Sensors and Actuators A-physical最新文献

{"title":"Air-coupled ultrasound transduction improvement using vertical piezoelements’ array","authors":"Linas Svilainis ,&nbsp;Valdas Eidukynas ,&nbsp;Luca De Marchi ,&nbsp;Andrius Chaziachmetovas","doi":"10.1016/j.sna.2025.117178","DOIUrl":"10.1016/j.sna.2025.117178","url":null,"abstract":"<div><div>Novel transducer construction is proposed: array of PVDF film strips placed parallel to each other with air gaps between. Films are oriented in such way that strip extension (31 mode) is aligned with emission direction. Transduction is improved by providing better acoustic impedance match to air and increased displacement of emitting surface. Two distinct operation modes are presented: i) emission from the gaps ii) emission from membrane attached to the edges at array top with lower edges backed.</div><div>In gap emission mode, the transduction efficiency is increased because of two mechanisms. The pressure produced by the expansion of the individual films is concentrated into narrow gap. Also, emission of edges due to height extension. Height extension (31 mode) is much higher than thickness expansion (33 mode) if film height is larger than film thickness. Low, 500 Rayl, equivalent acoustic impedance of gap emission is achieved at film thickness 10 μm and gap with 50 μm.</div><div>In membrane emission mode, only extension (31 mode) is used, pressure emitted is increased due to large membrane displacement and better match to air. Equivalent acoustic impedance is 500 kRayl at PVDF film thickness 40 μm and 200 μm air gap. Displacement is maximized if PVDF film with large transverse piezoelectric coefficient d₃₁ is used.</div><div>Experimental measurements are presented. Transmission sensitivity peak for gap emission was 155 mPa/V, for membrane emission mode it was 320 mPa/V. Impressive, more than 270 % fractional bandwidth was confirmed experimentally.</div></div>","PeriodicalId":21689,"journal":{"name":"Sensors and Actuators A-physical","volume":"396 ","pages":"Article 117178"},"PeriodicalIF":4.9,"publicationDate":"2025-10-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145326740","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Wrinkled and cracked sensory structure towards multidirectional strain detection","authors":"Zhiyuan Zhang ,&nbsp;Jiaqi He ,&nbsp;Longwei Ke ,&nbsp;Huijuan Lin ,&nbsp;Yan Yan ,&nbsp;Kun Rui ,&nbsp;Jixin Zhu","doi":"10.1016/j.sna.2025.117185","DOIUrl":"10.1016/j.sna.2025.117185","url":null,"abstract":"<div><div>Flexible sensors have emerged as a research hotspot in areas of human healthcare monitoring, smart home, and human-computer interaction. However, directional strain tracking is also critical in practical situations besides of the improved sensitivity and strain range of the sensor. Herein, metallic N-VO_0.9 nanosheets are combined with silver nanowires (Ag NWs) to form interconnecting conductive network. Furthermore, the N-VO_0.9/Ag NWs with wrinkle and crack structures formed through the pre-stretching strategy, can cause different electrical changes when exposure to strains. Thus, in addition to sensing performance of prominent sensitivity, quick response time, and outstanding cyclic stability, the designed strain sensor harnesses good multi-directional selectivity, effectively tracks intricate body motions and monitors badminton serves, showcasing its value for sports training.</div></div>","PeriodicalId":21689,"journal":{"name":"Sensors and Actuators A-physical","volume":"396 ","pages":"Article 117185"},"PeriodicalIF":4.9,"publicationDate":"2025-10-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145364683","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Hysteresis compensation approach via combination of origami pump and soft pneumatic actuator","authors":"Seongkwan Jang,&nbsp;Youngsu Cha","doi":"10.1016/j.sna.2025.117188","DOIUrl":"10.1016/j.sna.2025.117188","url":null,"abstract":"<div><div>This paper proposes a new hysteresis compensation approach by combining an origami pump and a soft pneumatic actuator with counteractive hysteretic behaviors. Theoretically, the composition