (75 and above)—at four time intervals: morning (5:00–7:00 AM), afternoon (1:00–3:00 PM), evening (5:00–7:00 PM), and night (8:00–10:00 PM). This facilitated circadian variability in heart rate patterns to be examined. The suggested system not only facilitates continuous real-time ECG observation but also proves to perform early detection of cardiac irregularities with preliminary evidence through waveform deviation and heart rate variability pattern analysis across various age groups. Results from the experiment showed that young subjects had more heart rate variability, whereas older adults showed consistent readings, highlighting the necessity of age-targeted and time-dependent cardiac surveillance. The system attained a mean transmission latency of 0.35 s, proving its viability for constant real-time health monitoring. Nevertheless, issues of power efficiency and network congestion suggest that power-efficient data transmission mechanisms are needed. This research highlights the capability of wireless IoT-based ECG monitoring for remote patient monitoring and early identification of cardiac abnormalities. Besides remote monitoring, the system facilitated detection of age-related and circadian changes in ECG and HRV patterns that hold useful clues for early identification of likely cardiac abnormalities.

持续的心脏活动监测用于心血管疾病的早期识别，但目前的ECG系统笨重，移动性有限，价格昂贵，或者没有实时连接。本文介绍了一种基于物联网的无线实时心电监测系统的开发和设计，该系统采用ESP32微控制器和AD8232心电传感器，并通过Thing Speak与云相结合。该系统持续跟踪不同年龄组的心率波动，通过Wi-Fi实时无线传输心电数据，用于存储、可视化和分析。该研究测试了ESP32的无线通信功能，重点是实时医疗监控环境中的延迟、功耗和网络效率。从不同年龄组的参与者(儿童（3 - 5岁，6 - 11岁），年轻人（19 - 35岁），中年人（36 - 55岁，55 - 75岁）和老年人（75岁及以上）中收集心率信息-在四个时间间隔：早上（5:00-7:00 AM），下午（1:00-3:00 PM），晚上（5:00-7:00 PM）和晚上（8:00-10:00 PM）。这有助于检查心率模式的昼夜变化。该系统不仅可以实现连续的实时心电图观察，而且可以通过对不同年龄组的波形偏差和心率变异性模式分析，证明可以早期发现心脏异常，并提供初步证据。实验结果显示，年轻受试者的心率变异性更大，而老年人的读数一致，这突出了针对年龄和时间依赖的心脏监测的必要性。该系统的平均传输延迟为0.35 s，证明了其持续实时健康监测的可行性。然而，电力效率和网络拥塞的问题表明，需要节能的数据传输机制。本研究强调了基于无线物联网的心电监测在患者远程监测和早期识别心脏异常方面的能力。除了远程监测外，该系统还有助于检测ECG和HRV模式的年龄相关和昼夜变化，为早期识别可能的心脏异常提供有用的线索。

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引用次数: 0

The optimization of magnet and coil configurations in a planar electromagnetic energy harvester for low-frequency, low-acceleration vibrations 用于低频、低加速度振动的平面电磁能量采集器磁体和线圈结构的优化

IF 4.9 3区工程技术 Q2 ENGINEERING, ELECTRICAL & ELECTRONIC

Sensors and Actuators A-physical

Pub Date : 2025-12-12 DOI: 10.1016/j.sna.2025.117390

Nouman Ghafoor, Jeff Punch, Valeria Nico

Electromagnetic vibration energy harvesters (EM-VEHs) are a potential sustainable alternative to batteries to power Wireless Sensor Nodes (WSNs) for Internet of Things (IoT) applications. This paper presents an innovative planar EM-VEH suitable for the low-frequency (< 15 Hz) and low-acceleration (0.05 g to 0.2 g, where g = 9.81 m/s²) in-plane vibrations prevalent in many IoT applications. The structure consists of three fixed-free beams, each attached at one end to the harvester’s housing and at the other to a shared single mass that acts as a holder for an array of magnets. A set of coils is located on a fixed frame in close proximity above the magnets. In-plane excitations induce oscillations of the beams in the in-plane direction and, hence, relative movement of magnets and coils. In this paper, using a combination of simulation and experimentation, eight different magnet configurations, three different magnet sizes, five different coil configurations and three different wire diameters are analyzed in order to determine an optimum magnet and coil combinations for the planar EM-VEH. The optimum design features an 8 × 3 Halbach magnetic array in combination with three round coils, each 3 mm thick, formed from wire of 0.1 mm diameter. With the coils connected in series / anti-series to an optimum load resistance of 1500 Ω, the harvester produces a power level of 3.35 mW at a resonance frequency of 15.2 Hz under acceleration levels of 0.2 g, yielding a projected Normalized Power Density (NPD) of 1950 μW/cm³·g².