of two counteractive hysteresis loops results in hysteresis compensation. Hysteresis compensation respect to the variation of counteractive hysteresis is shown through the modified Prandtl-Ishlinskii (P-I) model. For the application of this theoretical framework, we utilize the origami pump and soft pneumatic actuator. Specifically, the origami pump has clockwise hysteresis, and the soft pneumatic actuator has counterclockwise hysteresis. Herein, we analyze the hysteresis compensation with series of experiments. In the experiments, we test various conditions of the origami pump and soft pneumatic actuator. Regardless of varying frequencies and amplitudes, the composition can result in effective hysteresis compensation, with decreased hysteresis loop areas.</div></div>","PeriodicalId":21689,"journal":{"name":"Sensors and Actuators A-physical","volume":"396 ","pages":"Article 117188"},"PeriodicalIF":4.9,"publicationDate":"2025-10-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145364603","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Emerging material strategies for enhanced dielectric elastomer actuation","authors":"Hemant Hegde ,&nbsp;Seok-Han Lee ,&nbsp;Sang-Youn Kim","doi":"10.1016/j.sna.2025.117177","DOIUrl":"10.1016/j.sna.2025.117177","url":null,"abstract":"<div><div>Dielectric elastomers (DEs) are currently the most promising classes of electroactive polymers for actuation application due to their high deformability, quick response, lightweight, and mechanical compliance. Over the last two decades, extensive research efforts have been made to address the inherent limitations of conventional DE materials, such as high actuation voltage, low dielectric permittivity, and electromechanical instability during prolonged use. This review provides a comprehensive overview of recent development and optimization of DE material for actuation applications. The most critical subjects of discussion are the optimization of key parameters in dielectric elastomer actuator (DEA) material design that decides its performance and the mitigation of common failure modes observed in existing dielectric elastomers. In this regards, key strategies such as molecular design and chemical modification of elastomer backbones, addition of suitable fillers, creation of soft nanocomposites, block copolymer design and interpenetrating polymer network designs are reviewed. Also, dielectric, mechanical, and interfacial properties and their synergistic effects on actuation performance are addressed elaborately. In addition, novel electrode material research towards actuation strain improvement is reviewed. Finally, current issues and future research directions are outlined for the development of the next generation of high-performance, low-voltage dielectric elastomer actuators.</div></div>","PeriodicalId":21689,"journal":{"name":"Sensors and Actuators A-physical","volume":"396 ","pages":"Article 117177"},"PeriodicalIF":4.9,"publicationDate":"2025-10-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145325905","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The pump laser frequency stabilization method based on magnetic field signal in NMR magnetometer","authors":"Lan Xiao ,&nbsp;Jianli Li ,&nbsp;Hao Tian ,&nbsp;Xuelei Wang ,&nbsp;Yibo Shao ,&nbsp;Zhanchao Liu","doi":"10.1016/j.sna.2025.117186","DOIUrl":"10.1016/j.sna.2025.117186","url":null,"abstract":"<div><div>The nuclear magnetic resonance (NMR) magnetometer, leveraging spin-exchange optical pumping, has the advantage of small volumes and high accuracy. The pump laser frequency is a critical factor in the optical pumping process as it affects the magnetic field measurement. Traditional frequency stabilization methods rely on monitoring the transmitted laser power through the vapor cell to lock the laser to the absorption spectrum. However, for achieving the signal enhancement of NMR magnetometers, a reflective pump structure is applied; the transmitted beam is redirected by a retro-reflective mirror to repump alkali atoms, eliminating the conventional transmitted light path and thereby precluding transmitted laser power-based stabilization. Therefore, a pump laser frequency stabilization approach is proposed based on the magnetic field signal. Theoretical analysis establishes a deterministic correlation between the magnetic field amplitude and pump laser frequency detuning, identifying the frequency stabilization method utilizing the zero point of the magnetic field signal’s first-order derivative. Experimental validation demonstrates frequency stability with a maximum variance of 18.8 MHz (1σ: ±3.0 MHz) over 2-hour continuous operation, matching the performance of absorption-based methods (16.5 MHz, 1σ: ±4.5 MHz). Although short-term frequency noise increases, the baseline magnetic field sensitivity is maintained. This approach not only simplifies the system architecture but also ensures compatibility with reflective pump structures, advancing the NMR magnetometer with the reflective structure of pump light.</div></div>","PeriodicalId":21689,"journal":{"name":"Sensors and Actuators A-physical","volume":"396 ","pages":"Article 117186"},"PeriodicalIF":4.9,"publicationDate":"2025-10-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145364605","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Laser-tapered optical fibers with LSPR activation for enhanced refractive index sensing","authors":"Nurul Hidayat ,&nbsp;Arif Hidayat ,&nbsp;Latifatul Aisyah Nabila ,&nbsp;Siti Azimatul Luthfiyyah ,&nbsp;Ahmad Taufiq ,&nbsp;Muhammad Safwan Abd Aziz ,&nbsp;Hazri Bakhtiar","doi":"10.1016/j.sna.2025.117181","DOIUrl":"10.1016/j.sna.2025.117181","url":null,"abstract":"<div><div>The integration of localized surface plasmon resonance (LSPR) effects with tapered optical fibers has significantly improved refractive index (RI) sensing performance. This study introduces an optimized RI sensor using gold nanospheres (AuNSs) coated on tapered coreless termination fibers (TCTFs), which demonstrate a remarkable improvement in sensitivity. The TCTFs were optimized in terms of their taper waist diameter through the variation of CO₂ laser power. Subsequently, 11.26 nm average-sized AuNSs synthesized by citrate reduction method were strongly attached to the optimized TCTF surface via thiol-functionalization. The LSPR peak of AuNSs, recorded by ultraviolet visible spectroscopy (UV-Vis), was ∼522 nm. The face-centered cubic crystal structure and nanospherical shapes of AuNSs were respectively obtained from X-ray diffraction (XRD) and high-resolution transmission electron microscopy (HR-TEM) data. Furthermore, from the field emission scanning electron microscopy (FE-SEM) image, the average thickness of the attached AuNSs on the TCTF was 88 nm. The sensitivity of the unmodified CTF sensor was 50.97 ± 4.68 nm/RIU and the AuNSs-coated TCTF was 254.42 ± 20.75 nm/RIU. In other words, it exhibited a ∼400 % improvement in RI sensitivity. Five repetitive measurements indicated that fluctuation of sensitivity was ±3.93 nm/RIU, indicating good repeatability. The stability test for 20 min showed that the sensor experienced small wavelength shift variations of ±0.362 nm for refractive indices of 1.33 and 1.39, and ±0.726 nm for refractive index of 1.43. These results established AuNSs-coated TCTFs as a promising platform for high-performance RI sensing applications.</div></div>","PeriodicalId":21689,"journal":{"name":"Sensors and Actuators A-physical","volume":"396 ","pages":"Article 117181"},"PeriodicalIF":4.9,"publicationDate":"2025-10-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145326737","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Thermochromic 2D (n-BA)2NiIxCl4-x perovskite interlayer-integrated self-powered and reverse-biased Si-photodiode","authors":"Ali Baltakesmez ,&nbsp;Sebahaddin Alptekin","doi":"10.1016/j.sna.2025.117175","DOIUrl":"10.1016/j.sna.2025.117175","url":null,"abstract":"<div><div>The thermochromic 2D perovskite materials have gained interest due to their potential applications in smart windows, sensors, optical switches, and temperature indicators. In this study, we have focused on the thermochromic interlayer effect on the electrical performance of the (photo)diode. A novel 2D (n-BA)₂NiI_xCl₄_-x perovskite thin film was characterized in terms of its morphological, structural, and optical properties. Additionally, an Au/(n-BA)₂NiI_xCl₄_-x/n-Si/Al device was fabricated to determine the effect of the thermochromic perovskite interlayer. The surface-SEM images showed the presence of microcrystal perovskite plates. The diffraction pattern exhibited an intense peak at 2θ = 9.81°, which corresponds to an interplanar d-spacing of 9.1 Å, supporting the presence of the 2D structure. Furthermore, the theoretical stoichiometric ratio has deviated due to the reversible 0D and 2D perovskite formation by the thermochromic effect. The band gap of the film on the glass substrate changed from 3.14 eV to 2.43 eV. The Au/(n-BA)₂NiI_xCl₄_-x/n-Si/Al device showed a thermally switching feature with increasing threshold voltage in the forward bias, and the leakage current significantly increased in the reverse bias. Additionally, the device has photodetection features which can be switched between the photodiode and photoconductor, and thus it presents the responsivity of both modes in one device (self-powered (0 V), reversed-biased (-0.9 V)). The significant rectifying and photoresponse performances have been achieved by Au/(n-BA)₂NiI_xCl₄_-x/n-Si/Al device, such as R_max: 1.17 A/W, D_max: 4.6 × 10¹⁰ Jones, NEP_min: 2.99 × 10⁻¹² W/Hz^1/2, and EQE_max: 262 % in the photodiode mode, and R_max: 46 mA/W, D_max: 1.7 × 10¹⁰ Jones, NEP_min: 7.07 × 10⁻¹² W/Hz^1/2, and EQE_max: 10.5 % in the photoconductor mode. Therefore, as a novel concept, the thermochromic perovskite-integrated diode has shown potential for new applications in the (opto)electronic field. Therefore, the findings may provide a source of ideas for new research.</div></div>","PeriodicalId":21689,"journal":{"name":"Sensors and Actuators A-physical","volume":"396 ","pages":"Article 117175"},"PeriodicalIF":4.9,"publicationDate":"2025-10-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145326734","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"On-chip peristaltic pump for pulse-free and accurate liquid delivery in microfluidics","authors":"Xinjie Zhang ,&nbsp;Yang Bao ,&nbsp;Yuyang Liu ,&nbsp;Yujie Pei ,&nbsp;Ayobami Elisha Oseyemi ,&nbsp;Fangrui Lv ,&nbsp;Akihide Hibara","doi":"10.1016/j.sna.2025.117182","DOIUrl":"10.1016/j.sna.2025.117182","url":null,"abstract":"<div><div>Peristaltic pumps are widely used for continuous liquid delivery across various applications. However, their inherent pulsatile flow leads to significant fluctuations, especially in microfluidic systems. In this work, we present an on-chip peristaltic pump for continuous, pulse-free, and precise liquid delivery in microfluidics. The pump utilizes a stepper motor driving three rolling bearings to propel liquid to a microfluidic carrier chip. To mitigate flow pulsation, two air chambers are integrated into the chip as flow stabilizers. The pump achieves stable and accurate flowrates ranging from a few microliters to several hundred microliters per minute, with motor speeds of 10–250 rpm. The average flow rates and total flow volume exhibit a strong linear relationship with motor speed, with a coefficient of determination (R²) close to 1. Notably, the instantaneous flow variation is reduced within 3 % with air chambers, while the pump without the air chambers produces significantly high flow variation (∼ 25.5 %). To demonstrate its applicability, the on-chip pump is employed for sample and sheath flow control in an inertial microfluidic chip, enabling efficient separation of 15 μm and 6 μm particles. These results highlight the pump’s stability, precision, and suitability for feasible applications in microfluidics.