电磁振动能量采集器（EM-VEHs）是一种潜在的可持续电池替代品，可为物联网（IoT）应用的无线传感器节点（wsn）供电。本文提出了一种创新的平面EM-VEH，适用于许多物联网应用中普遍存在的低频（< 15 Hz）和低加速度（0.05 g至0.2 g，其中g = 9.81 m/s2）面内振动。该结构由三根自由固定的梁组成，每根梁的一端连接到收割机的外壳上，另一端连接到一个共享的单一物体上，该物体作为一组磁铁的支架。一组线圈位于靠近磁铁上方的固定框架上。平面内激励引起梁在平面内方向上的振荡，从而引起磁体和线圈的相对运动。本文采用仿真与实验相结合的方法，对八种不同的磁体结构、三种不同的磁体尺寸、五种不同的线圈结构和三种不同的导线直径进行了分析，以确定平面电磁电磁驱动电机的最佳磁体和线圈组合。最佳设计的特点是一个8 × 3哈尔巴赫磁阵列，结合三个圆形线圈，每个3 毫米厚，由0.1 毫米直径的导线形成。线圈串联/反串联，最佳负载电阻为1500 Ω，在0.2 g的加速度水平下，在15.2 Hz的共振频率下，收割机产生3.35 mW的功率水平，预计归一化功率密度（NPD）为1950 μW/cm3·g2。

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引用次数: 0

A compact multifunctional sensing system utilizing a III-Nitride optoelectronic chip with an elastic optical fiber structure 一种采用弹性光纤结构的iii -氮化物光电子芯片的紧凑多功能传感系统

IF 4.9 3区工程技术 Q2 ENGINEERING, ELECTRICAL & ELECTRONIC

Sensors and Actuators A-physical

Pub Date : 2025-12-12 DOI: 10.1016/j.sna.2025.117395

Fan Shi , Jiawei Shi , Chengxiang Jiang , Jiaqi Yin , Jiabin Yan , Hongbo Zhu , Wei Cai , Yongjin Wang

A compact, portable, and multi-functional sensing system capable of measuring angle, tension and pressure is highly desirable for wearable applications. However, the complexity of component connections and the assembly of bulky light sources and detectors often result in a complicated configuration and a larger system footprint. Here, we introduce a compact multifunctional sensing system featuring a chip-scale GaN optoelectronic chip combined with an elastic optical fiber structure (EOFS). The GaN-on-sapphire chip monolithically integrates the light emitter and detector, offering a rapid response and a millimeter-scale footprint. The EOFS is formed by embedding a pair of plastic optical fibers (POF) within a silicon tube, leaving a hollow core segment in the central region. When mechanical force is applied to the EOFS, the on-chip detector senses the change in light transmission due to EOFS deformation, generating photocurrent to indicate the specific level of deformation. With this design, versatile measurements of angle, tension, and impact force are demonstrated. The proposed chip-integrated sensing system has advantages in low cost, miniaturization, and versatile detection, making it highly promising for applications in human motion detection, robotics and human-machine interfaces.

一个紧凑，便携，多功能传感系统，能够测量角度，张力和压力是非常理想的可穿戴应用。然而，元件连接的复杂性以及庞大的光源和检测器的组装通常会导致复杂的配置和更大的系统占地面积。在这里，我们介绍了一种紧凑的多功能传感系统，该系统采用芯片级GaN光电子芯片结合弹性光纤结构（EOFS）。蓝宝石晶片上的gan单片集成了光发射器和探测器，提供快速响应和毫米级的足迹。EOFS是通过在硅管内嵌入一对塑料光纤（POF）形成的，在中心区域留下一个空心核心段。当机械力作用于EOFS时，片上检测器感知到由于EOFS变形引起的光透射变化，产生光电流来指示特定的变形程度。通过这种设计，可以演示角度、张力和冲击力的多种测量方法。所提出的芯片集成传感系统具有低成本、小型化和多用途检测等优点，在人体运动检测、机器人和人机界面等领域具有广阔的应用前景。

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引用次数: 0

CSRR-based resonator for complex dielectric permittivity measurements up to 35 GHz 基于csrr的谐振器，用于高达35 GHz的复杂介电常数测量

IF 4.9 3区工程技术 Q2 ENGINEERING, ELECTRICAL & ELECTRONIC

Sensors and Actuators A-physical

Pub Date : 2025-12-12 DOI: 10.1016/j.sna.2025.117394

Georges Chehade, Sylvie Jarrix, Brice Sorli, Arnaud Vena

This paper presents the use of a circular complementary split ring resonator (CSRR) for characterizing the complex dielectric permittivity of various dielectric materials, such as polymers and biopolymers. The CSRR is etched into a ground plane and excited by a microstrip line. The CSRR is fabricated with a fast laser ablation technique, the latter providing a faster and more accessible alternative to conventional chemical etching processes. The transmission coefficient presents a shift in the resonant frequency when the resonator is loaded with a material under test (MUT). The influence on the resonant frequency of various geometrical parameters of the CSRR including substrate thickness is analyzed, providing insights for optimizing the design of a CSRR-based sensor. Then, a grounded coplanar waveguide microstrip (GCPW-MS) structure for excitation is proposed to enhance performance at high frequencies. A numerical model for the behavior of the CSRR is developed using a commercial 3D electromagnetic simulation software. The model allows to establish a relation between the resonant frequency and the permittivity of the MUT. Experimentally, a novelty presented here is that the proposed CSRR design was tested across a broad frequency range between 10 GHz and 35 GHz exceeding the frequency bands reported in the literature. The unknown permittivity of polymer materials, such as polydimethylsiloxane (PDMS) filled with carbon particles (17 and 25 %), and a biopolymer material, wheat gluten, is determined using the CSRR. Results show a good correlation between simulated and measured values of the loss factor and dielectric constant of these materials, validating the use of this CSRR for dielectric characterization in the high frequency bands. Another originality of this paper is the measurement results of CSRR showing clear resonance frequency shifts for 25 µm thick commercial PEEK and Kapton materials, highlighting the potential of this CSRR for thin-film sensor applications.

本文介绍了利用圆形互补分裂环谐振器（CSRR）来表征各种介电材料（如聚合物和生物聚合物）的复介电常数。CSRR被蚀刻在接地面上，并由微带线激励。CSRR是用快速激光烧蚀技术制造的，后者提供了一种比传统化学蚀刻工艺更快、更容易获得的替代方法。当加载被测材料（MUT）时，谐振腔的透射系数呈现出谐振频率的偏移。分析了包括衬底厚度在内的各种几何参数对谐振频率的影响，为优化设计基于CSRR的传感器提供了参考。然后，提出了一种接地的共面波导微带（GCPW-MS）激励结构，以提高高频激励性能。利用商业三维电磁仿真软件建立了CSRR的数值模型。该模型可以建立MUT谐振频率与介电常数之间的关系。在实验中，本文提出的一个新颖之处在于，所提出的CSRR设计在10 GHz和35 GHz之间的宽频率范围内进行了测试，超出了文献中报道的频带。聚合物材料的未知介电常数，如填充碳颗粒的聚二甲基硅氧烷（PDMS）（17%和25% %），以及生物聚合物材料麦麸，使用CSRR来确定。结果表明，这些材料的损耗因子和介电常数的模拟值与实测值之间具有良好的相关性，验证了该CSRR用于高频段介电特性的使用。本文的另一个独创性是CSRR的测量结果，显示25 µm厚的商用PEEK和Kapton材料的明显共振频移，突出了该CSRR在薄膜传感器应用中的潜力。

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引用次数: 0

Design-dependent Q-factor spectroscopy: Impact of surface oxidation on dissipation in 2 micrometer thick MEMS resonators 设计相关的q因子光谱：表面氧化对2微米厚MEMS谐振器耗散的影响

IF 4.9 3区工程技术 Q2 ENGINEERING, ELECTRICAL & ELECTRONIC

Sensors and Actuators A-physical

Pub Date : 2025-12-11 DOI: 10.1016/j.sna.2025.117389

Dominik Huber, Andre Gesing, Georg Pfusterschmied, Daniel Platz, Ulrich Schmid

Several intrinsic and extrinsic contributing loss mechanisms make the estimation of the total Q-factor

Q

of MEMS resonators challenging, as it is influenced by many parameters. Experimentally, however, only the total Q-factor of a vibrational mode can be measured; so for the study of environmental conditions, pressure and temperature sweeps are typically performed to provide knowledge about fluidic and thermo-elastic dissipation. However, the contributing amounts of intrinsic damping mechanisms cannot be split into their individual components. In this study, we explore the dynamics of many non-slender MEMS resonators while varying the width. We call this technique design-dependent Q-factor spectroscopy (DDQS). The use of hundreds of devices with several out-of-plane resonance modes within DDQS allows the separation of the total Q-factor into the different dissipation mechanisms in thin films and MEMS resonators. Experimental results discussed alongside theoretical predictions indicate how the variation of a geometrical parameter of the resonator allows access to frequency regions with different dominant dissipation mechanisms. Furthermore, we evaluate the impact of surface-related losses and fluidic damping, showing a two-fold improvement in

Q

by removing the native grown silicon dioxide layer under high vacuum conditions. Our results highlight the advantages of optimizing the design of MEMS resonators within DDQS to understand the contributions to energy dissipation and lead to a new MEMS design approach.

由于MEMS谐振器的总Q因子Q受到许多参数的影响，一些内在和外在的损耗机制使得估计总Q因子Q具有挑战性。然而，在实验中，只能测量振动模态的总q因子；因此，对于环境条件的研究，通常进行压力和温度扫描，以提供有关流体和热弹性耗散的知识。然而，内在阻尼机制的贡献量不能分割成它们各自的组成部分。在这项研究中，我们探讨了许多非细长MEMS谐振器在改变宽度时的动力学。我们称这种技术为设计相关q因子光谱（DDQS）。在DDQS中使用数百个具有几种面外共振模式的器件，可以将总q因子分离到薄膜和MEMS谐振器中的不同耗散机制中。与理论预测一起讨论的实验结果表明，谐振器几何参数的变化如何允许进入具有不同主要耗散机制的频率区域。此外，我们评估了表面相关损失和流体阻尼的影响，表明在高真空条件下去除天然生长的二氧化硅层可以使Q提高两倍。我们的研究结果强调了在DDQS中优化MEMS谐振器设计的优势，以了解能量耗散的贡献，并导致新的MEMS设计方法。

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引用次数: 0