</div></div>","PeriodicalId":21689,"journal":{"name":"Sensors and Actuators A-physical","volume":"396 ","pages":"Article 117182"},"PeriodicalIF":4.9,"publicationDate":"2025-10-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145326739","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Heat-responsive poly(styrene-block-ethylene-butylene-block-styrene)/poly(butyl methacrylate-co-isobutyl methacrylate) blends and their applications in 4D printing","authors":"Emre Tekay ,&nbsp;Betül Aybakan ,&nbsp;Vahap Uygar Aslan","doi":"10.1016/j.sna.2025.117176","DOIUrl":"10.1016/j.sna.2025.117176","url":null,"abstract":"<div><div>Recent advancements in additive manufacturing technology have also introduced new research areas in materials science. The processing of shape memory polymers (SMPs) using 3D printers has led to the emergence of 4D printing technology. The present study focused on the creation of new polymer blends that incorporate maleic anhydride grafted SEBS (SEBS-g-MA) alongside poly(butyl methacrylate-co-isobutyl methacrylate) (poly(BM-co-iBM)) in diverse compositions, aimed at facilitating advancements in 4D printing technologies. In the formulation with a weight ratio of SEBS-g-MA to poly(BM-co-iBM) of 6/4 (60S-40B), a co-continuous morphology was detected. With a rising concentration of SEBS-g-MA in the polymer blends, the T_g of the poly(BM-co-iBM) phase exhibited an upward shift. Dynamic mechanical analysis results indicate that the poly(BM-co-iBM) polymer within the blends transitioned from a glassy state to a rubbery state before reaching 55°C, which resulted in a pronounced reduction in the storage modulus at this temperature. On the other hand, with an increase in the amount of poly(BM-co-iBM) in the blend, there was a corresponding increase in the elastic modulus values, while the elongation at break values diminished. The results from the thermo-responsive shape memory analysis demonstrated that the 60S-40B blend provided the most favorable performance. A filament suitable for 4D printing was developed from this blend for application in fused deposition modeling printers. Employing the filament, objects produced via 4D printing were developed for applications such as lifting devices, stents, door closers, cogwheels, and robotic grippers, and their shape memory properties were evaluated.</div></div>","PeriodicalId":21689,"journal":{"name":"Sensors and Actuators A-physical","volume":"396 ","pages":"Article 117176"},"PeriodicalIF":4.9,"publicationDate":"2025-10-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145326345","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Development of highly sensitive UV-visible photodetector based on drop-cast Li-ZnO/p-Si heterojunction","authors":"Manish Singh ,&nbsp;Mohd. Shahid Khan ,&nbsp;Arun Kumar ,&nbsp;Stuti Tomar ,&nbsp;Tejendra K Gupta ,&nbsp;Sunil Kumar ,&nbsp;Vijay Kumar ,&nbsp;Ravi Kant Choubey","doi":"10.1016/j.sna.2025.117171","DOIUrl":"10.1016/j.sna.2025.117171","url":null,"abstract":"<div><div>In the present study, pristine and Li-doped ZnO nanoparticles were synthesized using a well-established, cost-effective chemical co-precipitation method. The synthesized nanoparticles were used to fabricate Ag/ZnO/p-Si/Ag heterojunction photodetectors through drop-casting technique, targeting UV and visible light detection applications. The Structural, optical, and morphological characterizations were performed using XRD, UV-Vis, FTIR, PL, XPS, FESEM, HRTEM, and ICP-MS. XRD confirmed the formation of the hexagonal wurtzite phase of ZnO while FTIR verified the presence of Zn–O functional groups. The PL spectra indicated defect-related emissions, whereas XPS/ICP-MS confirmed the presence of Zn²⁺ and O²⁻ species and successful incorporation of Li. The morphology of the synthesized nanoparticles was analyzed using FESEM and HRTEM. The fabricated photodetectors showed efficient UV (50 μW/cm²) and visible (30 mW/cm²) light response, with 2 % Li-doped ZnO exhibiting faster response/recovery, nearly double the quantum efficiency of pristine ZnO, and stable switching. The synthesized nanoparticles also displayed antibacterial activity against <em>E. coli</em>, highlighting potential applications in photodetection and biomedical fields.</div></div>","PeriodicalId":21689,"journal":{"name":"Sensors and Actuators A-physical","volume":"396 ","pages":"Article 117171"},"PeriodicalIF":4.9,"publicationDate":"2025-10-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145326741","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}